Condensing device

Abstract

Provided is a condensing device capable of saving energy in a process for condensing a gas, particularly in a process for condensing a fuel gas into a liquid fuel. A condensing device according to an embodiment of the present invention is provided with: a gas separator to which a mixed gas is supplied, the gas separator being capable of separating the mixed gas into a first gas and a second gas; a decompression device capable of decompressing the second gas; and a cooling device capable of cooling the second gas, the condensing device being configured such that the Joule-Thomson coefficient of the second gas is greater than the Joule-Thomson coefficient of the mixed gas by means of the gas separator.

Description

TECHNICAL FIELD

[0001] The present application relates to a condensing device. BACKGROUND

[0002] In recent years, for the purpose of realizing a carbon neutral society, it has been proposed to capture carbon monoxide, carbon dioxide and the like as carbon resources, and to convert them into useful liquid fuels using them as industrial base materials. For example, Patent Literature 1 discloses a method for producing methanol, in which a raw material synthesis gas is introduced into a methanol synthesis reactor, and a part of the raw material synthesis gas is converted into methanol.

[0003] In the method for producing methanol described in Patent Literature 1, a gas containing methanol is cooled, and the methanol is condensed, and the liquid crude methanol and unreacted gas are separated. However, at present, in a reaction system for synthesizing liquid fuels from carbon oxides like this, a very large amount of energy (heat removal energy) is required to condense fuel components in a gaseous state into a liquid state, and various research subjects remain in view of practical use.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2020-63193 SUMMARY

[0007] The present application relates to a condensing device.

[0008] [1] The condensing device according to an embodiment of the present application includes a gas separator, a pressure reducing device, and a cooling device. The gas separator is supplied with a mixed gas containing a fuel gas. The gas separator is capable of separating the mixed gas into a first gas and a second gas containing the fuel gas. The pressure reducing device is capable of reducing the pressure of the second gas. The cooling device is capable of cooling the second gas. The condensing device is configured such that the Joule-Thomson coefficient of the second gas is greater than the Joule-Thomson coefficient of the mixed gas by means of the gas separator.

[0009] [2] The condensing device according to the above [1] can further include at least one reactor. The at least one reactor is disposed on the upstream side of the gas separator in the supply direction of the mixed gas to the gas separator. The reactor is supplied with a raw material gas containing carbon oxides and hydrogen. The reactor is capable of discharging a mixed gas containing a fuel gas which is a reaction product of carbon oxides and hydrogen, and a raw material gas which remains unreacted.

[0010] [3] The condensing device according to any one of [2], wherein the gas separator is capable of separating the mixed gas supplied from the reactor into a first gas containing hydrogen as a main component and a second gas containing the fuel gas.

[0011] [4] The condensing device according to any one of [2] or [3], further comprising a return line. The return line returns a gas component remaining in a gas state even after the pressure reduction and the cooling in the second gas to the reactor.

[0012] [5] The condensing device according to [3], further comprising a gas-liquid separator. The gas-liquid separator is disposed on a downstream side of the gas separator in a discharge direction in which the second gas is discharged from the gas separator. The gas-liquid separator is capable of separating a liquid fuel condensed by the pressure reduction and the cooling in the second gas and a gas component remaining in a gas state even after the pressure reduction and the cooling in the second gas.

[0013] [6] The condensing device according to any one of [2] to [5], wherein the reactor is a membrane reactor.

[0014] [7] The condensing device according to any one of [1] to [6], wherein a Joule-Thomson coefficient of the second gas is 15.9 K / MPa or less.

[0015] [8] The condensing device according to any one of [1] to [7], wherein the liquid fuel contains an alcohol as a main component.

[0016] [9] The condensing device according to any one of [1] to [8], wherein the condensing device is a fuel gas condensing device.

[0017] Effects of Invention

[0018] According to the embodiment of the present application, energy saving in a process of condensing a gas, particularly a process of condensing a fuel gas into a liquid fuel, can be achieved. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a schematic configuration view of a fuel gas condensing device according to an embodiment of the present application.

[0020] Figure 2 is a schematic configuration view of a fuel gas condensing device according to another embodiment of the present application.

[0021] Figure 3 is Figure 1 a schematic cross-sectional view of a reactor included in the fuel gas condensing device of

[0022] Figure 4 isFigure 1 A schematic cross-sectional view of another embodiment of the reactor provided in the fuel gas condensation device.

[0023] Figure 5 yes Figure 1 A schematic cross-sectional view of another embodiment of the reactor provided in the fuel gas condensation device.

[0024] Figure 6 yes Figure 5 A schematic three-dimensional diagram of the separation membrane complex of the reactor. Detailed Implementation

[0025] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings; however, the present invention is not limited to these embodiments. Furthermore, to make the description clearer, the drawings sometimes schematically show the width, thickness, shape, etc., of each part compared to the embodiments; however, this is merely an example and does not limit the interpretation of the present invention.

[0026] A. Overview of the fuel gas condensation unit

[0027] Figure 1 This is a schematic diagram of a fuel gas condensation apparatus according to one embodiment of the present invention. Figure 2 This is a schematic diagram of a fuel gas condensation device according to another embodiment of the present invention.

