Ammonia mixed fuel, production apparatus for ammonia mixed fuel, production method for ammonia mixed fuel, supply apparatus for ammonia mixed fuel, combustion apparatus for ammonia mixed fuel, power generation equipment using ammonia mixed fuel, and transportation equipment using ammonia mixed fuel

Abstract

To provide an ammonia mixed fuel capable of efficiently burning ammonia.SOLUTION: An ammonia mixed fuel comprises: ammonia in a liquefaction state; and a combustion improver in the liquefaction state that assists combustion of the ammonia. The combustion improver is a component of at least one of (a) liquefied petroleum gas, naphtha, gasoline, kerosene, and light oil, (b) a feedstock hydrocarbon that is at least one hydrocarbon species contained as a component in any one of the liquefied petroleum gas, the naphtha, the gasoline, the kerosene, and the diesel oil, and (c) a raw material alcohol that is an alcohol having 3 or less carbon atoms. The ammonia mixed fuel is in a gas-liquid equilibrium state, and at least a part of a liquid phase portion of the ammonia mixed fuel is in a solution state in which the ammonia and the combustion improver are mutually dissolved, or is in an emulsion state of the ammonia and the combustion improver.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an ammonia mixed fuel, a production device for the ammonia mixed fuel, a production method for the ammonia mixed fuel, a supply device for the ammonia mixed fuel, a combustion device for the ammonia mixed fuel, a power generation facility using the ammonia mixed fuel, and a transportation device using the ammonia mixed fuel.

Background Art

[0002] Due to recent regulations on greenhouse gas (hereinafter referred to as GHG) emissions, there is a demand to convert from conventionally widely used fossil fuels (e.g., gasoline, kerosene, light oil, heavy oil, coal, etc.) that generate carbon dioxide upon combustion to other fuels that can suppress GHG emissions. In contrast, ammonia does not contain carbon, so carbon dioxide is not generated during combustion. Therefore, ammonia has been regarded as a promising alternative fuel in recent years to meet GHG regulations. However, ammonia has a very high ignition temperature and an extremely slow combustion rate compared to conventional fossil fuels, so it is difficult to stably combust it alone. For this reason, technologies are known in which light oil or other liquid hydrocarbon fuels, or gas fuels such as methane and hydrogen, are added to ammonia as a combustion aid to assist the combustion of ammonia.

[0003] For example, in a combustion device simulating a two-stroke diesel engine capable of periodically pressurizing and compressing the air-fuel mixture in the combustion chamber, pressurized liquefied ammonia and a small amount of light oil as a pilot fuel are directly injected into the combustion chamber into which air is introduced, and it has been reported that diffusion combustion required for the operation of a diesel engine becomes possible (Non-Patent Document 1). According to Non-Patent Document 1 above, in the direct injection combustion of liquefied ammonia, the liquefied ammonia is injected into the diesel engine and vaporized in the same manner as a conventional hydrocarbon-based volatile fuel, and is heated by the self-ignition combustion after the evaporation of the light oil of the pilot fuel, and then the ammonia also ignites and undergoes diffusion combustion.

[0004] In Non-Patent Document 2, it is reported that pre-vaporized ammonia corresponding to 70% of the whole on a calorific value basis is premixed in advance with hydrogen as a combustion improver corresponding to 30% on a calorific value basis, nitrogen with a volume ratio of hydrogen of 1 / 3, and a predetermined amount of air, and then injected into the combustion device of a four-stroke engine and spark-ignited, enabling combustion with an unburned rate of 2% and operation of the engine. Here, nitrogen is added to the fuel gas because it is assumed that at the time of practical application, hydrogen produced in situ by catalytic decomposition of a part of ammonia (reaction formula: NH3 → 3 / 2H2 + 1 / 2N2) is used as a combustion improver, and the nitrogen by-produced at that time is also added to the fuel gas together to simulate the situation.

[0005] In Non-Patent Document 3, for the purpose of increasing the combustion speed and stabilizing combustion, evaluations such as the laminar combustion speed of a premixed gas in which pre-vaporized ammonia is mixed with hydrogen or methane and a predetermined amount of air, and evaluations of turbulent combustion behavior assuming application to gas turbines, etc. are reported. In this document, it is confirmed that the laminar combustion speed of ammonia, which is as low as about 7 cm / s at 25°C under atmospheric pressure, increases by mixing with methane (laminar combustion speed of about 37 cm / s) or hydrogen (about 220 cm / s).

[0006] On the other hand, in recent years, from the environmental perspective of preventing ozone layer depletion and global warming caused by refrigerants used in refrigerators, air conditioners, etc., liquefied ammonia, liquefied propane, and other hydrocarbon species of liquefied petroleum gas components, which can replace conventional chlorofluorocarbons and alternative chlorofluorocarbons, have attracted attention as "natural refrigerants". Also, for the expansion of the refrigerant function, the use of these mixed systems is assumed, and the liquid-phase and gas-phase phase equilibria of these mixtures are also being studied. For example, the results of evaluating the liquid-phase and gas-phase equilibrium relationships in a binary system of liquefied ammonia and liquefied propane, liquefied propylene, liquefied n-butane, or liquefied 1-butene have been reported (Non-Patent Documents 4 and 5). According to Non-Patent Documents 4 and 5 mentioned above, for a mixture of liquefied ammonia and each hydrocarbon species of the above liquefied petroleum gas components, in the temperature range of about -10 to 20 °C, a vapor-liquid-liquid equilibrium relationship (VLLE) of a heterogeneous azeotropic system is recognized between the two-phase separated liquid phase and gas phase. It is shown that the composition range in which the liquid phase is miscible expands with increasing temperature, and approximate calculations of these vapor-liquid-liquid equilibrium relationships are also shown. Furthermore, for propylene and 1-butene, when the temperature rises above a certain temperature, they become completely miscible with liquefied ammonia at any liquid phase composition (mixing ratio), and it is also shown that a vapor-liquid equilibrium relationship (VLE) of a homogeneous azeotropic system holds between the homogeneous liquid phase and the gas phase.

Prior Art Documents

Non-Patent Documents

[0007]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Non-Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0008] Among the above reports, in Non-Patent Document 1, it is stated that liquefied ammonia can be ignited using light oil as pilot fuel. However, poor ignitability and low flame propagation speed are also recognized at the same time. It is suggested that it is not easy to completely burn the entire amount of ammonia supplied as fuel uniformly and stably with a small amount of light oil as pilot fuel. In addition, since ammonia contains nitrogen elements, especially when combustion does not proceed uniformly and rapidly, there is also a risk of generating a large amount of nitrogen oxides (NOx) including environmentally harmful NO, NO2, and N2O with a high global warming potential. It is also conceivable to improve the combustibility of liquefied ammonia by mixing it with a liquid hydrocarbon fuel such as light oil used as pilot fuel in Non-Patent Document 1. However, since highly polar liquefied ammonia and non-polar liquid hydrocarbons such as light oil are hardly miscible in the liquid phase, it is difficult to mix and burn them uniformly and stably.

[0009] In addition, in Non-Patent Documents 2 and 3, by utilizing the fact that any substances can be uniformly mixed in the gas phase regardless of their polarity, combustion is improved by premixing hydrogen or methane gas as a combustion improver with pre-vaporized ammonia. However, these combustion improvers have significant drawbacks in terms of storage and transportation. Ammonia itself can be easily liquefied by cooling to about -33°C under atmospheric pressure or by pressurizing to about 0.8 MPa at room temperature (25°C), and can be conveniently stored and transported as liquefied ammonia. However, the above-mentioned hydrogen and methane cannot be liquefied unless cooled to extremely low temperatures of about -253°C and -162°C respectively under atmospheric pressure. Liquefaction requires expensive and large-scale cooling equipment, and the energy required for such cooling is also very large. Furthermore, even in the liquefied state, the volumetric energy density of hydrogen is only about 29% of that of gasoline or light oil, and is also 26% lower than that of liquefied ammonia. Near room temperature, neither of them can be liquefied by pressurization (they enter the supercritical state), and the volumetric energy density in these compressed states is even lower than that in the liquefied state. Additionally, the solubility of non-polar methane and hydrogen gas in liquefied ammonia is low, and it is practically impossible to dissolve the amount required for combustion improver in liquefied ammonia. Therefore, when using hydrogen or methane as a combustion improver, separate from the equipment for liquefied ammonia, expensive and large-scale equipment is required for their storage and transportation. Note that Non-Patent Document 2 assumes obtaining hydrogen as a combustion improver by catalytic decomposition of ammonia. In this case, there is no need to store and transport hydrogen itself. However, it is necessary to sequentially produce a predetermined amount of hydrogen as a combustion improver from a part of the ammonia branched from the supply path to combustion in the pre-stage of ammonia combustion. If any problems such as a failure occur in this process, the entire system will be forced to stop. Therefore, this is unlikely to be a highly robust process.

[0010] On the one hand, Non-Patent Documents 4 and 5 show that liquefied ammonia and liquefied petroleum gas components such as liquefied propane are at least partially soluble based on their vapor-liquid equilibrium relationships. It is also stated that these components and their mixtures can be used as "refrigerants" that are less likely to promote ozone layer depletion and global warming even if they themselves leak into the atmosphere. However, the use of these substances as "fuels" that are less likely to produce GHGs such as CO2 even when burned is not at all envisioned in these documents. Furthermore, there is no description or suggestion regarding the possibility of mixing and dispersion under conditions where the mixed liquid phase of liquefied ammonia and liquefied petroleum gas components undergoes phase separation, the requirements for their mixing required for use as fuels, the types of combustion aids that can be used in addition to the above-mentioned liquefied petroleum gas components, etc.

[0011] Therefore, an object of the present invention is to provide an ammonia mixed fuel that can efficiently burn liquefied ammonia while suppressing emissions of GHGs, NOx, etc. by stably mixing and dispersing a combustion aid with high flammability, storability, and transportability with respect to liquefied ammonia. In addition, the present invention provides a manufacturing apparatus for this ammonia mixed fuel, a manufacturing method for the ammonia mixed fuel, and a supply apparatus for the ammonia mixed fuel, as well as a combustion apparatus using this ammonia mixed fuel, a power generation facility using this ammonia mixed fuel, and a transportation device using this ammonia mixed fuel.

Means for Solving the Problems

[0012] One aspect of the present invention is an ammonia mixed fuel, liquefied ammonia, and a combustion aid that assists in the combustion of the ammonia, and the combustion aid is (a) liquefied petroleum gas, naphtha, gasoline, kerosene, and light oil, (b) a hydrocarbon for raw materials that is at least one hydrocarbon species contained as a component in any one of the liquefied petroleum gas, the naphtha, the gasoline, the kerosene, and the light oil, and (c) Alcohol for raw material which is alcohol having 3 or less carbon atoms, and is at least one of The ammonia mixed fuel is in a vapor-liquid equilibrium state, and at least a part of the liquid phase portion of the ammonia mixed fuel is in a solution state in which the ammonia and the combustion aid are dissolved in each other, or in an emulsion state of the ammonia and the combustion aid.

[0013] Another aspect of the present invention is a manufacturing apparatus for manufacturing an ammonia mixed fuel, a sealed container for ammonia storage that stores ammonia in a liquefied state, (a) Liquefied petroleum gas, naphtha, gasoline, kerosene, and light oil, (b) a hydrocarbon for raw material which is at least one hydrocarbon species contained as a component in any one of the liquefied petroleum gas, the naphtha, the gasoline, the kerosene, and the light oil, and (c) alcohol for raw material which is alcohol having 3 or less carbon atoms, and a sealed container for combustion aid storage that stores a combustion aid that aids the combustion of the ammonia, which is at least any one of them. A sealed container for mixing configured to obtain a solution state in which the ammonia and the combustion aid are dissolved by stirring and mixing the ammonia and the combustion aid with a stirrer, or an emulsified mixture, and the mixture obtained by stirring and mixing with the stirrer is configured to maintain a vapor-liquid equilibrium state. An ammonia introduction line provided with an ammonia metering introduction mechanism configured to connect the sealed container for ammonia storage and the sealed container for mixing and introduce a predetermined amount of the ammonia into the sealed container for mixing. A combustion aid introduction line provided with a combustion aid metering introduction mechanism configured to connect the sealed container for combustion aid storage and the sealed container for mixing and introduce a predetermined amount of the combustion aid from the sealed container for combustion aid storage into the sealed container for mixing. and at least one liquid phase discharge line configured to discharge the mixture obtained by stirring and mixing with the stirrer in the sealed container for mixing as an ammonia mixed fuel from the sealed container for mixing.

[0014] Another embodiment of the present invention is a supply device for an ammonia mixed fuel, comprising: a manufacturing device for the ammonia mixed fuel; an ammonia mixed fuel supply line for supplying the ammonia mixed fuel discharged from the mixing sealed container to a combustor configured to burn the ammonia mixed fuel. In this embodiment, the supply device may include a plurality of the combustors. In this case, it is preferable that the supply device includes a plurality of ammonia mixed fuel supply lines so that the ammonia mixed fuel is supplied to each of the combustors.

[0015] Another aspect of the present invention is a combustion device for an ammonia mixed fuel, comprising: a combustor configured to burn the ammonia mixed fuel; a supply device for the ammonia mixed fuel configured to supply the ammonia mixed fuel to the combustor; a combustion gas discharge line configured to discharge combustion gas generated by combustion of the ammonia mixed fuel in the combustor into the atmosphere.

[0016] Another aspect of the present invention is a power generation facility for generating power in any one of land, water, and airspace, comprising: at least one of a combustion device for the ammonia mixed fuel equipped with an internal combustion engine and a combustion device for the ammonia mixed fuel equipped with an external combustion engine is mounted on the power generation facility; a generator configured to generate power using mechanical power extracted by utilizing the energy of the combustion gas of the ammonia mixed fuel; a power output terminal configured to output the power generated by the generator; a control mechanism configured to control the amount of electric power at the power output terminal.

[0017] Another aspect of the present invention is a transportation device configured to perform movement or material transportation in any one of land, water, and air spaces, wherein at least one of a combustion device of the ammonia mixed fuel provided with an internal combustion engine and a combustion device of the ammonia mixed fuel provided with an external combustion engine is mounted, and a power conversion transmission mechanism configured to utilize, as at least part of the power for propulsion of the transportation device, the mechanical power extracted by at least one of the internal combustion engine and the external combustion engine from the energy of the combustion gas of the ammonia mixed fuel.

[0018] Another aspect of the present invention is a transportation device configured to perform movement or material transportation in any one of land, water, and air spaces, wherein the power generation facility is mounted, and at least one of an electric propulsion mechanism and a power supply mechanism configured to use, as at least part of the required power in at least one of propulsion of the transportation device, operation control of the transportation device, and maintenance management of the transportation device, the electric power output from the power generation facility by utilizing the energy of the combustion gas of the ammonia mixed fuel.

[0019] Another aspect of the present invention is a method for manufacturing an ammonia mixed fuel, (1) introducing liquid ammonia and (a) liquefied petroleum gas, naphtha, gasoline, kerosene, and light oil, (b) a hydrocarbon for raw material which is at least one hydrocarbon species contained as a component in any one of the liquefied petroleum gas, the naphtha, the gasoline, the kerosene, and the light oil, and (c) an alcohol for raw material which is an alcohol having 3 or less carbon atoms into a mixing sealed container as a liquid combustion aid for assisting combustion of the ammonia, (2) While maintaining the ammonia and the combustion improver in a gas-liquid equilibrium state with a liquid phase portion remaining in the closed mixing container, they are stirred and mixed so that at least a part of the liquid phase portion of the ammonia and the combustion improver becomes a solution state in which the ammonia and the combustion improver are dissolved in each other, or a mixture in an emulsion state of the ammonia and the combustion improver, (3) Characterized in that the mixture is discharged from the closed mixing container as an ammonia-mixed fuel.

Advantages of the Invention

[0020] According to the above ammonia-mixed fuel, the manufacturing apparatus for the ammonia-mixed fuel, the manufacturing method for the ammonia-mixed fuel, the supply apparatus for the ammonia-mixed fuel, and the combustion apparatus using the ammonia-mixed fuel, it is possible to uniformly and stably mix and disperse a combustion improver having high combustibility, storability, and transportability with respect to liquefied ammonia. As a result, it is possible to efficiently burn liquefied ammonia while suppressing emissions such as GHG and NOx. For this reason, the above ammonia-mixed fuel and the like can be suitably used for power generation facilities and transportation equipment.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

[0022] Hereinafter, an ammonia mixed fuel according to an embodiment, an ammonia mixed fuel production apparatus, an ammonia mixed fuel production method, an ammonia mixed fuel supply apparatus, an ammonia mixed fuel combustion apparatus, a power generation facility using the ammonia mixed fuel, and a transportation device using the ammonia mixed fuel will be described in detail.

[0023] (Ammonia Mixed Fuel) The ammonia mixed fuel according to the embodiment is a fuel containing liquefied ammonia (liquefied ammonia) and an auxiliary fuel. Since liquefied ammonia has the properties of being difficult to ignite and having a low combustion rate, an auxiliary fuel is used to make ammonia easier to ignite and improve the combustion rate. As a combustion improver, (a) liquefied petroleum gas, naphtha, gasoline, kerosene, and gas oil, (b) a hydrocarbon for raw materials (hereinafter also referred to as component hydrocarbon) which is at least one kind of hydrocarbon contained as a component in any one of the liquefied petroleum gas, the naphtha, the gasoline, the kerosene, and the gas oil, and (c) an alcohol for raw materials which is an alcohol having 3 or less carbon atoms, at least one of which is used.

[0024] Here, liquefied petroleum gas (LPG) is generally obtained as a fraction that can be easily liquefied at around normal temperature (25 °C) from by-product gas such as oil fields, natural gas fields, or oil refineries using a compression device and a cooling container. Liquefied petroleum gas contains chain hydrocarbons having 3 and 4 carbon atoms as components. Liquefied petroleum gas can be easily stored and transported after being liquefied, and the gas after vaporization is used as a portable fuel or a propulsion fuel for a moving body equipped with a gas engine. Naphtha corresponds to a fraction having a boiling range of about 30 to 200 °C among the products obtained by distilling and separating crude oil using an atmospheric distillation unit, and its components mainly include chain and alicyclic hydrocarbons (naphthenes) having about 5 to 12 carbon atoms, aromatic hydrocarbons such as benzene, etc. Naphtha is mainly used as a raw material for petrochemical industry and as a raw material for gasoline described later. Naphtha and its component hydrocarbon species can also be used as fuels. Gasoline is a hydrocarbon fuel mainly obtained by purifying and reforming the light fraction of the naphtha, and is a mixture of hydrocarbons having about 5 to 11 carbon atoms, similar to naphtha, and is a petroleum product having a boiling point in the range of about 30 °C to 220 °C and a flash point of -40 °C or lower. Gasoline has an improved octane number by mainly containing aromatic hydrocarbons such as toluene and branched hydrocarbons generated by reforming compared to naphtha, and becomes a fuel that can burn stably particularly in a gasoline engine, and is widely used as a propulsion fuel for moving bodies such as automobiles. Kerosene is a petroleum product mainly composed of chain hydrocarbons with approximately 8 to 15 carbon atoms, corresponding to the fraction with a boiling point in the range of approximately 150 to 280 °C. Products made from kerosene with predetermined purification and addition of anti-freezing components are used not only as heating fuel (kerosene), but also as fuel for jet engines of aircraft, rocket fuel, etc. In this specification, kerosene shall include these products as well. Gas oil is a petroleum product with a boiling point in the range of approximately 180 °C to 350 °C, and its components mainly consist of chain hydrocarbons with approximately 10 to 22 carbon atoms. Gas oil is widely used as a fuel that burns preferably in diesel engines, for thermal power generation, propulsion of large land vehicles, railways, and ships.

[0025] The hydrocarbon raw materials contained in the above liquefied petroleum gas, naphtha, gasoline, kerosene, and gas oil generally mainly consist of straight-chain, branched, or alicyclic saturated hydrocarbons with 3 to 20 carbon atoms, and / or unsaturated hydrocarbons such as alkenes and aromatics. Specifically, the components of liquefied petroleum gas include propane, propylene, n-butane, isobutane, 1-butene, cis-2-butene, trans-2-butene, and isobutene. Naphtha contains, as components, straight-chain and branched saturated hydrocarbons such as n-pentane, isopentane, neopentane, n-hexane, n-octane, and n-decane, straight-chain and branched unsaturated hydrocarbons such as 1-pentene, 1-hexene, and isopentene, alicyclic hydrocarbons such as cyclohexane and cycloheptane, and their isomers, etc. Gasoline mainly contains branched saturated or unsaturated hydrocarbons and aromatic hydrocarbons such as toluene generated by reforming naphtha, excluding straight-chain saturated hydrocarbon components in order to improve the octane number. The components of kerosene and gas oil mainly consist of straight-chain saturated hydrocarbons with a larger molecular weight than the component hydrocarbon species in gasoline. Kerosene mainly contains a series of straight-chain saturated hydrocarbon species centered around n-tridecane and n-tetradecane with 13 to 14 carbon atoms, and gas oil mainly contains n-pentadecane and n-hexadecane with 15 to 16 carbon atoms, etc. The above liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and the hydrocarbon for the above raw materials are generally those obtained from fossil fuels mined in nature or through separation, purification, reforming, etc. from fossil fuels. However, as long as their chemical structures are generally common, as described later, they may be bio-derived extracts or their modified products, or synthetic compounds with generally equivalent components.

[0026] Liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and the hydrocarbon for the above raw materials which are their components can all, as combustion aids, compensate for the difficulty of ignition of ammonia. The ignition point of ammonia is about 650 °C, which is very high even compared to methane (ignition point about 540 °C), a hydrocarbon known for its particularly high ignition point, and it is difficult to catch fire. On the other hand, for example, although there are certain differences depending on the measurer, the ignition points of liquefied petroleum gas (ignition point about 400 °C), naphtha (about 230 - 290 °C), gasoline (about 300 °C), kerosene (about 220 °C), light oil (about 250 °C), and propane (about 430 °C) and n-butane (about 365 °C) which are components of liquefied petroleum gas, cyclohexane (245 °C) which is a component of naphtha, n-hexane (about 220 °C) and toluene (480 °C) which are components of naphtha and gasoline, n-decane (about 210 °C) which is a component of kerosene, and n-hexadecane (about 200 °C) which is a component of light oil are all low, compensating for the difficulty of ignition of ammonia. Also, liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and the hydrocarbon species of these components generally have a higher combustion rate than ammonia (for example, at atmospheric pressure and normal temperature (25 °C), their laminar combustion rates are equal to or higher than that of methane, and all are about 5 - 7 times the laminar combustion rate of ammonia of about 7 cm / s). From the above, by adding these liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and the hydrocarbon for the above raw materials which are their components as combustion aids, the low combustibility of ammonia can be compensated.

[0027] In addition, the alcohols for raw materials include methanol, ethanol, n-propanol, and isopropanol. These alcohols for raw materials also have a lower ignition point compared to ammonia (the ignition points of methanol, ethanol, n-propanol, and isopropanol are approximately 385°C, approximately 384°C, approximately 370°C, and approximately 450°C, respectively), and moreover, all of them have a high combustion rate (about 6 to 7 times that of ammonia in laminar combustion rate), so these can also be used as combustion aids. Also, these alcohols for raw materials, like ammonia, hardly produce so-called soot when burned, so there is also the advantage of easily maintaining the cleanliness inside the combustor (including sliding parts such as in a reciprocating engine) and in the flue during combustion.

[0028] Ammonia mixed fuel, which is a mixture of liquefied ammonia and such a combustion aid, according to the following embodiments of the present invention, at least a part of its liquid phase portion can be in a solution state in which ammonia and the combustion aid are mutually dissolved, or in an emulsion state of ammonia and the combustion aid. For example, when liquefied ammonia is mixed with liquefied petroleum gas in a liquid state or hydrocarbon species of its components as a combustion aid in a sealed space, there is a thermodynamic gas-liquid equilibrium relationship (the phase equilibrium relationship between the gas phase and the liquid phase (two-phase separation or miscibility), the gas-liquid two-phase or gas-liquid-liquid three-phase) between ammonia and liquefied petroleum gas as each hydrocarbon species of the components or a mixture thereof, as will be described later. Based on this relationship, although there are differences depending on the component hydrocarbon species, simply mixing these with liquefied ammonia will result in at least partial miscibility and a thermodynamically stable state for all of them. Furthermore, if the temperature is raised, the proportion of the part of these combustion aids that is miscible with ammonia will be increased further, and even complete mixing can be achieved. Also, by further adding a suitable surfactant (an example of its form will be shown later), at least a part of the remaining portion of these combustion aids that could not be dissolved by simple mixing at a predetermined temperature can be homogenized in an emulsion state at that temperature. In addition, when naphtha, gasoline, kerosene, gas oil, etc. containing hydrocarbon species with 5 or more carbon atoms as components and these component hydrocarbon species are used as combustion aids, as will be described later, the thermodynamic gas-liquid equilibrium relationship (the phase equilibrium relationship between the gas phase and the liquid phase (two-phase separation or miscibility), i.e., the gas-liquid two-phase or gas-liquid-liquid three-phase equilibrium relationship) holds, and ammonia can be dissolved under the gas-liquid equilibrium conditions in a closed space. For example, naphtha containing a large amount of branched-chain hydrocarbon species, alicyclic hydrocarbon species, and aromatic hydrocarbons such as benzene, which have higher dispersibility than linear hydrocarbon species, has relatively high compatibility with ammonia. Also, in addition to branched-chain hydrocarbon species, gasoline containing a large amount of aromatic hydrocarbon species that are nonpolar or low-polar but have large induced dipoles has high compatibility with liquefied ammonia (see Example 14 described later). For example, benzene, and toluene, o,m,p-xylene, etc., which are aromatic hydrocarbon species contained in a large amount as components in commercially available gasoline, are completely miscible with liquefied ammonia regardless of the mixing ratio near room temperature (25°C), similar to the aforementioned methanol. Also, by adding a suitable surfactant described later, at least a part of it can be further solubilized in an emulsion state, similar to the case of liquefied petroleum gas and its component hydrocarbon species. As a result, the combustibility of the entire mixed fuel is improved more uniformly. When ammonia and these combustion aids are in a solution state or an emulsion state, they vaporize during combustion, and a situation occurs where vaporized ammonia is mixed in the immediate vicinity of these combustion aids that have ignited. As a result, the vaporized ammonia is inductively ignited and the combustion rate is also improved, so that overall, good, simultaneous, and uniform combustion can be achieved. In addition, the alcohol for the raw material having 3 or less carbon atoms is a liquid having a polarity similar to that of liquefied ammonia at around normal temperature (25°C) and atmospheric pressure. Since they have high affinity due to the effect of hydrogen bonds acting between their molecules, they are miscible with liquefied ammonia in a wide composition range. Furthermore, in the mixture of liquefied ammonia and the alcohol for the raw material, hydrogen bonds are formed between the molecules of both, suppressing the vaporization of ammonia. Therefore, the saturated vapor pressure of their mixed solution is lower than the saturated vapor pressure of ammonia alone at the same temperature. This means that when storing the solution of liquefied ammonia and the alcohol for the raw material, the pressure resistance of the storage container during storage near normal temperature (25°C) and the energy required for cooling during cooling and liquefaction near atmospheric pressure can be significantly reduced compared to the case of ammonia alone, which is a great advantage in storage and transportation. That is, it has excellent storability and transportability. Also, during combustion, since ammonia and the alcohol for the raw material are in a solution state, extremely uniform mixed gases are generated after vaporization, similar to the case of mixing with the above hydrocarbon species. In addition, the alcohol for the raw material dissolved in ammonia acts as an auxiliary fuel, so the ignition point is lowered, the ignitability is improved, and the combustion rate is also improved, resulting in improved combustibility compared to the case of ammonia alone. However, among these alcohols for the raw material, ethanol is known to react and decompose with ammonia in the solution gradually, increasing the risk of fire and the like. Therefore, for ammonia mixed fuels containing ethanol, it is preferable that they are not stored for a long time after production and are burned and consumed quickly as fuel unless additives or the like that suppress such reactions are added.

[0029] The mass ratio of ammonia to the combustion improver can be appropriately determined according to the application target and purpose of the mixed fuel. For example, when replacing a part of hydrocarbon fuels such as liquefied petroleum gas, naphtha, gasoline, kerosene, and light oil and their component hydrocarbon species with liquefied ammonia (for example, the ammonia content is approximately 1% by mass or more and 20% by mass or less) and aiming to suppress the generation of CO2 during combustion, the mass of these combustion improvers is relatively more than the mass of ammonia. In such a composition ratio, within a sealed space in a temperature range of approximately 50°C or less close to room temperature (25°C), liquefied ammonia and the combustion improver can dissolve most of their parts, or can be emulsified by adding a suitable surfactant described later. Such a mixed fuel with such a mass ratio is advantageous when continuously using existing combustion devices such as combustors, burners, internal combustion or external combustion engines that were previously used with hydrocarbon fuels while suppressing certain GHG emissions. Conversely, it is also possible to use a mixed fuel mainly composed of liquefied ammonia and relatively containing a small amount of the above-mentioned hydrocarbon fuels, their component hydrocarbon species, and the alcohol for raw materials as a combustion improver (for example, when the ammonia content is approximately 80% by mass or more and 99% by mass or less). Also in such a mass ratio, within a temperature range of approximately 50°C or less close to room temperature (25°C), liquefied ammonia and the combustion improver can dissolve most of their parts with respect to the total volume, or can be emulsified by adding a suitable surfactant described later. When using such a mixed fuel mainly composed of liquefied ammonia, GHG emissions can be suppressed more significantly.

[0030] In addition, when the combustion improver is liquefied petroleum gas, naphtha, gasoline and its component hydrocarbon species, or alcohol for raw materials having 3 or less carbon atoms, since the mixing and dispersibility with liquefied ammonia is high, even if the ammonia content is a mixed fuel of approximately 20 to 80% by mass, which is intermediate between the above two cases shown by the mass ratio, in the temperature range from around room temperature (25°C) to approximately 50°C, by stirring, most of its total volume can be made compatible, or it can be emulsified by adding a suitable surfactant described later. On the other hand, when the combustion improver is kerosene, light oil, and their component hydrocarbon species, in the temperature range from around room temperature (25°C) to approximately 50°C, since the mixing and dispersibility with liquefied ammonia is low, at a mixing ratio where the mass ratio with the combustion improver is approximately 20 to 80% by mass, even when using the suitable surfactant described later, the required addition amount becomes extremely large (for example, a corresponding amount of approximately 10% by mass or more is required) in order to uniformly disperse the whole as an emulsion. Also, it becomes difficult to sufficiently disperse a large amount of surfactant. Therefore, in such a mixed composition, in practice, it is inevitable that a part where liquid phase separation occurs remains (for this reason, it is dealt with by limiting the addition amount of either liquefied ammonia or the combustion improver within the upper limit amount that can be solubilized or emulsified). However, if the suitable surfactant described later is used, by adding up to approximately 5% by mass at most, even if the liquid phase separates, in the ammonia side phase where combustion is inferior among the two separated phases, the combustion improver (kerosene, light oil, and their component hydrocarbon species) can be emulsified and dispersed up to approximately 10% by mass, so the combustibility of such an ammonia side phase in which the combustion improver is dispersed is improved compared to when liquefied ammonia is alone. Note that the other phase among the liquid phase separated phases mainly consists of the combustion improver, so its combustibility is high. As described later, if kerosene and its component hydrocarbon species are heated to approximately 50 to 100°C, and if light oil and its component hydrocarbon species are heated to approximately 80 to 130°C, even without adding a surfactant, they can be made compatible with liquefied ammonia in a wide range of mixing ratios (at approximately 130°C or higher, the mixture becomes a subcritical or supercritical state and becomes compatible). In the combustion improver for the ammonia mixed fuel described above, even when both the hydrocarbon for raw materials and the alcohol for raw materials are included, the mass ratio of each is appropriately determined according to the application target and purpose of the mixed fuel.

[0031] In the ammonia mixed fuel, the larger the proportion of the mixed solution state or the emulsion state in the total amount, the better. If possible, it is preferably maintained as it is after production as an equilibrium stable composition. By these means, the overall combustibility of the ammonia mixed fuel can be improved more uniformly. Also, when such an ammonia mixed fuel is sent through a piping system, if the liquid phase is separated into two phases, each phase is separated into layers in the vertical direction in the piping system due to the specific gravity difference between the phases, and any one of the phases is likely to stay in the stagnant part in the piping system. As a result, a situation may occur where the composition of the ammonia mixed fuel deviates at the liquid delivery outlet. However, the larger the proportion of the mixed solution state or the emulsion state in the total amount, the easier it is to prevent such a situation where the composition deviates. In particular, when the combustion improver added to ammonia is liquefied petroleum gas, naphtha, gasoline, and their component hydrocarbon species, and the alcohol for raw materials, which can be quite compatible with each other to a certain extent by the equilibrium relationship without adding a surfactant, once the part that has become compatible, as long as the temperature at the time of dissolution is maintained and the gas-liquid equilibrium state is maintained, it continues to be permanently compatible as a thermodynamically stable solution state (however, as described above, when the combustion improver contains ethanol, the reaction with ammonia gradually progresses). Also, the longer the time the emulsion state formed after mixing and dispersion is stably maintained, the better. As a guideline for storage and use as a fuel, the stable maintenance time is at least about 5 minutes, preferably several days, and more preferably about 1 month or more. In particular, when a mixed fuel in an emulsion state is prepared by adding a sufficient amount of a suitable surfactant described later and stirring at an appropriate temperature, once the emulsion is formed, as long as the temperature at the time of dissolution is maintained and the gas-liquid equilibrium state is maintained, it maintains a thermodynamically metastable state, so that its dispersed state can be maintained over a long period of one day to several days, or about 1 month or more. When the ammonia mixed fuel is in a transient emulsion state of non-equilibrium and the components are phase-separated during storage, it is advisable to remix and stir it again to return it to the emulsion state before supplying the ammonia mixed fuel to the combustor. At that time, if necessary, appropriate temperature control should be carried out as described later. By doing so, the combustion advantages of the ammonia mixed fuel can be restored. Furthermore, the ammonia mixed fuel is preferably maintained at a predetermined temperature according to the liquid phase composition such that the entire liquid phase portion of the ammonia mixed fuel is in a solution state in which ammonia and the combustion aid are dissolved in each other, or in an emulsion state of ammonia and the combustion aid. As described later, the ammonia mixed fuel can be configured such that the composition and temperature of its constituent components are maintained within an appropriate composition and an appropriate temperature range corresponding to the composition, or by adding a sufficient amount of a suitable surfactant described later and mixing and dispersing them, at least one of the following can be achieved: making the entire liquid phase portion of the ammonia mixed fuel into a solution state in which ammonia and the combustion aid are dissolved in each other, or making it into an emulsion state of ammonia and the combustion aid. By maintaining the entire liquid phase portion of the ammonia mixed fuel in a solution state in which ammonia and the combustion aid are dissolved in each other, or in an emulsion state of ammonia and the combustion aid, the overall combustibility of the ammonia mixed fuel can be improved uniformly and to the highest degree.