[0028] In one embodiment, the condensation device is a fuel gas condensation device 100. Typically, the fuel gas condensation device 100 illustrated in the figures is capable of condensing fuel gas to produce liquid fuel. That is, the fuel gas condensation device 100 can implement a liquid fuel production method.

[0029] like Figure 1 As shown, the fuel gas condensation device 100 includes a gas separator 2, a pressure reducing device 53, and a cooling device 31. The gas separator 2 is supplied with a mixture containing fuel gas. The gas separator 2 can separate the mixture into a first gas and a second gas containing fuel gas. Typically, the second gas is separated in the gas separator 2 and then discharged from the gas separator 2. In the example shown, the pressure reducing device 53 and the cooling device 31 are respectively arranged downstream of the gas separator 2 in the discharge direction from which the second gas is discharged. The pressure reducing device 53 can reduce the pressure of the second gas. The cooling device 31 can cool the second gas. The fuel gas condensation device 100 is configured such that, by means of the gas separator 2, the Joule-Thomson coefficient of the second gas is greater than the Joule-Thomson coefficient of the mixture.

[0030] The inventors of this invention discovered that when cooling fuel gases to condense them, gas components different from the fuel gases present in the gas mixture (especially hydrogen) constitute a significant energy consumption. Therefore, they conducted in-depth research on liquid fuel separation and recovery mechanisms, and found that by separating a gas mixture containing fuel gases into a first gas and a second gas containing fuel gases, and by making the Joule-Thomson coefficient of the second gas greater than that of the gas mixture, and then depressurizing and cooling the second gas, it is possible to condense the gas components contained in the second gas, especially the fuel gases, in an energy-efficient manner.

[0031] Specifically, gas separator 2 can separate a gas mixture into a first gas and a second gas containing fuel gas. The Joule-Thomson coefficient (hereinafter referred to as the JT coefficient) of the separated second gas is greater than that of the gas mixture before separation. This means that the temperature drop of the second gas during depressurization is greater compared to that of the gas mixture. In other words, gas separator 2 can perform a gas separation process that separates the gas mixture into the first gas and the second gas in such a way that the JT coefficient satisfies the above relationship.

[0032] Therefore, if the second gas, with its JT coefficient adjusted in this way, is depressurized by the depressurization device 53 (depressurization process) and cooled by the cooling device 31 (cooling process), even gases with the same heat capacity can be efficiently cooled, thereby reducing the heat removal energy required for the condensation of the gas components contained in the second gas, especially the fuel gas. Thus, the fuel gas can be condensed into liquid fuel in an energy-saving manner.

[0033] In this manual, "liquid fuel" refers to fuel that is in a liquid state at normal temperature and pressure, or fuel that can be liquefied under normal temperature and pressure.

[0034] Examples of fuels that are liquid at room temperature and pressure include methanol, ethanol, and other alcohols; with C n H 2（m－2n） Hydrocarbons (where m is an integer less than 90 and n is an integer less than 30); and mixtures thereof.

[0035] Examples of fuels that can be liquefied under normal temperature and pressure include propane, butane, and mixtures thereof.

[0036] In one embodiment, the liquid fuel contains alcohols as its main component. When the main component of the liquid fuel is a hydrocarbon, components of the gas separator (typically a hydrogen separation membrane) may become clogged, leading to a reduction in the gas separator's function. In contrast, if the main component of the liquid fuel is an alcohol, the gas separator's function can be adequately maintained. It should be noted that the main component refers to the component with the highest proportion in the composition.

[0037] In the above embodiments, the condensing device condenses the fuel gas; however, the present invention is not limited thereto. For example, the condensing device can condense gas components contained in the second gas that are other than the fuel gas (hereinafter referred to as other gas components). Examples of other gas components include, for instance, byproduct gases generated in the reactor as described later. If the condensing device condenses the impurity gases, impurities can be removed from the fuel gas in an energy-efficient manner.

[0038] In one embodiment, the fuel gas condensation apparatus 100 further includes at least one reactor 1. The at least one reactor 1 is disposed upstream of the gas separator 2 in the supply direction for supplying the mixed gas to the gas separator 2. The reactor 1 is supplied with a feed gas containing carbon oxides and hydrogen. The reactor 1 is capable of discharging the mixed gas. The mixed gas contains fuel gas as a reaction product of carbon oxides and hydrogen, and unreacted feed gas residue. The reactor 1 is located on the opposite side of the pressure reducing device 53 relative to the gas separator 2. The liquid fuel condensation apparatus 100 may further include a supply section 4 for supplying feed gas to the reactor 1. Typically, the supply section 4 includes a supply line 41 through which the feed gas passes.

[0039] The feed gas, as described above, contains carbon oxides and hydrogen.

[0040] Examples of carbon oxides include carbon dioxide (CO2) and carbon monoxide (CO). The feed gas may contain only carbon oxides or two or more. Among the carbon oxides, carbon dioxide (CO2) is preferred, and carbon dioxide (CO2) recovered from the atmosphere using direct air recovery technology (DAC) is more preferred.

[0041] The proportions of carbon oxide and hydrogen in the feed gas can be adjusted appropriately based on the conversion reaction carried out in reactor 1.

[0042] Reactor 1 is capable of carrying out a conversion reaction (reaction step) involving the oxidation of carbon and hydrogen. Examples of such conversion reactions include methanol synthesis and ethanol synthesis, with methanol synthesis being a preferred example.