[0032] In particular, for ammonia (which contains no carbon at all), liquefied petroleum gas, and alcohols for raw materials with 3 or fewer carbon atoms, the CO2 emissions per unit of calorific value are less than those of gasoline, kerosene, light oil, heavy oil, coal, etc., which have been conventionally used as fossil fuels. Therefore, the ammonia mixed fuel mixed with these as combustion aids is itself a very effective fuel for suppressing the emission of greenhouse gases (GHGs) such as CO2. In addition, hydrocarbon species having a structure equivalent to that of the aforementioned liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and hydrocarbon raw materials for these components, and alcohol for raw materials having 3 or less carbon atoms excluding ethanol, may be produced by chemical synthesis via reduction of industrial exhaust gas or CO2 separated and collected from the atmosphere into CO, methane, etc. using renewable energy such as sunlight, wind power, hydraulic power, geothermal energy, etc., electricity obtained by nuclear power, or hydrogen obtained by electrolysis of water using such electricity. For such hydrocarbon raw materials and the aforementioned alcohol for raw materials produced based on renewable energy, unlike the case of fossil fuels, even if they are burned and exhaust gas is released into the atmosphere, CO2 emissions are considered to be substantially suppressed. Also, many of the hydrocarbon species having a structure equivalent to these and alcohol for raw materials having 3 or less carbon atoms including methanol and ethanol are known to be synthesizable from raw materials such as metabolites of plants and microorganisms that perform photosynthesis. When such products based on photosynthesis or metabolites are used as a combustion aid, since the carbon contained therein is derived from CO2 in the atmosphere, it is considered that even if burned, it does not substantially increase the CO2 in the atmosphere. Therefore, the use of an ammonia mixed fuel in which a combustion aid based on the above-mentioned renewable energy and a bio-derived combustion aid based on photosynthesis are mixed can highly suppress global warming.

[0033] The ammonia mixed fuel is preferably stored in isolation within a sealed environment in which the gas-liquid equilibrium is maintained from the viewpoints of storage and transportation so that the fuel can be stably supplied in a liquefied state.

[0034] The ammonia mixed fuel of one embodiment preferably contains at least one of the aforementioned liquefied petroleum gas, the aforementioned hydrocarbon for raw materials, and the aforementioned alcohol for raw materials as a combustion aid, and the aforementioned hydrocarbon for raw materials is at least one hydrocarbon species contained as a component in the aforementioned liquefied petroleum gas, and the alcohol for raw materials is methanol. That is, the ammonia mixed fuel preferably contains at least one of liquefied petroleum gas, at least one hydrocarbon contained as a component in liquefied petroleum gas, and methanol as a combustion aid. Liquefied petroleum gas and hydrocarbon species contained therein as its constituents have conventionally been preferred in terms of generating less CO2 per unit of calorific value during combustion, compared to gasoline, kerosene, light oil, or heavy oil, which have been widely used as liquid fuels. As described above, liquefied petroleum gas and hydrocarbon species contained therein as its constituents have a saturation vapor pressure relatively close to that of ammonia in the liquid state at the same temperature, and have a lower ignition temperature than lower molecular weight hydrocarbons such as methane, making them easier to ignite. Also, they have a combustion rate equal to or higher than that of methane, about 5 to 6 times that of ammonia, and are advantageous as a combustion aid for ammonia. Therefore, when liquefied petroleum gas or its component hydrocarbon species and ammonia are in a solution state or an emulsion state, during combustion, they are very uniformly mixed and vaporize almost simultaneously and uniformly, and the vaporized mixed gas is easily heated simultaneously and uniformly. For this reason, when the liquefied petroleum gas or its component hydrocarbon species such as propane vaporize and then ignite in a combustor, the vaporized ammonia mixed very close to the gas of the liquefied petroleum gas or its component hydrocarbon species is heated and ignited, and overall, particularly good simultaneous and uniform combustion can be achieved.

[0035] Among the liquid fossil fuels that have been widely used as fuels, kerosene, gas oil, and hydrocarbon species of these components, excluding gasoline, mainly consist of non-polar straight-chain saturated hydrocarbons with approximately 8 or more carbon atoms. Generally, a mixture of such non-polar straight-chain saturated hydrocarbon species with approximately 8 or more carbon atoms and liquefied ammonia is hardly miscible and separates into two phases in a temperature range from around room temperature (25°C) to approximately 50°C under its vapor-liquid equilibrium conditions. In order to dissolve these without adding a surfactant described later, it is necessary to heat them to a higher temperature (for example, approximately 50 to 100°C for kerosene and its hydrocarbon components, and approximately 80 to 130°C for gas oil and its hydrocarbon components) compared to liquefied petroleum gas and its component hydrocarbon species. At this time, since the saturated vapor pressure mainly governed by the vaporization properties of ammonia increases (for example, approximately 3 to 4 MPa or more), high pressure resistance is required for the manufacturing equipment during the production and storage of the mixed fuel. Therefore, in order to supply such non-polar straight-chain saturated hydrocarbons with approximately 8 or more carbon atoms and liquefied ammonia to combustion in a stably and precisely mixed state, generally, emulsification by adding and mixing a predetermined surfactant as described later is necessary. On the other hand, for the eight types of hydrocarbons with 3 and 4 carbon atoms (propane, propylene, n-butane, isobutane, 1-butene, cis-2-butene, trans-2-butene, and isobutylene), which are the main components of liquefied petroleum gas, although all are non-polar, they are uniformly miscible with highly polar liquid ammonia in almost any composition range under the vapor-liquid equilibrium conditions in a sealed space at a predetermined temperature where the temperature is approximately 40°C or lower and the saturated vapor pressure is approximately 2 MPa or lower without adding a surfactant. Regarding the miscibility of such ammonia and low-molecular-weight hydrocarbons and the related vapor-liquid equilibrium relationship, Non-Patent Documents 4 and 5 regarding the mixing properties of ammonia and low-molecular-weight hydrocarbons as refrigerants show one end of them. Hereinafter, based on the data described in Non-Patent Documents 4 and 5, taking the cases where propane and n-butane, which are the main components of liquefied petroleum gas, are used as combustion aids as examples, the situations where the above-mentioned liquefied ammonia and combustion aid are in a miscible solution state and the emulsified state will be described.

[0036] Figure 1(a) and (b) illustrate the vapor-liquid-liquid equilibrium (VLLE) relationships of ammonia-propane and ammonia-n-butane systems, respectively, as described in Non-Patent Documents 4 and 5 (in Figure 1(a) and (b), the ammonia concentrations (x, y) in the liquid and vapor phases are converted from the mole fraction representation used in Non-Patent Documents 4 and 5 to mass % representation). Figure 1(a) shows the relationship between the vapor-liquid composition and the saturation vapor pressure in the vapor-liquid-liquid equilibrium (VLLE) of the ammonia-propane heterogeneous azeotropic system at 20°C (upper) and 0°C (lower). The solid lines in the figure (the trajectories of PABQ at 20°C and P’A’B’Q’ at 0°C) represent the relationship between the liquid-phase composition (x) and the saturation vapor pressure (p) (liquidus line), and the dashed lines below it (the trajectories of POQ at 20°C and P’O’Q’ at 0°C) represent the relationship between the vapor-phase composition (y) in equilibrium with the liquid phase and the saturation vapor pressure (p) (vaporus line). At 20°C, starting from point P where the vapor-liquid equilibrium of pure propane is shown with vapor-liquid compositions x, y = 0, as the ammonia concentration in the liquid phase increases until point A where the dissolution of ammonia becomes saturated (ammonia concentration x A = 16.2 mass %), ammonia continues to dissolve uniformly in the propane-based liquid phase, and the saturation vapor pressure increases while maintaining the liquid-phase single-phase state. When the ammonia concentration in the liquid phase reaches the saturation concentration x A at point A (at this time, the vapor phase reaches point O where the saturation vapor pressure is maximum (azeotropic point: vapor-phase ammonia concentration y O = 31.2 mass %, saturation vapor pressure p O = 1.64 MPa)), the ammonia concentration in the propane-based liquid phase mentioned above does not increase any further, and another liquid phase mainly composed of ammonia that is phase-separated from the said phase appears. In this phase-separated liquid phase mainly composed of ammonia, propane is saturatedly dissolved (ammonia concentration x B = 86.5 mass %, propane concentration (saturated) 1 - x B = 13.5 mass %). Between the liquid-phase composition from x A to x B (on the line segment AB of the liquidus line), the propane-based liquid phase with ammonia concentration x A and the liquid phase mainly composed of ammonia with ammonia concentration xB A two-phase, phase-separated liquid phase mainly composed of ammonia coexists, and during this, the gas phase has an ammonia concentration y that is in equilibrium with this O and a saturation vapor pressure p O is maintained in the azeotropic state (point O). Also, at point C (ammonia concentration x C ) on line segment AB in the region where the liquid phase undergoes two-phase separation, the mass ratio of the propane-based phase with ammonia concentration x A and the ammonia-based phase with ammonia concentration x B is represented by (x B -x C ):(x C -x A ) according to the "lever principle". When the ammonia concentration in the liquid phase increases beyond x B (point B on the liquidus line), the above-mentioned propane-based phase disappears, and the liquid phase becomes only a single phase mainly composed of ammonia in which propane is dissolved. Further increasing the ammonia concentration in this phase, it reaches point Q in the figure showing the vapor-liquid equilibrium of pure ammonia while remaining a single phase through the locus of BQ on the liquidus line. The composition of the gas phase and the saturation vapor pressure in equilibrium with this trace the locus of OQ on the gas phase line, and as the ammonia concentration in the gas phase increases, the saturation vapor pressure decreases until point Q. Since the above behavior is based on the thermodynamic equilibrium relationship, operating in the direction of decreasing the ammonia concentration from the Q-point side showing the vapor-liquid equilibrium of pure ammonia will result in the same situation.

[0037] From the above, at 20 °C, in the above-mentioned liquid phase mainly composed of propane, ammonia can be thermodynamically stably dissolved up to its saturation concentration of x A (= 16.2 mass%) without phase separation through the locus of PA in Fig. 1(a). Also, in the above-mentioned liquid phase mainly composed of ammonia, propane can be dissolved up to its saturation concentration of 1 - x BUp to [[ID=]], it can be dissolved stably thermodynamically without phase separation. Assuming a mixed fuel at 20 °C in which liquefied propane is dissolved as a combustion improver in liquefied ammonia, the liquid phase mainly composed of propane among the above two liquid phases corresponds to the case where the amount of liquefied propane as the combustion improver is significantly larger than that of liquefied ammonia. When a part of liquefied propane (here, 16.2 mass% or less) is replaced by ammonia and taken out as a mixed fuel for combustion, it becomes a single-phase miscible mixed fuel that burns uniformly as a whole, and due to the above replacement, the generation of CO2 can be suppressed compared to the case of the single combustion of liquefied propane. Further, the liquid phase mainly composed of ammonia among the above two liquid phases corresponds to the case where the amount of liquefied propane as the combustion improver is smaller than that of liquefied ammonia. When a part of liquefied ammonia (here, 13.5 mass% or less) is replaced by propane and taken out as a mixed fuel for combustion, it becomes a single-phase miscible mixed fuel that burns uniformly as a whole, and due to the above replacement, the combustibility can be improved compared to the case of the single combustion of liquefied ammonia. Also, in the gas-liquid-liquid equilibrium relationship at 20 °C in Fig. 1(a), the liquid ammonia concentration x at point C C at which the liquid phase separates into two phases (at this time, due to the specific gravity difference, the upper layer is the phase mainly composed of propane (ammonia concentration x A = 16.2 mass%), and the lower layer is the phase mainly composed of ammonia (ammonia concentration x B= 86.5% by mass). At this time, as shown in the figure, when point C is close to point B, according to the above-mentioned "lever principle", the mass of the liquid phase mainly composed of propane is relatively small compared to the mass of the liquid phase mainly composed of ammonia. When the total amount is taken out as a mixed fuel and used for combustion, due to phase separation, the combustion uniformity of the mixed fuel is inferior to that of the above-mentioned single-phase miscible mixed fuel. However, the liquid phase mainly composed of propane with a small amount of phase separation also has high flammability originally, so it can be burned well as a whole. On the other hand, when point C is close to point A and the total amount is taken out as a mixed fuel and used for combustion, the combustion uniformity of the mixed fuel is inferior to that of the above-mentioned single-phase miscible mixed fuel. However, the liquid phase mainly composed of ammonia with a small amount of phase separation also has a combustion-supporting effect because propane is saturated and dissolved at a concentration of 1 - x B (= 13.5% by mass), so it can be burned well as a whole. Also, as described later, if the upper layer and / or the lower layer separated into two phases can be taken out as mixed fuels separately and each layer can be used for combustion separately, since each layer itself becomes a single-phase mixed fuel, each shows uniform and good combustibility.

[0038] In the gas-liquid-liquid equilibrium relationship of the ammonia - propane system at 0°C shown below in Fig. 1(a), the liquid phase line is represented by the locus of P’A’B’Q’, and the gas phase line is represented by the locus of P’O’Q’. At 0°C, compared with the case at 20°C, the two-phase separation region (between A’B’ on the liquid phase line) in the liquid phase expands, and the single-phase regions (between P’A’ and between B’Q’ on the liquid phase line) on both sides shrink. Also, including the azeotropic vapor pressure p O’ (= 0.66 MPa), the saturated vapor pressure generally decreases compared with that at 20°C. The shrinkage of the single-phase regions (between P’A’ and between B’Q’ on the liquid phase line) indicates that the compatibility between liquefied ammonia and liquefied propane decreases due to the decrease in temperature. Therefore, when using this system as a single-phase miscible mixed fuel at 0°C, ammonia can be present in the liquid phase mainly composed of propane at a concentration of x A’ (= 6.7% by mass), and propane can be present in the liquid phase mainly composed of ammonia at a concentration of 1 - x B’Up to (= 6.5% by mass), they can each be dissolved, but their solubilities are lower compared to those at 20°C. Also, Fig. 1(b) shows the relationship between the gas-liquid composition and the saturation vapor pressure in the vapor-liquid-liquid equilibrium (VLLE) of the ammonia-n-butane system at 0°C. For comparison with the ammonia-propane system, the symbols (P’, A’, B’, Q’, O’, etc.) in this figure are the same as the corresponding symbols in the ammonia-propane system at 0°C in Fig. 1(a). In the vapor-liquid-liquid equilibrium relationship of the ammonia-n-butane system at 0°C in Fig. 1(b), the liquid phase line (the locus of P’A’B’Q’) represented by the solid line and the gas phase line (the locus of P’O’Q’) represented by the dashed line can also be recognized. Qualitatively, it is common with the vapor-liquid-liquid equilibrium of the ammonia-propane system in Fig. 1(a). That is, when this system is used as a single-phase miscible mixed fuel at 0°C, ammonia can be present in the liquid phase mainly composed of n-butane at a concentration of x A’ (= 5.2% by mass), and n-butane can be present in the liquid phase mainly composed of ammonia at a concentration of 1 - x B’ (= 2.7% by mass), and they can each be dissolved. Also, reflecting the lower volatility of n-butane compared to propane, the saturation vapor pressure, including the azeotropic vapor pressure p O’ (= 0.53 MPa) at the azeotropic point O’, is generally lower compared to the ammonia-propane system. Despite the above differences, in the vapor-liquid equilibrium relationship of the ammonia-n-butane system, in terms of having a temperature and composition region where the liquid phase undergoes two-phase separation, it is qualitatively common with the vapor-liquid equilibrium relationship of the aforementioned ammonia-propane system.

[0039] Generally, not only propane and n-butane described above, but also each component hydrocarbon species of other liquefied petroleum gases shows qualitatively the same relationship of vapor-liquid-liquid equilibrium (VLLE) of a heterogeneous azeotropic system in each predetermined temperature range. Also, with the increase in relative temperature, for example, the interval between point A and point B (or point A' and point B') on the liquidus line shown in Fig. 1(a) approaches, the two-phase separation region shrinks, and the compatibility increases. Further, above each predetermined temperature (critical miscibility temperature), point A (or point A') and point B (or point A') converge to the azeotropic point O (or point O'), and the two-phase separation region in the liquid phase disappears. That is, it is known that each component hydrocarbon species of liquefied petroleum gas becomes completely miscible in the liquid phase with liquefied ammonia at any composition ratio above the above critical miscibility temperature. Among the component hydrocarbon species of liquefied petroleum gas, when compared at the same temperature, those with 3 carbon atoms (propane, propylene) and those with double bonds (propylene, various butenes) are relatively more compatible with liquid ammonia than the component hydrocarbons outside their respective categories. For example, regarding the above critical miscibility temperature, it is about 33°C for propane, a saturated straight-chain hydrocarbon with 3 carbon atoms, and about 38°C for n-butane, a straight-chain saturated hydrocarbon with 4 carbon atoms. In temperature ranges above these, it has been confirmed that they are miscible with ammonia in the liquid phase at any composition ratio. Also, in Non-Patent Documents 4 and 5, it has been reported that propylene, an unsaturated straight-chain hydrocarbon with 3 carbon atoms, is miscible with ammonia in the liquid phase at 0°C, and 1-butene, an unsaturated straight-chain hydrocarbon with 4 carbon atoms, is miscible with ammonia in the liquid phase at 10°C regardless of the composition (however, it is not specified whether these temperatures are the critical miscibility temperature). In the temperature range above the critical miscibility temperature of each of these component hydrocarbon species of liquefied petroleum gas, a relationship of vapor-liquid equilibrium (VLE) of a homogeneous azeotropic system is established between the completely miscible liquid phase of these and ammonia and the vapor phase. Also, for example, the liquid phase composition (ammonia concentration x) at point C in the vapor-liquid-liquid equilibrium relationship of the ammonia-propane system at 20°C in Fig. 1(a) C) In [the situation described above], as mentioned before, at 20°C, the liquid phase undergoes phase separation. However, even at the liquid phase composition at point C, there must exist a predetermined temperature that is higher than 20°C and lower than the above-mentioned critical miscibility temperature (about 33°C), at which ammonia and propane are completely miscible. For example, in the equilibrium relationship between ammonia and propane at 20°C in Fig. 1(a), the liquid ammonia concentration x C corresponding to the position of C ≒ 77 mass% (at this time, the overall average composition of the combined liquid and gas phases, i.e., the ammonia concentration of the charged composition, becomes about 75 mass% corresponding to the conditions of Example 1 described later), if it is approximately 23°C or higher, it will become a homogeneous solution without phase separation (i.e., at 23°C, point B and point C overlap, and the ammonia concentration x B corresponding to point B, which is the saturated state of propane, becomes about 77 mass%. See Example 1 described later). Such behavior is similarly observed for all component hydrocarbon species of liquefied petroleum gas other than propane. That is, in a mixed fuel of liquefied petroleum gas or a component hydrocarbon species of liquefied petroleum gas and ammonia, by maintaining the temperature of the mixed fuel above the above-mentioned temperature corresponding to the liquid phase composition of the mixed fuel, the entire liquid phase portion of the mixed fuel can be made to be in a solution state in which ammonia and the combustion improver are dissolved in each other (see Example 2 described later (when the combustion improver is n-butane)). As a result, when taking out the entire amount as a mixed fuel and using it for combustion, the effect of the combustion improver can be maximally exhibited, and the mixed fuel can be burned extremely uniformly.

[0040] In the above-mentioned mixed system of liquefied ammonia and component hydrocarbon species of liquefied petroleum gas, the saturated vapor pressures in the gas-liquid-liquid equilibrium and gas-liquid equilibrium are generally higher than the respective saturated vapor pressures of liquefied ammonia and component hydrocarbon species of liquefied petroleum gas alone at the same temperature. In addition, for a single-phase miscible mixed fuel of liquefied petroleum gas hydrocarbon species other than propane, or even liquefied petroleum gas which is a mixture of them, and liquefied ammonia, similar to the case of propane described above, the hydrocarbon species of the liquefied petroleum gas dissolved in the liquefied ammonia form a uniform mixed gas with ammonia after vaporization and act as an oxygenating agent in that state. Therefore, compared with the case of liquefied ammonia alone, the ignition point is lowered, the ignitability is improved, and the combustion rate also increases, resulting in improved combustibility. On the other hand, even under the mixing composition and temperature conditions where phase separation occurs and the liquefied ammonia cannot be completely miscible, in the liquid phase mainly composed of liquefied ammonia generated by the phase separation, the liquefied petroleum gas components are saturated and dissolved as an oxygenating agent. Also, in the other liquid phase mainly composed of the hydrocarbon species of the liquefied petroleum gas, since the main component hydrocarbon species themselves originally have good combustibility, good combustion can be achieved as a whole. Furthermore, if each of the phase-separated phases is taken out as a separate mixed fuel and each is separately used for combustion, each will become a uniform single phase and exhibit good combustibility.

[0041] Methanol can also be used as a fuel that suppresses the generation of GHG, similar to liquefied petroleum gas or its components. Methanol also has a low ignition point of about 385°C, making it easy to ignite. Its laminar burning velocity is also about 45 cm / s, which is 6 to 7 times higher than that of ammonia, making it easy to burn and suitable as an oxidizer for ammonia. Also, compared to heavy oil, light oil, kerosene, and gasoline, which have been widely used as liquid fuels in the past, the CO2 generation per unit of calorific value during combustion is less. Furthermore, methanol can be uniformly mixed (completely dissolved) in a liquid state with liquefied ammonia in any composition without the addition of a surfactant in at least the temperature range of about 0 to 40°C. Similar to liquefied petroleum gas or its main components, vaporized ammonia that is present very close to the ignited methanol after vaporization can be heated and ignited, enabling particularly good and simultaneous uniform combustion as a whole. Also, like ammonia, methanol is less likely to produce so-called soot during combustion, which has the advantage of easily maintaining the cleanliness inside the combustor and the flue. Different from the case of a mixed system of liquefied ammonia and liquefied petroleum gas or its component hydrocarbon species, the mixture of liquefied ammonia and methanol exhibits a liquid-phase complete miscibility non-azeotropic gas-liquid equilibrium regardless of the liquid-phase composition. Therefore, if this is taken out as a mixed fuel and used for combustion at any composition ratio, uniform and good combustion is possible. Furthermore, in a solution of liquefied ammonia and methanol, a hydrogen bond is formed between the molecules of the two, suppressing the vaporization of ammonia. Therefore, the saturated vapor pressure of these mixed solutions is significantly lower than the saturated vapor pressure of ammonia alone at the same temperature (see Example 13 described later). This means that when storing the mixed fuel of liquefied ammonia and methanol, the pressure resistance of the storage container during storage near room temperature (25°C) and the energy required for cooling during cooling and liquefied storage near atmospheric pressure can be significantly reduced compared to the case of ammonia alone, which is a great advantage in storage and transportation.

[0042] Also, ammonia, liquefied petroleum gas or its component hydrocarbon species, and methanol, which are the raw materials for the ammonia mixed fuel, are also excellent in terms of raw material procurement. That is, ammonia has mainly been synthesized in large quantities worldwide by the Haber-Bosch process using methane, the main component of natural gas, as a raw material. For this reason, ammonia large-scale synthesis plants are often built near natural gas fields around the world. The extraction of natural gas with a high methane content, which is the raw material for ammonia, is mainly carried out by separating hydrocarbons with higher boiling points from the raw gas extracted from the gas field by liquefying them through pressurization or cooling. In addition to liquefied petroleum gas, naphtha components are generally included in these components with higher boiling points. These are separated from each other in the same natural gas purification plant and become products respectively. Therefore, in ammonia production plants using natural gas as a raw material, liquefied petroleum gas is often co-produced in the vicinity in many cases. For this reason, when an ammonia mixed fuel is also incidentally produced in an ammonia production plant, hydrocarbons such as liquefied petroleum gas and its components propane, n-butane, etc., which are added as a combustion improver to the above ammonia mixed fuel, are advantageous in terms of raw material procurement in production.

[0043] Also, methanol is similarly mass-produced using methane, the main component of natural gas, as a raw material. The initial processes of methanol synthesis from methane are the desulfurization process and the steam reforming process (CH4 + 2H2O → 4H2 + CO2, and CH4 + H2O → 3H2 + CO), which are the same as the initial processes of ammonia production by the Haber-Bosch process from the above-mentioned natural gas raw material. For this reason, the co-production of ammonia and methanol in the same production plant is advantageous in terms of both suppressing CO2 emissions to the environment by effectively using carbon in natural gas (utilizing carbon, which is a component element in natural gas excluded in ammonia production, in methanol production) and improving efficiency by commonalizing processes. In fact, large-scale production plants that co-produce both have also been built in recent years. Therefore, in ammonia production plants using natural gas as a raw material, methanol can also be co-produced advantageously. For this reason, when an ammonia mixed fuel is also incidentally produced in an ammonia production plant, methanol, as a combustion improver contained in the ammonia mixed fuel, is also advantageous in terms of raw material procurement in production.

[0044] Furthermore, when assuming that ammonia is to be transported in large quantities by transportation equipment from its large-scale production bases to demand areas of large-scale consumption far away, it is preferable in terms of efficiency and cost that the fuel for propulsion of the transportation equipment can be easily and inexpensively procured at the large-scale production bases of ammonia. As described above, liquefied petroleum gas and its component hydrocarbon species, as well as methanol, can be advantageously procured at the large-scale production bases of ammonia. Therefore, ammonia-mixed fuels containing these can be advantageously used as the driving fuel for transportation equipment for transporting ammonia in large quantities. Moreover, by utilizing the similarity that the saturated vapor pressures and liquefaction temperatures of liquefied petroleum gas and liquefied ammonia are close, it is possible to share the pressure-resistant or cooling tanks for storing them. Therefore, about 20% of the liquefied petroleum gas tankers currently operating in the world are designed to be able to carry liquefied ammonia as well. For this reason, the fact that the loaded liquefied ammonia, liquefied petroleum gas, and its component hydrocarbon species can be used in combination as the fuel for propulsion engines such as engines, gas turbines, and steam turbines used for the propulsion of those tankers not only enables equipment to be aggregated but also has great significance in suppressing GHG emissions from the internal combustion / external combustion engines for propulsion of those tankers.

[0045] (Surfactant, and Emulsification by Surfactant) In an ammonia mixed fuel according to an embodiment, which contains, as a combustion improver, a nonpolar hydrocarbon for the raw material that is poorly miscible with liquefied ammonia, it is preferable to include a surfactant in order to make the liquid ammonia and the combustion improver into an emulsion state. Emulsification by the surfactant can be suitably applied regardless of whether the hydrocarbon for the raw material contained in the ammonia mixed fuel is liquefied petroleum gas, naphtha, gasoline, light oil, or any of these component hydrocarbon species. In particular, when the hydrocarbon for the raw material is any of kerosene, light oil, and these component hydrocarbon species, emulsification by the addition of a surfactant is necessary because it is poorly miscible with ammonia in the temperature range from around normal temperature (25°C) to about 50°C. Due to the emulsification caused by the addition of the surfactant, at least a part of the phase separation portion that could not be miscible in the liquid phase of the ammonia mixed fuel at the gas-liquid-liquid equilibrium at that temperature can be further dispersed in the liquid phase while maintaining that temperature. For example, taking as an example the case of an ammonia mixed fuel using propane, which is a component hydrocarbon species of liquefied petroleum gas, as a combustion improver, in the gas-liquid equilibrium relationship of the ammonia-propane system at 20°C shown in Fig. 1(a), at 20°C, it separates into two phases. Even at the liquid phase composition (ammonia concentration x C ≈77 mass%) near point C in Fig. 1(a), uniform emulsification can be achieved by adding an appropriate amount of a suitable surfactant. For example, by adding about 1 mass% of a mixed system surfactant common to that used in Example 3 described later to emulsify the upper liquid phase mainly composed of propane (ammonia concentration x A = 16.2 mass%, mass ratio to the whole (x B -x C ) / (x B -x A )≈0.14), the other lower liquid phase mainly composed of ammonia (ammonia concentration x B = 86.5 mass%, mass ratio to the whole (x C -x A ) / (x B -x A) can be uniformly dispersed within (≈0.86). This uniform emulsion state is maintained even when cooled to about 17°C (the upper layer separates and appears below 17°C). The above emulsification can be similarly achieved not only for n-butane but also for other component hydrocarbon species of liquefied petroleum gas. Due to the above emulsification, the soluble amount of the combustion improver (liquefied petroleum gas and its component hydrocarbon species) in ammonia at a predetermined temperature increases, so that the above-mentioned combustion improving effect during the combustion of the mixed fuel can be further enhanced, and the temperature required for solubilization can be reduced. Therefore, the increase in the saturated vapor pressure of the ammonia mixed fuel can also be suppressed. Accordingly, the required pressure resistance of the storage container during storage near room temperature (25°C) can be reduced by emulsification by adding a surfactant.

[0046] The addition amount of the surfactant is adjusted according to the molecular weight, compounding composition, characteristics, performance, etc. of the surfactant described later. Basically, among liquefied ammonia and the combustion improver, based on the volume fraction (approximately the mass fraction is also acceptable) of the one that becomes fine droplets and is dispersed and suspended in the liquid phase mainly composed of the other, it is appropriately determined. For example, when liquefied ammonia becomes fine droplets (when the combustion improver is liquefied petroleum gas or its component hydrocarbon species, a part of the combustion improver is dissolved in the liquid phase mainly composed of the liquefied ammonia), and it is dispersed and suspended in the liquid phase mainly composed of the combustion improver (hereinafter, this state is referred to as "a / o (ammonia in oil) emulsion"), the addition amount of the surfactant is determined according to the volume fraction of liquefied ammonia in the ammonia mixed fuel. Conversely, when the combustion improver becomes fine droplets (when the combustion improver is liquefied petroleum gas or its component hydrocarbon species, a part of the liquefied ammonia is dissolved in the liquid phase mainly composed of the combustion improver), and it is dispersed and suspended in the liquid phase mainly composed of ammonia (hereinafter, this state is referred to as "o / a (oil in ammonia) emulsion"), the addition amount of the surfactant is determined according to the volume fraction (approximately the mass fraction) of the combustion improver in the mixed fuel. The emulsion formed by the mixed surfactant used in Example 3 described above corresponds to this o / a emulsion. Generally, the larger the volume fraction (approximately the mass fraction) of liquefied ammonia or the combustion improver that becomes fine droplets and is dispersed and suspended in the mixed fuel, the more surfactant is generally required. The required amount of surfactant varies depending on the type of surfactant. However, when using a suitable surfactant described later (a high-performance one among the mixed surfactants mixing non-ionic and ionic surfactants), as a guideline, a surfactant with a mass fraction of approximately 1 / 10 of the numerical value of the volume fraction (approximately the mass fraction) of liquefied ammonia or the combustion improver that is dispersed and suspended in the mixed fuel is preferable for forming a stable emulsion. Usually, it is added to the ammonia mixed fuel in an amount of about 0.1 to 10% by mass. Also, when using such a mixed surfactant system of nonionic and ionic surfactants together, it is possible to make polar ammonia and nonpolar hydrocarbon for raw materials into either the above a / o emulsion or o / a emulsion state. Furthermore, surfactants particularly suitable for the formation of each can be appropriately selected or adjusted by formulation or the like so as to preferentially form any of these. Generally, when the volume of the separated liquid phase mainly composed of liquefied ammonia is smaller than the volume of the separated liquid phase mainly composed of hydrocarbon for raw materials, forming an a / o emulsion is more advantageous in terms of saving the amount of surfactant and uniformly dispersing it throughout, and for this reason, a surfactant that is more likely to form an a / o emulsion is selected or formulated. In the opposite case, a surfactant that is more likely to form an o / a emulsion is selected or formulated. However, there may be cases where the same surfactant can be adapted to both a / o emulsification and o / a emulsification by selection or formulation.

[0047] In the ammonia-mixed fuel of the above-described embodiment, a preferable surfactant is a mixed surfactant system including at least one nonionic surfactant (A) and at least one ionic surfactant (B). However, the "ionic" and "nonionic" here are to be distinguished by whether or not they have the property of ionizing in the environment in the liquid-state ammonia-mixed fuel. General terms of "ionic" and "nonionic" are mainly distinguished from the viewpoint of whether or not they ionize as hydrated ions in the presence of water. However, since the ammonia-mixed fuel in the present invention substantially does not contain water, "ionic" and "nonionic" are distinguished by whether or not they can ionize as ions mainly solvated by ammonia in the ammonia-mixed fuel. Also, in the process of such ionization, there may be a transfer or exchange of H + or anionic species / cationic species, etc., and the above "ionic" and "nonionic" are distinguished by the presence or absence of ionization including such a series of processes. Generally, a surfactant has the property that surfactant molecules having two parts showing affinity for each of two phases that undergo liquid phase separation are arranged two-dimensionally at the interface between the two phases while opposing the parts having affinity for each of the two phases. In order for such a surfactant to exhibit the effect of emulsification, when one of the separated two liquid phases is divided into a large number of minute droplets by stirring and dispersed in the other phase, the surfactant molecules are arranged two-dimensionally at the surface interface of all the minute droplets in the above manner and continuously cover the minute droplets (formation of so-called “micelles”), and a stable electrostatic repulsive force is generated between the minute droplets (micelles) so as to prevent the minute droplets (micelles) from recontacting and refusing. It is necessary to have both of these two elements.

[0048] In the case of the formation of emulsions between general liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and their component hydrocarbon species and water, there are many surfactants that can form emulsions alone for both nonionic and ionic types. However, when emulsifying an ammonia mixed fuel containing liquefied ammonia and the hydrocarbon for the raw material, the present inventor tried typical commercially available nonionic and ionic surfactants alone, but the effect of emulsion formation was poor in each case and it was separated into two layers as in the case without addition. This is presumably because the polarity of ammonia is not as high as that of water and the polarity difference from the hydrocarbon for the raw material is smaller than in the case of an aqueous system, so that it is difficult for a single surfactant to satisfy both of the above two elements of two-dimensionally arranging at the surface interface of minute droplets and covering the minute droplets (formation of micelles) and giving sufficient electrostatic repulsion between micelles. However, as will be described later, the present inventors have found that by mixing and using several types of nonionic surfactants and several types of ionic surfactants in an appropriate quantitative ratio, an ammonia mixed fuel containing liquefied ammonia and the hydrocarbon for raw materials (liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and their component hydrocarbon species) can be stably and favorably emulsified. Here, the nonionic surfactant mainly contributes to the stable formation of an extremely thin film (the film at the micelle interface) that covers the minute droplets while arranging two-dimensionally on the surface interface of the minute droplets. On the other hand, the ionic surfactant mainly contributes to imparting stable electrostatic repellency to the surface interface of the minute droplets (micelles) by itself being constantly ionized while participating in the formation of the film by the nonionic surfactant, and preventing the re-contact and re-fusion of the minute droplets. Thus, when a suitable nonionic and ionic surfactant are mixed and used, the ammonia mixed fuel can be favorably emulsified by the synergistic effect of the above-described respective contributions. However, even a nonionic surfactant suitable for film formation at the micelle interface or an ionic surfactant suitable for ionization repulsion alone has difficulty in forming a stable emulsion. That is, only the former has insufficient electrostatic repulsion between the formed micelles, and repeatedly contacts and fuses the transiently generated micelles, eventually re-separating into two phases. Also, only the latter has insufficient film-forming property at the two-phase interface, so it is difficult to form micelles themselves. In addition, the category of "mixing of nonionic surfactant (A) and ionic surfactant (B)" in the above-mentioned "suitable surfactant" includes, in addition to the simple physical mixing of each surfactant, a mode in which a molecule of one surfactant has both nonionic and ionic polar sites. Such surfactants also include copolymers in which the above-mentioned two types of ionic and ionic polar sites are polymerized. As its molecular structure, for example, there are those having the partial structure of the above-mentioned suitable nonionic surfactant and the partial structure of the above-mentioned suitable ionic surfactant in series in the main chain, and those having the partial structure of the above-mentioned suitable nonionic surfactant and the partial structure of the above-mentioned suitable ionic surfactant in parallel as side chains. In these, the quantitative ratio between the partial structure part of the nonionic surfactant and the partial structure part of the ionic surfactant is determined according to the respective quantitative ratios that are suitable in the case of a simple physical mixing of the nonionic and ionic surfactants described above.

[0049] Among the above-mentioned suitable mixed surfactant systems, particularly suitable surfactants specifically have the following modes. That is, (A) In the molecular structure, a primary or secondary amino group [-NH2, or >NH], a polyoxyalkylene amino group [>N(C a H 2a O) c -H, or -N((C b H 2b O) d -H)((C b H 2b O) e -H)](a and b are 2 or 3, c is an integer from 1 to 8, d and e are 0 or positive integers such that d + e = 1 to 8), an amide group [-C(=O)NH2], a polyoxyalkylene amide group [-C(=O)N((C f H 2f O) g -H)((C f H 2f O) h -H)](f is 2 or 3, g and h are 0 or positive integers such that g + h = 1 to 8), and a polyoxyalkylene group [-O(Ci H 2i O) j -H](where i is 2 or 3, and j is an integer from 1 to 8), has at least one group as a nonionic polar site, and an alkyl group [C k H 2k+1 -](where k is an integer from 7 to 18), and an alkenyl group [C l H 2l-1 -](where l is an integer from 7 to 18), has at least one group as a nonpolar site, at least one of the said nonionic surfactants, (B) In the molecular structure, a quaternary methylammonium group, a quaternary methylalkanolammonium group, or a quaternary alkanolammonium group [-N + (CH3) p (C m H 2m OH) q ·X - 、or >N + (CH3) r (C n H 2n OH) s ·X’ - (where m and n are 2 or 3, p and q are 0 or positive integers such that p + q = 3, r and s are 0 or positive integers such that r + s = 2, X and X’ are any one of Cl, Br, and I), and a carboxyl group [-C(=O)OH], has at least one group as an ionic polar site, and an alkyl group [C t H 2t+1 -](where t is an integer from 7 to 18), and an alkenyl group [C u H 2u-1 -](where u is an integer from 7 to 18), has at least one group as a nonpolar site, at least one of the said ionic surfactants, is a mixed surfactant containing.

[0050] In the above, (A) is a nonionic surfactant as the main component constituting a particularly suitable surfactant in the ammonia mixed fuel containing the nonpolar hydrocarbon for raw materials as an auxiliary fuel, and (B) is an ionic surfactant as the subcomponent constituting a particularly suitable surfactant. As described above, the nonionic surfactant (A) mainly contributes to the formation of a thin film in which its molecules are two-dimensionally arranged and micelles covered with the film at the interface between the separated two liquid phases, and the ionic surfactant (B) mainly contributes to ionization in the film and bringing about electrostatic repulsion between the micelles. Among the above, the molecule of the nonionic surfactant (A) has, as a nonionic polar site, a primary or secondary amino group [-NH2, or >NH], a polyoxyalkylene amino group [>N(C a H 2a O) c -H, or -N((C b H 2b O) d -H)((C b H 2b O) e -H)](a and b are 2 or 3, c is an integer from 1 to 8, d and e are 0 or positive integers such that d + e = 1 to 8), an amide group [-C(=O)NH2], and a polyoxyalkylene amide group [-C(=O)N((C f H 2f O) g -H)((C f H 2f O) h -H)](f is 2 or 3, g and h are 0 or positive integers such that g + h = 1 to 8), or a polyoxyalkylene group [-O(C i H 2i O) j-H] (where i is 2 or 3 and j is an integer from 1 to 8), it has a high affinity based on hydrogen bonding with respect to liquid ammonia or a liquid phase mainly composed of liquid ammonia. These nonionic surfactants (A), including the case where the polar part is an amino group, hardly ionize themselves in an ammonia mixed fuel without water (thus being classified as "nonionic"). Also, since the nonionic surfactant (A) has a nonpolar long-chain alkyl group [C k H 2k+1 -] or a long-chain alkenyl group [C l H 2l-1 -] (where k and l are integers from 7 to 18), it also has a high affinity for the liquid phase mainly composed of hydrocarbon for raw materials or hydrocarbon for raw materials. Moreover, among commercially available surfactant types, while some may dissolve in either the liquid phase mainly composed of liquid ammonia or the liquid phase mainly composed of hydrocarbon for raw materials, the above nonionic surfactant (A) has the characteristic that, probably due to the balance of its affinity, its solubility in either liquid phase is low, and it is likely to migrate to the interface between the two phases without dissolving in either phase.

[0051] As the nonionic surfactant (A), when forming an emulsion between a liquid phase mainly composed of liquid ammonia or liquid ammonia and a liquid phase mainly composed of hydrocarbon for raw materials or hydrocarbon for raw materials, in the trials of the present inventor, a long-chain alkylamine having a single long-chain alkyl group and a primary amino group (-NH2) [structural formula: C k H 2k+1 NH2] (where k is an integer from 7 to 18) showed the highest effect. Such long-chain alkylamines migrate to the interface between the two phases and form a good film, and as a result, micelles are also likely to form. Such nonionic surfactants (A) of long-chain alkylamines can be used well in either the case of forming the above a / o emulsion or o / a emulsion. In particular, it seems to have a tendency to form the latter more easily, and thus it is particularly effective in emulsifying a mixed fuel containing a large amount of liquid ammonia and a relatively small amount of hydrocarbon for raw materials. Also, when forming an emulsion between liquid ammonia or a liquid phase mainly composed of liquid ammonia and a hydrocarbon for raw materials or a liquid phase mainly composed of a hydrocarbon for raw materials among the nonionic surfactants (A), those showing a film-forming effect at the interface similar to the above long-chain alkylamine are as follows: Long-chain alkyl polyoxyalkylene amine having one long-chain alkyl group and a polyoxyalkylene amino group [structural formula: C k H 2k+1 N((C b H 2b O) d -H)((C b H 2b O) e -H)] (b is 2 or 3, d and e are 0 or positive integers such that d + e = 1 to 8, k is an integer from 7 to 18), Long-chain alkyl amide having one long-chain alkyl group and an amide group [structural formula: C k H 2k+1 -C(=O)NH2] (k is an integer from 7 to 18), Long-chain alkyl polyoxyalkylene amide having one long-chain alkyl group and a polyoxyalkylene amide group [structural formula: C k H 2k+1 -C(=O)N((C f H 2f O) g -H)((C f H 2f O) h -H)] (f is 2 or 3, g and h are 0 or positive integers such that g + h = 1 to 8, k is an integer from 7 to 18), and Polyalkoxyethylene long-chain alkyl ether having one long-chain alkyl group and a polyoxyalkylene group [structural formula: C k H 2k+1 O(C i H 2i O) j -H] (i is 2 or 3, j is an integer from 1 to 8, k is an integer from 7 to 18) can be mentioned. Among them, long-chain alkyl (and long-chain alkenyl) polyoxyalkylene amines, long-chain alkyl (and long-chain alkenyl) polyoxyalkylene amides, and polyalkoxyethylene long-chain alkyl (or long-chain alkenyl) ethers having a partial structure of a polyoxyalkylene group (polyether) may be particularly effective in forming an emulsion when alcohol for raw materials is also included in addition to liquefied ammonia and hydrocarbon for raw materials.

[0052] On the other hand, as the ionic surfactant (B), when forming an emulsion between liquefied ammonia or a liquid phase mainly composed of liquefied ammonia and a liquid phase mainly composed of hydrocarbon for raw materials or hydrocarbon for raw materials, in the trials of the present inventors, a quaternary long-chain alkyltrimethylammonium having a single long-chain alkyl group and a trimethylammonium group [structural formula: C k H 2k+1 N + (CH3)3·X - (k is an integer from 7 to 18) showed the highest effect. The quaternary long-chain alkyltrimethylammonium ionizes at the boundary with the liquid phase mainly composed of liquefied ammonia while participating in the film formation at the interface by the nonionic surfactant (A). Therefore, it can prevent the contact and fusion of micelles well. Such an ionic surfactant (B) of quaternary long-chain alkyltrimethylammonium can be used well in forming either the above-mentioned a / o emulsion or o / a emulsion. Similar to the above long-chain alkylamine in the nonionic surfactant (A), it seems to have a particular tendency to easily form an o / a emulsion. Therefore, it is particularly effective in emulsifying a mixed fuel containing a large amount of liquefied ammonia and a relatively small amount of hydrocarbon for raw materials. In addition, one to three methyl groups [-CH3] of the above trimethylammonium group are replaced with alkanol groups [C m H 2m OH](m is 2 or 3), and a long-chain alkylmethylalkanolammonium having a quaternary ammonium group as a polar part [C k H 2k+1 N + (CH3)p (C m H 2m OH) q ·X - (where k is an integer from 7 to 18, m is 2 or 3, p and q are 0 or positive integers such that p + q = 3, and X is any one of Cl, Br, and I) The ionic surfactant (B) forms an emulsion between liquid ammonia or a liquid phase mainly composed of liquid ammonia and a hydrocarbon for raw materials or a liquid phase mainly composed of a hydrocarbon for raw materials, and exhibits film formation and ionization effects at the interface similar to those having a trimethylammonium group. Further, these ionic surfactants (B) having a quaternary methylalkanolammonium group may be particularly effective in forming an emulsion when including an alcohol for raw materials in addition to liquid ammonia and a hydrocarbon for raw materials in a liquid state.

[0053] Furthermore, those having a carboxyl group [-C(=O)OH] as the polar part of the ionic surfactant (B) can also be preferably used when forming an emulsion with a hydrocarbon for raw materials or a liquid phase mainly composed of a hydrocarbon for raw materials. For example, a long-chain alkylcarboxylic acid having a carboxyl group as the polar part [structural formula: C k H 2k+1 C(=O)OH] (where k is an integer from 7 to 18) of the ionic surfactant (B) also donates H + to coexisting ammonia (and the long-chain alkyl (or long-chain alkenyl) amine in (A)) at the boundary with the liquid phase mainly composed of liquid ammonia while participating in film formation at the interface by the non-ionic surfactant (A) and ionizes [ionization formula: -C(=O)OH + NH3 (or C k H 2k+1 NH2, etc.) = -C(=O)O - +NH4 + (or C k H 2k+1 NH3 +etc.), as a result, the micelles are electrostatically repelled from each other, preventing contact and fusion of the micelles. Further, the ionic surfactant (B) having such a long-chain alkyl group or alkenyl group and a carboxyl group can form either of the above a / o emulsion and o / a emulsion, but particularly tends to form the former. Therefore, it is particularly effective in emulsifying a mixed fuel containing a large amount of hydrocarbon for raw materials and a relatively small amount of liquefied ammonia. Furthermore, a long-chain dialkyl (or long-chain dialkenyl) amine [structural formula: (C k H 2k+1 )2NH2, or (C l H 2l-1 )2NH2] (k and l are integers from 7 to 18) of (A), or a quaternary long-chain dialkyl or dialkenyldimethylammonium [structural formula: (C + (CH3)2·X - ) having two long-chain alkyl groups or alkenyl groups and a dimethylamino group [>N k H 2k+1 )2N + (CH3) r (C n H 2n OH) s ·X’ - , or (C l H 2l-1 )2N + (CH3) r (C n H 2n OH) s ·X’ - (n is 2 or 3, r and s are 0 or positive integers such that r + s = 2, X’ is any of Cl, Br, and I) of (B), when added in small amounts to (A) which is a simple long-chain alkyl (or long-chain alkenyl) amine having one of the above long-chain alkyl groups or alkenyl groups and a primary amino group (-NH2), or (B) which is a quaternary long-chain alkyltrimethylammonium having one of the above long-chain alkyl groups or alkenyl groups and a trimethylammonium group, tends to more easily form the o / a emulsion.

[0054] The mixing ratio of the nonionic surfactant (A) and the ionic surfactant (B) in the above mixed surfactant ((A)+(B)) is preferably in the range of approximately 0.7:0.3 to 0.9:0.1 in terms of molar ratio. In particular, an emulsion is most favorably formed at approximately 0.80:0.20 (see the comparison of Example 3 and Example 11 described later with Reference Example 1 and 2). Further, in the above, the carbon numbers k, l, t, and u of the long-chain alkyl groups or alkenyl groups of the nonionic surfactant (A) and the ionic surfactant (B) are appropriately selected according to the temperature at which the ammonia mixed fuel is prepared and stored. Generally, the higher the temperature, the more suitable it is to have a larger carbon number. For example, when the temperature of preparation and mixing is near the liquefaction temperature of ammonia (-33 °C) under atmospheric pressure (for example, about minus 10 °C), k, l, t, and u are preferably about 7 to 8 in order to suppress solidification precipitation of the surfactant at low temperatures. Also, when near room temperature (25 °C), for example, about 0 to 50 °C, these carbon numbers are often preferably about 10 to 14 in order to achieve both stability and fluidity of the arrangement at the separated liquid phase interface. At higher temperatures, generally, a larger carbon number is suitable. Therefore, the surfactant has a temperature range suitable for expressing its function. On the other hand, the temperature at which the ammonia mixed fuel is prepared and stored is often selected according to the type of the combustion improver. For example, when the combustion improver is liquefied petroleum gas and its component hydrocarbon species, it is preferable that its saturated vapor pressure is as low as possible from the viewpoints of the pressure resistance of the mixing container and ease of operation. Therefore, the temperature of preparation and mixing is carried out from near the liquefaction temperature of ammonia under atmospheric pressure to near room temperature (25 °C), that is, about minus 10 °C to 50 °C. Also, when the combustion improver is naphtha, gasoline, kerosene, and light oil, or their component hydrocarbon species, from the viewpoints of their viscosity and stirring and mixing properties, the temperature of preparation and mixing is often selected to be near room temperature (25 °C), for example, about 0 to 50 °C or a higher temperature range. Also, when using a mixed system surfactant with a plurality of chain lengths (carbon numbers) in which the above chain lengths (carbon numbers k, l, t, and u) are distributed within a certain range, a more stable emulsion may be formed in some cases. For example, the carbon numbers of the long-chain alkyl groups derived from inexpensive coconut oil have a specific distribution (k,t≒8 to 18: generally, among these, the proportion of k,t = 12 is about 60% and is the largest), and mixed system surfactants having these may easily form a stable emulsion. Therefore, a surfactant having a long-chain alkyl group or alkenyl group suitable for the temperature range corresponding to the liquid-phase composition to be emulsified is selected as described above. By maintaining that temperature range, at least a part, and further the whole, of the liquid-phase portion of the ammonia mixed fuel becomes an emulsion state of the ammonia and the combustion aid, and can be burned well.

[0055] In addition, the nonionic and ionic surfactants having the above molecular structures have a high affinity based on hydrogen bonding for polar ammonia molecules (and also for the molecules of the raw material alcohol having 3 or less carbon atoms that can be additionally added), and have polar parts with appropriate polarity whose local structures of the atomic arrangements of the molecules are also similar to each other.

[0056] Furthermore, the nonionic and ionic surfactants used in the above ammonia mixed fuel do not have a molecular structure part that has a problem with durability against the alkalinity exhibited by ammonia and are chemically stable. On the other hand, for example, it is not preferable that ester groups (-C(=O)-O-), urethane groups (-O-C(=O)-NH-), etc. that are easily deteriorated under alkalinity are contained in the molecular structure. In particular, when the combustor that burns the ammonia mixed fuel is a reciprocating engine or the like having a movable part that requires slidability, a surfactant that can generate a by-product that becomes ash in the combustion gas and can deteriorate the slidability during the combustion of the mixed fuel should be avoided. For example, as the above ionic surfactant, a surfactant having a polar part such as sulfonate (polar part is -SO3 - ·Na + etc.) can be used, but in that case, ash containing sodium sulfate or the like generated after combustion is generated as a by-product that is disadvantageous for sliding, so it is not preferable as the surfactant used in the ammonia mixed fuel of the present invention. In Examples 3 to 12 described below, when n-butane, which is a component of liquefied petroleum gas, is used as a combustion improver and a predetermined amount of various mixed surfactants is added and mixed, the lower limit temperature at which the upper and lower two-phase separation state is eliminated and uniformly solubilized by the formation of an emulsion (in this case, an o / a emulsion), and the saturated vapor pressure at that time are listed (the reference for comparison is Example 2 without adding a surfactant). From these examples, it can be seen that by emulsification by adding a mixed surfactant, the temperature required for solubilization can be reduced, and thereby, an increase in the saturated vapor pressure of the ammonia mixed fuel can also be suppressed. Therefore, by emulsification by adding these mixed surfactants, the soluble amount of the combustion improver n-butane in ammonia at a predetermined temperature increases, and the required pressure resistance of the storage container during storage can also be reduced.

[0057] (Apparatus and Method for Producing Ammonia Mixed Fuel) FIG. 2 is a diagram showing an example of the configuration of an apparatus for producing an ammonia mixed fuel according to an embodiment. The production apparatus 10 shown in FIG. 2 is an apparatus for producing an ammonia mixed fuel when the combustion improver is liquefied petroleum gas and the hydrocarbon species that are components of liquefied petroleum gas. Liquefied petroleum gas and the hydrocarbon species contained as its components are preferable in that, compared with conventionally widely used liquid fossil fuels such as gasoline, kerosene, light oil, or heavy oil, less CO2 is generated per calorific value during combustion. Further, liquefied petroleum gas and its component hydrocarbon species have a saturated vapor pressure close to that of ammonia in the liquid state at the same temperature, and are easily ignited because they have a lower ignition temperature than ammonia, and also have a higher combustion rate (about 5 to 6 times that of ammonia in laminar combustion rate), and are easily combusted. Therefore, liquefied petroleum gas and the hydrocarbon species contained as its components are preferable as combustion improvers for ammonia. An ammonia mixed fuel containing such a combustion improver can be produced by the production apparatus 10 shown in FIG. 2. The manufacturing apparatus 10 mainly includes a sealed container 12 for storing ammonia, a sealed container 14 for storing a combustion aid, a sealed container 16 for mixing, an ammonia introduction line 18, a combustion aid introduction line 20, a gas-phase discharge line 21, a liquid-phase discharge line 22, a stirrer 24, a thermometer 33, and a pressure gauge 31. In addition to these, as shown in FIG. 2, the manufacturing apparatus 10 further includes a surfactant storage container 26, a surfactant introduction line 28, a nitrogen gas introduction mechanism 30, flow meters 18a, 20a, 28a, regulating valves 18b, 20b, 28b, 18c, 20c, 28c, and a control device 32. The regulating valves 18c, 20c, 28c are inlet valves for introducing raw materials into the sealed container 16 for mixing. Further, around the sealed container 16 for mixing, a temperature control jacket 17 for adjusting the temperature inside the sealed container 16 for mixing, a temperature control medium inlet nozzle 17a at its lower part, and a temperature control medium outlet nozzle 17b at its upper part are provided.

[0058] The sealed container 12 for storing ammonia is a cylinder or a tank for storing ammonia in a liquid state (liquefied ammonia). The sealed container 14 for storing a combustion aid is a cylinder or a tank for storing a combustion aid in a liquid state that aids the combustion of ammonia. Here, the combustion aid is at least one of (a) liquefied petroleum gas and (b) a hydrocarbon for raw materials, which is at least one hydrocarbon species contained as a component in liquefied petroleum gas, as described above.

[0059] A stirrer 24 is provided in the sealed container 16 for mixing. The sealed container 16 for mixing is configured to obtain a dissolved solution state or an emulsified mixture by stirring and mixing liquid ammonia and a combustion aid with the stirrer 24, and the mixture obtained by stirring and mixing with the stirrer is configured to maintain a gas-liquid equilibrium state. Specifically, the sealed container 16 for mixing has a pressure-resistant structure and airtightness so that the inside of the sealed container 16 for mixing can maintain the saturated vapor pressures of ammonia, the combustion aid, and their mixtures.

[0060] The ammonia introduction line 18 is provided with a flow meter 18a and regulating valves 18b and 18c configured to introduce a predetermined amount into the ammonia storage sealed container 12 and the mixing sealed container 16, serving as an ammonia metering introduction mechanism. The control device 32 receives the measurement result of the ammonia flow rate by the flow meter 18a, generates a control signal for controlling the opening degrees of the regulating valves 18b and 18c, and sends the generated control signal to the regulating valves 18b and 18c. During metering introduction, when the control device 32 determines that the time integral value of the ammonia flow rate from the start of ammonia introduction has reached the set amount to be introduced into the mixing sealed container 16, the regulating valves 18b and 18c are fully closed by the control signal generated by the control device 32, and the introduction is stopped. Note that, for example, a flow meter that obtains the flow rate based on the floating height of a float that floats due to the upward flow of the fluid in the pipe of the ammonia introduction line 18, a critical nozzle type or thermal type flow sensor type mass flow meter or mass flow controller, an ultrasonic type flow velocity meter, or a Coriolis type flow meter, etc. is used for the flow meter 18a. At this time, the introduced amount of ammonia can be obtained by the time integration of the flow rate measurement values from the start to the end of ammonia introduction. Note that instead of the flow meter 18a in FIG. 2, a weighing device (not shown) for weighing the weight of the mixing sealed container 16 is separately provided, and it is also possible to control the introduced amount of ammonia from the weighing value of the weighing device accompanying the introduction of liquefied ammonia into the mixing sealed container 16. However, this control method cannot be applied to the case of continuously producing an ammonia mixed fuel with a constant composition by continuously introducing the raw material ammonia and the combustion improver shown in FIG. 5 described later. In that case, the ammonia metering introduction mechanism is composed of the weighing device and the regulating valves 18b and 18c. During metering introduction, the control device 32 receives the weighing result by the weighing device, generates a control signal for controlling the opening degrees of the regulating valves 18b and 18c, and sends the generated control signal to the regulating valves 18b and 18c. During metering introduction, when the control device 32 determines that the weighing result of the ammonia introduced amount (the value obtained by subtracting the mass of the mixing sealed container 16 before the start of ammonia introduction) has reached the set amount to be introduced into the mixing sealed container 16, the regulating valves 18b and 18c are fully closed by the control signal generated by the control device 32, and the introduction is stopped.

[0061] The combustion-supporting agent introduction line 20 connects the sealed container 14 for storing the combustion-supporting agent and the sealed container 16 for mixing. On the combustion-supporting agent introduction line 20, a flow meter 20a and regulating valves 20b, 20c configured to introduce a predetermined amount of the combustion-supporting agent from the sealed container 14 for storing the combustion-supporting agent to the sealed container 16 for mixing are provided as a combustion-supporting agent metering introduction mechanism. For the flow meter 20a, one having the same mechanism as the flow meter 18a for liquefied ammonia is used. The control device 32 receives the measurement result by the flow meter 20a, generates a control signal for controlling the opening degrees of the regulating valves 20b, 20c, and sends the generated control signal to the regulating valves 20b, 20c. At the time of metering introduction, when the control device 32 determines that the time integral value of the flow rate of the combustion-supporting agent from the start of introduction of the combustion-supporting agent has reached the set amount to be introduced into the sealed container 16 for mixing, the regulating valves 20b, 20c are fully closed by the control signal generated by the control device 32, and the introduction is stopped. Also, similar to the case of introducing liquefied ammonia, it is also possible to grasp and control the introduction amount of the combustion-supporting agent from the weighing value by the weighing device (not shown) that weighs the weight of the sealed container 16 for mixing instead of the flow meter 20a. However, this control method cannot be applied to the case of continuously producing an ammonia mixed fuel with a constant composition by continuously introducing the raw materials ammonia and the combustion-supporting agent shown in FIG. 5 described later. In that case, the combustion-supporting agent metering introduction mechanism is composed of the weighing device and the regulating valves 20b, 20c. At the time of metering introduction, the control device 32 receives the weighing result of the combustion-supporting agent by the weighing device, generates a control signal for controlling the opening degrees of the regulating valves 20b, 20c, and sends the generated control signal to the regulating valves 20b, 20c. At the time of metering introduction, when the control device 32 determines that the weighing result of the introduction amount of the combustion-supporting agent (the value obtained by subtracting the mass of the sealed container 16 for mixing before the start of introduction of the combustion-supporting agent) has reached the set amount to be introduced into the sealed container 16 for mixing, the regulating valves 20b, 20c are fully closed by the control signal generated by the control device 32, and the introduction is stopped. The saturated vapor pressures of ammonia in the liquid state and the saturated vapor pressures of the liquefied petroleum gas or the hydrocarbon which is a component of the liquefied petroleum gas and serves as the above-mentioned combustion improver are both much higher than the atmospheric pressure near normal temperature (25°C). Therefore, if the internal pressure of the mixing sealed container 16 is about the atmospheric pressure and is sufficiently lower than these saturated vapor pressures, as shown in FIG. 2, even if no liquid transfer pump is provided in the ammonia introduction line 18 and the combustion improver introduction line 20, the saturated vapor pressures inside the ammonia storage sealed container 12 and the combustion improver storage sealed container 14 can cause the liquid phase to be discharged and introduced into the mixing sealed container 16 respectively.

[0062] The nitrogen gas introduction mechanism 30 is provided to replace the gas existing in each introduction line and the mixing sealed container 16 with nitrogen gas as necessary from the perspective of explosion prevention when the manufacturing apparatus 10 is started up and after the production of the ammonia mixed fuel is completed, etc. The nitrogen gas introduction mechanism 30 is provided with a nitrogen gas introduction valve 30a for introducing a predetermined amount of nitrogen gas into the ammonia introduction line 18 and the combustion improver introduction line 20. The opening degree of the nitrogen gas introduction valve 30a is controlled by a control signal generated based on the control signals by which the control device 32 controls the opening degrees of the regulating valves 18b, 18c, 20b, 20c. The introduction of liquefied ammonia and a combustion improver, which is a component hydrocarbon species of liquefied petroleum gas or liquefied petroleum gas, into the above-described mixing sealed container 16 is preferably performed according to the following procedure. When introducing these liquefied gases, ammonia and the combustion improver, they can be introduced into the mixing sealed container 16 by discharging them according to their respective saturated vapor pressures in their respective storage sealed containers (12, 14). At this time, in order to complete both introductions, during these introductions, the saturated vapor pressure of the mixture of both in the mixing sealed container 16 must always be lower than the internal pressure of the ammonia storage sealed container 12 (ammonia saturated vapor pressure) and the internal pressure of the combustion improver storage sealed container 14 (combustion improver saturated high pressure). For this reason, before a series of introduction processes, by temperature control described later, the temperature of the liquid phase of the mixture in the mixing sealed container 16 is maintained at a predetermined temperature such that its saturated vapor pressure becomes sufficiently low (for example, about 0.05 to 0.1 MPa or less) (in many cases, it is substantially cooling to a temperature lower than the external environment). Thereafter, the gas-phase discharge valve 21a is opened (to an open-to-atmosphere state), and a predetermined amount of nitrogen gas is passed through each introduction line into the mixing sealed container 16 by the nitrogen gas introduction mechanism 30. From the perspective of explosion protection, if necessary, the air in each introduction line and the mixing sealed container 16 is temporarily replaced with nitrogen gas. Next, predetermined amounts of liquefied ammonia, combustion improver, and surfactant are sequentially introduced into the mixing sealed container 16 through their respective introduction lines by the aforementioned metering introduction mechanism. During these introductions, in order to avoid a situation where liquefied ammonia, combustion improver, etc. can no longer be introduced due to an increase in the internal pressure of the mixing sealed container 16, as will be described later, the order of introduction is basically preferably from the one with the lower saturated vapor pressure at the temperature during stirring and mixing in the mixing sealed container 16 mentioned above. Among the liquefied gas raw materials of liquefied ammonia, which is a liquefied gas, liquefied petroleum gas as a combustion improver, and its component hydrocarbon species, they are introduced into the mixing sealed container 16 in order from the one with the lower saturated vapor pressure at the set temperature. Here, for example, between ammonia and propane, which is a component of liquefied petroleum gas, at about 15°C or lower, the saturated vapor pressure of propane is higher than that of ammonia, and it reverses at higher temperatures. Attention should be paid to such situations, and the introduction order needs to be selected. At that time, first, it is preferable that the nitrogen gas filling the mixing sealed container 16 is sufficiently excluded and replaced by the vaporized gas of the liquefied gas component with the lowest saturated vapor pressure, which is the first to be introduced among the liquefied gas raw materials. After this gas replacement, the gas-phase discharge valve 21a is closed, and at the same time, the adjustment valves 18b, 18c or the adjustment valves 20b, 20c are opened, and the measurement of the introduction amount (time integral value of the flow rate) of the liquefied gas raw material introduced first is started. After the completion of the introduction of a predetermined amount, the adjustment valves 18b, 18c or the adjustment valves 20b, 20c are closed. When introducing the second and subsequent liquefied gas raw materials, the aforementioned gas replacement is not performed, and the predetermined amounts of the remaining liquefied gas raw materials are introduced in the same manner in ascending order of saturated vapor pressure.

[0063] According to the above configuration and procedure, even if there are no liquid transfer pumps provided in the ammonia introduction line 18 and the combustion aid introduction line 20, due to the discharge caused by the saturated vapor pressures of the liquefied ammonia in the respective storage sealed containers 12 and 14, and the combustion aid which is liquefied petroleum gas or a hydrocarbon species as a component of liquefied petroleum gas, ammonia and the combustion aid can be introduced into the mixing sealed container 16 with a lower internal pressure. However, in the mixing sealed container 16 where ammonia and the above combustion aid have already been introduced, it may be advantageous to be able to introduce the raw material ammonia and the above combustion aid under pressure against the saturated vapor pressure of the mixture of ammonia and the combustion aid (in many cases, the saturated vapor pressure of the mixture is higher than the saturated vapor pressures of ammonia and the above combustion aid alone). In particular, as will be described later, when continuously and quantitatively introducing ammonia and the above combustion aid into the mixing sealed container 16 to continuously produce ammonia-mixed fuel, etc., it is necessary to provide liquid transfer pumps in the ammonia introduction line 18 and / or the combustion aid introduction line 20 respectively. As the liquid transfer pump in that case, it has a lift sufficiently higher than the saturated vapor pressure of the mixture of ammonia and the above combustion aid in the mixing sealed container 16, and a sufficient discharge volume corresponding to the production rate and discharge rate of the ammonia-mixed fuel, and it is required that the discharge volume be variable. In addition to a high-lift centrifugal pump, a positive displacement type such as a gear type, a screw type, a plunger type, or a single-axis eccentric screw type is appropriately selected. When such a high-lift liquid transfer pump is provided in the ammonia introduction line 18 and the combustion aid introduction line 20, it is also possible to forcibly introduce ammonia or the combustion aid into the mixing sealed container 16 regardless of the above-described introduction order. When the liquid feed pump is provided in the ammonia introduction line and / or the combustion aid introduction line, each liquid feed pump is also driven or stopped in conjunction with the regulating valves 18b, 18c and / or the regulating valves 20b, 20c. At this time, when the liquid feed pump is a non-positive displacement centrifugal pump or the like, the liquid feed rate is controlled by adjusting the opening degree of each of the above-mentioned regulating valves. On the other hand, when a positive displacement liquid feed pump such as the vane type, gear type, screw type, plunger type, single-axis eccentric screw type, etc. described above is used, the opening degree of each of the above-mentioned regulating valves is almost fully open during liquid feeding, and the rotation speed of the motor of the liquid feed pump itself is controlled so as to be controlled to a predetermined discharge amount. After the above series of introductions are completed, the regulating valves 18b, 18c, 20b, 20c are all closed, and the mixing sealed container 16 is sealed. The liquid phase temperature of the above mixture in the mixing sealed container 16 is switched from the predetermined temperature at the time of introduction for lowering the saturated vapor pressure to a temperature range preferable in the production of the ammonia mixed fuel described later by the temperature adjustment mechanism described later, and it is preferable that the temperature is maintained during the production of the ammonia mixed fuel thereafter. The above series of controls are performed based on the control signals generated by the control device 32.