[0043] The methanol synthesis reaction can include the reactions shown in equations (1) to (3).

[0044]

[0045] The reactions in equations (1) to (3) above are all equilibrium reactions. Therefore, carbon oxide and hydrogen preferably react under high temperature and high pressure. This allows for an increase in conversion rate and reaction rate.

[0046] The following explanation uses the synthesis of methanol as an example.

[0047] The pressure inside reactor 1 is, for example, 1.2 MPa (absolute pressure) or more, preferably 3.0 MPa (absolute pressure) or more, more preferably 3.5 MPa (absolute pressure) or more, and even more preferably 4.0 MPa (absolute pressure) or more. On the other hand, the pressure inside reactor 1 is, for example, 7.0 MPa (absolute pressure) or less, preferably 5.5 MPa (absolute pressure) or less. If the pressure inside reactor 1 is within the above range, the pressure of the mixed gas discharged from the reactor can also be adjusted to the above range. If the pressure of the mixed gas is within the above range, the first gas containing hydrogen as the main component and the second gas containing fuel gas can be efficiently separated in a gas separator using the pressure of the mixed gas.

[0048] The temperature inside reactor 1 is, for example, 200°C or higher, preferably 210°C or higher, and more preferably 220°C or higher. On the other hand, the temperature inside reactor 1 is, for example, 320°C or lower, preferably 300°C or lower, and more preferably 290°C or lower. If the temperature inside reactor 1 is within the above range, the temperature of the mixed gas discharged from the reactor can also be adjusted to the above range. If the temperature of the mixed gas is within the above range, liquefaction of fuel gas in the gas separator can be suppressed.

[0049] As described above, the mixed gas discharged from reactor 1 contains fuel gas (typically methanol gas) as a reaction product and unreacted feed gas (typically hydrogen, or hydrogen and carbon oxide). The mixed gas may further contain byproduct gases generated during the aforementioned conversion reaction.

[0050] The proportion of fuel gas in the gas mixture is, for example, 1.0 mol% or more, preferably 3.0 mol% or more. On the other hand, the proportion of fuel gas in the gas mixture is, for example, 60.0 mol% or less, and also, for example, 55.0 mol% or less. It should be noted that the proportions of each gas can be determined using gas chromatography or the like.

[0051] The proportion of the feed gas in the gas mixture is, for example, 2.0 mol% or more, preferably 3.0 mol% or more. On the other hand, the upper limit of the proportion of the feed gas in the gas mixture is typically 90 mol%.

[0052] Reactor 1 and gas separator 2 can be directly connected, or a pressurizing device and / or a depressurizing device can be installed between reactor 1 and gas separator 2. The pressurizing device can increase the pressure of the mixed gas being transported from reactor 1 to gas separator 2. Examples of pressurizing devices include compressors and blowers. The depressurizing device can reduce the pressure of the mixed gas being transported from reactor 1 to gas separator 2. Examples of depressurizing devices include pressure reducing valves.

[0053] Furthermore, a removal device capable of removing a portion of the gaseous components contained in the mixed gas can be installed between reactor 1 and gas separator 2. With this configuration, even if the mixed gas discharged from the reactor contains gaseous components that degrade the performance of the gas separator, these components can be removed by the removal device. Therefore, performance degradation of the gas separator can be suppressed, thereby ensuring the long-term performance of the gas separator.

[0054] In one embodiment, a gas separator 2 is disposed directly below the reactor 1, and the reactor 1 and the gas separator 2 are directly connected. With this configuration, compared to the case where a pressure reducing device and / or a removal device are provided between the reactor and the gas separator, the pressure energy loss of the mixed gas can be reduced. Furthermore, since a mixed gas with sufficient pressure can be supplied to the gas separator without a pressure boosting device, the power required to drive the pressure boosting device can be reduced.

[0055] In the example shown, the fuel gas condensation device 100 also includes a first connecting line 51 capable of supplying the mixed gas discharged from the reactor 1 to the gas separator 2. The first connecting line 51 directly connects the reactor 1 and the gas separator 2.

[0056] After the mixed gas is supplied to gas separator 2, it is separated into a first gas containing hydrogen as the main component and a second gas containing fuel gas. In other words, gas separator 2 separates the mixed gas supplied from reactor 1 into a first gas containing hydrogen as the main component and a second gas containing fuel gas (gas separation process). This reduces the amount of hydrogen in the second gas, thus significantly increasing the JT coefficient of the separated second gas. This means a greater temperature reduction during depressurization of the second gas, allowing for more energy-efficient condensation of the fuel gas contained in the second gas, even for gases with the same heat capacity.

[0057] In the example shown, the condensing device 100 includes one gas separator; however, the number of gas separators is not limited to this. The condensing device 100 may include multiple gas separators. By changing the number of gas separators as needed, the composition of the first gas and the second gas can be controlled.

[0058] The pressure of the mixed gas to be supplied to the gas separator 2 is, for example, 1.2 MPa (absolute pressure) to 7.0 MPa (absolute pressure), preferably 3.0 MPa (absolute pressure) to 5.5 MPa (absolute pressure).

[0059] The temperature of the mixed gas to be supplied to the gas separator 2 is, for example, 200°C to 320°C, preferably 210°C to 300°C.

[0060] The JT coefficient of the mixed gas to be supplied to gas separator 2 is, for example, 0.7 K / MPa to 10.4 K / MPa.

[0061] It should be noted that the JT coefficient of the mixed gas can be calculated by the sum of (the JT coefficient of each gas component contained in the raw gas) × (the composition ratio of that gas component).

[0062] The first gas separated in gas separator 2 can be used for any suitable purpose. It can be used as fuel for peripheral equipment or as a feedstock for other conversion reactions. The second gas separated in gas separator 2 will be described in detail below, and it is conveyed from gas separator 2 to pressure reducing device 53 or cooling device 31.

[0063] The gas separator 2 can be configured in any suitable way. In one embodiment, the gas separator 2 includes a hydrogen separation membrane that allows hydrogen to pass through. With such a configuration, the pressure of the mixed gas can be effectively utilized to more smoothly separate the first gas into a second gas. As such a gas separator 2, for example, the DDR type zeolite membrane described in Japanese Patent Application Publication No. 2004-105942 can be cited. The entire description of that publication is incorporated herein by reference.

[0064] The hydrogen content in the first gas is, for example, 50 mol% or more, preferably 70 mol% or more. On the other hand, the hydrogen content in the first gas is, for example, 100 mol% or less, and also, for example, 90 mol% or less.

[0065] When the amount of hydrogen contained in the mixed gas discharged from reactor 1 is set to 1 on a molar basis, the amount of hydrogen contained in the first gas is, for example, 0.80 or more, preferably 0.90 or more. If the first gas contains such an amount of hydrogen, the amount of hydrogen remaining in the second gas can be sufficiently reduced, thereby sufficiently reducing the energy (excluding thermal energy) required to cool the second gas during fuel gas condensation. On the other hand, when the amount of hydrogen contained in the mixed gas discharged from reactor 1 is set to 1 on a molar basis, the amount of hydrogen contained in the first gas is, for example, 1.0 or less. If the first gas contains such an amount of hydrogen, the liquefaction of fuel gas within the gas separator can be stably suppressed, resulting in improved efficiency in liquid fuel production.

[0066] In addition to hydrogen, the first gas may also contain carbon oxide.

[0067] The carbon oxide content in the first gas is, for example, 0 mol% or more, preferably 10 mol% or more. On the other hand, the carbon oxide content in the first gas is, for example, less than 50 mol%, and also, for example, 30 mol% or less.

[0068] When the amount of carbon oxide contained in the mixed gas is set to 1 on a molar basis, the amount of carbon oxide contained in the first gas is, for example, 0.60 or more, preferably 0.70 or more. On the other hand, when the amount of carbon oxide contained in the mixed gas is set to 1 on a molar basis, the amount of carbon oxide contained in the first gas is, for example, 0.80 or less.

[0069] Furthermore, the first gas substantially contains no fuel gas. The proportion of fuel gas in the first gas is, for example, 1.0 mol% or less, preferably 0.5 mol% or less, more preferably 0.1 mol% or less, and even more preferably 0 mol%.

[0070] The second gas separated in gas separator 2 contains at least fuel gas (representatively methanol gas).

[0071] The fuel gas content in the second gas is, for example, 9.0 mol% or more, preferably 15.0 mol% or more. On the other hand, the fuel gas content in the second gas is, for example, 95.0 mol% or less, and also, for example, 85.0 mol% or less. If the fuel gas content in the second gas is at or above the above lower limit, liquid fuel can be efficiently recovered in the gas-liquid separator.

[0072] In addition to fuel gases, the second gas also includes raw material gases (representatively carbon oxides, or hydrogen and carbon oxides), and / or impurity gases such as byproduct gases.

[0073] Typically, the pressure of the second gas is lower than the pressure of the mixed gas discharged from reactor 1.

[0074] Gas separator 2 can separate the second gas at atmospheric pressure (0.1 MPa) or at pressurized pressure (above 0.1 MPa). When gas separator 2 is equipped with a hydrogen separation membrane, it can stably separate the second gas under pressurized conditions. In this case, the pressurized second gas is discharged from gas separator 2.

[0075] The pressure of the second gas under pressurization is preferably 3.0 MPa (absolute pressure) or more, more preferably 3.3 MPa (absolute pressure) or more. On the other hand, the pressure of the second gas under pressurization is, for example, 6.8 MPa (absolute pressure) or less, preferably 5.3 MPa (absolute pressure) or less, more preferably 5.0 MPa (absolute pressure) or less.

[0076] The temperature of the second gas is, for example, 200°C or higher, preferably 210°C or higher, and more preferably 220°C or higher. On the other hand, the upper limit of the temperature of the second gas is typically 300°C.

[0077] The JT coefficient of the second gas is, for example, greater than 0.7 K / MPa. On the other hand, the upper limit of the JT coefficient of the second gas is typically 15.9 K / MPa. In other words, the gas separator can separate hydrogen from the mixed gas with the second gas having a JT coefficient in such a range. If the JT coefficient of the second gas immediately after separation is in such a range, the second gas can be cooled efficiently by depressurizing it. Therefore, the heat removal energy required for the condensation of the fuel gas can be reduced. In addition, if the JT coefficient of the second gas is in such a range, membrane costs and feedstock losses can be suppressed.