[0064] The liquid phase discharge line 22 is usually provided at the lower part, preferably at the bottom of the mixing sealed container 16, and is configured to be able to discharge almost the entire amount of the mixture obtained by the stirring and mixing of the stirrer 24 from the mixing sealed container 16 as an ammonia mixed fuel. However, when the combustion aid is liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, or these component hydrocarbon species, a situation may occur in which the liquid phase of the mixture with ammonia in the mixing sealed container 16 separates into upper and lower two layers. At this time, for the lower liquid phase portion separated by the specific gravity difference, as shown in FIG. 2 described above, it is discharged from the liquid phase discharge line 22 provided at the bottom of the mixing sealed container 16. On the other hand, as a modification of the manufacturing apparatus 10 in FIG. 2, as shown in FIG. 3(a), by extending the liquid-phase discharge line 222 upward from the bottom of the mixing sealed container so that the opening at the upper end of the pipe comes slightly above the upper and lower layer interface, the liquid-phase portion of the upper layer can also be separately discharged. That is, the liquid-phase discharge line of the manufacturing apparatus 10 includes both the form of 22 in FIG. 2 and 222 in FIG. 3. Furthermore, as shown in FIG. 3(b), those having both 221 and 222 are also included. Adjusting valves 22a, 22a1, and 22a2 are provided in these liquid-phase discharge lines 22, 221, and 222, and the opening degrees of the adjusting valves 22a, 22a1, and 22a2 are controlled by control signals from the control device 32. In FIGS. 3(a) and 3(b), only the portions related to the above configuration inside the manufacturing apparatus 10 are shown, and the other portions are omitted.

[0065] As the stirrer 24 provided in the mixing sealed container 16, when the liquid ammonia and the combustion aid are compatible only by simple mixing without adding a surfactant, a general single-type stirring blade type is sufficient. However, when a surfactant is added to form an emulsion, although the above single-type stirring blade type may be applicable in some cases, a single-type or compound planetary (planetary rotation) type stirring blade type, an ultrasonic irradiation type, a type in which the liquid mixture to be stirred is forced to flow under pressure and circulated in a narrow part, etc., which have a higher dispersion effect, can be used more effectively. When a stirrer with a high stirring effect is used, it is easier to form an emulsion state, but an increase in internal pressure may occur due to heat generation associated with the viscous friction of the liquid mixture to be stirred. This inconvenience can be eliminated by adjusting the temperature inside the mixing sealed container 16 by a series of temperature adjustment mechanisms in the embodiments described later.

[0066] In the manufacturing apparatus 10 of one embodiment, a temperature adjustment mechanism is provided that is configured to adjust the temperature of the mixture of ammonia and the combustion aid inside the mixing sealed container 16 to a predetermined temperature. Three functions described below can be realized by this temperature adjustment mechanism. As the first function of the temperature control mechanism, when liquid ammonia and a combustion improver which is liquefied petroleum gas and its component hydrocarbon species are introduced into the mixing sealed container 16 and stirred and mixed by the stirrer 24, the internal pressure of the mixing sealed container 16 (if the nitrogen in the gas phase has been sufficiently replaced in advance by the vaporized gas components of ammonia or the combustion improver which are raw materials, the internal pressure will be equal to the saturated vapor pressure of the mixture) is within a temperature range such that it does not exceed the set pressure resistance of the mixing sealed container 16, and the liquid phase temperature of the mixture is controlled. That is, the liquid phase temperature of the mixture is controlled so that the saturated vapor pressure of the mixture in the mixing sealed container 16 does not exceed the set pressure resistance of the mixing sealed container 16. Thereby, the saturated vapor pressure of the mixture at the assumed maximum mixing temperature can be set as the design pressure resistance of the mixing sealed container 16 (generally, a pressure value with a further safety margin is adopted), and it is no longer necessary to increase the pressure resistance of the mixing sealed container 16 unnecessarily, so that the mixing sealed container 16 and the manufacturing apparatus 10 can be made lighter and less costly. Incidentally, if the liquid phase composition of the mixture in the mixing sealed container 16 is determined, there is a uniform relationship based on vapor-liquid equilibrium between the saturated vapor pressure and the temperature of the mixture (the relationship between the saturated vapor pressure and the temperature is generally accurately represented by an approximate formula such as the Antoine equation). The above pressure resistance design can also be applied when using naphtha, gasoline, kerosene, light oil, and their component hydrocarbon species, or raw material alcohol, which will be described later, as combustion improvers in addition to the above liquefied petroleum gas or its component hydrocarbon species, and further, when using a combination of a plurality of these as combustion improvers, and the mixing sealed container 16 and the manufacturing apparatus 10 can be similarly made lighter and less costly. In addition to the stirrer 24, the temperature control mechanism includes a thermostat that includes a thermometer 33, a pressure gauge 31, a temperature control jacket 17, a heating and cooling mechanism for the temperature control medium m, and a circulation pump for the temperature control medium m. The thermostat is installed outside the manufacturing apparatus 10 and is not shown in FIG. 2. As the temperature control medium m, an inert liquid that is difficult to solidify or volatilize in the temperature control range, such as water, ethylene glycol, diethylene glycol, etc. is selected. In FIG. 2, the temperature control jacket 17 is a heat exchanger that covers the outer periphery of the mixing sealed container 16. The temperature control medium m of the liquid adjusted to a predetermined temperature flows through the inside of the jacket 17, and the outer periphery of the mixing sealed container 16 is heated or cooled, so that the temperature of the mixture of ammonia and the combustion aid inside the mixing sealed container 16 is adjusted to the target temperature by heat exchange. The temperature control medium m is adjusted to a predetermined temperature in the thermostat and then flows into a temperature control medium inlet nozzle 17a provided at the lower part of the jacket 17 via a pipe (not shown). After heat exchange, it is discharged from a temperature control medium outlet nozzle 17b provided at the upper part of the jacket 17 and returns to the thermostat via a pipe (not shown). When adjusting the temperature of the mixture inside the mixing sealed container 16, first, based on the control signal of the stirrer 24 generated by the control device 32, the stirrer 24 is driven at a predetermined output, and the mixture inside the mixing sealed container 16 is stirred. At the same time, based on the control signal generated by the control device 32, the temperature control of the thermostat is activated, and the temperature control medium m adjusted in temperature in the thermostat flows into the jacket 17 and is circulated through the thermostat. During the temperature adjustment of the mixture, the stirring and the circulation of the temperature control medium m are continued, and the liquid phase temperature near the gas-liquid interface inside the mixing sealed container 16 is measured over time by the thermometer 33, and the internal pressure of the gas phase inside the temperature control jacket 17 is measured over time by the pressure gauge 31. The control device 32 receives the measurement results from the thermometer 33 and the pressure gauge 31 over time.

[0067] As the second function of the temperature control mechanism, when ammonia and the combustion aid are introduced into the mixing sealed container 16, the internal pressure of the gas phase and the liquid phase temperature of the mixture in the mixing sealed container 16 are controlled as follows so that these introductions proceed smoothly. For example, in the series of introduction processes of the liquefied gas raw material into the mixing sealed container 16, as described above, the internal pressure of the gas phase (saturated vapor pressure) of the mixture of the liquefied gas raw material already introduced into the mixing sealed container 16 is always lower than the lowest pressure value among the saturated vapor pressures in the respective storage sealed containers of the individual raw materials, liquefied ammonia, liquefied petroleum gas, and its component hydrocarbon species to be introduced hereafter. Therefore, the liquid phase temperature is adjusted to be below the required temperature. Further, in the manufacturing process of the ammonia mixed fuel by stirring and mixing after the introduction of the raw materials into the mixing sealed container 16 is completed, it is preferable that the liquid phase of the mixture of the raw materials in the mixing sealed container 16 be maintained in a preferable temperature range described later. In these temperature controls, the difference between the control target value of the internal pressure of the gas phase in the mixing sealed container 16 and the actual internal pressure measurement value by the pressure gauge 31, or the difference between the control target temperature value of the mixture and the actual temperature value by the thermometer 33 is within the respectively determined allowable ranges (for example, within ±0.01 MPa for the former, within ±1 °C for the latter, etc.). The temperature of the temperature control medium m flowing into the temperature control jacket 17 is adjusted by the output control of the heating / cooling power of the constant temperature bath based on the control signal generated by the control device 32. In order to improve the response speed and accuracy of the temperature control mechanism, the relationship between the vapor-phase internal pressure or liquid-phase temperature of the mixture inside the sealed mixing container 16 after temperature adjustment and the temperature of the temperature control medium m in the constant temperature bath is recognized in advance by the control device 32. Based on these relationships, the output of the heating and cooling power of the constant temperature bath is preferably controlled by using PID control or the like for the temperature of the temperature control medium m in the constant temperature bath according to the control signal generated by the control device 32. Further, in the process of these controls, if the control device 32 determines that there is a risk that the measured value of the vapor-phase internal pressure of the sealed mixing container 16 by the pressure gauge 31 reaches the design pressure resistance of the sealed mixing container 16 due to some unexpected situation, based on the control signal generated by the control device 32, the temperature control medium m in the constant temperature bath is appropriately quenched, or the circulation of the temperature control medium m by the constant temperature bath is stopped (in this case, the latter is effective when the temperature of the temperature control medium m is higher than the temperature of the surrounding environment), thereby avoiding further increase in the internal pressure. In addition, in the above, on the premise of ensuring safety such as explosion protection, instead of adjusting the temperature inside the sealed mixing container 16 by heat exchange with the temperature control medium m in the temperature control jacket 17, for example, a Peltier element, or a combination of a Peltier element and an electric heater, etc. may be provided on the outer periphery of the sealed mixing container 16 (not shown in FIG. 2), and temperature adjustment may be performed thereby. In this case, the temperature adjustment inside the sealed mixing container 16 is performed by controlling the output of heating or cooling by the above Peltier element or the like based on the control signal generated by the control device 32 that has received the internal temperature value measured by the thermometer 33.

[0068] As the third function of the temperature adjustment mechanism, in the manufacturing apparatus 10 of another preferred embodiment, after ammonia and the combustion aid are introduced into the mixing sealed container 16, when they are stirred and mixed by the stirrer 24, the temperature of the mixture is adjusted by the aforementioned temperature adjustment mechanism so that the entire liquid phase portion of the mixture of ammonia and the combustion aid in the mixing sealed container 16 maintaining the gas-liquid equilibrium state is within a temperature range such that it becomes a solution state in which ammonia and the combustion aid are dissolved in each other or an emulsion state of ammonia and the combustion aid. Thereby, the entire mixture becomes an ammonia mixed fuel in which the combustion aid is stably and uniformly dispersed. If this is burned as it is, as described above, uniform vaporization occurs as a whole, and subsequent uniform and high-speed combustion becomes possible. The stabilization and homogenization of the ammonia mixed fuel by the solution formation or emulsification of the entire liquid phase portion by the above temperature adjustment is applicable not only to the above liquefied petroleum gas and its component hydrocarbon species as the combustion aid, but also to naphtha, gasoline, kerosene, light oil, and their component hydrocarbon species described later, and raw material alcohol when using them, and further when using a combination of a plurality of these as the combustion aid, and similarly, its combustibility can be improved. In the above, as the "temperature range such that it becomes a solution state in which ammonia and the combustion aid are dissolved in each other or an emulsion state of ammonia and the combustion aid", an appropriate temperature range is appropriately selected according to the type of the combustion aid and the liquid phase composition of the mixture, and is adjusted to be within that temperature range by the temperature adjustment mechanism. For the case where the combustion aid is liquefied petroleum gas or its component hydrocarbon species, taking the ammonia - propane system at 20°C, which shows the phase equilibrium relationship of the azeotropic liquid phase two-phase separation in Fig. 1(a), as an example, the above temperature range will be described below.

[0069] For example, as described above, the ammonia mixed fuel in the mixing sealed container 16 becomes a gas-liquid equilibrium system having a composition range in which the liquid phase separates into two phases in a relatively low temperature range below the critical miscibility temperature (about 33 ° C in the case of an ammonia - propane mixed system). As described above, each of the two phases after phase separation is in a single "solution state in which ammonia and the combustion aid are dissolved in each other". If at least one of these two phases can be taken out externally, it becomes an ammonia mixed fuel in which the combustion aid is stably and uniformly dispersed. Since both of these two phases can be taken out externally by the configuration described later, within the temperature range corresponding to the liquid phase composition in such a two-phase separation state, it is within the above "temperature range in which ammonia and the combustion aid are in a solution state in which they are dissolved in each other, or an emulsion state of ammonia and the combustion aid". Also, as described above, in a mixture of ammonia and liquefied petroleum gas or its component hydrocarbon species, there exists a temperature at which the entire liquid phase becomes a single-phase solution when the temperature is above a certain predetermined temperature. For example, as shown in FIG. 1(a) above, in the ammonia - propane mixed system, at both compositions of point A and point B (ammonia concentration x A = 16.2 mass%, and x B = 86.5 mass%), since the whole becomes a uniform solution by being maintained at 20 ° C or higher, if this is taken out externally as a single phase, the temperature above this becomes the above "temperature range in which ammonia and the combustion aid are in a solution state in which they are dissolved in each other, or an emulsion state of ammonia and the combustion aid". Furthermore, in the temperature range above the above-mentioned critical miscibility temperature (about 33 ° C in the case of the ammonia - propane mixed system), the composition range in which phase separation occurs disappears, and the mixture becomes a uniform solution at any liquid phase composition and can be taken out externally. Therefore, the temperature range above the critical miscibility temperature becomes the "temperature range in which ammonia and the combustion aid are in a solution state in which they are dissolved in each other, or an emulsion state of ammonia and the combustion aid" regardless of the composition. Furthermore, for example, in the composition of point C in the ammonia - propane mixed system shown in FIG. 1(a) (ammonia concentration x CAt an ammonia concentration of 77% by mass, as described above, when about 1% by mass of a suitable mixed surfactant (the same as that used in Example 3) is added and stirred and mixed, if the temperature is maintained at about 17°C or higher, the phase-separated portion is emulsified and disappears, and the whole can be made into a uniform state. When no surfactant is added, a uniform solution is formed at 23°C. The specifications and operation methods of the production apparatus 10 when using a surfactant will be described later. Therefore, at the composition at point C in the figure (ammonia concentration 77% by mass), when the predetermined amount (about 1% by mass) of the above-mentioned suitable mixed surfactant is added, a temperature of about 17°C or higher falls within the above-mentioned "temperature range in which ammonia and the combustion aid are in a mutually dissolved solution state or an emulsion state of ammonia and the combustion aid". At this time, as the mixed surfactant, it is preferable to select one that exhibits the best performance within this temperature range. In other words, if such a surfactant is selected, the above temperature range also matches the temperature range in which the emulsification performance of the surfactant can be fully utilized. The uniform ammonia mixed fuel produced in the "temperature range in which ammonia and the combustion aid are in a mutually dissolved solution state or an emulsion state according to the composition" as described above, when taken out in that state and used for combustion, exhibits high combustibility.

[0070] Next, in the mixing sealed container 16 of FIG. 2, while the liquid phase temperature is constantly adjusted by the temperature adjustment mechanism, the situation of the composition variation of the ammonia mixed fuel of the ammonia - liquefied petroleum gas (or the hydrocarbon species of the liquefied petroleum gas components) system discharged from the liquid phase discharge line 22 with respect to the liquid phase temperature will be described below, taking the case of the ammonia - propane gas - liquid - liquid equilibrium at 20°C in FIG. 1(a) as an example. When other hydrocarbon species of liquefied petroleum gas components, which form an azeotropic system with a two-phase separation in the liquid phase in the same way as the mixture with ammonia, are used as the combustion aid, although there are differences in the temperature range, pressure range, and composition range, the situation is qualitatively the same.

[0071] (i) Case of the liquid phase composition where the liquid phase is a single phase In the gas-liquid-liquid equilibrium diagram at 20°C in Fig. 1(a) above, in the region where the liquid phase becomes a single-phase solution, the liquid-phase ammonia concentration is 0 mass% to x A in the region between point P and point A mainly composed of propane, and the liquid-phase ammonia concentration is x B to 100 mass%, there are two cases in the region between point B and point Q mainly composed of ammonia. With the corresponding charging composition ratios, liquefied ammonia and liquefied propane are introduced into the mixing sealed container 16 and stirred and mixed, so that a single-phase ammonia mixed fuel having the liquid-phase compositions of the above two regions is prepared. This can be discharged from the liquid-phase discharge line 22 by discharging based on the saturated vapor pressure in the mixing sealed container 16. However, it should be noted that as the above discharge progresses, the composition of the above single-phase ammonia mixed fuel changes as follows with the progress of the discharge. Hereinafter, for the sake of simplicity, it is assumed that sufficient stirring and mixing of the liquid phase is continued even during discharge, the composition and temperature of the entire liquid phase are always uniform, and the liquid-phase temperature does not change. In reality, due to the endothermic heat absorption accompanying evaporation described later, the liquid-phase temperature decreases somewhat with the discharge of the liquid phase, but this is compensated by the temperature adjustment mechanism described above.

[0072] For example, when discharging an ammonia mixed fuel mainly composed of propane, in which the liquid-phase ammonia concentration at the start of discharge corresponds to point A in Fig. 1(a) and is the saturated concentration of x A , as the discharge progresses, the gas-liquid interface drops, increasing the volume of the gas phase and reducing the pressure inside the mixing sealed container 16. In response to this change, inside the mixing sealed container 16, the increase in the gas-phase volume and the evaporation (boiling) of the ammonia-propane mixture from the liquid phase to the gas phase side dynamically maintain the gas-liquid equilibrium. The composition of the evaporated gas in equilibrium with the liquid-phase composition x A at the start of discharge is azeotropic composition y A with a higher ammonia concentration than x O . Therefore, relatively more ammonia evaporates from the liquid phase, so the ammonia concentration in the liquid phase decreases somewhat from x A . As the discharge of the ammonia mixed fuel further progresses, the state of the liquid phase in the mixing sealed container 16 is the point A in Fig. 1(a) at the start of discharge (ammonia concentration xA ) From point (a) in Figure 1, it changes so as to move along the liquidus line AP toward the P point of pure propane (ammonia concentration 0 mass%), and accordingly, the state of the gas evaporated to the gas phase is point O (ammonia concentration y in Figure 1(a)) O ) From point (a) in Figure 1, it changes so as to move along the gas phase line OP toward the P point of pure propane. In this process, the internal pressure in the mixing sealed container 16 decreases from the azeotropic vapor pressure at point O toward the saturated vapor pressure of pure propane at point P as the liquid phase is discharged. In addition, when discharging an ammonia mixed fuel with a liquid phase ammonia concentration in the range of 0 mass% to x A , it is equivalent to starting the above operation from an intermediate point on each of the above-mentioned liquidus line AP and gas phase line OP. On the other hand, when discharging an ammonia-based ammonia mixed fuel with a liquid phase propane concentration at the start of discharge corresponding to point B in Figure 1(a) being 1 - x of the saturated concentration B , the following state changes are shown. That is, as the discharge of the ammonia mixed fuel progresses, the state of the liquid phase in the mixing sealed container 16 (i.e., the ammonia mixed fuel discharged from the liquid phase discharge line 22) changes from point B (ammonia concentration x in Figure 1(a) at the start of discharge) B ) toward the Q point of pure ammonia (ammonia concentration 100 mass%) along the liquidus line AQ, and accordingly, the state of the gas evaporated to the gas phase changes from point O (ammonia concentration y in Figure 1(a)) O ) toward the Q point of pure ammonia along the gas phase line OQ. In this process, the internal pressure in the mixing sealed container 16 decreases from the azeotropic vapor pressure at point O toward the saturated vapor pressure of pure ammonia at point Q as the liquid phase is discharged. In addition, when discharging an ammonia mixed fuel with a liquid phase ammonia concentration in the range of x B to 100 mass%, it is equivalent to the above behavior starting from an intermediate point on each of the above-mentioned liquidus line BQ and gas phase line OQ. Therefore, in the composition region where the liquid phase becomes a single-phase solution, it is necessary to allow the above-described composition changes accompanying the progress of the discharge of the ammonia mixed fuel. However, as described above, when the stirring of the liquid phase is stopped during the discharge and the mass transfer of each component in the liquid phase and at the gas-liquid interface is suppressed, the change in the liquid phase composition near the liquid phase discharge line 22 in the closed container 16 for mixing can be reduced. Further, when the opening degree of the liquid phase discharge valve 22a is increased and the discharge rate of the ammonia mixed fuel is increased, more portions of the ammonia mixed fuel in the closed container 16 for mixing can be discharged while suppressing the above-described composition changes. If the composition change during the discharge may cause any trouble when used as a fuel, the liquid phase discharge valve 22a is closed at that time and the discharge is terminated.

[0073] (ii) In the case of a liquid phase composition in which the liquid phase separates into two phases In the gas-liquid-liquid equilibrium diagram at 20°C in Fig. 1(a), the region where the liquid phase separates into two phases is the region between point A and point B of the ammonia concentration x A ~x B of the liquid phase. By introducing liquefied ammonia and liquefied propane into the closed container 16 for mixing at the charge composition ratio corresponding to the liquid phase composition (ammonia concentration x C ) at an arbitrary position C in this region (the average state of the two liquid phases) and stirring and mixing them, a liquid phase mainly composed of propane with an ammonia concentration of the saturated concentration x A and a liquid phase mainly composed of ammonia with a propane concentration of the saturated concentration 1 - x B (at this time, the ammonia concentration is x B ) are formed in a state of being separated into two phases. At this time, since the specific gravity of liquefied propane is smaller than that of liquefied ammonia, the propane-based phase with an ammonia concentration of x A is on the upper layer, and the ammonia-based phase with an ammonia concentration of x B is on the lower layer. Generally, other constituent hydrocarbon species of liquefied petroleum gas and liquefied petroleum gas mixtures thereof all have a specific gravity smaller than that of liquefied ammonia, so the phases mainly composed of these are always on the upper layer. At this time, as long as the two-phase separation state continues, a constant ammonia concentration x BThe ammonia-based lower layer having [content] can be discharged from the liquid-phase discharge line 22 by discharge based on the saturated vapor pressure in the mixing sealed container 16 as an ammonia mixed fuel. In the above, the above-mentioned constant ammonia concentration x B In order to discharge as much as possible the ammonia-based lower layer having [content], the liquefied ammonia and liquefied propane are preferably introduced into the mixing sealed container 16 with a charging composition ratio such that the position of the above-mentioned point C (average state of the two liquid phases) is closer to point B than near the center of the line segment AB. This is because when point C is close to point A, according to the above-mentioned lever principle, the absolute amount of the lower layer with the ammonia concentration x B decreases, and the timing of shifting to the discharge of the upper layer with the ammonia concentration x A is advanced when the discharge of the lower layer ends. Also, when point C is too close to point B, due to the change (increase) in the average concentration of the liquid phase accompanying the evaporation during the liquid-phase discharge described in (i) above (when point C is close to point B, propane evaporates relatively more than ammonia), the upper layer disappears early, and it shifts to the single-phase state described in (i) above, and the ammonia concentration rises from x B for this reason.

[0074] In the above, in the mixing sealed container 16 of FIG. 2, as described above, the piping of the liquid-phase discharge line 22 is extended upward from the bottom surface of the mixing sealed container 16, and the position of the discharge port at the upper end of the piping is slightly higher than the bottom surface of the upper layer at the start of discharge (222 in FIG. 3(a)). With such a configuration, it is also possible to discharge only the propane-based upper layer with the ammonia concentration x B while leaving the lower layer with the ammonia concentration x A as an ammonia mixed fuel. In this case, in order to discharge as much as possible the upper layer, the liquefied ammonia and liquefied propane are preferably introduced into the mixing sealed container 16 with a charging composition ratio such that the position of the above-mentioned point C (average state of the two liquid phases) is closer to point A than near the center of the line segment AB. Furthermore, as described above, if the outlet in the mixing sealed container 16 has two forms, namely the liquid-phase discharge line 22 at the bottom of the mixing sealed container 16 as shown in FIG. 2 and the liquid-phase discharge line 221 where the position of the outlet is slightly higher than the bottom of the upper layer at the start of discharge as shown in FIG. 3(a) (FIG. 3(b)), the lower layer with ammonia concentration x B and the upper layer with ammonia concentration x A can be simultaneously discharged as ammonia mixed fuel. In this case, it is preferable that liquefied ammonia and liquefied propane are introduced into the mixing sealed container 16 with a charging composition ratio such that the position of the above-mentioned point C (the average state of the entire two liquid phases) is near the center of the line segment AB. However, in the above, with the progress of the discharge of the upper layer with the above ammonia concentration x A and / or the lower layer with ammonia concentration x B , the gas-liquid interface and / or the interface between the upper layer and the lower layer descends, and eventually, the height positions of the in-container outlets of the upper layer and / or the lower layer in the mixing sealed container 16 of the liquid-phase discharge lines 22, 221, 222 reach the descending gas-liquid interface and / or the interface between the upper layer and the lower layer, and further discharge of the above upper layer and / or lower layer cannot be continued. Therefore, if it is desired to avoid the mixing of heterogeneous phases (layers or gas phases of the liquid phase not targeted) in the discharged material, the liquid-phase discharge valves 22a, 22a1, 22a2 are closed by that time.

[0075] In the above, when liquefied ammonia and liquefied propane are introduced into the mixing sealed container 16 with a charging composition ratio corresponding to the liquid-phase composition (ammonia concentration x C ) in the two-phase separation region, the ammonia concentration x A in the above upper layer (x A corresponds to the saturation concentration of ammonia in the upper layer), and the ammonia concentration x B in the above lower layer (1 - x B corresponds to the saturation concentration of propane in the above lower layer) can be controlled as follows by maintaining the temperature of the liquid phase in the mixing sealed container 16 at a predetermined temperature while stirring and mixing it with the temperature adjustment mechanism. For example, the ammonia concentrations x A ’ and x B ’ at both ends of the two-phase separation region at 0 °C shown in Fig. 1(a) above are approximately 6.7% by mass and approximately 93.5% by mass, respectively. At 20 °C, the liquid-phase composition range of the two-phase separation region is reduced compared to that at 0 °C, and x A is approximately 16.2% by mass, and x B is approximately 86.5% by mass. As described above, by maintaining the liquid-phase temperature in the sealed mixing container 16 at 0 °C to 20 °C by the temperature adjustment mechanism, the upper layer and / or the lower layer having the above compositions (x A , x B ) can be discharged. When the holding temperature of the liquid phase during stirring and mixing is further reduced below 0 °C, x A and x B approach 0% by mass and 100% by mass, respectively. Also, when the liquid-phase temperature is further increased beyond 20 °C, the two-phase separation region gradually shrinks, and x A and x B approach each other, reaching the critical miscibility temperature (about 33 °C), at which the two-phase separation region disappears, and x A and x B become equal to the ammonia concentration x O (= y O ≈ 32% by mass) at the azeotropic point O at the critical miscibility temperature. Therefore, in the ammonia - propane mixed system, by introducing liquefied ammonia and liquefied propane into the sealed mixing container 16 at a charging composition ratio corresponding to an arbitrary liquid-phase composition (ammonia concentration x C ) within the two-phase separation region, and maintaining the liquid-phase temperature in the sealed mixing container 16 at a predetermined constant value from a low temperature below 0 °C to the critical miscibility temperature (about 33 °C), the ammonia concentrations of the upper layer and the lower layer are, respectively, within the range from near 0% by mass to a predetermined value x O (= y O ) of the ammonia concentration x A at the azeotropic point O at the critical miscibility temperature (about 33 °C), and from the ammonia concentration x O (= y O ) at the azeotropic point O at the critical miscibility temperature (about 33 °C) to a predetermined value x B within the range from near 100% by mass.They can be controlled respectively. As a result, the upper layer and / or the lower layer having these compositions can be discharged from the liquid phase discharge lines 221 and / or 222 respectively as the ammonia mixed fuel of the single-phase solution. Also, as a special situation, the raw materials ammonia and propane are introduced into the mixing sealed container 16 at the introduction composition ratio equal to the azeotropic composition x O (=y O ≒ 32% by mass), respectively, stirred and mixed. When the liquid phase temperature is maintained at the critical azeotropic temperature (about 33 °C) or higher by the temperature adjustment mechanism, the liquid phase of the mixture in the mixing sealed container 16 becomes a single-phase solution of the above azeotropic composition. Since the composition of the vapor when evaporating from this liquid phase is always the same azeotropic composition as the liquid phase, regardless of the progress of evaporation accompanying the discharge of the liquid phase, while maintaining the liquid phase composition at the above azeotropic composition, the total amount of the liquid phase in the mixing sealed container 16 can be discharged from the liquid phase discharge line 22 (221) as the ammonia mixed fuel of the single-phase solution. According to the manufacturing apparatus 10 of the present embodiment, not only the ammonia - propane system described above, but also other liquefied petroleum gas component hydrocarbon species in which the mixture with ammonia similarly exhibits the azeotropic gas - liquid equilibrium of liquid - phase two - phase separation, and liquefied petroleum gas which is a mixture of them as a combustion improver, although there are differences in the temperature range, pressure range, and composition range for two - phase separation, by the same apparatus and method, as in the case of the above ammonia - propane system, while controlling the discharge composition, the liquid phase of the mixture in the mixing sealed container 16 can be discharged as the ammonia mixed fuel. However, as described above, with the discharge of the above ammonia mixed fuel, the gas - liquid interface of the mixture in the mixing sealed container 16 and the interface between the upper and lower layers during liquid - phase separation descend, reaching the discharge port position in the mixing sealed container of the liquid phase discharge lines 22, 221, 222, and it is necessary to pay attention that foreign phases may be mixed into the ammonia mixed fuel, and the evaporation of the mixture proceeds, thereby the composition of the discharged ammonia mixed fuel may change.

[0076] In the manufacturing apparatus 10 of one embodiment, in addition to the above-described configuration shown in FIGS. 2 and 3(a) and (b), as shown in FIG. 4, the nitrogen gas is introduced into the gas phase portion in the mixing sealed container 16 at a discharge pressure equal to or higher than the saturated vapor pressure of the mixture in the mixing sealed container 16. A nitrogen gas introduction line 30b is provided. Also in FIG. 4, when having the same configuration and operation as the configuration parts shown in FIG. 2, the same reference numerals are given and the description thereof is omitted. Thereby, while suppressing the change in the liquid phase composition due to the progress of the evaporation of the mixture in the mixing sealed container 16 accompanying the discharge of the ammonia mixed fuel, it becomes possible to quickly discharge the ammonia mixed fuel. This embodiment can be applied to both the case where the liquid phase of the mixture in the mixing sealed container 16 becomes a single phase and the case of two-phase separation (separation into upper and lower layers). FIG. 4 shows the former form. The nitrogen gas introduction line 30b is led from a storage container such as a general pressurized nitrogen gas cylinder filled with an internal pressure of about 14.7 MPa. Also, if having the same pressure, as shown in FIG. 4, it may be branched from the piping of the nitrogen gas introduction mechanism 30. The nitrogen gas introduction line 30b is provided with a nitrogen gas pressure reducing valve 30c, a nitrogen gas pressure gauge 30d, and a nitrogen gas regulating valve 30e between the upstream side thereof and the mixing sealed container 16. The nitrogen gas led by the nitrogen gas introduction line 30b is depressurized by the pressure reducing valve 30c so that the indicated value of the nitrogen gas pressure gauge 30d becomes a pressure equal to or higher than the saturated vapor pressure of the mixture in the mixing sealed container 16 (for example, about the saturated vapor pressure + 0.05 to 0.1 Mpa). When the liquid phase of the mixture is discharged from the mixing sealed container 16, in conjunction with the opening of the liquid phase discharge valves 22a, 22a1, 22a2, the nitrogen gas regulating valve 30e is opened, and the mixture is discharged as ammonia mixed fuel from the liquid phase discharge line in a form of being forcibly pushed out by the nitrogen gas introduced from the gas phase side. These valve operations are controlled by the control device 32. When discharging the ammonia mixed fuel by introducing nitrogen gas as described above, in the gas phase part inside the mixing sealed container 16, diffusion and dilution of the evaporation gas from the mixture inside the container by the introduced nitrogen occur, thereby causing a deviation in the gas-liquid equilibrium at the gas-liquid interface. Since the evaporation of the gas from the liquid phase continues even during the discharge of the liquid phase as described above, strictly speaking, the composition change of the liquid phase can occur. However, substantially, the composition change of the liquid phase is reduced. In particular, when the ammonia concentration in the mixture is relatively low and the concentration of the combustion aid (liquefied petroleum gas or its component hydrocarbon species) is high, the specific gravity of the evaporation gas of these mixtures becomes larger than that of nitrogen gas, and the evaporation gas tends to stay near the gas-liquid interface below the gas phase part. Therefore, the deviation of the gas-liquid equilibrium is suppressed, and the composition change of the above-mentioned ammonia mixed fuel is suppressed. Further, the longer the container shape of the mixing sealed container 16 is in the vertical direction and the larger the introduction flow rate of nitrogen gas is, the closer the discharge of the internal fluid approaches the so-called "plug flow", and the convection and diffusion dilution of the above-mentioned nitrogen gas and evaporation gas are less likely to occur. Therefore, the above-mentioned composition change is suppressed.