[0078] It should be noted that the JT coefficient of the second gas can be calculated by the sum of (the JT coefficients in the partial pressures of the gas components contained in the second gas) × (the composition ratio of the gas components).

[0079] The difference between the JT coefficient of the second gas and the JT coefficient of the mixed gas (JT coefficient of the second gas - JT coefficient of the mixed gas) is, for example, greater than 0 K / MPa and less than 13.1 K / MPa. In other words, the gas separator can separate hydrogen from the mixed gas in such a range that the difference between the JT coefficient of the second gas immediately after separation and the JT coefficient of the mixed gas before separation is within such a range. If the difference in the JT coefficients between the second gas and the mixed gas is adjusted in this way, the efficiency of the second gas can be better reduced by depressurizing the second gas. In addition, if the difference in the JT coefficients between the second gas and the mixed gas is within such a range, membrane costs and feed loss can be suppressed.

[0080] Although not illustrated, the fuel gas condensation device 100 may include multiple reactors 1 and multiple gas separators 2. In this embodiment, the reactors 1 and gas separators 2 are arranged alternately in the gas flow direction. The mixed gas discharged from the reactor 1 is supplied to the gas separator 2 located downstream of the reactor 1, where it is separated into a first gas and a second gas. The second gas separated in the gas separator 2 is then supplied to the next reactor 1. If the second gas contains residual feed gas, that feed gas is used in the aforementioned conversion reaction in the reactor 1.

[0081] In one embodiment, the difference between the JT coefficient of the second gas separated by the gas separator 2 located at the downstream end of the gas separator 2 in the gas passage direction and the JT coefficient of the mixed gas supplied to the gas separator 2 is adjusted to the range of the aforementioned JT coefficient difference.

[0082] Typically, the pressure reducing device 53 is positioned on the opposite side of the reactor 1 relative to the gas separator 2. In one embodiment, the pressure reducing device 53 is capable of reducing the pressure of the second gas between the gas separator 2 and the cooling device 31. That is, the pressure reducing device 53 is capable of performing a pressure reducing process to reduce the pressure of the second gas.

[0083] In the example shown, the fuel gas condensation device 100 further includes a second connecting line 52 capable of supplying the second gas separated by the gas separator 2 to the gas-liquid separator 32, and a pressure reducing device 53 is disposed on the second connecting line 52. The pressure reducing device 53 is typically a pressure reducing valve.

[0084] More specifically, the pressure reducing device (pressure reducing valve 53) can reduce the pressure of the second gas to, for example, below 5.0 MPa (absolute pressure), or, for example, atmospheric pressure (0.1 MPa). Thus, the second gas is sufficiently cooled, further reducing the heat loss energy of the second gas.

[0085] The second gas is cooled by the cooling device 31 (cooling process). In one embodiment, the cooling device 31 is disposed on the opposite side of the gas separator 2 relative to the pressure reducing device 53, and cools the pressure-reduced second gas to the cooling temperature described later. In the example shown, the cooling device 31 is located downstream of the pressure reducing device 53 in the discharge direction from the gas separator 2, and is provided on the second connecting line 52. The cooling device 31 can have any suitable configuration.

[0086] The cooling temperature in the cooling device 31 is typically below the condensation point (boiling point) of the reaction product (fuel gas). The cooling temperature is, for example, below 50°C, and preferably below 40°C. On the other hand, the cooling temperature is, for example, above 0°C, and preferably above 10°C.

[0087] If the second gas is depressurized and cooled, the components contained in the second gas whose boiling points (condensation points) are above the aforementioned cooling temperature (typically fuel gas and a portion of by-product gases) can be stably liquefied to produce liquid fuel. Furthermore, if the cooling temperature is within the aforementioned range, the fuel gas can be liquefied more stably.

[0088] In addition, such as Figure 2 As shown, the cooling device 31 can be installed between the gas separator 2 and the pressure reducing device 53. That is, the cooling device 31 can be located upstream of the pressure reducing device 53 in the discharge direction of the second gas discharged from the gas separator 2. In this case, the second gas separated by the gas separator 2 is first cooled to the aforementioned cooling temperature by the cooling device 31, and then its pressure is reduced by the pressure reducing device 53. As a result, the components in the second gas whose boiling point (condensation point) is above the aforementioned cooling temperature can be fully liquefied to produce liquid fuel.

[0089] That is, the cooling process can be carried out after the decompression process or before the decompression process.

[0090] In one embodiment, the liquid fuel condensation device 100 further includes a gas-liquid separator 32. The gas-liquid separator 32 is disposed downstream of the gas separator 2 in the discharge direction from which the second gas is discharged. In the example shown, the gas-liquid separator 32 is located downstream of the pressure reducing device 53 and the cooling device 31. The gas-liquid separator 32 is capable of separating the liquid fuel condensed due to pressure reduction and cooling from the gaseous components remaining in the second gas even after pressure reduction and cooling. In other words, the gas-liquid separator 32 can perform a gas-liquid separation process to separate the liquid fuel and the gaseous components.

[0091] The gas-liquid separator 32 is typically a separation tank. Liquid fuel and gaseous components with boiling points (condensation points) below the aforementioned cooling temperature (typically, the feed gas and a portion of the byproducts) are supplied to the separation tank in a mixed state and stored thereon, thereby separating the liquid fuel and gaseous components into gas and liquid components.