[0077] In addition to the above-described configuration shown in FIG. 2, the manufacturing apparatus 10 of one embodiment is configured such that the raw materials ammonia and combustion aid can be continuously introduced into the mixing sealed container 16 through the introduction lines 18 and 20 against the saturated vapor pressure of the mixture in the mixing sealed container 16 at a flow rate equal to the composition ratio and flow rate of the liquid phase discharged through the liquid phase discharge line 22. Thus, the quantitative introduction mechanism of ammonia and the combustion aid is configured. An example of this embodiment is shown in FIG. 5. Also in FIG. 5, when having the same configuration and operation as the configuration parts shown in FIG. 2, the same reference numerals are given and the description thereof is omitted. With these configurations, while maintaining the height position of the gas-liquid interface of the mixture inside the mixing sealed container 16 and, when the liquid phase of the mixture undergoes two-phase separation, the height position of the interface between the upper and lower layers constant, and continuously discharging the liquid phase with a constant composition as the ammonia mixed fuel becomes possible. This embodiment can also be applied to both cases where the liquid phase of the mixture inside the mixing sealed container 16 is a single phase and cases where two-phase separation (separation into upper and lower two layers) occurs. FIG. 5 shows a form of discharging both of the upper and lower two layers separated by phase separation among the latter cases. In this embodiment, as the equipment included in the quantitative introduction mechanism, in addition to each component equipment shown in FIG. 2, as shown in FIG. 5, against the saturated vapor pressure of the mixture in the sealed mixing container 16, in order to be able to introduce liquefied ammonia of the raw material and the combustion promoter, liquid feed pumps 18d and 20d are respectively provided in the ammonia introduction line 18 and the combustion promoter introduction line 20. As these liquid feed pumps, those with a high head described above are selected. Further, through the liquid phase discharge lines 22, 221, 222, discharge flow meters 22b, 22b1, 22b2 for measuring the flow rate of the liquid phase part discharged as ammonia mixed fuel from inside the sealed mixing container 16, and composition evaluation means 22c, 22c1, 22c2 for evaluating the composition (ammonia concentration, etc.) of the liquid phase part are provided in the liquid phase discharge lines 22, 221, 222. These may be on either the upstream or downstream side of the liquid phase discharge valves 22a, 22a1, 22a2. When discharging the ammonia mixed fuel, the liquid phase discharge valves 22a, 22a1, and 22a2 are opened, and at the same time as the liquid phase discharge is started, the control device 32 starts receiving the discharge flow rate through the liquid phase discharge lines 22, 221, 222 measured by the discharge flow meters 22b, 22b1, 22b2, and the liquid phase composition measured by the composition evaluation means 22c, 22c1, 22c2. From these, the flow rates of ammonia and the combustion promoter in the discharged liquid phase through the liquid phase discharge lines 22, 221, 222 are calculated respectively. Further, so that the calculated discharge flow rates of ammonia and the combustion promoter are equal to the introduction flow rate values of the liquefied ammonia and the combustion promoter of the raw materials introduced into the mixing sealed container 16 measured by the flow meters 18a and 20a respectively, the output of the liquid feed pumps 18d and 20d, and / or the opening degrees of the regulating valves 18c and 20c are controlled by the control signal transmitted by the control device 32. In this process, the mixing and stirring of the liquid phase of the mixture in the mixing sealed container 16 and the temperature control are continued as they are. According to these controls, the height positions of the gas-liquid interface and the upper and lower layer interfaces of the mixture in the mixing sealed container 16 are maintained constant, and the composition and saturated vapor pressure of the gas-liquid phase are also kept constant. Therefore, even if the liquid phase discharge progresses, the original gas-liquid equilibrium state is maintained as it is, and evaporation into the gas phase does not occur, so the liquid phase composition is also kept constant. For this reason, the ammonia mixed fuel can be produced and continuously discharged with a constant composition.

[0078] In the continuous production of ammonia mixed fuel with a constant composition by continuously introducing the above raw materials, the composition evaluation means 22c, 22c1, 22c2 are preferably those that can be quickly measured and evaluated in-line in the liquid phase discharge line. For example, based on respective predetermined calibration methods (calibration curves), the evaluation of the absorbance intensity in the infrared absorption band of each component such as N-H stretching vibration (in the case of ammonia quantification) or C-H stretching vibration (in the case of hydrocarbon quantification) by a Fourier transform infrared absorption spectrometer, the refractive index of the discharged liquid phase measured by a refractometer, and the concentration evaluation means of ammonia or a combustion aid based on each of the sonic velocity measurements by ultrasonic irradiation using an ultrasonic densitometer, etc. can be mentioned, but are not particularly limited thereto. The data measured by such composition evaluation means is converted into the concentration of ammonia or a combustion aid by the calibration method built into the composition evaluation means itself, or is transmitted to the control device 32 as the measurement data itself, and the latter is converted into the concentration of ammonia or a combustion aid in the control device 32 and then multiplied by the flow rate values of the liquid phase discharge lines 22, 221, 222 transmitted from the discharge flow meters 22b, 22b1, 22b2, whereby the respective discharge flows of ammonia and the combustion aid are calculated. Incidentally, if the relationship between the initial introduction amounts of liquefied ammonia and the combustion aid into the mixing sealed container 16 and the liquid phase composition before the discharge of the liquid phase is known, the liquid phase composition can be determined from the respective initial introduction amounts, and thus the above composition evaluation means 22c, 22c1, 22c2 can also be omitted.

[0079] As shown in FIGS. 2, 3(a) and (b), 4, and 5, the manufacturing apparatus 10 of one embodiment includes a surfactant storage container 26 for storing a surfactant, a surfactant introduction line 28, and a liquid feed pump 28d. The surfactant introduction line 28 connects the surfactant storage container 26 and the mixing sealed container 16. Since the saturated vapor pressure of the surfactant introduction line 28 is low, it is not spontaneously introduced into the mixing sealed container 16, and thus is supplied from the surfactant storage container 26 to the mixing sealed container 16 using the liquid feed pump 28d. A flow meter 28a and regulating valves 28b and 28c configured to introduce a predetermined amount of the surfactant into the mixing sealed container 16 are provided as a quantitative introduction mechanism for the surfactant in the surfactant introduction line 28. The control device 32 receives the measurement result by the flow meter 28a, generates a control signal for controlling the opening degrees of the regulating valves 28b and 28c, and sends the generated control signal to the regulating valves 28b and 28c. However, as will be described later, when the state of the surfactant is a viscous slurry or mud, the flow meter 28a and the regulating valves 28b and 28c need to be of a specification that is not easily clogged and is adapted thereto. Further, as will be described later, a liquid feed pump 28d adapted to the transfer of a viscous slurry or mud-like surfactant needs to be adopted. Also, when it is difficult to perform quantitative control by opening and closing the regulating valves 28b and 28c, the discharge amount of the liquid feed pump 28d itself is controlled by the control signal generated by the control device 32, whereby quantitative supply is achieved. That is, the liquid feed pump 28d is also included in the quantitative introduction mechanism of the surfactant. Further, the nitrogen gas introduction mechanism 30 replaces the gas present in the surfactant introduction line 28 as necessary from an explosion-proof perspective when starting up the manufacturing apparatus 10 and after completion of the production of the ammonia mixed fuel. For this purpose, a nitrogen gas introduction valve 30a for introducing a predetermined amount of nitrogen gas into the surfactant introduction line 28 is provided. The opening degree of this nitrogen gas introduction valve 30a is controlled by the control device 32. Therefore, in the mixing sealed container 16, the surfactant is stirred and mixed with the liquid ammonia and the combustion improver by the stirrer 24 so that the mixture containing the surfactant is discharged from the liquid phase discharge line 22. Thus, by using the surfactant, an ammonia mixed fuel in which polar ammonia and non-polar combustion improver are in an emulsion state can be easily produced.

[0080] When the combustion improver is the liquefied petroleum gas or its component hydrocarbon species described above, at least a part of it is miscible with ammonia near room temperature (25°C) in the liquid phase in the gas-liquid equilibrium state. However, even for the part that does not miscible and phase-separates, it can be emulsified by adding a surfactant. As the surfactant used for emulsifying the ammonia mixed fuel, as described above, at least one nonionic surfactant (A) having a high ability to form micelles in a two-dimensional arrangement at the interface between the two liquid phases phase-separated in the ammonia mixed fuel, and at least one ionic surfactant (B) that ionizes at the interface and has a high ability to electrostatically repel the micelles to prevent contact and fusion are preferably included. As these nonionic surfactant (A) and ionic surfactant (B), those having the molecular structure described above can be preferably used. When using these mixed surfactants, it is preferable that they are sufficiently mixed and dispersed before being stored in the surfactant storage container. The above surfactants are generally in a liquid or solid state near room temperature (25°C). Ionic surfactants and non-ionic surfactants with a long-chain alkyl group having a large number of carbon atoms (long chain length) often become solid near room temperature (25°C). After mixing the above non-ionic surfactant (A) and the ionic surfactant (B), a liquid state or a stable slurry state in which the solid content is not likely to settle is obtained. When using a mixed surfactant system having sufficient fluidity during introduction, it can be introduced into the sealed mixing container 16 by the surfactant introduction system (surfactant storage container 26, surfactant introduction line 28, and liquid feed pump 28d) shown in Fig. 2. On the other hand, when the above mixed surfactant system is in a state of being solid or having insufficient fluidity close to it and is difficult to introduce as it is, it is preferable to add a small amount of any of liquefied ammonia, liquefied petroleum gas, and its component hydrocarbon species, which are raw materials of the mixed fuel, to the surfactant in advance, mix and disperse them, so as to make it into a fluid state (for example, slurry or muddy state) that can be introduced by the above surfactant introduction system. When introducing the surfactant into the sealed mixing container 16, if the mixed surfactant system is a viscous liquid or slurry or muddy state, as the liquid feed pump 28d, a type capable of quantitatively discharging and feeding such a target is adopted. Note that the surfactant itself has a low saturation vapor pressure and is almost zero near normal temperature (25°C) and atmospheric pressure. When introducing the surfactant itself in a liquid state or a stable slurry state where the solid content is difficult to settle directly into the mixing sealed container 16 by liquid feeding, when introducing the surfactant, it is necessary to avoid a situation where the surfactant cannot be introduced further due to the increase in the internal pressure of the mixing sealed container 16 caused by the prior introduction of liquefied gas such as ammonia described above. For this reason, the surfactant is preferably introduced into the mixing sealed container 16 prior to ammonia, liquefied petroleum gas which is a liquefied gas, and the combustion improver which is its component hydrocarbon species. At this time, the surfactant is quantitatively introduced by the opening and closing of the regulating valves 28b and 28c and the driving and stopping of the liquid feeding pump 28d, which are controlled by a control signal generated by the control device 32 based on the time integral value of the flow rate value measured by the flow meter 28a. On the other hand, as described above, when the surfactant is in a solid state or near it and is introduced into the mixing sealed container 16 in a slurried or muddy state by the addition of any one of liquefied ammonia, liquefied petroleum gas, and its component hydrocarbon species, it is preferably quantitatively introduced in conjunction with the introduction of any one of the same raw material-based liquefied ammonia, raw liquefied petroleum gas, and its component hydrocarbon species.

[0081] Even when manufacturing an ammonia mixed fuel emulsified by the introduction of a surfactant when the combustion improver is liquefied petroleum gas or a component hydrocarbon species of liquefied petroleum gas, basically, the manufacturing apparatus 10 shown in FIGS. 2, 3(a), (b), 4, and 5 can be suitably used according to conditions such as composition and mixing temperature. For example, in the ammonia - propane based mixture described above, due to the effect of emulsification by the addition and mixing of the surfactant, the composition range and temperature range that separate into upper and lower layers change compared to the case where no surfactant is added. However, even when emulsified by the addition of the surfactant, the fact that there is a composition range and temperature range that separate into upper and lower layers, and that it becomes a single layer due to an increase in temperature, is essentially the same as the case where no surfactant is added. Therefore, for example, by using the manufacturing apparatus 10 having the configuration shown in FIG. 2 (the apparatus in which the discharge port position of the liquid phase discharge line 22 is at the bottom surface inside the mixing sealed container 16), if the composition and temperature conditions are such that the liquid phase of the mixture forms a single layer, that single layer, or when it is separated into upper and lower layers, the lower layer, can be discharged as an emulsified ammonia mixed fuel by performing the same operations as in the case where no surfactant is added. Further, for example, by using the manufacturing apparatus 10 having the configuration shown in FIG. 3(b) (the apparatus in which the discharge port positions of the liquid phase discharge lines 221 and 222 are respectively slightly above the bottom surface of the upper layer of the upper and lower layers of the mixture inside the mixing sealed container 16 and at the bottom surface of the container), the upper layer and / or the lower layer of the liquid phase separated into upper and lower layers can be discharged as an emulsified ammonia mixed fuel. Further, by using the manufacturing apparatus 10 of FIG. 4 having the nitrogen gas introduction line 30b, it is possible to rapidly discharge as an emulsified ammonia mixed fuel while suppressing the composition change accompanying the progress of the liquid phase discharge.

[0082] Furthermore, according to the configuration in which the raw material ammonia, the combustion aid, and the surfactant are continuously introduced into the mixing sealed container 16 at an introduction flow rate equal to the discharge flow rate as shown in FIG. 5, the upper layer and / or the lower layer of the liquid phase separated into upper and lower layers can be continuously manufactured and discharged as an emulsified ammonia mixed fuel while suppressing the composition change accompanying the progress of the liquid phase discharge. Here, in the manufacturing apparatus 10 of FIG. 5, in addition to the quantitative introduction mechanism for ammonia and the combustion aid (the mechanism including the liquid feed pumps 18d, 20d, the discharge flow meters 22a, 22a1, 22a2, the liquid phase composition evaluation means 22b, 22b1, 22b2, and the control device 32) configured for the above purpose, it is equipped with a quantitative introduction mechanism for the surfactant (including the liquid feed pump 28d) configured to introduce the surfactant into the mixing sealed container 16 at an introduction flow rate equal to the discharge flow rate. Here, since the liquid feed pump 28d needs to be introduced against the saturated vapor pressure of the mixture inside the mixing sealed container 16, the same type as the high-lift liquid feed pumps for liquefied ammonia and the combustion aid described above, which requires the same thing, is selected. In this embodiment, the control device 32 calculates the concentration of the surfactant in the ammonia mixed fuel from the respective amounts of ammonia, the combustion aid, and the surfactant previously introduced as raw materials into the mixing sealed container 16. Further, the control device 32 receives the measured value of the discharge flow rate of the ammonia mixed fuel measured by the discharge flow meters 22a, 22a1, 22a2 from the start time of discharging the ammonia mixed fuel, and multiplies this discharge flow rate by the concentration of the surfactant to obtain the discharge flow rate of the surfactant discharged through the liquid phase discharge lines 22, 221, 222. The control device 32 transmits a control signal for adjusting the output of the liquid feed pump 28d and the opening degrees of the regulating valves 28b and 28c so as to continuously and quantitatively introduce the surfactant from the surfactant storage container 26 into the mixing sealed container 16 at a flow rate equal to this discharge flow rate.

[0083] Also, by partially changing the configurations of FIGS. 2, 4, and 5 as described later, instead of using liquefied petroleum gas as (a) and at least one hydrocarbon species contained as a component in the liquefied petroleum gas as the combustion aid as described above, (a) at least one of naphtha, gasoline, kerosene, and light oil, and (b) at least any one of the component hydrocarbon species of at least one of naphtha, gasoline, kerosene, and light oil can be used to produce the ammonia mixed fuel. In this case, the sealed container 14 for storing the combustion aid is a container for storing at least one of naphtha, gasoline, kerosene, and light oil, or at least one hydrocarbon species contained as a component therein. These hydrocarbon raw materials that are liquid near normal temperature (25°C) and near atmospheric pressure are easier to ignite because their ignition temperatures are lower than that of ammonia, and they have a higher combustion rate (about 5 to 7 times that of ammonia in laminar combustion rate) and are easier to burn than ammonia. Therefore, naphtha, gasoline, kerosene, and light oil, and the hydrocarbon species contained as their components can also be used as the combustion aid for ammonia. When using naphtha, gasoline, kerosene, and light oil, which are liquids near normal temperature (25°C) and near atmospheric pressure, and combustion aids that are hydrocarbon species of these components, since the saturated vapor pressure of the combustion aid in the sealed container 14 for storing the combustion aid is almost zero near normal temperature (25°C), the liquid phase is not discharged by the saturated vapor pressure and does not spontaneously flow into the sealed mixing container 16. Therefore, a liquid delivery pump 20d for supplying the above combustion aid from the sealed container 14 for storing the combustion aid to the sealed mixing container 16 needs to be further provided in the combustion aid introduction line 20. At this time, the combustion aid metering introduction mechanism also includes the above liquid delivery pump 20d, and its drive and output are controlled by a control signal generated by the control device 32. When this liquid delivery pump is provided, during the metered supply of the combustion aid, these liquid delivery pumps are output-controlled or driven or stopped by a control signal generated by the control device 32 in conjunction with the opening or opening / closing of the regulating valves 20b and 20c. When introducing naphtha, gasoline, kerosene, gas oil, and combustion improvers in the case of these component hydrocarbon species, and surfactants described later into the mixing sealed container 16 by liquid feeding using the liquid feed pump 20d, when introducing these, it is necessary to avoid a situation where they can no longer be introduced due to the increase in the internal pressure of the mixing sealed container 16 caused by the prior introduction of ammonia, which is the liquefied gas described above. For this reason, especially when not using a liquid feed pump with a particularly high lift, naphtha, gasoline, kerosene, gas oil, and combustion improvers in the form of these component hydrocarbon species, and surfactants are preferably introduced into the mixing sealed container 16 prior to ammonia. In many cases, temperature adjustment is not particularly required during the introduction. However, when introducing ammonia subsequently, as described above, since the saturated vapor pressure of the mixture in the mixing sealed container 16 must always be lower than the internal pressure (saturated vapor pressure of ammonia) of the ammonia storage sealed container 12, the temperature of the liquid phase of the mixture in the mixing sealed container 16 needs to be maintained at a predetermined temperature such that its saturated vapor pressure becomes sufficiently low. Also, as described above, when the surfactant is in a solid state or a state close thereto, it is preferably introduced into the mixing sealed container 16 in a slurried or muddy state by the addition of any of liquefied ammonia, naphtha, gasoline, kerosene, gas oil, and these component hydrocarbon species. In that case, it is preferably quantitatively introduced in conjunction with the introduction of any of liquefied ammonia, naphtha, gasoline, kerosene, gas oil, and these component hydrocarbon species, and the component hydrocarbon species of the same raw material system, respectively.

[0084] When the combustion improver is at least one of naphtha, gasoline, kerosene, gas oil, or their component hydrocarbon species, similar to the case of liquefied petroleum gas and its component hydrocarbon species described above, when no surfactant is added, in the equilibrium state, it can occur in both cases: being separated into two layers, a phase mainly composed of polar liquefied ammonia and a phase mainly composed of the combustion improver, and becoming a homogeneous solution as a whole. At that time, similar to the case of liquefied petroleum gas and its component hydrocarbon species, with the increase in temperature, it changes from a two-phase separation state to a homogeneous solution state. Furthermore, the critical miscibility temperature described above also exists, and above this temperature, it becomes completely miscible in any composition. However, when the combustion improver is naphtha, gasoline, kerosene, gas oil, and their component hydrocarbon species, the mixed fuel with liquefied ammonia generally does not show azeotropic behavior, and its saturated vapor pressure is approximately equal to or lower than the saturated vapor pressure of pure ammonia at the same temperature. When it is separated into two layers, since the specific gravity of naphtha, gasoline, kerosene, gas oil, and their component hydrocarbon species is all greater than the specific gravity of liquefied ammonia, contrary to the case of liquefied petroleum gas and its component hydrocarbon species, in a sealed container, the phase mainly composed of these combustion improvers becomes the lower layer of the phase mainly composed of liquefied ammonia.

[0085] Even when the combustion improver is naphtha, gasoline, kerosene, gas oil, or their component hydrocarbon species, if it is desired to dissolve the combustion improver and / or ammonia into the other liquid phase above the solubility determined by the gas-liquid-liquid equilibrium described above, emulsification by adding an appropriate surfactant is necessary. In particular, when the combustion improver is kerosene, gas oil, or their component hydrocarbons, in the low temperature range from near room temperature (25 °C) where the vapor pressure can be kept low to about 50 °C, the solubility of both the combustion improver and / or ammonia remains at a low concentration of about 5 mass% or less, so the addition of a surfactant becomes important. At that time, the solubility of liquefied ammonia and the combustion improver that can be mixed and dispersed is almost dominated by the performance of the surfactant and its addition amount. For this reason, it is preferable to add a sufficient amount of a suitable surfactant so that the whole mixture becomes a uniformly emulsified layer. When the addition amount of the surfactant is small, it is preferable that the transiently emulsified part is quickly used for combustion before separating into the upper and lower two layers. Or, after being stored in a sealed container for storage described later for a certain period, it may be used for combustion after being returned to an emulsified state where the whole is well dispersed by re-stirring and mixing. Incidentally, when using naphtha, gasoline, or their component hydrocarbon species (especially aromatic hydrocarbon species) which have relatively high compatibility with ammonia even without adding a surfactant as a combustion improver, the addition of a surfactant may become unnecessary. In that case, the surfactant introduction system (surfactant storage container 26, surfactant introduction line 28, flow meter 28a, regulating valves 28b, 28c, and liquid feed pump 28d) can be omitted. Even when the combustion improver is naphtha, gasoline, kerosene, gas oil, or their component hydrocarbon species, the liquid phase discharge line 222 for discharging the upper layer part of the two-phase separated liquid phase shown in FIGS. 3(a), (b) and FIG. 5, and the equipment attached thereto (liquid phase discharge valve 22a2, discharge flow meter 22b2, and composition evaluation means 22c2) can also be used to discharge the upper layer and / or lower layer of the two-phase separated liquid phase as ammonia-mixed fuel.

[0086] In order to produce a homogeneous and stable ammonia mixed fuel in which the combustion improver contains at least one of naphtha, gasoline, kerosene, gas oil, or their component hydrocarbon species, basically, a mixed surfactant having a molecular structure common to that of liquefied petroleum gas and its component hydrocarbon species can be preferably used as the combustion improver. However, as described above, the chain length of the long-chain alkyl group or alkenyl group of the surfactant is often preferably longer than that of liquefied petroleum gas and its component hydrocarbon species. When a sufficient amount of such an appropriate mixed surfactant is added and stirred and mixed, the phase separation part (ammonia or combustion improver) is dispersed into the other phase by emulsification, and the whole of the mixed fuel can be homogenized. At that time, it is preferable to maintain the temperature range such that the emulsifying performance of the surfactant is sufficiently exhibited, in the same manner as in the case where the combustion improver is liquefied petroleum gas and its component hydrocarbon species. If the ammonia mixed fuel produced as described above is taken out and burned in that state, it exhibits high combustibility. In addition, even when the combustion improver is naphtha, gasoline, kerosene, gas oil, or their component hydrocarbon species, when using the production apparatus of FIG. 2, when discharging the liquid phase part of the emulsified mixture from the liquid phase discharge line 22, the composition change of the discharged liquid phase proceeds in the same manner as in the case where the combustion improver is liquefied petroleum gas or its component hydrocarbon species. That is, as the liquid phase is discharged, the gas-liquid interface of the mixture in the sealed mixing container 16 descends, and evaporation (boiling) from the liquid phase to the gas phase of the mixture occurs. At that time, regardless of the liquid phase composition, the ammonia concentration in the evaporated gas is higher than the ammonia concentration in the liquid phase, so the ammonia concentration in the liquid phase decreases as the liquid phase discharge progresses. In contrast, if the manufacturing apparatus 10 of FIG. 4 (the apparatus including the combustion improver liquid feed pump 20d not shown) is used, similar to the case where the combustion improver is liquefied petroleum gas or its component hydrocarbon species described above, by the pressure introduction of nitrogen into the gas phase in the mixing sealed container 16, it is possible to rapidly discharge as ammonia mixed fuel while suppressing the above composition change in the discharged liquid phase. Further, if the manufacturing apparatus 10 of FIG. 5 (the liquid phase discharge line 222 and the equipment attached thereto are often omitted) is used, by continuously introducing the liquefied ammonia, combustion improver, and surfactant of the raw materials at flow rates equal to the respective discharge flow rates of ammonia, combustion improver, and surfactant in the discharged liquid phase (the pumps for these liquid feeds are selected from those with the above-described high lift), it is possible to continuously discharge as ammonia mixed fuel without causing the above composition change in the discharged liquid phase. As described above, even when the combustion improver is any one of naphtha, gasoline, kerosene, gas oil, and their component hydrocarbon species, if the manufacturing apparatuses 10 shown in FIGS. 2 and 4 (these include the combustion improver liquid feed pump 20d not shown) and FIG. 5 are used, ammonia mixed fuel can be manufactured with their respective utilities. At that time, in addition to the quantitative introduction of liquefied ammonia, combustion improver, and surfactant, and the temperature adjustment during stirring and mixing, a series of controls including those described above are basically performed based on the control signal of the control device 32, similar to the case where the combustion improver is any one of liquefied petroleum gas and its component hydrocarbon species described above.

[0087] FIG. 6 is a diagram showing an example of the configuration of a manufacturing apparatus 10 according to another embodiment different from the configuration of the manufacturing apparatus 10 shown in FIG. 2. The example shown in FIG. 6 shows an apparatus form when using an alcohol for raw materials having 3 or less carbon atoms in the molecule as in the above (c), such as methanol, as a combustion improver. Since the alcohol for raw materials has a lower ignition temperature than ammonia, it is easy to ignite, and since it has a higher combustion rate (about 6 to 7 times that of ammonia in laminar combustion rate), it is easy to burn. Also, compared with conventionally used liquid fossil fuels such as heavy oil, light oil, kerosene, and gasoline, the CO2 generation per calorific value during combustion is also small. For this reason, the alcohol for raw materials is preferable as a combustion improver for ammonia. Further, since the alcohol for raw materials has polarity and further forms a hydrogen bond with ammonia, in the gas-liquid equilibrium state, the liquid phase portion of the mixed fuel with ammonia becomes a solution state that is compatible in a wide composition range and temperature range. At that time, the mixed fuel does not exhibit azeotropic behavior, and its saturated vapor pressure becomes a value lower than the saturated vapor pressure of pure ammonia at the same temperature. For this reason, a surfactant is not often required, and in the manufacturing apparatus 10, the surfactant introduction system (surfactant storage container 26, surfactant introduction line 28, flow meter 28a, regulating valves 28b, 28c, and liquid feed pump 28d) can be omitted. Also, if the external environmental temperature is normal temperature (25°C) or in the vicinity thereof, for example, approximately from 0°C to 40°C, in many cases, it is not necessary to perform temperature control particularly during stirring and mixing. For this reason, when the combustion improver is an alcohol for raw materials, the configuration of the manufacturing apparatus 10 can be simplified. In addition, the reference numerals of the components shown in FIG. 6 are also given the same reference numerals and their descriptions are omitted when they have the same configuration and function as the components shown in FIG. 2. In the sealed container 14 for storing the combustion improver shown in Fig. 6, the alcohol for raw materials is stored. The alcohol for raw materials has a low saturated vapor pressure and is not discharged at the saturated vapor pressure inside the sealed container 14 for storing the combustion improver, and is not spontaneously introduced into the sealed container 16 for mixing, so a liquid feed pump 20d is provided. By means of the liquid feed pump 20d, the alcohol for raw materials is supplied from the sealed container 14 for storing the combustion improver to the sealed container 16 for mixing. Also, when introducing the alcohol for raw materials which is a liquid near normal temperature (25°C) and near atmospheric pressure, it is not particularly necessary to perform temperature adjustment. However, when introducing liquefied ammonia subsequently, if the liquid feed pump 20d does not have a particularly high head, the temperature inside the sealed container 16 for mixing needs to be maintained so that the internal gas phase pressure inside the sealed container 16 for mixing is always lower than the saturated vapor pressure inside the sealed container for storing the liquefied ammonia of the raw materials to be introduced hereafter.

[0088] In addition, even when the combustion improver is the alcohol for raw materials, when using the production apparatus of Fig. 2, when discharging the liquid phase portion of the mixture in a solution state from the liquid phase discharge line 22, the change in the composition of the discharged liquid phase proceeds in the same manner as when the combustion improver is liquefied petroleum gas or its component hydrocarbon species. That is, as the liquid phase is discharged, the gas-liquid interface of the mixture inside the sealed container 16 for mixing descends, and evaporation (boiling) of the mixture from the liquid phase to the gas phase occurs. At that time, regardless of the liquid phase composition, the ammonia concentration in the evaporated gas is higher than the ammonia concentration in the liquid phase. Therefore, as the liquid phase discharge progresses, the ammonia concentration in the liquid phase decreases. On the other hand, if the manufacturing apparatus 10 shown in FIG. 4 (equipped with a combustion aid liquid feed pump 20d not shown) is used, similar to the case where the combustion aid is liquefied petroleum gas or its component hydrocarbon species described above, by the pressure introduction of nitrogen into the gas phase in the mixing sealed container 16, it is possible to quickly discharge the ammonia mixed fuel while suppressing the above composition change in the discharged liquid phase. Also, if the manufacturing apparatus 10 shown in FIG. 5 (the liquid phase discharge line 222 and the equipment attached thereto are omitted) is used, by continuously introducing the liquefied ammonia and the combustion aid of the raw materials at a flow rate equal to the respective discharge flow rates of ammonia and the combustion aid in the discharged liquid phase (for these liquid feed pumps, those with the above-mentioned high lift are selected), it is possible to continuously discharge the ammonia mixed fuel without causing the above composition change in the discharged liquid phase. As described above, even when the combustion aid is raw material alcohol, if the manufacturing apparatus 10 of FIG. 2, FIG. 4 (these are equipped with a combustion aid liquid feed pump 20d not shown and the surfactant introduction system is omitted), and FIG. 5 (the liquid phase discharge line 222 and the equipment attached thereto, and the surfactant introduction system are omitted) is used, the ammonia mixed fuel can be manufactured with their respective utilities. At that time, in addition to the quantitative introduction of liquefied ammonia and the combustion aid and the temperature adjustment during stirring and mixing, a series of controls including those described above are basically carried out based on the control signal of the control device 32, similar to the case where the combustion aid is either liquefied petroleum gas or its component hydrocarbon species described above.

[0089] The combustion improver in the ammonia mixed fuel of one embodiment may be any one of the above (a) to (c), or may be a combination of a plurality of the above (a) to (c). For example, at least one of liquefied petroleum gas as the above (a) and hydrocarbon species which are components of liquefied petroleum gas as the above (b) and the alcohol for raw materials of (c) can be used in combination as a combustion improver. FIG. 7 is a diagram showing an example of the configuration of the manufacturing apparatus of this another embodiment, and the example shown in FIG. 7 shows the apparatus form in the case where a hydrocarbon species which is liquefied petroleum gas or a component of liquefied petroleum gas and the alcohol for raw materials are both used as a combustion improver. The reference numerals of the constituent parts shown in FIG. 7 are also given the same reference numerals and their description is omitted when they have the same configuration and operation as the constituent parts shown in FIG. 2. The manufacturing apparatus 10 includes sealed containers 141 and 142 for storing a combustion improver. The sealed container 141 for storing a combustion improver stores liquefied petroleum gas or a hydrocarbon species which is a component of liquefied petroleum gas, and the sealed container 142 for storing a combustion improver stores the alcohol for raw materials. Combustion improver introduction lines 201 and 202 extending from the sealed containers 141 and 142 for storing a combustion improver to the sealed container 16 for mixing are provided, and flow meters 20a1 and 20a2 and regulating valves 20b1, 20c1, 20b2, and 20c2 are provided in the combustion improver introduction lines 201 and 202. The control device 32 receives the measurement results by the flow meters 20a1 and 20a2, generates a control signal for controlling the opening degrees of the regulating valves 20b1, 20c1, 20b2, and 20c2, and sends the generated control signal to the regulating valves 20b1, 20c1, 20b2, and 20c2. The nitrogen gas introduction mechanism 30 is provided for replacing the gas existing in each introduction line and the sealed container 16 for mixing as necessary from the viewpoint of explosion prevention when starting up the manufacturing apparatus 10 and after completion of the production of the ammonia mixed fuel, etc., and a nitrogen gas introduction valve 30a for introducing a predetermined amount of nitrogen gas into the combustion improver introduction lines 201 and 202 is provided. The opening degree of the nitrogen gas introduction valve 30a is controlled by the control device 32.

[0090] Incidentally, the saturated vapor pressure of the alcohol for raw materials is low and is nearly zero near room temperature (25°C). Therefore, it is not discharged at the saturated vapor pressure in the closed container 142 for storing the combustion aid, and is not spontaneously introduced into the mixing closed container 16. Thus, a liquid feed pump 20d2 for supplying from the closed container 142 for storing the combustion aid to the mixing closed container 16 is provided in the combustion aid introduction line 202. When introducing the alcohol for raw materials which is a liquid near room temperature (25°C) and near atmospheric pressure, it is not particularly necessary to perform temperature adjustment. However, when introducing liquefied ammonia, liquefied petroleum gas, and hydrocarbon species of its components thereafter, if a liquid feed pump with a particularly high head is not used for these, the temperature in the mixing closed container 16 needs to be maintained so that the internal pressure of the gas phase in the mixing closed container 16 is always lower than the lowest saturated vapor pressure in the respective closed containers for storing liquefied ammonia, liquefied petroleum gas, and hydrocarbon species of its components as raw materials. In many cases, it is substantially cooling to a temperature lower than the external environment. The quantitative introduction of ammonia, liquefied petroleum gas and hydrocarbon species of liquefied petroleum gas components, and the alcohol for raw materials into the mixing closed container 16 and the temperature adjustment during the quantitative introduction are performed by the aforementioned quantitative introduction mechanism and temperature adjustment mechanism based on the control signal generated by the control device 32. As another embodiment using a combination of a plurality of (a) to (c) above as a combustion improver, the configuration shown in FIG. 5 is partially modified. Instead of the above liquefied petroleum gas or the component hydrocarbon species of liquefied petroleum gas, (a) naphtha, gasoline, kerosene, and light oil, and (b) at least any one of these component hydrocarbon species can be used as a combustion improver together with the raw material alcohol to produce an ammonia mixed fuel. In this case, for example, naphtha, gasoline, kerosene, light oil, and these component hydrocarbon species are stored in the airtight container 141 for storing the combustion improver and introduced into the airtight container 16 for mixing through the combustion improver introduction line 201. Since the saturated vapor pressures of naphtha, gasoline, kerosene, light oil, and these component hydrocarbon species are low and are almost zero near room temperature (25°C) like the raw material alcohol, they are not spontaneously introduced into the airtight container 16 for mixing, so a liquid feed pump 20d1 is also provided in the combustion improver introduction line 201. When introducing naphtha, gasoline, kerosene, light oil, and these component hydrocarbon species, and the raw material alcohol, which are liquid near room temperature (25°C) and near atmospheric pressure, it is not particularly necessary to perform temperature control. However, when introducing liquefied ammonia subsequently, the temperature in the airtight container 16 for mixing needs to be maintained so that the internal pressure in the gas phase in the airtight container 16 for mixing is always lower than the saturated vapor pressure in the airtight container for storing the raw material liquefied ammonia. Also in this case, the quantitative introduction and temperature control are performed based on the control signal of the control device 32.