[0092] The liquid fuel contains at least reaction products in a liquid state. The proportion of reaction products in the liquid fuel is, for example, 15.0 mol% or more, preferably 20.0 mol% or more, and more preferably 50.0 mol% or more. On the other hand, the upper limit of the proportion of reaction products in the liquid fuel is typically 100 mol%.

[0093] In addition to reaction products, liquid fuels may also contain liquid byproducts. The proportion of byproducts in the liquid fuel is, for example, 85.0 mol% or less, preferably 80 mol% or less, and more preferably 50.0 mol% or less. On the other hand, the lower limit of the proportion of byproducts in the liquid fuel is typically 0 mol%.

[0094] Liquid fuel is supplied to the by-product removal process as needed. This allows for an increase in the proportion of reaction products contained in the liquid fuel.

[0095] In one embodiment, the fuel gas condensation device 100 further includes a recovery line 9 capable of recovering the liquid fuel separated by the gas-liquid separator 32. In the example shown, the upstream end of the recovery line 9 is connected to the bottom of the separator 32. Although not shown, however, the downstream end of the recovery line 9 is connected to a fuel tank capable of storing the liquid fuel.

[0096] In one embodiment, the fuel gas condensation device 100 further includes a return line 6. The return line 6 is capable of returning gaseous components that remain in a gaseous state from the second gas discharged from the gas separator 2 even after depressurization and cooling. In other words, the fuel gas condensation device 100 can perform a return process that returns gaseous components to the reactor 1.

[0097] In the example shown, the return line 6 can return the gas components separated by the gas-liquid separator 32 to the reactor 1. The upstream end of the return line 6 is connected to the upper part of the separator 32. Although not shown, the downstream end of the return line 6 is connected to the supply unit 4. Thus, the gas components can be supplied back to the reactor and reused as feed gas.

[0098] In the above embodiments, a raw material gas containing hydrogen is supplied to reactor 1, and the mixed gas discharged from reactor 1 contains unreacted and residual hydrogen. However, the present invention is not limited thereto.

[0099] The mixed gas discharged from reactor 1 may contain hydrogen produced in reactor 1. In this case, the first gas separated by gas separator 2 contains hydrogen produced in reactor 1. In one embodiment, the reactor is capable of performing an aqueous gas shift reaction, supplying the mixed gas produced by the aqueous gas shift reaction from the reactor to the gas separator, where it is separated into a first gas and a second gas.

[0100] The condensation apparatus 100 for fuel gas, as described above, can implement a method for manufacturing liquid fuel. The method for manufacturing liquid fuel includes the gas separation step, the pressure reduction step, and the cooling step described above. In one embodiment, the method for manufacturing liquid fuel further includes the reaction step described above. Additionally, the method for manufacturing liquid fuel may further include the gas-liquid separation step and / or a return process described above.

[0101] The specific composition of the reactor will be described below.

[0102] B. Reactor

[0103] Reactor 1 can be constructed in any suitable manner. There are no particular restrictions on the shape of reactor 1; for example, it can be a monolithic shape, a flat plate, a tube, a cylinder, a prism, etc. A monolithic shape refers to a shape with multiple compartments extending along its length, and includes the concept of a honeycomb shape.

[0104] Examples of reactor 1 components include: membrane reactors, fixed-layer reactors, moving-layer reactors, fluidized-layer reactors, stirred tank reactors, tower reactors, and tubular reactors.

[0105] like Figure 3As shown, in one embodiment, reactor 1 is a tubular reactor 1a.

[0106] Typically, the tubular reactor 1a has: a gas inlet 15 for the feed gas to flow in, a gas outlet 16 for the mixed gas to flow out, and a space 14 connecting them, in which the catalyst 11 is housed. The space 14 functions as a gas flow path. Typically, the downstream end of the supply line 41 is connected to the gas inlet 15. Typically, the upstream end of the first connecting line 51 is connected to the gas outlet 16.

[0107] Catalyst 11 promotes the conversion reaction of the feed gas. Catalyst 11 is preferably packed in flow path 14. When the catalyst is in particle shape as shown in the example, the particle size (diameter) of the catalyst particles is, for example, 0.5 mm or more and 10 mm or less. The catalyst particles may consist solely of catalyst, or they may be composed of catalyst 11 supported on carrier particles. The carrier particles are preferably porous particles.

[0108] As catalyst 11, any suitable catalyst corresponding to the desired conversion reaction can be used. Specifically, the following can be used: metal catalysts (copper, palladium, nickel, ruthenium, rhodium, platinum, etc.), oxide catalysts (zinc oxide, zirconium dioxide, gallium oxide, cerium dioxide, etc.), and catalysts obtained by combining them (copper-zinc oxide, copper-zinc oxide-alumina, copper-zinc oxide-chromium oxide-alumina, copper-cobalt-titanium dioxide, nickel-cerium dioxide, nickel-alumina, ruthenium-cerium dioxide, and catalysts obtained by modifying them with palladium, etc.).

[0109] like Figure 4 As shown, in another embodiment, reactor 1 is a membrane reactor 1b. Typically, membrane reactor 1b includes a water vapor separation membrane 18. In the membrane reactor, while the reaction of carbon oxide and hydrogen is developing, the byproduct water vapor is separated from the mixed gas containing fuel gas and feed gas by passing it through the water vapor separation membrane. This promotes the reaction of carbon oxide and hydrogen.

[0110] The water vapor separation membrane 18 allows water vapor to pass through, while components other than water vapor (such as hydrogen, carbon dioxide, and fuel gases) are less likely to pass through compared to water vapor. Examples of water vapor separation membranes include inorganic membranes and organic membranes.

[0111] Examples of inorganic membranes include zeolite membranes, silica membranes, alumina membranes, and composite membranes thereof. Among inorganic membranes, zeolite membranes are preferred, and LTA-type zeolite membranes with a silicon (Si) to aluminum (Al) molar ratio (Si / Al) of 1.0 or more and 3.0 or less are more preferred.

[0112] Examples of organic membranes include: polyethylene (PE), polyvinylidene fluoride (PVDF), tetrafluoroethylene (PTFE), polypropylene (PP), cellulose acetate (CA), polyacrylonitrile (PAN), polyimide (PI), polysulfone (PS), and polyethersulfone (PES).

[0113] The membrane reactor 1b also includes a porous support 19. The porous support 19 supports the water vapor separation membrane 18. The porous support 19 is made of a porous material. Examples of porous materials include ceramic materials, metal materials, and resin materials, with ceramic materials being preferred.

[0114] Membrane reactor 1b includes a first gas flow path 14 and a second gas flow path 17. The first gas flow path 14 will be described in the same way as the space 14 of the tubular reactor 1a described above. The first gas flow path 14 connects the gas inlet 15 and the gas outlet 16 described above, and houses the catalyst 11 described above. In the example shown, the water vapor separation membrane 18 faces the first gas flow path 14.

[0115] The second gas flow path 17 is located on the opposite side of the first gas flow path 14 relative to the water vapor separation membrane 18. Water vapor that has passed through the water vapor separation membrane 18 can flow into the second gas flow path 17. In addition, purge gas for purging water vapor can be supplied into the second gas flow path 17.

[0116] The membrane reactor 1b can adopt any suitable configuration. There are no particular limitations on the shape of the membrane reactor 1b. Examples of possible shapes for the membrane reactor 1b include: integral shape, flat plate shape, tubular shape, cylindrical shape, prismatic shape, and polygonal shape. An integral shape refers to a shape having multiple compartments extending along its length, and includes the concept of a honeycomb shape.

[0117] Examples of components of membrane reactor 1b include: fixed-layer reactor, moving-layer reactor, fluidized-layer reactor, stirred tank reactor, tower reactor, tubular reactor, and membrane reactor.

[0118] like Figure 5 As shown, in one embodiment, the membrane reactor 1b includes a separation membrane composite 10 and a shell 12.

[0119] The separation membrane composite 10 comprises: a porous support 19 having an integral (honeycomb) shape, and a water vapor separation membrane 18.

[0120] The porous support 19, having an integral shape, can have any suitable shape (overall shape). Typically, the porous support 19 has a column shape extending in a predetermined direction. Examples of shapes for the porous support 19 include: a cylindrical shape with a circular base, an elliptical cylinder with an elliptical base, a prism with a polygonal base, and a column with an irregularly shaped base. The outer diameter and length of the porous support 19 can be appropriately set according to the purpose.

[0121] like Figure 6 As shown, in one embodiment, the porous support 19 is cylindrical. In the example shown, the porous support 19 includes an outer wall 193 and a partition wall 192. The outer wall 193 and the partition wall 192 can be integrally formed or separate. In the example shown, the outer wall 193 and the partition wall 192 are integrally formed.

[0122] The outer wall 193 forms the outer periphery of a porous support 19 with a column shape and has any suitable cylindrical shape.

[0123] The partition 192 is located inside the outer wall 193 and defines multiple compartments 191.

[0124] like Figure 5 As shown, typically, multiple compartments 191 extend from the first end face E1 (upstream end face) to the second end face E2 (downstream end face) of the separation membrane composite 10 along the length direction (axial direction) of the separation membrane composite 10.

[0125] Each of the multiple compartments 191 has an arbitrary and suitable shape in a cross-section in a direction orthogonal to the length direction. Examples of cross-sectional shapes for the compartments 191 include triangles, quadrilaterals, pentagons, polygons of more than one hexagon, circles, and ellipses, with circles being the most preferred.

[0126] The distance between the central axes of the multiple compartments 191 is, for example, 0.3 mm to 20 mm. The compartment density (i.e., the number of compartments 191 per unit area) in the cross-section of the separation membrane composite 10 in a direction orthogonal to the length direction can be appropriately set according to the purpose. The compartment density can be, for example, 0.5 compartments / cm². 2 ~320 compartments / cm 2 If the compartment density is within this range, the strength and effective GSA (geometric surface area) of the porous support can be adequately ensured.

[0127] In the example shown, a water vapor separation membrane 18 is formed on the inner surface of each of the plurality of compartments 191. The water vapor separation membrane 18 may be formed on the entire inner surface of the compartment 191 or on a portion of the inner surface of the compartment 191.