[0091] When using a combination of the above-mentioned non-polar liquefied petroleum gas, naphtha, gasoline, kerosene, gas oil that is hardly miscible with liquefied ammonia, and these component hydrocarbon species (hereinafter collectively referred to as "hydrocarbons for raw materials"), liquefied ammonia, and alcohol for raw materials as a combustion improver, due to the effect of the alcohol for raw materials having an affinity for both polar liquefied ammonia and non-polar hydrocarbons for raw materials, the miscible portion increases significantly without adding a surfactant. However, depending on the mixing ratio, a surfactant may be required to homogenize by emulsification. For example, when the alcohol for raw materials is methanol, when the addition amount of methanol is approximately 10% by mass or less of the whole and liquefied ammonia is approximately 10 - 70% by mass (the remainder being hydrocarbons for raw materials), the non-polar hydrocarbons for raw materials may not completely dissolve, and in the liquid phase, the phase mainly composed of it may phase-separate. A surfactant is required to emulsify and uniformly disperse this phase-separated portion. As the surfactant at this time, the above-described mixed surfactant can also be preferably used. When the mixed surfactant is added and stirred, the ammonia mixed fuel becomes at least partially in an emulsion state. Also, depending on the mixing composition of ammonia and the combustion aid, if a sufficient amount of surfactant is added and stirred, it is also possible to make the whole in an emulsion state. At that time, since the solubility and dispersibility of the hydrocarbon for raw materials are generally improved by heating, if necessary, the temperature of the mixture in the mixing sealed container 16 is adjusted by the above-described temperature adjustment mechanism based on the control signal of the control device 32 so as to be equal to or higher than a predetermined temperature suitable for mixing and dispersion, and it is preferably stirred. Furthermore, as the above-described mixed surfactant, it is preferable to select one having an alkyl group or alkenyl group with a chain length suitable for sufficiently exhibiting the emulsifying power (emulsification ability) in that temperature range. In addition, when the above-described mixed surfactant becomes solid or in a state close to it and is difficult to introduce as it is, it is preferable to add a small amount in advance of any one of liquefied ammonia, hydrocarbon for raw materials, or alcohol for raw materials, which are raw materials of the ammonia mixed fuel, to the surfactant, mix, and disperse it to make it in a state (for example, slurry or muddy state) that can be introduced by the surfactant introduction system. On the other hand, when the total amount of liquefied ammonia and alcohol for raw materials is sufficiently large and the amount ratio of the nonpolar hydrocarbon for raw materials is small, there may be a case where it can be made into a substantially uniformly dissolved solution state without adding a surfactant. In such a case, in the production apparatus 10, the surfactant introduction system (surfactant storage container 26, surfactant introduction line 28, and liquid feed pump 28d) can be omitted.

[0092] Also, as still another embodiment using a plurality of combinations of the above (a) to (c) as the combustion aid, liquefied petroleum gas and at least one of the component hydrocarbon species of liquefied petroleum gas, and naphtha, gasoline, kerosene, light oil, and at least one of the component hydrocarbon species thereof are used together as the combustion aid, and an ammonia mixed fuel can also be produced by the same production apparatus as in FIG. 7. In this case, in Fig. 7, liquefied petroleum gas and its component hydrocarbon species, which do not require a liquid feed pump when introduced into the mixing sealed container 16, are stored in the sealed container 141 for storing the combustion improver, and naphtha, gasoline, kerosene, light oil, and their component hydrocarbon species, which require a liquid feed pump (20d2 in Fig. 5), are stored in the sealed container 142 for storing the combustion improver, and are respectively introduced into the mixing sealed container 16 through the introduction lines 201 and 202. Among these combustion improvers, namely liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and their component hydrocarbon species, the component hydrocarbon species of liquefied petroleum gas are partially miscible with liquefied ammonia in the liquid phase at the vapor-liquid equilibrium state near normal temperature (25°C), while the component hydrocarbon species of naphtha, gasoline, kerosene, and light oil, which are liquids near normal temperature (25°C) and near atmospheric pressure, are hardly miscible. Therefore, in order to produce a uniformly and stably dispersed ammonia mixed fuel, emulsification by adding a surfactant is necessary. As the surfactant at this time, the above-mentioned mixed surfactant can also be preferably used. When the mixed surfactant is added and mixed and dispersed, the ammonia mixed fuel becomes at least partially in an emulsion state. Also, depending on the mixing composition of ammonia and the combustion improver, if a sufficient amount of surfactant is added, it is also possible to make the whole in an emulsion state. At that time, since the solubility of the hydrocarbon for raw materials generally improves by heating, if necessary, while being adjusted by the above-mentioned temperature adjustment mechanism based on the control signal of the control device 32 so that the temperature of the mixture in the mixing sealed container 16 becomes equal to or higher than a predetermined temperature suitable for mixing and dispersion, it is preferably stirred. Furthermore, as the above-mentioned mixed surfactant, it is preferably selected to have an alkyl group or alkenyl group with a chain length suitable for sufficiently exhibiting the emulsifying power in that temperature range. In addition, when the above-mentioned mixed surfactant becomes solid or in a state close to it and is difficult to introduce as it is, it is preferable to add a small amount of liquefied ammonia or hydrocarbon for raw materials, which are the raw materials of the ammonia mixed fuel, to the surfactant in advance, mix and disperse them, so as to make it in a state (for example, slurry or muddy state) that can be introduced by the surfactant introduction system.

[0093] In the production of ammonia mixed fuel in each case where the combustion improver is a combination of a plurality of the above (a) to (c), when introducing each raw material component into the mixing sealed container 16, in the case of discharging based on the saturated vapor pressure in the sealed container for storing the raw materials, or when the liquid delivery pump does not have a particularly high lift, summarizing the guideline for the preferable introduction order into the mixing sealed container 16, for all introduction targets into the mixing sealed container including ammonia and the combustion improver, it is advantageous to introduce them in order from the introduction target with the lower saturated vapor pressure at the temperature in the mixing sealed container. Specifically, it is as follows. That is, first, raw material alcohols, naphtha, gasoline, kerosene, light oil, and their component hydrocarbon species, and surfactants, which are liquids with a low saturated vapor pressure near normal temperature (25°C), are introduced into the mixing sealed container 16 using a liquid delivery pump prior to ammonia, liquefied petroleum gas, and their component hydrocarbon species, which have a high saturated vapor pressure near normal temperature (25°C). Before and after the introduction of these predetermined amounts, the regulating valves 20b2, 20c2, 28b, and 28c are opened and closed, and during the introduction, each introduction amount is controlled to be a predetermined amount. Next, after the inside of the mixing sealed container 16 is sufficiently cooled by the temperature regulating mechanism, among liquefied ammonia, liquefied petroleum gas, and their component hydrocarbon species, which are liquefied gases, they are introduced into the mixing sealed container 16 in order from those with the lower saturated vapor pressure at the set temperature by discharging due to their own saturated vapor pressure. At that time, the gas phase in the mixing sealed container 16 is pre-gas replaced by the vaporized gas of the liquefied gas with the lowest saturated vapor pressure, which is introduced first. Before and after the introduction of these predetermined amounts, the regulating valves 18b, 18c, 20b1, and 20c1 are opened and closed, and during the introduction, each introduction amount is controlled to be a predetermined amount. Also, when the surfactant is in a solid state or a state close to it, which is difficult to introduce by itself, it is preferably introduced into the mixing sealed container 16 in a slurried or muddy state by adding any of liquefied ammonia, liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and their component hydrocarbon species as raw materials. In that case, they are introduced quantitatively in conjunction with the introduction of any of liquefied ammonia, liquefied petroleum gas, naphtha, gasoline, kerosene, light oil, and their component hydrocarbon species, which are raw material systems common to the fluidizing medium.After the metered introduction of each of the above raw materials is completed and all regulating valves are closed, the liquid phase inside the sealed mixing container 16 is stirred by the stirrer 24 while being temperature-controlled by the temperature control mechanism so as to be maintained within a preferred temperature range, and the ammonia mixed fuel is produced. In any of the above cases where the combustion aid is a combination of a plurality of the above (a) to (c), the metering introduction mechanism and the temperature control mechanism are configured in the same manner as those described in the description of FIG. 2, and metering introduction and temperature control are performed based on the control signal of the control device 32. Thereafter, further, depending on the liquid phase composition of the mixture, temperature control is performed based on the control signal generated by the control device 32 so as to be maintained within an appropriate temperature range as appropriate, whereby, overall, an ammonia mixed fuel in which the combustion aid is stably and uniformly dispersed can be produced.

[0094] Also, in the production of the ammonia mixed fuel in each case where the combustion aid is a combination of a plurality of the above (a) to (c) as described above, when using the production apparatus of FIG. 7, when discharging the liquid phase portion of the emulsified mixture from the liquid phase discharge line 22, the composition change of the discharged liquid phase described above progresses. That is, as the liquid phase is discharged, the gas-liquid interface of the mixture in the sealed mixing container 16 descends, and evaporation (boiling) from the liquid phase of the mixture to the gas phase occurs. At this time, since various combustion aids coexist, the evaporation gas composition becomes complicated (the components contained in the evaporation gas mainly become a mixed gas of ammonia and liquefied petroleum gas or its component hydrocarbon species and / or raw material alcohol), and the composition of the evaporation gas is different from the liquid phase composition, which is the same as in the case of using various combustion aids described above, and the liquid phase composition changes as the progress of the composition liquid phase discharge of these in the liquid phase. On the other hand, if a manufacturing apparatus is used in which the nitrogen gas introduction line 30b of the manufacturing apparatus 10 in FIG. 4 is provided in accordance with the configuration of the manufacturing apparatus 10 in FIG. 7, by pressurized introduction of nitrogen into the gas phase in the mixing sealed container 16, it is possible to rapidly discharge the ammonia mixed fuel while suppressing the above-described compositional change in the discharged liquid phase. Further, if a manufacturing apparatus is used in which the continuous metering introduction mechanism of the raw materials of the manufacturing apparatus 10 in FIG. 5 is provided in accordance with the configuration of the manufacturing apparatus 10 in FIG. 7, the liquefied ammonia, various combustion aids, and surfactant of the raw materials are continuously metered and introduced at a flow rate equal to the respective discharge flow rates of ammonia, various combustion aids, and surfactant in the discharged liquid phase (for these liquid feeding pumps, those with the above-described high head are selected), and it is possible to continuously discharge the ammonia mixed fuel without causing the above-described compositional change in the discharged liquid phase. As described above, also in the production of the ammonia mixed fuel in each case where the combustion aid is a combination of a plurality of the above (a) to (c), the manufacturing apparatus 10 in FIG. 7 and the manufacturing apparatus obtained by adding the functions of the manufacturing apparatus 10 in FIGS. 4 to 5 to the manufacturing apparatus 10 in FIG. 7 can produce the ammonia mixed fuel with their respective utilities. At that time, a series of controls including the above-described ones, in addition to the quantitative introduction of liquefied ammonia, combustion aid, and surfactant and the temperature adjustment during stirring and mixing, are also performed based on the control signal of the control device 32.

[0095] In the above, the ammonia introduction line 18, the liquid phase discharge line 22, and the mixing sealed container 16 of the manufacturing apparatus 10 are configured, and materials (such as pipes, containers, control valves, agitators, coolers, and quantitative introduction mechanisms) that come into contact with the fluid containing ammonia are made of materials that are durable against ammonia. For example, copper, alloys containing copper such as cupronickel and brass, alloys containing aluminum such as aluminum and duralumin, and alloys containing zinc such as zinc and galvanized iron are not preferable in terms of corrosion resistance against ammonia. Also, iron or steel, especially when the carbon content is high, is likely to cause stress corrosion cracking. Therefore, when adopted, it is necessary to select materials with a low carbon content and confirmed durability against ammonia. As usable materials, for example, in addition to the above-mentioned iron or steel materials with confirmed durability against ammonia, austenitic stainless steels, etc. (however, stainless steels with a relatively high nickel content are said to be likely to cause stress corrosion cracking by ammonia and require attention), ceramics such as glass and quartz, and plastics and rubbers such as polyethylene, polypropylene, polytetrafluoroethylene, chloroprene rubber, and perfluoroelastomer can be mentioned. These materials are excellent in corrosion resistance at about 60°C or lower and can be preferably used. When mixing and stirring in the mixing sealed container 16 using liquid ammonia (liquefied ammonia) or liquefied hydrocarbon for raw materials, cavitation may easily occur. Therefore, for the agitator 24, it is preferable to use a material that is also durable against erosion caused by cavitation.

[0096] According to the manufacturing apparatus 10 of one embodiment, it is preferable that the mixing sealed container 16 is provided with a mixing state evaluation apparatus configured to evaluate the mixing state of the mixture (in FIG. 2, as an example, a sight glass 29 described later is illustrated. Others are not illustrated). In this case, according to the evaluation result of the mixing state evaluation apparatus, it is preferable that the control device 32 adjusts the intensity and time of stirring and mixing by the agitator 24. In this case, the control device 32 is a stirring adjustment device that adjusts the intensity and time of stirring and mixing. As a mixing state evaluation device, for example, there is a device having at least a pressure-resistant sight glass 29 (peep window) provided in the upper layer and the lower layer part, or a fiber scope, which can observe whether the internal mixture is not separated into two phases or is in an emulsion state, and a monitor for displaying the state of the liquid through the pressure-resistant sight glass or the fiber scope. Further, as a mixing state evaluation device, a measuring instrument for evaluating differences in physical properties such as turbidity, dielectric constant, and refractive index of at least the upper layer and the lower layer of the liquid inside the mixing sealed container 16 can also be used. Furthermore, in addition to the above device configuration, the mixing state evaluation device may also be provided with a microscope capable of observing the microdispersion state of the mixing and an automatic recognition evaluation device based on artificial intelligence (AI) technology. However, when the vapor-liquid equilibrium data is known and a raw material system in a compatible composition and temperature condition is used, for example, when ammonia and an alcohol for raw material having 3 or less carbon atoms are mixed without adding a hydrocarbon for raw material, or when it is known in advance that they are almost uniformly compatible or emulsified, the mixing state evaluation device may not be necessary.

[0097] Also, when introducing liquefied ammonia into the mixing sealed container 16, as shown in FIG. 7, it is preferable that a temperature control device 18e configured to adjust the temperature of the liquid ammonia passing through the ammonia introduction line 18 to the same temperature as the internal temperature of the mixing sealed container 16 is provided in the ammonia introduction line 18. Also, when introducing liquefied petroleum gas and its component hydrocarbon species as a combustion aid into the mixing sealed container 16 through the combustion aid introduction line 201, as shown in FIG. 7, a temperature control device 20e1 configured to adjust the temperature of the combustion aid passing through the combustion aid introduction line 201 to the same temperature as the internal temperature of the mixing sealed container 16 is preferably provided in the combustion aid introduction line 201. These temperature control devices are constituted by, for example, a heat exchanger or a Peltier element. When introducing these liquefied gas raw materials, the internal pressure of the mixing sealed container 16 is temperature-controlled by the above-described temperature control mechanism to be lower than the saturated vapor pressures in the sealed containers 12 and 141 for storing liquefied ammonia and liquefied petroleum gas or its component hydrocarbon species. In many cases, this results in cooling to a temperature substantially lower than the external environment. Therefore, in many cases, the temperature control of each introduction line by the above temperature control device also results in cooling to a temperature lower than the external environment. Thereby, when these liquefied gas raw materials are introduced into the mixing sealed container 16, the internal temperature does not rise. Thus, in the mixing sealed container 16, unnecessary vaporization from these mixtures can be suppressed, preventing an increase in the saturated vapor pressure. Also, when no liquid delivery pump is provided during these introductions, if the external environment temperature is too low and the respective saturated vapor pressures inside the ammonia storage sealed container 12 and / or the combustion aid storage sealed container 141 are insufficient for their respective introductions into the mixing sealed container 16, heating devices 13 and / or 15 can be provided in the ammonia storage sealed container 12 and / or the combustion aid storage sealed container 14, and appropriately heated to increase the respective saturated vapor pressures. As the heating devices 13 and 15, for example, electric heaters or constant temperature baths containing a heating medium whose temperature is appropriately adjusted are used. Incidentally, the temperature control by the aforementioned temperature control mechanism provided in the mixing sealed container 16, and the temperature control devices 18e and 20e1 provided in the introduction lines 18 and 201, and further the heating by the heating devices 13 and 15 provided in each of the storage sealed containers 12 and 141 are controlled by the control device 32 based on the results of the thermometers 33, 18f and 20f1 provided in the mixing sealed container 16 and the introduction lines 18 and 201, respectively.

[0098] FIG. 8 is a block diagram of an example of the main part of the manufacturing apparatus 10 of one embodiment. As shown in FIG. 8, the manufacturing apparatus 10 includes a sealed container 50 for storing an ammonia mixed fuel configured to store the ammonia mixed fuel in a gas-liquid equilibrium state. The sealed container 50 for storage includes an injection port 52 into which the ammonia mixed fuel is injected, and a discharge port 54 provided at the lower part, preferably the bottom surface, of the sealed container 50 for storage and configured to discharge the ammonia mixed fuel in a liquid state to the outside. A connection mechanism 56 is provided at the injection port 52 and configured to inject the ammonia mixed fuel from the liquid phase discharge line 22 into the sealed container 50 for storage while maintaining airtightness and internal pressure. As an airtight structure, a seal mechanism (not shown) using a gasket or an O-ring or the like is provided at the injection port 52. Since the inner wall of the sealed container 50 for storage comes into contact with ammonia in the same manner as the mixing sealed container 16, the sealed container 50 for storage and the connection mechanism 56 are made of a material having corrosion resistance to ammonia. Ammonia mixed fuel supply line 60 for discharging the ammonia mixed fuel in a liquefied state to the outside is connected to the discharge port 54. A valve 58 for controlling the supply amount of the ammonia mixed fuel by the control device 32 is provided in the ammonia mixed fuel supply line 60. Discharge

[0099] ​When introducing and filling the ammonia mixed fuel from the mixing sealed container 16 into the storage sealed container 50, prior to that, in order to avoid the mixing of air or the like existing in the storage sealed container 50, it is necessary that the residual air or the like in the storage sealed container 50 is previously exhausted by vacuum exhaust through the gas phase discharge line 59, or replaced by the volatile vapor of the ammonia mixed fuel. In the former case, a vacuum pump (not shown) is connected to the ammonia mixed fuel supply line 60. With the liquid phase discharge valve 22a closed, the discharge valve 58 is opened, and after vacuum exhausting until the internal pressure of the storage sealed container 50 becomes approximately 0.01 MPa or less by the vacuum pump, the discharge valve 58 is closed. Then, the liquid phase discharge valve 22a is opened, and the ammonia mixed fuel is filled into the storage sealed container 50. In the latter case, in addition to the configuration of FIG. 9, as shown in FIG. 10 described later, it is preferable to provide a gas phase discharge line 59 for discharging the gas in the gas phase part of the storage sealed container 50 to the upper part, preferably at the topmost surface, of the storage sealed container 50 (a gas phase discharge valve 59a is provided in the gas phase discharge line 59). At this time, with the liquid phase discharge valve 22a closed, after opening the gas phase discharge valve 59a, the liquid phase discharge valve 22a is slightly opened to introduce a small amount of ammonia mixed fuel into the storage sealed container 50, and after purging the residual air or the like in the storage sealed container 50 with its volatile vapor, the gas phase discharge valve 59a is closed, whereby the storage sealed container 50 is gas replaced. Then, the liquid phase discharge valve 22a is opened, and the ammonia mixed fuel is filled into the storage sealed container 50. When filling the above ammonia mixed fuel, a temperature control device (not shown) described later is provided, and it is preferable that the inside of the storage sealed container 50 can be sufficiently cooled so that the internal saturated vapor pressure becomes approximately 0.05 to 0.1 MPa or less (to increase the filling amount into the storage sealed container 50 (reduce the volume of the gas phase part after filling)). Thereby, the ammonia mixed fuel can be efficiently filled into the storage sealed container 50 through the liquid phase discharge line 22 by the discharge based on the saturated vapor pressure of the ammonia mixed fuel in the mixing sealed container 16.

[0100] It is preferable that the storage sealed container 50 of the manufacturing apparatus 10 according to one embodiment is provided with a stirrer 63 configured to stir and mix the ammonia mixed fuel as shown in FIG. 8.

[0101] The storage sealed container 50 of the manufacturing apparatus 10 according to one embodiment is provided with a temperature control device (not shown) configured to appropriately adjust the temperature of the ammonia mixed fuel inside the storage sealed container 50. Examples of the temperature control device include a heat exchanger that adjusts the temperature of the mixing sealed container 16 by flowing a temperature control medium, or a Peltier element. The temperature control by the temperature control device is controlled by a control signal generated by the control device 32 based on the temperature measurement value of a thermometer 61 that measures the liquid phase temperature inside the storage sealed Volume container 50. This temperature control device has the following three functions, similar to the temperature control mechanism in the above-described mixing sealed container 16. The first is the cooling control of the internal temperature to ensure that the internal pressure of the storage sealed container 50 is within a temperature range that does not exceed its set pressure resistance. During this temperature control, when the internal pressure measurement value of a pressure gauge 62 that measures the internal pressure inside the storage sealed Volume container 50 is predicted by the control device 32 to reach the level of the pressure resistance, the storage sealed Volume container 50 is quickly cooled by the temperature control device. The second is the cooling control for reducing the internal pressure of the storage sealed container 50 so that the filling of the ammonia mixed fuel can be performed efficiently and smoothly as described above. The third control is to adjust the temperature of the mixture such that the entire liquid-phase portion of the mixture of ammonia and the combustion improver within the storage sealed container 50 maintaining the gas-liquid equilibrium state is within a temperature range where the ammonia and the combustion improver are in a solution state in which they are mutually dissolved or an emulsion state, according to the liquid-phase composition of the mixture. For this purpose, the storage sealed container 50 is provided with both the temperature adjusting device and the stirrer 63, and when the ammonia mixed fuel within the storage sealed container 50 is stirred and mixed by the stirrer 63, the temperature adjusting device is configured to adjust the temperature of the ammonia mixed fuel such that the entire liquid-phase portion of the ammonia mixed fuel is within a temperature range where the ammonia and the combustion improver are in a solution state in which they are mutually dissolved or an emulsion state, according to the liquid-phase composition of the ammonia mixed fuel. Here, as the "temperature range where the ammonia and the combustion improver are in a solution state in which they are mutually dissolved or an emulsion state", a temperature range suitable for homogenization by compatibility or emulsification in the ammonia mixed fuel of each mixed raw material system described above is selected. This temperature control is also performed by the temperature adjusting device based on the control signal generated by the control device 32 according to the temperature measurement value by the thermometer 61. When the ammonia mixed fuel is discharged from the mixing sealed container 16 and filled into the storage sealed container 50, regardless of the type of the combustion improver contained, the entire filled ammonia mixed fuel is in a uniform and homogeneous solution state or a uniform emulsion state (not separated into upper and lower layers). By maintaining the temperature inside the storage sealed container 50 equal to the liquid-phase temperature inside the mixing sealed container 16, the above-described uniform and homogeneous solution state or uniform emulsion state can be maintained. Further, even when the above-described stirring and mixing and temperature adjustment are stopped for a certain period after filling the ammonia mixed fuel into the storage sealed container 50, if the temperature adjustment to the same temperature as at the time of stirring and mixing and filling is performed again before using the ammonia mixed fuel for combustion, it is possible to restore it to a uniform and homogeneous solution state or a uniform emulsion state.

[0102] Incidentally, even when discharging the ammonia mixed fuel from the storage sealed container 50, the composition change of the mixed fuel, which was described in the case of discharging from the mixing sealed container, occurs. In the storage sealed container 50 of the manufacturing apparatus 10 according to another embodiment, in order to suppress this composition change, as shown in FIG. 9, in addition to the configuration of the storage sealed container 50 of FIG. 8, a nitrogen gas injection line 64 having the same configuration as the nitrogen gas introduction line 30b shown in FIG. 4 described above, and a gas phase discharge line 59 for discharging the gas in the gas phase portion of the storage sealed container 50 to the upper part, preferably to the uppermost surface, of the storage sealed container 50 (a gas phase discharge valve 59a is provided in the gas phase discharge line 59) are provided. With the above configuration, it is possible to quickly discharge the ammonia mixed fuel while suppressing the change in the liquid phase composition due to the progress of evaporation of the mixture in the storage sealed container 50 accompanying the discharge of the ammonia mixed fuel described above. The nitrogen gas injection line 64 is led from a storage container (not shown), such as a general pressurized nitrogen gas cylinder, filled with an internal pressure of about 10 to 15 MPa. The nitrogen gas injection line 64 is provided with a pressure reducing valve 64a, a pressure gauge 64b, and a regulating valve 64c between its upstream side and the mixing sealed container 16. The nitrogen gas led by the nitrogen gas injection line 64 is depressurized by the pressure reducing valve 64a so that the indicated value of the pressure gauge 64b reaches a predetermined pressure (for example, the saturated vapor pressure + about 0.05 to 0.1 MPa) equal to or higher than the saturated vapor pressure of the mixture in the storage sealed container 50 (the indicated value of the pressure gauge 62). When the liquid phase of the mixture is discharged from the storage sealed container 50, the regulating valve 64c is opened in conjunction with the opening of the discharge valve 58, and the ammonia mixed fuel is discharged into the ammonia mixed fuel supply line 60 in a form that is forcibly pushed out by the nitrogen gas injected from the gas phase side. The operation of these series of valves is controlled by a control signal transmitted by the control device 32. As described above, when discharging the ammonia mixed fuel from the storage sealed container 50, similar to the case of discharging the ammonia mixed fuel from the mixing sealed container 16 shown in FIG. 4, nitrogen gas is pressurized and injected into the gas phase part in the storage sealed container 50, so that the composition change is substantially reduced and the discharge is rapid. When injecting the ammonia mixed fuel from the mixing sealed container 16 into the storage sealed container 50 again through the liquid phase discharge line 22, first open the gas phase discharge valve 59a, slightly open the liquid phase discharge valve 22a to introduce a small amount of ammonia mixed fuel into the storage sealed container 50, and after purging the gas (air, nitrogen, etc.) in the storage sealed container 50 with the volatile vapor, the gas phase discharge valve 59a is closed, so that the inside of the storage sealed container 50 is gas replaced.

[0103] In the manufacturing apparatus 10 according to another embodiment, the discharge port 54 is provided at the bottom surface of the storage sealed container 50, and a volumetric flow meter 65 configured to continuously measure the discharge volumetric flow rate of the ammonia mixed fuel discharged in the liquid phase from the discharge port 54 is provided at the discharge port 54. Further, when the ammonia mixed fuel is injected into the storage sealed container 50 through the injection port 52, the ammonia mixed fuel is injected until a predetermined full filling amount or a predetermined amount equal to or less than the full filling amount is reached, and when the ammonia mixed fuel is discharged from the storage sealed container 50 through the discharge port 54, an injection / discharge control mechanism is provided which is configured such that the internal volume of the storage sealed container 50 continuously decreases at a volume change rate substantially equal to the discharge volumetric flow rate measured by the volumetric flow meter 65 while maintaining the airtightness and internal pressure of the storage sealed container 50. When the composition change occurs during the discharge of the ammonia mixed fuel, as described above for the same situation in the mixing sealed container 16, with the discharge of the ammonia mixed fuel, the volume of the discharged liquid phase portion and the volume of the gas phase portion in the storage sealed container 50 increase, and the internal pressure decreases. As a result, evaporation (boiling) of the ammonia mixed fuel from the liquid phase to the gas phase occurs in the storage sealed container 50, and the composition of the vapor at that time is different from the liquid phase composition. Therefore, if the volume of the gas phase portion and the internal pressure are maintained so that the gas-liquid equilibrium state in the storage sealed container 50 is maintained even during the discharge of the liquid phase, the evaporation does not occur, and the composition of the discharged ammonia mixed fuel is also kept constant. Thus, as described above, when the ammonia mixed fuel is discharged from the storage sealed container 50, if the injection / discharge control mechanism is provided which continuously decreases the internal volume of the storage sealed container 50 at a volume change rate equal to the discharge volumetric flow rate measured by the volumetric flow meter 65 while maintaining the airtightness and internal pressure of the storage sealed container 50, the ammonia mixed fuel can be discharged while keeping the discharge composition constant.

[0104] FIG. 10 shows a manufacturing apparatus 10 of one embodiment in which an example of the injection / discharge control mechanism falling within the scope of the above-described embodiment is provided. The storage sealed container 50 includes a cylinder 66 formed of a body portion (e.g., cylindrical shape) having an upright outer cylinder shape and a constant internal cross-sectional area orthogonal to the axial direction of the outer cylinder, and a bottom plate provided with an injection port 52 and a discharge port 54 for sealing the lower end opening of the body portion, and a piston 67 capable of reciprocating in the vertical direction while maintaining airtightness within the cylinder 66, and a reciprocating drive device 68 configured to reciprocate the piston 67 in the vertical direction. Here, the injection / discharge control mechanism is configured to perform the following control. That is, when the ammonia mixed fuel is injected into the storage sealed container 50 through the injection port 52, the lower surface of the piston 67 is pushed up to the full filling position (hereinafter referred to as the H position) or a predetermined position below the full filling position within the cylinder 66 by the reciprocating drive device 68 and then stopped. At this time, it is preferable that the mixing sealed container 16 and the cylinder 66 are relatively arranged such that the H position is approximately the height of the gas-liquid interface of the ammonia mixed fuel in the mixing sealed container 16. In this state, the ammonia mixed fuel is stored in the cylinder 66. After filling the ammonia mixed fuel, when the ammonia mixed fuel is discharged from the storage sealed container 50 through the discharge port 54, the piston 67 is continuously pushed down by the reciprocating drive device 68 at a linear velocity substantially equal to a value calculated by dividing the discharge volume flow rate measured by the volume flow meter 65 by the internal cross-sectional area of the body portion of the cylinder 66 while resisting the saturated vapor pressure (equal to the internal pressure) of the ammonia mixed fuel in the storage sealed container 50 measured by the pressure gauge 62, and then its lower surface stops at the discharge end position (hereinafter referred to as the L position) near the bottom plate of the cylinder 66. At the time of this discharge, since the product of the internal cross-sectional area and the linear velocity is substantially equal to the discharge volume flow rate, the internal volume of the storage sealed container 50 can be continuously decreased at a volume change rate substantially equal to the discharge volume flow rate described above. As a result, the ammonia mixed fuel can be discharged while suppressing the composition change.

[0105] In the embodiment of FIG. 10, since the body and the bottom plate of the storage sealed container 50 become the cylinder 66 and its upper surface becomes the piston 67 that reciprocates, it is preferable that there are no obstacles inside the lower surface of the piston 67 and the cylinder 66 that prevent the reciprocating movement of the piston 67. For this reason, as shown in FIG. 11, the conduits (such as sheaths) of the thermometer 61 and the conduit of the pressure gauge 62 are installed on the inner surface of the lowermost part of the body of the cylinder 66 or the inner surface of the bottom surface so that the tip ends of the respective conduits are flush. At this time, the inner wall of the surrounding cylinder 66 is counterbored so that the thermometer measuring part at the tip of the conduit (such as a sheath) of the thermometer 61 comes into contact with the liquid. When it is necessary to improve the accuracy of the pressure gauge 62, it is preferable that the side part of the pressure gauge is extended so as to be located above the gas-liquid interface of the ammonia mixed fuel, and the influence of the liquid column pressure is eliminated. When the stirrer 63 is installed, a counterbore is provided downward on the bottom plate so that the operating part such as the stirring blade is located below the bottom surface of the cylinder 66, and it is installed therein, or a circulation pipe (not shown) that extracts the ammonia mixed fuel inside the cylinder 66 to the outside and then refluxes it inside again is provided, and a configuration in which the operating part of the stirrer 63 is arranged in the pipe is preferable. Furthermore, the injection port 52 and the discharge port 54 are preferably provided on the bottom surface of the cylinder 66 so as not to be blocked by the reciprocating movement of the piston 67. In the example of FIG. 10, the piston 67 is lifted and lowered (reciprocated) by a reciprocating drive device 68 including a motor 68a and a crank mechanism 68b with variable output and rotation speed. In the reciprocating drive device 68 of this example, the rotation of the motor 68a is decelerated by a reduction gear and then transmitted to the crank mechanism 68b, but it is not limited to this. Depending on the output characteristics of the motor 68a, the saturated vapor pressure of the ammonia mixed fuel (the measured value of the pressure gauge 62), the required variable range of the lifting and lowering (reciprocating) speed of the piston 67 accompanying injection and discharge, and the required accuracy of the lifting and lowering (reciprocating) stop position, etc., the reciprocating drive device 68 is appropriately designed. The piston 67 can move up and down (reciprocate) when the crank of the crank mechanism 68b rotates half a turn in the forward and reverse directions within the range from its upward position to its downward position. At this time, the H position and the L position of the piston 67 are set at the top dead center of the piston 67 or slightly below the top dead center, and at the bottom dead center or slightly above the bottom dead center, respectively. The H position and the L position are calibrated and recognized by a position sensor that detects the position of the piston 67 or the crank of the crank mechanism 68b, or an angle sensor that detects the rotation angle of the motor 68a (these are not shown in the figure). When the piston 67 reaches the H position to the L position, the power supply to the motor 68a is cut off, and preferably, the motor 68a is forced to stop by a brake mechanism (not shown). At the start of the injection of the ammonia mixed fuel, the piston 67 is at the L point. After the liquid phase discharge valve 22a is opened, the piston 67 rises at a linear velocity such that the measured value of the pressure gauge 62 remains substantially constant to a predetermined position at or below the H point. After the ammonia mixed fuel is injected and filled into the cylinder 66, the liquid phase discharge valve 22a is closed, and the ammonia mixed fuel is stored in that state. Then, when the discharge valve 58 is opened and the ammonia mixed fuel is discharged, the motor 68a is driven at a rotational speed such that the descending speed of the piston 67 near the center between the H point and the L point is substantially equal to the above-mentioned linear velocity obtained from the discharge flow rate value measured by the volume flow meter 65, and stops when the piston 67 reaches the L position. The above series of operations is controlled by a control signal from the control device 32. In addition, in this embodiment, the reciprocating drive device 68 is not necessarily limited to the above-described crank mechanism 68b. Alternatively, for example, a reciprocating drive device using a rack & pinion mechanism, a ball screw mechanism, or a feed screw mechanism can also be adopted.