[0128] In one embodiment, the first gas flow path 14 described above is formed in the portion of the cross-section of the compartment 191 where the water vapor separation membrane 18 is not formed (typically the central portion). The first gas flow path 14 extends from the first end face E1 (upstream end face) of the separation membrane composite 10 to the second end face E2 (downstream end face). The first gas flow path 14 has any suitable shape in its cross-section in a direction orthogonal to the length direction. As a cross-sectional shape of the first gas flow path 14, the same cross-sectional shape as that of the compartment 191 described above can be cited.

[0129] As described above, a catalyst 11 is housed in the first gas flow path 14. For convenience, Figure 5 and Figure 6 Catalyst 11 is omitted.

[0130] The housing 12 houses the separation membrane composite 10. More specifically, the housing 12 houses the separation membrane composite 10 in such a way that the first end face E1 and the second end face E2 of the separation membrane composite 10 are exposed.

[0131] In one embodiment, the housing 12 includes: a sidewall 123, an upstream endwall 121, and a downstream endwall 122.

[0132] The sidewall 123 has any suitable cylindrical shape. The shape of the sidewall 123 is appropriately modified according to the shape of the porous support 19. The inner dimension of the sidewall 123 is larger than the outer dimension of the porous support 19.

[0133] In one embodiment, the sidewall 123 of the outer casing 12 is spaced apart from the outer wall 193 of the porous support 19. The aforementioned second flow path 17 is formed between the sidewall 123 of the outer casing 12 and the outer wall 193 of the porous support 19. Gas components (typically water vapor) that have passed through the water vapor separation membrane 18 and the porous support 19 can flow into the second flow path 17.

[0134] In the example shown, the sidewall 123 has an opening 12a. The opening 12a communicates with the second flow path 17. The opening 12a allows gas components (typically water vapor) to be discharged from the second flow path 17.

[0135] Typically, the upstream end wall 121 is located at one end (upstream end) of the housing 12 in the axial direction of the side wall 123. In one embodiment, the upstream end wall 121 has an upstream opening 121a. The upstream opening 121a exposes the first end face E1 (upstream end face) of the separation membrane composite 10. The downstream end of the aforementioned supply line 41 (see reference) is connected to the upstream side wall 121 in a manner communicating with the upstream opening 121a. Figure 1 ).

[0136] Typically, the downstream sidewall 122 is located at the other end (downstream end) of the housing 12 in the axial direction of the sidewall 123. In one embodiment, the downstream sidewall 122 has a downstream opening 122a. The downstream opening 122a exposes the second end face E2 (downstream end face) of the separation membrane composite 10. The upstream end of the aforementioned first connecting line 51 (see reference) is connected to the downstream sidewall 122 in a manner communicating with the downstream opening 122a. Figure 1 ).

[0137] Industrial availability

[0138] The condensation device according to the embodiments of the present invention is used for the condensation of various gases. In particular, liquid fuels such as methanol are liquid at normal temperature and pressure. Therefore, the vapor pressure is reduced, which can effectively condense the gas and facilitate the separation of unreacted gases. Thus, it can be well applied.

[0139] Explanation of reference numerals in the attached figures

[0140] 1. Reactor

[0141] 2 Gas Separator

[0142] 31 Cooler

[0143] 32 Gas-liquid separator

[0144] 53 Pressure reducing device

[0145] 100 Fuel Gas Condensation Device

Claims

1. A condensing device comprising: a gas separator that is supplied with a mixed gas containing a fuel gas, and that is capable of separating the mixed gas into a first gas and a second gas containing the fuel gas; a pressure reducing device that is capable of reducing the pressure of the second gas; and a cooling device that is capable of cooling the second gas, wherein the condensing device is configured so that the Joule-Thomson coefficient of the second gas is made larger than the Joule-Thomson coefficient of the mixed gas by means of the gas separator.

2. The condensing device according to claim 1, wherein the condensing device further comprises at least one reactor that is disposed on the upstream side of the gas separator in the direction of supply of the mixed gas to the gas separator, the reactor is supplied with a raw material gas containing carbon oxide and hydrogen, and the reactor is capable of discharging a mixed gas containing a fuel gas that is a reaction product of carbon oxide and hydrogen, and the raw material gas that remains unreacted.

3. The condensing device according to claim 2, wherein the gas separator is capable of separating the mixed gas supplied from the reactor into a first gas containing hydrogen as a main component and a second gas containing the fuel gas.

4. The condensing device according to claim 2, wherein the condensing device further comprises a return line that returns a gas component that remains in a gaseous state even after the pressure reduction and the cooling of the second gas to the reactor.

5. The condensing device according to claim 3, wherein the condensing device further comprises a gas-liquid separator that is disposed on the downstream side of the gas separator in the direction of discharge of the second gas from the gas separator, and the gas-liquid separator is capable of separating a liquid fuel condensed by the pressure reduction and the cooling in the second gas from a gas component that remains in a gaseous state even after the pressure reduction and the cooling in the second gas.

6. The condensing device according to any one of claims 2 to 5, wherein the reactor is a membrane reactor.

7. The condensing device according to any one of claims 1 to 5, wherein the Joule-Thomson coefficient of the second gas is 15.9 K / MPa or less.

8. The condensing device according to any one of claims 1 to 5, wherein the liquid fuel contains an alcohol as a main component. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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