[0106] In the manufacturing apparatus 10 including the storage sealed container 50 of another embodiment, when the ammonia mixed fuel is injected into the storage sealed container 50 through the injection port 52, the ammonia mixed fuel is injected until it reaches a predetermined full filling amount or a predetermined amount equal to or less than the full filling amount. After the injection of the ammonia mixed fuel into the storage sealed container 50, when the ammonia mixed fuel is discharged from the storage sealed container 50 through the discharge port 54, while maintaining the airtightness of the storage sealed container 50, at a pressure higher than the saturated vapor pressure of the ammonia mixed fuel at the temperature of the ammonia mixed fuel in the storage sealed container 50, it is provided with an injection / discharge control mechanism configured to extrude the ammonia mixed fuel from the storage sealed container 50. According to the above configuration, since the ammonia mixed fuel in the storage sealed container 50 is compressed at a pressure exceeding its saturated vapor pressure during the discharge process, the gas phase part disappears and the whole becomes a liquid state and is discharged from the discharge port 54. Therefore, since evaporation (boiling) does not occur during the discharge process, it can be discharged at a high pressure equal to or higher than the saturated vapor pressure without causing the above-described discharge composition change.

[0107] FIG. 11 shows a manufacturing apparatus 10 of an embodiment in which an example of the injection / discharge control mechanism falling within the scope of the above embodiment is provided. In the embodiment of FIG. 11, since it has substantially the same configuration as the above-described embodiment shown in FIG. 10 (for example, a reciprocating drive device 68 having a motor 68a and a crank mechanism 68b of a common operating mechanism, etc.), the corresponding component members are denoted by the same reference numerals as those in FIG. 10, and in the following, the description common to the manufacturing apparatus 10 of FIG. 10 is omitted. In the manufacturing apparatus 10 of FIG. 11, when injecting and filling the ammonia mixed fuel, the injection and filling are performed by the same operations as in the case of the manufacturing apparatus 10 of FIG. 10, and the ammonia mixed fuel is stored in that state. At the time of discharge, when the motor 68a gradually lowers the piston 67, after the initial value (= saturated vapor pressure) of the pressure gauge 62 before the start of the descent is maintained for a while, the internal pressure starts to rise when the gas phase in the cylinder 66 disappears. While further lowering the piston 67, when the measured value of the pressure gauge 62 reaches a predetermined pressure value that does not exceed the pressure resistance of the storage sealed container 50, the discharge valve 58 is opened at a predetermined opening degree, and the ammonia mixed fuel is discharged. During the discharge, if the opening degree of the discharge valve 58 and the descent speed of the piston 67 are adjusted so that the measured value of the pressure gauge 62 maintains the predetermined pressure, the discharge flow rate (measured by the volumetric flow meter 65) of the ammonia mixed fuel led to the ammonia mixed fuel supply line 60 through the discharge port 54 can be changed. The above series of operations is controlled by the control signal of the control device 32.

[0108] In the present embodiment, the constituent members such as the storage sealed container 50 (cylinder 66 and piston 67) and the pressure gauge 62 may be subject to rapid pressure fluctuations before and after the disappearance of the gas phase, and thus it is necessary to have a pressure resistance and structure that can withstand them. In addition to the configuration of the storage sealed container 50 of the present embodiment, it is also possible to provide the configuration of the mixing sealed container 16 provided with the continuous quantitative introduction mechanism of the raw material described in the embodiment of FIG. 5 above. In that case, it is preferable that the above H point and L point are adjusted to be the top dead center and bottom dead center of the piston 67, respectively, and the discharge valve 58 and the liquid phase discharge valve 22a are configured to be opened and closed at appropriate opening degrees in conjunction with the continuous lifting (reciprocating) of the piston 67 by the crank mechanism 68b that rotates at a constant speed. Thereby, while continuously manufacturing the ammonia mixed fuel by the mixing sealed container 16 of FIG. 5, it becomes possible to pressurize the storage sealed container 50 of the present embodiment to a pressure equal to or higher than the saturated vapor pressure and continuously discharge it. At this time, the storage sealed container 50 of the present embodiment functionally becomes equivalent to a so-called plunger pump. In addition, when the continuous quantitative introduction mechanism of the raw materials shown in FIG. 5 described above is not provided, in this embodiment as well, the reciprocating drive device 68 is not necessarily limited to the crank mechanism 68b described above. Alternatively, for example, a reciprocating drive device using a rack & pinion mechanism, a ball screw mechanism, or a feed screw mechanism may be employed. Also, in the above-described embodiment, in the discharge process, since there is no gas phase portion in the cylinder 66, not only the configuration in which the cylinder 66 is upright as shown in FIG. 11, but also, for example, a configuration in which it is laid down horizontally by 90 degrees, the above-described functions can be generally achieved.

[0109] Furthermore, in the storage sealed container 50 of the manufacturing apparatus 10 of one embodiment, as shown in FIG. 12, similar to the mixing state evaluation device described for the mixing sealed container 16, a mixing state evaluation device 6 configured to evaluate the mixing state of the ammonia mixed fuel 9 is preferably provided. FIG. 12 is a block diagram of an example of the main part of the manufacturing apparatus 10 of one embodiment. The mixing state evaluation device 6 9 Based on the evaluation result of the mixing state obtained by, the control device 32 generates a control signal for adjusting the intensity and time of stirring and mixing by the stirrer 63, and based on this, the stirrer 63 performs stirring. In particular, an ammonia mixed fuel in which liquid ammonia and hydrocarbon for raw materials are emulsified may be re-separated over time during storage in the storage sealed container 50. In this case, by re-stirring the ammonia mixed fuel by the stirrer 63, it is possible to return it to the emulsion state again before supplying the ammonia mixed fuel to a combustor or the like.

[0110] The connection mechanism 56 (see FIGS. 8 to 11) of the manufacturing apparatus 10 according to one embodiment is configured to be detachable from each other with respect to the connection between the introduction line for introducing the ammonia mixed fuel into the storage sealed container 50 and the injection port 52. The storage sealed container 50 is a container that can be mounted on a transport device (not shown) in any one of land, water, and airspace. For example, in the case of the form shown in FIG. 8, the introduction line connected to the storage sealed container 50 is the liquid phase discharge line 22 extending from the mixing sealed container 16. However, this introduction line may extend from another temporary storage container (not shown) that temporarily stores the ammonia mixed fuel manufactured by the manufacturing apparatus 10. The configuration of this temporary storage container will basically be the same as any of the configurations of the storage sealed containers described so far. The transport devices include, for example, on land, vehicles (small / large automobiles, motorcycles with engines, etc.) including tank lorries capable of transporting ammonia and ammonia mixed fuel, railway vehicles, etc., in water, merchant ships including ships for transporting liquefied ammonia, passenger ships, warships, various working ships, submarines, etc., and in airspace, helicopters, airplanes, airships, drones, etc. The storage sealed container 50 has a scale and structure that can be moved or transported. According to the above configuration, the storage sealed container 50 after being filled with the ammonia mixed fuel is detached by the detachable connection mechanism 56 and mounted on the transport device, or the storage sealed container 50 is installed in advance on the transport device, filled with the ammonia mixed fuel, and then detached by the detachable connection mechanism 56, so that the ammonia mixed fuel manufactured by the manufacturing apparatus 10 can be efficiently loaded and transported on the transport device.

[0111] (Ammonia Mixed Fuel Supply Device) FIGS. 13(a) and (b) are block diagrams for explaining an example of the configuration of an ammonia mixed fuel supply device 70 according to one embodiment. The supply device 70 (the range enclosed by the dashed line) shown in Fig. 13(a) includes at least the above-described ammonia-mixed fuel production device 10 and the ammonia-mixed fuel supply line 60. In Fig. 13(a), for simplicity of illustration, only the mixing sealed container 16 and the storage sealed container 50 are shown. The ammonia-mixed fuel supply line 60 supplies the ammonia-mixed fuel discharged from the discharge port 54 of the storage sealed container 50 to a combustor 100 configured to burn the ammonia-mixed fuel. The ammonia-mixed fuel stored in the storage sealed container 50 is transferred to the storage sealed container 50 through the liquid-phase discharge line 22 after being produced in the mixing sealed container 16. The supply device 70 (the range enclosed by the dashed line) shown in Fig. 13(b) also includes at least the above-described ammonia-mixed fuel production device 10 and the ammonia-mixed fuel supply line 60. The form shown in Fig. 13(b) includes the mixing sealed container 16 as the production device 10 but does not include the storage sealed container 50. A part of the ammonia-mixed fuel supply line 60 becomes the liquid-phase discharge line 22 of the mixing sealed container 16. That is, the ammonia-mixed fuel discharged from the mixing sealed container 16 is supplied to a combustor 100 configured to burn the ammonia-mixed fuel through the ammonia-mixed fuel supply line 60 without passing through the storage sealed container 50.

[0112] In Figs. 13(a) and (b), an ammonia-mixed fuel supply machine 80 is provided on the ammonia-mixed fuel supply line 60. The ammonia-mixed fuel supply machine 80 is configured to supply the ammonia-mixed fuel to the combustor 100 at a predetermined flow rate and a predetermined discharge pressure. The ammonia-mixed fuel supply machine 80 includes, for example, a pressurizer or a liquid delivery pump (which may be, for example, the storage sealed container 50 shown in Fig. 11 above) that pressurizes the ammonia-mixed fuel to the pressure required by the combustor 100 and controls the flow rate for supply as needed, and an injector that discharges the ammonia-mixed fuel into the combustor 100. These are not shown. The combustor 100 is, for example, a direct-injection type combustor that supplies a liquid ammonia mixed fuel directly to the combustion chamber. A predetermined amount of air, oxygen-enriched air, oxygen gas, etc., required for combustion is separately introduced into the combustor through a separately provided introduction line (not shown). The ammonia mixed fuel vaporizes in the combustor 100 and then comes into contact with and diffuses and mixes with the air, oxygen-enriched air, oxygen gas, etc., and burns. Further, the combustor may be a combustor that pre-vaporizes the liquid ammonia mixed fuel by a pre-vaporizer (not shown) and supplies the gas. In this case, air, oxygen-enriched air, or oxygen may be pre-mixed with the vaporized ammonia mixed fuel at a predetermined ratio. When the ammonia mixed fuel supply machine 80 vaporizes the ammonia mixed fuel and supplies the gas, the ammonia mixed fuel supply machine 80 may include the above pre-vaporizer. In the above combustor, as necessary, a spark plug for igniting the vaporized gas of the ammonia mixed fuel, or auxiliary equipment such as an auxiliary burner for heating the vaporized gas of the ammonia mixed fuel to a temperature above its ignition temperature is appropriately provided so that combustion proceeds smoothly. These are not shown. With the supply device 70 configured as described above, the ammonia mixed fuel can be supplied to the combustor 100 at a predetermined discharge pressure.

[0113] The ammonia mixed fuel supply line 60, the combustor 100, a combustion gas discharge line (not shown) that discharges exhaust gas from the combustor 100 to the outside air, and the constituent materials around them are limited to materials having corrosion resistance against ammonia. In addition, in a part where a gas containing vaporized ammonia gas comes into contact and is heated to approximately 400 °C or higher by combustion heat or the like, for example, around an injector of the ammonia mixed fuel that discharges the ammonia mixed fuel into the combustor 100, a high-temperature gas contact part that comes into contact with the combustion gas inside the combustor 100, and a high-temperature part in the combustion gas line, although it depends on the concentration of ammonia, it is preferable to have resistance to high-temperature corrosion due to nitriding embrittlement based on nitrogen in ammonia. Particularly, in a location where a high-concentration ammonia gas comes into contact and is at 400 °C or higher, the corrosion resistance of chromium steel-based alloys such as iron, steel, cast iron, or stainless steel may be insufficient. Therefore, for these parts, as the material, it may be necessary to use metals with high corrosion resistance such as pure nickel, or Inconel (trademark), Hastelloy (trademark), Nimonic (trademark), etc. that contain nickel at a high content rate.

[0114] FIG. 14 is a block diagram showing an example of the configuration of the supply device 70 according to an embodiment. In the ammonia mixed fuel supply line 60 of the supply device 70 (the range surrounded by the broken line) shown in FIG. 14, a branch portion 110 for branching the ammonia mixed fuel in a predetermined quantity ratio is provided on the way to the combustor 100. The supply device 70 includes an ammonia mixed fuel reflux line 112. The ammonia mixed fuel reflux line 112 is configured to reflux the portion of the ammonia mixed fuel flowing through the ammonia mixed fuel supply line 60 that is branched without being supplied to the combustor 100 into the mixing sealed container 16 or the storage sealed container 50. As shown in FIG. 14, in the branch portion 110 constituted by a branch valve (not shown), a part of the ammonia mixed fuel supplied by the ammonia mixed fuel supply machine 80 at a predetermined flow rate and a predetermined discharge pressure required by the combustor 100 is branched and refluxed into the mixing sealed container 16 or the storage sealed container 50. Therefore, it is preferable that a pressure adjustment mechanism (not shown) for adjusting the branched ammonia mixed fuel to the same pressure condition as the ammonia mixed fuel in the mixing sealed container 16 or the storage sealed container 50 is provided in the ammonia mixed fuel reflux line 112. As this pressure adjustment mechanism, for example, a circulation pump or the like that can adjust the discharge pressure to be equal to the pressure in the mixing sealed container 16 or the storage sealed container 50 can be used. During the above-mentioned branching and refluxing, the control device 32 calculates the required amount of the ammonia mixed fuel used for combustion in the combustor 100 according to the required output of combustion in the combustor 100, and for this required amount, among the ammonia mixed fuel supplied from the supply machine 80, the surplus amount is branched at the branch portion 110 and refluxed into the mixing sealed container 16 or the storage sealed container 50 through the ammonia mixed fuel reflux line 112. A control signal is transmitted to the branch valve of the branch portion 110 and the pressure adjustment mechanism provided in the ammonia mixed fuel reflux line 112. Based on these control signals, the opening degree of the branch valve of the branch portion 110 and the pressure adjustment mechanism are controlled. Also, for the stable operation of the above control, a flow rate adjustment valve (not shown) may be provided in the ammonia mixed fuel reflux line 112, and the opening degree of this flow rate adjustment valve is also appropriately controlled by the control signal of the control device 32 in the same manner. According to the supply device 70 configured as described above, an ammonia mixed fuel in a required amount can be continuously supplied to the combustor 100 at a stable predetermined discharge pressure.

[0115] (Combustion device for ammonia mixed fuel) FIG. 15 is a block diagram for explaining an example of the configuration of a combustion device 120 for an ammonia mixed fuel according to an embodiment. In the present embodiment, the combustion device 120 is a device that generates thermal energy by burning the produced ammonia mixed fuel, or converts the thermal energy generated by combustion into other energy such as mechanical energy or electrical energy, and discharges the combustion gas into the atmosphere. Each obtained energy can be used for various applications described later. The combustion device 120 includes a supply device 70 (see FIG. 9) for the ammonia mixed fuel, a combustor 100, and a combustion gas discharge line 130. The combustor 100 is configured to burn the above-described ammonia mixed fuel. The supply device 70 is configured to supply the ammonia mixed fuel to the combustor 100 as described above. The combustion gas discharge line 130 is configured to discharge the combustion gas generated by the combustion of the ammonia mixed fuel in the combustor 100 into the atmosphere.

[0116] Furthermore, the combustion device 120 according to an embodiment optionally includes a selective catalytic reactor 128. As shown in FIG. 15, when the combustion device 120 includes the selective catalytic reactor 128, a nitrogen oxide, an ammonia concentration measuring device 122, a supply amount calculating device 124, and a metering supply device 126 are provided in association with the selective catalytic reactor 128.

[0117] In this combustion device 120, as shown in FIG. 15, it is preferable that the selective catalytic reactor 128 is provided on the exhaust side of the combustion gas of the combustor 100, that is, on the combustion gas discharge line 130. The selective catalytic reactor 128 is a reactor configured to decompose nitrogen oxides (including nitrogen monoxide, nitrogen dioxide, etc., which are air pollutants. Hereinafter, these may be collectively referred to as NOx) in the combustion gas discharged from the combustor 100 by catalytic reduction. That is, the selective catalytic reactor 128 reductively decomposes NOx that is by-produced when the ammonia-mixed fuel burns in the combustor 100 and is discharged from the combustion chamber of the combustor 100 and passes through the combustion gas discharge line 130 while being contained in the combustion gas.

[0118] Ammonia is known as a NOx reducing agent that selectively reductively decomposes NOx with high efficiency in the presence of an appropriate catalyst and is widely used. In the selective catalytic reactor 128, as the NOx reducing agent, ammonia that remains unburned in the combustion gas and is discharged after burning in the combustor 100, or in addition to that, ammonia separately supplied from the above-mentioned airtight container 12 for storing ammonia, and ammonia-mixed fuel separately supplied from the above-mentioned airtight container 50 for storage, either one can be used. FIG. 15 shows an embodiment in which any one of the ammonia that remains unburned in the combustion gas and is discharged after burning in the combustor 100, the ammonia separately supplied from the above-mentioned airtight container 12 for storing ammonia, and the ammonia-mixed fuel separately supplied from the above-mentioned airtight container 50 for storage is used together as a reducing agent. In this case, it is preferable that a selective catalytic reaction supply line 132 is provided that is configured to merge a predetermined amount of either the liquid ammonia or the ammonia-mixed fuel into the combustion gas discharge line 130. That is, the selective catalytic reaction supply line 132 is led from either the airtight container 12 for storing liquid ammonia or the airtight container 50 for storing the ammonia-mixed fuel.

[0119] In the embodiment of FIG. 15, in addition to the residual ammonia in the combustion gas discharged from the combustor 100, either the liquid ammonia or the ammonia in the ammonia mixed fuel is supplied to the selective catalytic reactor 128, whereby the NOx coexisting in the combustion gas can be surely reduced and decomposed. These are vaporized by the exhaust heat of the combustion gas at the confluence part 130a of the combustion gas and either one of the ammonia, and supplied to the selective catalytic reactor 128, and act as a reducing agent in the selective catalytic decomposition of NOx. In particular, when the ammonia mixed fuel is supplied for catalytic reduction, the coexisting hydrocarbon for raw material or alcohol for raw material also acts as a reducing agent in the selective catalytic reactor 128. Therefore, due to the synergistic effect of the reducing powers of ammonia and the hydrocarbon for raw material or alcohol for raw material, nitrogen oxides NOx can be decomposed more efficiently. Further, the catalyst in the selective catalytic reactor 128 is preferably maintained at a predetermined temperature such that the above selective catalytic reduction proceeds efficiently. For this purpose, the selective catalytic reactor 128 is provided at a position in the combustion gas discharge line 130 where the temperature of the combustion gas passing through the combustion gas discharge line 130 substantially coincides with the above predetermined temperature, or a temperature regulator (not shown) for adjusting the temperature of the catalyst inside the selective catalytic reactor 128 is provided, whereby the temperature inside the selective catalytic reactor 128 is preferably adjusted appropriately. For example, when the liquid ammonia in the airtight container 12 for ammonia storage is used as the reducing agent, as the catalyst, a honeycomb body made of a mixed oxide of vanadium - tungsten (or molybdenum) - titanium is preferably used, and the temperature of the catalyst suitable for the selective catalytic reduction at that time is approximately 300 to 470 °C. As the temperature regulator for maintaining the catalyst temperature in such a temperature range, for example, an electric heater is used.

[0120] Either liquid ammonia or ammonia mixed fuel in a predetermined amount is merged into the combustion gas discharge line 130 and used as a reducing agent for nitrogen oxides NOx in the selective catalytic reactor 128. Therefore, as shown in FIG. 15, the combustion device 120 preferably includes a nitrogen oxide-ammonia concentration measuring device 122, a supply amount calculation device 124, and a metering supply device 126. The nitrogen oxide-ammonia concentration measuring device 122 is provided in the combustion gas discharge line 130 on the combustion chamber side of the combustor 100 with respect to the confluence portion 130a of the selective catalytic reaction supply line 132 and the combustion gas discharge line 130, and is configured to measure the concentration of nitrogen oxides and the concentration of ammonia on the combustion chamber side with respect to the confluence portion 130a. As the nitrogen oxide-ammonia concentration measuring device 122, a known measuring device can be used.

[0121] The supply amount calculation device 124 is configured to calculate the amount of ammonia or ammonia mixed fuel to be supplied through the selective catalytic reaction supply line 132 based on the measurement results measured by the nitrogen oxide-ammonia concentration measuring device 122. The supply amount calculation device 124 includes, for example, a reference table in which the relationship between the measured concentration and the amount of ammonia or ammonia mixed fuel is determined in advance, and refers to the reference table from the measurement results measured by the nitrogen oxide-ammonia concentration measuring device 122 to calculate the amount of ammonia or ammonia mixed fuel to be supplied through the selective catalytic reaction supply line 132. The metering supply device 126 is provided in the selective catalytic reaction supply line 132 and is configured to control the supply amount of ammonia or ammonia mixed fuel based on the calculation result of the amount by the supply amount calculation device 124. The control of the supply amount of ammonia or ammonia mixed fuel is performed by adjusting the opening degree of an adjustment valve (not shown) provided in the selective catalytic reaction supply line 132 or the liquid supply output of a liquid supply mechanism (not shown) such as a liquid supply pump provided in the metering supply device 126. Thereby, even if the concentration of nitrogen oxides or ammonia in the combustion gas fluctuates, the amount of the reducing agent can be adjusted to an appropriate amount according to this fluctuation. NOx in the combustion gas can be surely removed by the catalytic reduction with ammonia supply described above. However, when it is necessary to further confirm the concentrations of the still remaining NOx and residual ammonia in the combustion gas discharged from the selective catalytic reactor 128 and released into the atmosphere, in addition to the configuration shown in FIG. 15, another set of nitrogen oxide / ammonia concentration measuring devices (not shown) having the same configuration as the nitrogen oxide / ammonia concentration measuring device 122 is preferably attached to the combustion gas discharge line 130 at the downstream of the selective catalytic reactor 128.

[0122] The combustor 100 may be, for example, an internal combustion engine such as a gas turbine, a jet engine, a reciprocating engine, or a rotary engine configured to extract mechanical power by utilizing the thermal energy of the combustion gas generated by the combustion of the ammonia mixed fuel. Further, the combustion device 120 may include an external combustion engine such as a steam turbine (including a boiler) or a Stirling engine configured to extract mechanical power by utilizing the thermal energy of the combustion gas generated by the combustion of the ammonia mixed fuel. In this case, there are a case where the external combustion engine and the combustor 100 are close to each other and can be regarded as substantially the same, and a case where they are separated and are separate bodies. In the case of separated separate bodies, a combustion gas transfer line (not shown) connecting between the combustor 100 and the external combustion engine is provided. The combustion gas discharge line 130 for the combustion gas discharged into the atmosphere when used in the external combustion engine is provided at the downstream of the external combustion engine. Furthermore, the combustor 100 may include a heat processing device (not shown) configured to perform heat processing by using the thermal energy of the combustion gas generated by the combustion of the ammonia mixed fuel. The heat processing device is a device that performs, for example, calcination, roasting, melting, fusing, welding, brazing, casting, annealing, iron bending, heat reduction, incineration, etc. of materials such as metals, ceramics, and resins by the thermal energy of the combustion gas. In this case, similar to the external combustion engine, there are a case where the heat processing device and the combustor 100 are close to each other and can be regarded as substantially the same, and a case where they are separated and are separate bodies. In the case of separated separate bodies, a combustion gas transfer line (not shown) connecting between the combustor 100 and the heat processing device is provided. The combustion gas discharge line for the combustion gas discharged into the atmosphere when used in the heat processing device is provided at the downstream of the heat processing device.

[0123] (Application of Other Ammonia Mixed Fuels) The combustion of ammonia mixed fuel can be used in the propulsion engines of power generation equipment and transportation equipment. The power generation equipment is, for example, power generation equipment that generates electricity in any one of land, water, and airspace. In this case, at least one of the above-described internal combustion engine and the above-described external combustion engine is mounted as the combustor 100 of the ammonia mixed fuel in the power generation equipment. The generator of the power generation equipment is configured to generate electricity using the mechanical power extracted by utilizing the thermal energy of the combustion gas of the ammonia mixed fuel, and the power output terminal of the power generation equipment is configured to output the power generated by the generator. In this case, the power generation equipment includes a control mechanism configured to control the amount of electric power at the power output terminal.

[0124] The transportation equipment is equipment configured to move or transport materials in any one of land, water, and airspace, and its propulsion engine is a power engine configured to generate a thrust for moving the transportation equipment. In this case, at least one of a combustion device of ammonia mixed fuel equipped with an internal combustion engine and a combustion device of ammonia mixed fuel equipped with an external combustion engine is mounted as the propulsion engine in the transportation equipment. Further, the transportation equipment includes a power conversion transmission mechanism configured to utilize, as at least a part of the thrust of the transportation equipment, the mechanical power extracted by at least one of the internal combustion engine and the external combustion engine from the thermal energy of the combustion gas of the ammonia mixed fuel. As transportation equipment, for example, on land, vehicles including tank lorries that can transport ammonia and ammonia mixed fuels (small and large automobiles, motorcycles with engines, etc.), railway vehicles, etc.; in water areas, merchant ships, passenger ships, warships, various working ships, etc. including ships for transporting liquefied ammonia, submarines, etc.; and in the airspace, helicopters, airplanes, airships, drones, etc. can be mentioned. In this case, the power conversion transmission mechanism is a known series of mechanisms for appropriately changing the direction, torque, or speed of power for use in propulsion drive and transmitting it to the final drive unit. For example, it includes cams, cranks, various gears, chains, belts, gearboxes, drive shafts, drive wheels, propellers or screws, etc. In addition to the above-described internal combustion engines and external combustion engines, there are power sources that can supply power. When these powers are combined to propel and drive the transportation equipment, the power conversion transmission mechanism includes, in addition to the series of mechanisms for transmitting to the drive unit, a synchronization mechanism for the powers of both and a resultant force mechanism such as coaxial drive.

[0125] Also, the transportation equipment may be equipped with the above-described power generation equipment. In this case, the transportation equipment is preferably configured to use at least a part of the required power in at least one of propulsion of the transportation equipment, operation control of the transportation equipment, and maintenance management of the transportation equipment, by using the thermal energy of the combustion gas of the ammonia mixed fuel to generate electric power output by the power generation equipment, and is provided with at least one of an electric propulsion mechanism and a power supply mechanism. In this case, the transportation equipment may be provided with at least one of a combustion device for ammonia mixed fuel equipped with an internal combustion engine and a combustion device for the ammonia mixed fuel equipped with an external combustion engine. In this case, it is provided with a power conversion transmission mechanism configured to convert at least a part of the mechanical power extracted by at least one of the internal combustion engine and the external combustion engine from the energy of the combustion gas of the ammonia mixed fuel into the power for propulsion of the transportation equipment.

[0126] By efficiently burning ammonia using such an ammonia mixed fuel in this way, it can be suitably used for internal combustion engines, external combustion engines, heating and processing appliances, and power generation equipment that can meet GHG emission regulations.

[0127] As described above, the ammonia mixed fuel, the manufacturing apparatus of the ammonia mixed fuel, the manufacturing method of the ammonia mixed fuel, the supply apparatus of the ammonia mixed fuel, the combustion apparatus of the ammonia mixed fuel, the power generation facility using the ammonia mixed fuel, and the transportation equipment using the ammonia mixed fuel have been described in detail. However, the present invention is not limited to the above-described embodiments and the following examples, and various improvements and modifications can of course be made without departing from the gist of the present invention.

[0128] (Example 1) Using the ammonia mixed fuel manufacturing apparatus shown in FIG. 2, liquefied ammonia [NH3] and liquefied propane [C3H8] were introduced into a sealed mixing container (internal volume: about 2 L) whose temperature was adjusted to about 5° C. in this order at a charging mass ratio of about 75:25 (total mass: about 490 g). (Prior to these introductions, the inside of the sealed mixing container 16 was sequentially gas-substituted with nitrogen gas and then with the volatile vapor of liquefied ammonia.) After the introduction of liquefied ammonia and liquefied propane was completed, all valves were closed, and while adjusting the liquid phase temperature to about 20° C., the mixture was stirred and mixed with a stirrer having a single stirring blade. Soon, the liquid phase was stably separated into two phases: an upper layer mainly composed of propane and a lower layer mainly composed of ammonia. At this time, the volume ratio of the upper layer to the lower layer was approximately 15:85 (total volume: about 810 cm 3 ), and the internal pressure (saturation vapor pressure) was about 1.6 MPa. At this time, while maintaining the airtightness, a capillary was inserted into the upper layer and the lower layer using the gas phase discharge line 21 (not shown), and about 0.5 cm 3 each was sampled from the upper layer and the lower layer, and the ammonia concentrations of the upper layer and the lower layer were measured by gas chromatography. As a result, they were about 16% by mass and about 87% by mass, respectively (the average ammonia concentration in the liquid phase of the entire upper and lower layers was about 77% by mass). Thereafter, while continuing stirring, when the liquid phase temperature was raised, the two-liquid phase interface of the upper and lower layers rose, and at about 23°C, the upper layer disappeared, and an ammonia mixed fuel that was uniformly dissolved as a whole was obtained. At this time, the internal pressure (saturated vapor pressure) of the mixing sealed container was about 1.7 MPa. Even when the liquid phase temperature was raised further, the liquid phase maintained a uniform state. However, thereafter, when the liquid phase temperature was lowered to less than about 23°C, it separated into two phases again. Also, even after holding for about 1 day while maintaining the liquid phase temperature at about 23°C, the liquid phase did not separate, and the internal pressure was also maintained at about 1.7 MPa.

[0129] (Example 2) Using the same mixed fuel production apparatus as in Example 1, liquefied ammonia and liquefied n-butane [n-C4H 10 were first introduced into the inside of a mixing sealed container (internal volume of about 2 L) whose temperature was adjusted to about 5°C from liquefied n-butane at a charging mass ratio of about 85:15 (total mass of about 570 g). Prior to these introductions, the inside of the mixing sealed container 16 was sequentially gas-displaced first with nitrogen gas and then with the volatile vapor of liquefied n-butane. After the introduction of liquefied ammonia and liquefied n-butane was completed, all valves were closed, and while adjusting the liquid phase temperature to about 20°C, it was stirred and mixed with a stirrer having a single-type stirring blade. Before long, the liquid phase stably separated into two phases: an upper layer mainly composed of n-butane and a lower layer mainly composed of ammonia. At this time, the volume ratio of the upper layer to the lower layer was approximately 7:93 (total volume of about 940 cm 3 ), and the internal pressure (saturated vapor pressure) was about 1.0 MPa. Thereafter, while continuing stirring, when the liquid phase temperature was raised, the two-liquid phase interface of the upper and lower layers rose, and at about 32°C, the upper layer disappeared, and an ammonia mixed fuel that was uniformly dissolved as a whole was obtained. At this time, the internal pressure (saturated vapor pressure) of the mixing sealed container was about 1.4 MPa. Even when the liquid phase temperature was raised further, the liquid phase maintained a uniform state. However, thereafter, when the liquid phase temperature was lowered to less than about 32°C, it separated into two phases again. Also, even after holding for about 10 hours while maintaining the liquid phase temperature at about 32°C, the liquid phase did not separate, and the internal pressure was also maintained at about 1.4 MPa.

[0130] (Example 3) Using the same ammonia mixed fuel production apparatus as in Example 1, first, as a mixed surfactant, a nonionic primary amine having a long-chain alkyl group derived from coconut oil and a primary amino group [-NH2] in the molecule, namely long-chain alkylamine [structural formula: C k H 2k+1 NH2, k ≒ 8 - 18], and an ionic quaternary ammonium chloride having a long-chain alkyl chain with 12 carbon atoms and a quaternary trimethylammonium group as chloride [structural formula: C 12 H 25 N + (CH3)3·Cl - were introduced into a sealed mixing container in a molar ratio of approximately 80:20 so that the concentration in the produced ammonia mixed fuel would be 1% by mass (introduction amount 5.76 g). Then, in exactly the same manner as in Example 2, liquefied n-butane and liquefied ammonia were introduced into the sealed mixing container (internal volume approximately 2 L) whose temperature was adjusted to approximately 5°C at a charged mass ratio of approximately 85:15 (total mass approximately 570 g). The pre-gas replacement was also carried out in the same manner as in Example 2. After the introduction was completed, while adjusting the liquid phase temperature to approximately 20°C, it was stirred and mixed for about 30 minutes with a stirrer having a single-type stirring blade. As a result, it was separated into two phases: ...

Claims

1. An ammonia mixed fuel, comprising: liquefied ammonia; and an auxiliary fuel for assisting the combustion of the ammonia, wherein the auxiliary fuel is (a) liquefied petroleum gas, naphtha, gasoline, kerosene, and light oil, and (b) a hydrocarbon for raw materials which is at least one hydrocarbon species contained as a component in any one of the liquefied petroleum gas, the naphtha, the gasoline, the kerosene, and the light oil, and is at least one of the above; wherein the content of the ammonia is 20 to 99% by mass, and the ammonia mixed fuel is in a vapor-liquid equilibrium state, and the entire liquid phase portion of the ammonia mixed fuel is maintained at a predetermined temperature according to the liquid phase composition such that the ammonia and the auxiliary fuel are in a solution state in which they are mutually dissolved or an emulsion state of the ammonia and the auxiliary fuel. The ammonia mixed fuel is characterized by this.

2. The ammonia mixed fuel according to claim 1, wherein the ammonia mixed fuel is stored in isolation within a sealed environment in which the vapor-liquid equilibrium is maintained.

3. An ammonia mixed fuel, comprising: liquefied ammonia; and an auxiliary fuel for assisting the combustion of the ammonia, wherein the auxiliary fuel is (a) liquefied petroleum gas, naphtha, gasoline, kerosene, and light oil, (b) a hydrocarbon for raw materials which is at least one hydrocarbon species contained as a component in any one of the liquefied petroleum gas, the naphtha, the gasoline, the kerosene, and the light oil, and (c) an alcohol for raw materials which is an alcohol having 3 or less carbon atoms, and is at least one of the above; The ammonia mixed fuel is in a gas-liquid equilibrium state, and at least a part of the liquid phase portion of the ammonia mixed fuel is in a solution state in which the ammonia and the combustion aid are dissolved in each other, or in an emulsion state of the ammonia and the combustion aid. The ammonia mixed fuel further contains 0.1 to 10% by mass of a surfactant, and is an ammonia mixed fuel.

4. The surfactant contains at least one nonionic surfactant and at least one ionic surfactant, and is the ammonia mixed fuel according to claim 3.

5. The surfactant is (A) In the molecular structure, a primary or secondary amino group [-NH ２ , or >NH], a polyoxyalkylene amino group [>N(C ａ H ２ａ O) ｃ -H, or -N((C ｂ H ２ｂ O) ｄ -H)((C ｂ H ２ｂ O) ｅ -H)] (a and b are 2 or 3, c is an integer from 1 to 8, d and e are 0 or positive integers such that d + e = 1 to 8), an amide group [-C(=O)NH ２ , a polyoxyalkylene amide group [-C(=O)N((C ｆ H ２ｆ O) ｇ -H)((C ｆ H ２ｆ O) ｈ -H)] (f is 2 or 3, g and h are 0 or positive integers such that g + h = 1 to 8), and a polyoxyalkylene group [-O(C ｉ H ２ｉ O) ｊ -H] (i is 2 or 3, j is an integer from 1 to 8), and has at least one group as a nonionic polar site. And an alkyl group [C ｋ H ２ｋ＋１ -] (k is an integer from 7 to 18), and an alkenyl group [C ｌ H ２ｌ－１-](where l is an integer from 7 to 18) having at least one group as a non-polar part, at least one of the non-ionic surfactants, (B) In the molecular structure, a quaternary methylammonium group, a quaternary methylalkanolammonium group, or a quaternary alkanolammonium group [-N ＋ (CH ３ ) ｐ (C ｍ H ２ｍ OH) ｑ ·X － , or >N ＋ (CH ３ ) ｒ (C ｎ H ２ｎ OH) ｓ ·X' － (where m and n are 2 or 3, p and q are 0 or positive integers such that p + q = 3, r and s are 0 or positive integers such that r + s = 2, and X and X' are any of Cl, Br, and I), and a carboxyl group [-C(=O)OH], having at least one group as an ionic polar part, and having at least one group as a non-polar part, at least one of the alkyl group [C ｔ H ２ｔ＋１ -](where t is an integer from 7 to 18) and the alkenyl group [C ｕ H ２ｕ－１ -](where u is an integer from 7 to 18), at least one of the ionic surfactants, the ammonia mixed fuel according to claim 4.

6. A manufacturing apparatus for manufacturing an ammonia mixed fuel, An airtight container for storing ammonia in a liquefied state, (a) liquefied petroleum gas, naphtha, gasoline, kerosene, and gas oil, (b) a hydrocarbon for raw materials which is at least one hydrocarbon species contained as a component in any one of the liquefied petroleum gas, the naphtha, the gasoline, the kerosene, and the gas oil, and (c) an alcohol for raw materials which is an alcohol having 3 or less carbon atoms, a closed container for storing a combustion aid for assisting the combustion of the ammonia, which is at least any one of them, A mixing closed container configured such that a solution state in which the ammonia and the combustion aid are dissolved or an emulsified mixture is obtained by stirring and mixing the ammonia and the combustion aid with a stirrer, and the mixture obtained by the stirring and mixing with the stirrer can maintain a gas-liquid equilibrium state, An ammonia introduction line provided with an ammonia metering introduction mechanism configured to connect the ammonia storage closed container and the mixing closed container and introduce a predetermined amount of the ammonia into the mixing closed container, A combustion aid introduction line provided with a combustion aid metering introduction mechanism configured to connect the combustion aid storage closed container and the mixing closed container and introduce a predetermined amount of the combustion aid from the combustion aid storage closed container into the mixing closed container, At least one liquid phase discharge line configured to discharge the mixture obtained by the stirring and mixing of the stirrer in the mixing closed container as an ammonia mixed fuel from the mixing closed container, a manufacturing apparatus for an ammonia mixed fuel, characterized in that it comprises.

7. When the ammonia and the combustion aid are introduced into the mixing closed container and stirred and mixed by the stirrer, a temperature adjustment mechanism configured to adjust the temperature of the mixture so that the saturated vapor pressure of the mixture in the mixing closed container is within a temperature range not exceeding the set pressure resistance of the mixing closed container is provided, The manufacturing apparatus for an ammonia mixed fuel according to claim 6.

8. When ammonia and the combustion aid are introduced into the closed mixing container and stirred and mixed by the stirrer, the temperature adjustment mechanism is configured to adjust the temperature of the mixture within the closed mixing container such that the mixture maintains a vapor-liquid equilibrium state, and the entire liquid phase portion of the mixture is in a solution state in which ammonia and the combustion aid are dissolved in each other or an emulsion state of ammonia and the combustion aid according to the liquid phase composition of the mixture. The manufacturing apparatus for ammonia mixed fuel according to claim 7.

9. The ammonia mixed fuel contains at least one of the liquefied petroleum gas, the hydrocarbon for raw material, and the alcohol for raw material as the combustion aid. The hydrocarbon for raw material is at least one hydrocarbon species contained as a component in the liquefied petroleum gas. The alcohol for raw material is methanol. The closed container for storing the combustion aid stores at least one of the liquefied petroleum gas, the hydrocarbon for raw material, and the alcohol for raw material. The manufacturing apparatus for ammonia mixed fuel according to any one of claims 6 to 8.

10. When discharging the ammonia mixed fuel from the liquid phase discharge line, nitrogen gas can be introduced into the gas phase portion in the closed mixing container at a discharge pressure equal to or higher than the saturated vapor pressure of the mixture in the closed mixing container. The manufacturing apparatus for ammonia mixed fuel according to any one of claims 6 to 9, further comprising a nitrogen gas introduction line connected to the closed mixing container.

11. The liquid phase discharge line is provided with a discharge flow meter configured to continuously measure the discharge flow rate of the ammonia mixed fuel discharged through the liquid phase discharge line. The ammonia is continuously and quantitatively introduced into the mixing sealed container from the ammonia storage sealed container at a flow rate equal to the discharge flow rate of the ammonia discharged through the liquid phase discharge line, which is calculated from the discharge flow rate of the ammonia mixed fuel measured by the discharge flow meter and the liquid phase composition of the ammonia mixed fuel. In parallel, the combustion aid is continuously and quantitatively introduced into the mixing sealed container from the combustion aid storage sealed container at a flow rate equal to the discharge flow rate of the combustion aid discharged through the liquid phase discharge line, which is calculated from the discharge flow rate of the ammonia mixed fuel and the liquid phase composition of the ammonia mixed fuel. The ammonia metering introduction mechanism and the combustion aid metering introduction mechanism are respectively configured as described in any one of claims 6 to 9 for the ammonia mixed fuel production apparatus.

12. Furthermore, a surfactant storage container for storing a surfactant, a surfactant introduction line provided with a surfactant metering introduction mechanism configured to connect the surfactant storage container and the mixing sealed container and introduce a predetermined amount of the surfactant into the mixing sealed container, In the mixing sealed container, the surfactant is stirred and mixed with the ammonia and the combustion aid by the stirrer, and the liquid phase discharge line discharges the mixture containing the surfactant. The ammonia mixed fuel production apparatus according to any one of claims 6 to 10.

13. The ammonia metering introduction mechanism and the combustion aid metering introduction mechanism are the ammonia metering introduction mechanism and the combustion aid metering introduction mechanism described in claim 11, further comprising the discharge flow meter described in claim 11, The surfactant metering introduction mechanism is configured to continuously and quantitatively introduce the surfactant from the surfactant storage container into the mixing sealed container at a flow rate equal to the discharge flow rate of the surfactant discharged through the liquid phase discharge line, which is obtained by multiplying the concentration of the surfactant in the ammonia mixed fuel calculated from the respective amounts of the ammonia, the combustion aid, and the surfactant pre-introduced into the mixing sealed container, and the discharge flow rate of the ammonia mixed fuel measured by the discharge flow meter. The manufacturing apparatus for ammonia mixed fuel according to claim 12.

14. The surfactant contains at least one nonionic surfactant and at least one ionic surfactant. The manufacturing apparatus for ammonia mixed fuel according to claim 12 or 13.

15. The surfactant is (A) In the molecular structure, a primary or secondary amino group [-NH ２ , or >NH], a polyoxyalkylene amino group [>N(C ａ H ２ａ O) ｃ -H, or -N((C ｂ H ２ｂ O) ｄ -H)((C ｂ H ２ｂ O) ｅ -H)] (a and b are 2 or 3, c is an integer from 1 to 8, d and e are 0 or positive integers such that d + e = 1 to 8), an amide group [-C(=O)NH ２ , a polyoxyalkylene amide group [-C(=O)N((C ｆ H ２ｆ O) ｇ -H)((C ｆ H ２ｆ O) ｈ -H)] (f is 2 or 3, g and h are 0 or positive integers such that g + h = 1 to 8), and a polyoxyalkylene group [-O(C ｉ H ２ｉ O) ｊ -H] (i is 2 or 3, j is an integer from 1 to 8), and has at least one group as a nonionic polar site among them, and at least one of the nonionic surfactants having at least one group selected from an alkyl group [C ｋ H ２ｋ＋１ -] (k is an integer of 7 to 18) and an alkenyl group [C ｌ H ２ｌ－１ -] (l is an integer of 7 to 18) as a nonpolar part, (B) In the molecular structure, a quaternary methylammonium group, a quaternary methylalkanolammonium group, or a quaternary alkanolammonium group [-N ＋ (CH ３ ) ｐ (C ｍ H ２ｍ OH) ｑ ·X － , or >N ＋ (CH ３ ) ｒ (C ｎ H ２ｎ OH) ｓ ·X' － (m and n are 2 or 3, p and q are 0 or positive integers such that p + q = 3, r and s are 0 or positive integers such that r + s = 2, and X and X' are any of Cl, Br, and I), and at least one group selected from a carboxyl group [-C(=O)OH] as an ionic polar part, and at least one of the ionic surfactants having at least one group selected from an alkyl group [C ｔ H ２ｔ＋１ -] (t is an integer of 7 to 18) and an alkenyl group [C ｕ H ２ｕ－１ -] (u is an integer of 7 to 18) as a nonpolar part, The ammonia mixed fuel manufacturing apparatus according to claim 14.

16. The combustion aid is at least one of those described in the above (a) and (b), When the ammonia and the combustion improver are stirred and mixed in the airtight mixing container, the liquid phase portion of the mixture is separated into upper and lower two layers, and the entire layer of each of the liquid phase portions separated into the upper and lower two layers becomes a solution state or an emulsion state. The ammonia metering introduction mechanism and the combustion improver metering introduction mechanism are configured to introduce the ammonia and the combustion improver into the airtight mixing container at a predetermined quantitative ratio, and the temperature adjustment mechanism is configured to perform the stirring and mixing while maintaining a predetermined liquid phase temperature. The manufacturing apparatus for an ammonia mixed fuel according to claim 6 or 7, wherein at least one of the liquid phase portions of the upper and lower two layers is discharged from the airtight mixing container through one or two of the liquid phase discharge lines, thereby producing one or two ammonia mixed fuels in which the ammonia and the combustion improver are in a solution state or an emulsion state at one or two predetermined composition ratios.

17. The airtight mixing container is provided with a mixing state evaluation device configured to evaluate the mixing state of the mixture. The manufacturing apparatus for an ammonia mixed fuel according to any one of claims 6 to 16, further comprising a stirring adjustment device configured to adjust the intensity and time of the stirring and mixing by the stirrer according to the evaluation result of the mixing state evaluation device.

18. When introducing the ammonia and the combustion improver into the airtight mixing container, temperature adjustment devices configured to adjust the temperature of the ammonia and the temperature of the combustion improver are provided in the ammonia introduction line and the combustion improver introduction line respectively, so that the temperature of the ammonia passing through the ammonia introduction line and the temperature of the combustion improver passing through the combustion improver introduction line are equal to the temperature of the mixture inside the airtight mixing container. The manufacturing apparatus for an ammonia mixed fuel according to any one of claims 6 to 17.

19. When introducing the ammonia and the combustion aid into the sealed mixing container, a heating device for heating the ammonia in the sealed ammonia storage container and / or the combustion aid in the sealed combustion aid storage container is provided in the sealed ammonia storage container and / or the sealed combustion aid storage container. The manufacturing apparatus for ammonia mixed fuel according to any one of claims 6 to 18.

20. Further comprising a sealed storage container for ammonia mixed fuel configured to store the ammonia mixed fuel in a vapor-liquid equilibrium state. The sealed storage container includes an injection port into which the ammonia mixed fuel is injected, and a discharge port provided at a lower portion of the sealed storage container configured to discharge the ammonia mixed fuel to the outside. A connecting mechanism configured to inject the ammonia mixed fuel from the liquid phase discharge line into the sealed storage container while maintaining airtightness and internal pressure is provided at the injection port. The manufacturing apparatus for ammonia mixed fuel according to any one of claims 6 to 19.

21. A stirrer configured to stir and mix the ammonia mixed fuel is provided in the sealed storage container. The manufacturing apparatus for ammonia mixed fuel according to claim 20.

22. A mixing state evaluation device configured to evaluate the mixing state of the ammonia mixed fuel is provided in the sealed storage container. Based on the evaluation result of the mixing state obtained by the mixing state evaluation device, a stirring adjustment device for adjusting the intensity and time of stirring and mixing by the stirrer provided in the sealed storage container is provided. The manufacturing apparatus for ammonia mixed fuel according to claim 21.

23. The sealed storage container is provided with a temperature adjustment device configured to adjust the temperature of the ammonia mixed fuel inside the sealed storage container so that the internal pressure of the sealed storage container is within a temperature range that does not exceed the set pressure resistance of the sealed storage container. The manufacturing apparatus for ammonia mixed fuel according to claim 21 or 22.

24. When the ammonia mixed fuel in the storage sealed container is stirred and mixed by the stirrer, the entire liquid phase portion of the ammonia mixed fuel is in a solution state in which ammonia and the combustion aid are dissolved in each other or an emulsion state of ammonia and the combustion aid according to the liquid phase composition of the ammonia mixed fuel. The temperature adjusting device is configured to adjust the temperature of the ammonia mixed fuel so that it is in a temperature range, and the manufacturing apparatus for ammonia mixed fuel according to any one of claims 21 to 23.

25. When discharging the ammonia mixed fuel from the discharge port, nitrogen gas can be introduced into the gas phase portion in the storage sealed container at a discharge pressure equal to or higher than the saturated vapor pressure of the ammonia mixed fuel in the storage sealed container. The manufacturing apparatus for ammonia mixed fuel according to any one of claims 20 to 24, further comprising a nitrogen gas introduction line connected to the storage sealed container.

26. The storage sealed container is provided with the discharge port at the bottom surface of the storage sealed container. A volume flow meter configured to continuously measure the volume flow rate of the ammonia mixed fuel discharged in a liquid phase from the discharge port is provided at the discharge port. When the ammonia mixed fuel is injected into the storage sealed container through the injection port, the ammonia mixed fuel is injected until a predetermined amount equal to or less than the full filling amount of the storage sealed container is reached. After the injection of the ammonia mixed fuel into the storage sealed container, when the ammonia mixed fuel is discharged from the storage sealed container through the discharge port, the injection / discharge control mechanism is configured such that the internal volume of the storage sealed container continuously decreases at a volume change rate substantially equal to the discharge volume flow rate measured by the volume flow meter while maintaining the airtightness and internal pressure of the storage sealed container. The manufacturing apparatus for ammonia mixed fuel according to any one of claims 20 to 24, further comprising the injection / discharge control mechanism.

27. The storage sealed container It has an upright outer cylinder shape, a body portion with a constant internal cross-sectional area orthogonal to the axial direction of the outer cylinder shape, and a bottom plate that seals the lower end opening of the body portion and is provided with the injection port and the discharge port. A piston that can reciprocate in the vertical direction while maintaining airtightness within the cylinder. It is equipped with a reciprocating drive device configured to reciprocate the piston in the vertical direction. The injection / discharge control mechanism. When the ammonia mixed fuel is injected into the storage sealed container through the injection port, within the cylinder, after the piston is pushed up by the reciprocating drive device to a predetermined full filling position or a predetermined position below the full filling position, it stops. Further, when the ammonia mixed fuel is discharged from the storage sealed container through the discharge port after filling the ammonia mixed fuel, while resisting the saturated vapor pressure of the ammonia mixed fuel in the storage sealed container, the piston is continuously pushed down by the reciprocating drive device at a linear velocity substantially equal to the value calculated by dividing the discharge volume flow rate measured by the volume flow meter by the internal cross-sectional area of the body portion of the cylinder, and then stops near the bottom plate. The manufacturing apparatus for ammonia mixed fuel according to claim 26.

28. When the ammonia mixed fuel is injected into the storage sealed container through the injection port, it is configured such that the ammonia mixed fuel is injected until a predetermined amount below the full filling amount of the storage sealed container is reached. After injecting the ammonia mixed fuel into the storage sealed container, when the ammonia mixed fuel is discharged from the storage sealed container through the discharge port, while maintaining the airtightness of the storage sealed container, at a pressure higher than the saturated vapor pressure of the ammonia mixed fuel at the temperature of the ammonia mixed fuel in the storage sealed container, the manufacturing apparatus for ammonia mixed fuel according to any one of claims 20 to 24, further comprising an injection / discharge control mechanism configured to extrude the ammonia mixed fuel from the storage sealed container.

29. The storage sealed container has an outer cylinder shape, a barrel portion having a constant internal cross-sectional area orthogonal to the axial direction of the outer cylinder shape, and a bottom plate that seals the opening at one end of the barrel portion and is provided with the injection port and the discharge port, and a cylinder having the same; a piston that can reciprocate in the axial direction while maintaining airtightness within the cylinder; and a reciprocating drive device configured to reciprocate the piston in the axial direction, and is provided with the same; The injection / discharge control mechanism When the ammonia mixed fuel is injected into the storage sealed container through the injection port, in the cylinder, after the piston is pushed up by the reciprocating drive device to a predetermined full filling position or a predetermined position below the full filling position, it is configured to stop; After filling the ammonia mixed fuel, when the ammonia mixed fuel is discharged from the storage sealed container through the discharge port, while maintaining the airtightness of the storage sealed container, at a pressure exceeding the saturated vapor pressure of the ammonia mixed fuel in the storage sealed container, the piston is continuously pushed down by the reciprocating drive device and then configured to stop near the bottom plate. The manufacturing apparatus for ammonia mixed fuel according to claim 26.

30. The connection mechanism is configured to be detachable from each other with respect to the connection between the introduction line for introducing the ammonia mixed fuel into the storage sealed container and the injection port; The storage sealed container is mounted on a transportation device in any one of land, water, and airspace. The manufacturing apparatus for ammonia mixed fuel according to any one of claims 20 to 29.

31. The manufacturing apparatus for ammonia mixed fuel according to any one of claims 6 to 30; and an ammonia mixed fuel supply line for supplying the ammonia mixed fuel discharged from the liquid phase discharge line to a combustor configured to burn the ammonia mixed fuel. The supply apparatus for ammonia mixed fuel is characterized by comprising the same.

32. The manufacturing apparatus of the ammonia mixed fuel according to any one of Claims 19 to 30, and an ammonia mixed fuel supply line for supplying the ammonia mixed fuel discharged from the discharge port of the storage sealed container to a combustor configured to burn the ammonia mixed fuel. A supply apparatus for an ammonia mixed fuel, characterized by comprising:

33. The supply apparatus for an ammonia mixed fuel according to Claim 31 or 32, wherein an ammonia mixed fuel supply machine configured to supply the ammonia mixed fuel to the combustor at a predetermined flow rate and a predetermined discharge pressure is provided in the ammonia mixed fuel supply line.

34. A branch portion for branching the ammonia mixed fuel in a predetermined amount ratio is provided in the ammonia mixed fuel supply line on the way to the combustor, and an ammonia mixed fuel reflux line configured to reflux a portion of the ammonia mixed fuel flowing through the ammonia mixed fuel supply line that is branched without being supplied to the combustor into the mixing sealed container or the storage sealed container. The supply apparatus for an ammonia mixed fuel according to any one of Claims 31 to 33.

35. A combustor configured to burn the ammonia mixed fuel according to any one of Claims 1 to 5, the supply apparatus for the ammonia mixed fuel according to any one of Claims 31 to 34, and a combustion gas discharge line configured to discharge combustion gas generated by combustion of the ammonia mixed fuel in the combustor into the atmosphere. A combustion apparatus for an ammonia mixed fuel, characterized by comprising:

36. In the combustion gas discharge line, there is provided a selective catalytic reactor configured to decompose nitrogen oxides that are by-produced when the ammonia mixed fuel burns in the combustor, are contained in the combustion gas, are discharged from the combustion chamber of the combustor, and pass through the combustion gas discharge line, by catalytic reduction using the ammonia or the vaporized gas of the ammonia mixed fuel. The combustion apparatus for ammonia mixed fuel according to claim 35.

37. A selective catalytic reaction supply line configured to merge either a predetermined amount of either the ammonia or the ammonia mixed fuel into the combustion gas at a confluence provided in the combustion gas discharge line between the combustion chamber and the selective catalytic reactor, from either one of the sealed container for storing the ammonia and the sealed container for storing the ammonia mixed fuel. The combustion apparatus for ammonia mixed fuel according to claim 36.

38. A nitrogen oxide concentration measuring device and an ammonia concentration measuring device provided in the combustion gas discharge line on the combustion chamber side with respect to the confluence of the selective catalytic reaction supply line and the combustion gas discharge line, and configured to measure the concentration of nitrogen oxides and the concentration of ammonia on the combustion chamber side with respect to the confluence, respectively; A supply amount calculating device configured to calculate the amount of the ammonia or the ammonia mixed fuel to be supplied through the selective catalytic reaction supply line based on the concentration results measured by each of the nitrogen oxide concentration measuring device and the ammonia concentration measuring device; A metering supply device provided in the selective catalytic reaction supply line and configured to control the supply amount of the ammonia or the ammonia mixed fuel supplied through the selective catalytic reaction supply line based on the calculation result of the amount by the supply amount calculating device. The combustion apparatus for ammonia mixed fuel according to claim 37.

39. The combustor is used as an internal combustion engine configured to extract mechanical power by utilizing the energy of the combustion gas generated by the combustion of the ammonia mixed fuel, and is the combustion device for the ammonia mixed fuel according to any one of claims 35 to 38.

40. An external combustion engine configured to extract mechanical power by utilizing the energy of the combustion gas generated by the combustion of the ammonia mixed fuel, and a combustion gas transfer line configured to transfer the combustion gas from the combustor to the external combustion engine, and is the combustion device for the ammonia mixed fuel according to any one of claims 35 to 38.

41. A heat processing appliance configured to perform heat processing by using the energy of the combustion gas generated by the combustion of the ammonia mixed fuel, and a combustion gas transfer line configured to transfer the combustion gas from the combustor to the heat processing appliance, and is the combustion device for the ammonia mixed fuel according to any one of claims 35 to 38.

42. A power generation facility for generating electricity in any one of land, water, and airspace, comprising at least one of the combustion device for the ammonia mixed fuel provided with the internal combustion engine according to claim 39 and the combustion device for the ammonia mixed fuel provided with the external combustion engine according to claim 40, a generator configured to generate electricity by using the mechanical power extracted from the energy of the combustion gas of the ammonia mixed fuel by at least one of the internal combustion engine and the external combustion engine, a power output terminal configured to output the electricity generated by the generator, and a control mechanism configured to control the amount of electric power at the power output terminal. The power generation facility is characterized by comprising these components.

43. A transportation device configured to move or transport goods in any one of land, water, and airspace, comprising At least one of the combustion devices for ammonia mixed fuel equipped with the internal combustion engine according to claim 39 and the combustion device for ammonia mixed fuel equipped with the external combustion engine according to claim 40 is mounted. A power conversion transmission mechanism is provided, which is configured to utilize, as at least part of the power for propelling the transportation device, the mechanical power extracted from the energy of the combustion gas of the ammonia mixed fuel by at least one of the internal combustion engine and the external combustion engine. A transportation device characterized by this.

44. A transportation device configured to move or transport materials in any one of land, water, and airspace, The power generation facility according to claim 42 is mounted. An electric propulsion mechanism configured to use, as at least part of the required power in the propulsion of the transportation device, the electric power output from the power generation facility by utilizing the energy of the combustion gas of the ammonia mixed fuel. An operation control mechanism configured to use the electric power as at least part of the required power in the operation control of the transportation device, and A transportation device characterized by including at least one of a power supply mechanism for maintenance configured to use the electric power as at least part of the required power in the maintenance of the transportation device.

45. Furthermore, a power conversion transmission mechanism is further provided, which is provided in the power generation facility and is configured to convert and use, as at least part of the power for propelling the transportation device, the mechanical power extracted from the energy of the combustion gas of the ammonia mixed fuel by at least one of the internal combustion engine and the external combustion engine. The transportation device according to claim 44.

46. A method for manufacturing ammonia mixed fuel, (1) Liquid ammonia and (a) Liquefied petroleum gas, naphtha, gasoline, kerosene, and light oil (b) a hydrocarbon for raw materials, which is at least one hydrocarbon species contained as a component in any one of the liquefied petroleum gas, the naphtha, the gasoline, the kerosene, and the light oil, and (c) an alcohol for raw materials, which is an alcohol having 3 or less carbon atoms, at least one of which is introduced into a sealed mixing container as a combustion aid for assisting the combustion of the ammonia, (2) While maintaining the ammonia and the combustion aid in a vapor-liquid equilibrium state leaving a liquid phase portion in the sealed mixing container, the ammonia and the combustion aid are stirred and mixed, so that at least a part of the liquid phase portion of the ammonia and the combustion aid becomes a solution state in which the ammonia and the combustion aid are dissolved in each other, or a mixture in an emulsion state of the ammonia and the combustion aid is produced, (3) The mixture is discharged from the sealed mixing container as an ammonia-mixed fuel. A method for producing an ammonia-mixed fuel, characterized by the above.

47. When introducing the ammonia and the combustion aid into the sealed mixing container and stirring and mixing them, the temperature of the mixture of the ammonia and the combustion aid is adjusted so that the saturated vapor pressures of the ammonia and the combustion aid in the sealed mixing container do not exceed the set pressure resistance of the sealed mixing container. The method for producing an ammonia-mixed fuel according to claim 46.

48. When producing the mixture, the liquid ammonia and the liquid combustion aid are introduced into the sealed mixing container in a predetermined quantitative ratio, while stirring and mixing the ammonia and the combustion aid in the sealed mixing container, the temperature of the mixture is adjusted so that the entire liquid phase portion of the mixture is within a temperature range in which the ammonia and the combustion aid are in a solution state in which they are dissolved in each other or an emulsion state of the ammonia and the combustion aid according to the predetermined quantitative ratio. The method for producing an ammonia-mixed fuel according to claim 46 or 47.

49. The ammonia mixed fuel contains, as the combustion improver, at least one of the liquefied petroleum gas, the hydrocarbon for raw materials, and the alcohol for raw materials. The hydrocarbon for raw materials is at least one hydrocarbon species contained as a component in the liquefied petroleum gas. The alcohol for raw materials is methanol. The method for producing an ammonia mixed fuel according to any one of claims 46 to 48.

50. When discharging the mixture from the mixing sealed container, nitrogen gas is injected into the mixing sealed container at a discharge pressure equal to or higher than the saturated vapor pressure of the mixture in the mixing sealed container. The method for producing an ammonia mixed fuel according to any one of claims 46 to 49.

51. When discharging the mixture from the mixing sealed container, while continuously supplementing ammonia into the mixing sealed container at a flow rate equal to the discharge flow rate of the ammonia contained in the mixture discharged from the mixing sealed container and continuing stirring and mixing, and in parallel, while continuously supplementing the combustion improver into the mixing sealed container at a flow rate equal to the discharge flow rate of the combustion improver contained in the mixture discharged from the mixing sealed container and continuing stirring and mixing, the ammonia mixed fuel with a constant mixing composition of the ammonia and the combustion improver is continuously produced. The method for producing an ammonia mixed fuel according to any one of claims 46 to 49.

52. When preparing the mixture, a surfactant is introduced into the mixing sealed container together, and by stirring and mixing with the ammonia and the combustion improver, the surfactant is included as one component of the mixture to prepare the mixture in an emulsion state. The method for producing an ammonia mixed fuel according to any one of claims 46 to 50.

53. When preparing the mixture, the surfactant is introduced into the mixing sealed container so that the concentration of the surfactant in the mixture is 0.1 to 10% by mass. The method for producing an ammonia mixed fuel according to claim 52.

54. When continuously producing the ammonia mixed fuel in which the mixing composition of the ammonia and the combustion aid is maintained constant by the method according to claim 51, when discharging the mixture from the sealed mixing container, further, while continuously replenishing the surfactant into the sealed mixing container at a flow rate equal to the discharge flow rate of the surfactant contained in the mixture discharged from the sealed mixing container, by continuously stirring and mixing, the ammonia mixed fuel in which the concentration of the surfactant is maintained constant is continuously produced. The method for producing an ammonia mixed fuel according to claim 52 or 53.

55. The surfactant contains at least one nonionic surfactant and at least one ionic surfactant. The method for producing an ammonia mixed fuel according to any one of claims 52 to 54.

56. The surfactant is (A) In the molecular structure, a primary or secondary amino group [-NH ２ , or >NH], a polyoxyalkylene amino group [>N(C ａ H ２ａ O) ｃ -H, or -N((C ｂ H ２ｂ O) ｄ -H)((C ｂ H ２ｂ O) ｅ -H)] (a and b are 2 or 3, c is an integer from 1 to 8, d and e are 0 or positive integers such that d + e = 1 to 8), an amide group [-C(=O)NH ２ , a polyoxyalkylene amide group [-C(=O)N((C ｆ H ２ｆ O) ｇ -H)((C ｆ H ２ｆ O) ｈ -H)] (f is 2 or 3, g and h are 0 or positive integers such that g + h = 1 to 8), and a polyoxyalkylene group [-O(C ｉ H ２ｉ O) ｊ-[H] (where i is 2 or 3 and j is an integer from 1 to 8), having at least one group as a nonionic polar site among them, and having at least one group as a nonpolar site among an alkyl group [C ｋ H ２ｋ＋１ -] (where k is an integer from 7 to 18) and an alkenyl group [C ｌ H ２ｌ－１ -] (where l is an integer from 7 to 18), at least one of the above nonionic surfactants, (B) In the molecular structure, a quaternary methylammonium group, a quaternary methylalkanolammonium group, or a quaternary alkanolammonium group [-N ＋ (CH ３ ) ｐ (C ｍ H ２ｍ OH) ｑ ·X － , or >N ＋ (CH ３ ) ｒ (C ｎ H ２ｎ OH) ｓ ·X' － (where m and n are 2 or 3, p and q are 0 or positive integers such that p + q = 3, r and s are 0 or positive integers such that r + s = 2, and X and X' are any of Cl, Br, and I), and a carboxyl group [-C(=O)OH], having at least one group as an ionic polar site among them, and having at least one group as a nonpolar site among an alkyl group [C ｔ H ２ｔ＋１ -] (where t is an integer from 7 to 18) and an alkenyl group [C ｕ H ２ｕ－１ -] (where u is an integer from 7 to 18), at least one of the above ionic surfactants, The method for producing an ammonia mixed fuel according to claim 55, comprising.

57. When introducing all the introduction targets into the closed mixing container including the ammonia and the combustion aid into the closed mixing container, for all the introduction targets to be introduced, they are introduced into the closed mixing container in order from the introduction target with a lower saturated vapor pressure at the temperature in the closed mixing container. The method for producing an ammonia mixed fuel according to any one of claims 46 to 56.

58. When the ammonia and the combustion aid are stirred and mixed in the closed mixing container, so that the entire liquid phase portion of the mixture becomes a solution state or an emulsion state, the ammonia and the combustion aid are introduced into the closed mixing container in a predetermined quantitative ratio, and the stirring and mixing in the closed mixing container maintained at a predetermined liquid phase temperature are performed. By discharging the liquid phase portion from the closed mixing container, an ammonia mixed fuel in which the ammonia and the combustion aid are in a solution state or an emulsion state at a composition ratio within a predetermined range is produced. The method for producing an ammonia mixed fuel according to any one of claims 46 to 57.

59. The combustion aid is at least one of those described in (a) and (b) above. When the ammonia and the combustion aid are stirred and mixed in the closed mixing container, so that the liquid phase portion of the mixture separates into upper and lower two layers, and the entire of each of the liquid phase portions separated into the upper and lower two layers becomes a solution state or an emulsion state, the ammonia and the combustion aid are introduced into the closed mixing container in a predetermined quantitative ratio, and the stirring and mixing in the closed mixing container maintained at a predetermined liquid phase temperature are performed. By discharging at least one of the liquid phase portions of the upper and lower two layers from the closed mixing container, one or two ammonia mixed fuels in which the ammonia and the combustion aid are in a solution state or an emulsion state at one or two predetermined composition ratios are produced. The method for producing an ammonia mixed fuel according to claim 46.

Images