Liquid fuel manufacturing system and liquid fuel manufacturing method

Abstract

The main purpose of the present invention is to alleviate restrictions on the installation location of a carbon dioxide recovery system and / or to stably secure a CO2 supply source and / or cooling energy in a liquid fuel production system. According to one embodiment of the present invention, a liquid fuel production system is provided with: a gas adsorption / desorption unit that adsorbs a predetermined gas A and desorbs the gas A by heating; a heat transfer medium supply unit for supplying a heat transfer medium for heating the gas adsorption / desorption unit to the gas adsorption / desorption unit; and a liquid fuel synthesis unit that has a first gas flow path that accommodates a catalyst that advances a conversion reaction for converting a liquid fuel from a starting material gas containing at least carbon dioxide and hydrogen gas, and a second gas flow path that accommodates a catalyst that advances a conversion reaction for converting the liquid fuel from a starting material gas containing at least carbon dioxide and hydrogen gas. A second gas flow path through which a temperature adjustment gas for adjusting the temperature of the first gas flow path flows, a first outflow gas flowing out of the first gas flow path, and a second outflow gas flowing out of the second gas flow path; and a heat exchanger that exchanges heat between the second effluent gas and the heat transfer medium and heats the heat transfer medium, the second effluent gas containing a condensable gas.

Description

Technical Field

[0001] The invention relates to a liquid fuel production system and a liquid fuel production method. Background Art

[0002] In recent years, in order to reduce the environmental burden, efforts have been made to separate and recover carbon dioxide (CO2) contained in the atmosphere and various emission sources. For example, Patent Document 1 discloses a carbon dioxide recovery system that allows CO2 to be adsorbed on a carbon dioxide adsorbent and then desorbed by heating, thereby separating and recovering CO2.

[0003] In addition, in order to achieve a carbon-neutral society, a scheme has been proposed to obtain CO2 as a carbon resource and convert it into a liquid fuel that is useful as an industrial base raw material. For example, Patent Document 2 discloses a liquid fuel synthesis system that uses a membrane reactor including a catalyst and a water vapor separation membrane to perform a conversion reaction of a raw gas containing CO2 and hydrogen (H2) into methanol.

[0004] Prior art literature Patent Literature Patent Document 1: International Publication No. 2013 / 119929 Patent Document 2: Japanese Patent Application Publication No. 2018-8940 Summary of the invention Technical problem to be solved by the invention The carbon dioxide recovery system that recovers CO2 by adsorption and desorption requires a heat source when desorbing CO2. Therefore, there are constraints such as selecting a location with a heat source such as geothermal energy as the installation site, and the area where it can be used is limited.

[0005] On the other hand, in a carbon-neutral liquid fuel synthesis system, in addition to hydrogen based on water electrolysis, a stable CO2 supply source must be ensured as a raw material. In addition, in a liquid fuel synthesis system, a large amount of energy is required for cooling the generated liquid fuel gas and condensable by-product gas for liquefaction and recovery.

[0006] The main purpose of the present invention is to alleviate the constraints on the installation site of the carbon dioxide recovery system and / or to stably ensure the CO2 supply source and / or cooling energy in the liquid fuel production system.

[0007] Technical solutions for solving technical problems [1] According to an embodiment of the present invention, a liquid fuel production system comprises: a gas adsorption and desorption section, which adsorbs a given gas A and desorbs the gas A by heating; a heat transfer medium supply section, which supplies the heat transfer medium for heating the gas adsorption and desorption section to the gas adsorption and desorption section; a liquid fuel synthesis section, which has a first gas flow path and a second gas flow path, the first gas flow path accommodating a catalyst, the catalyst promoting a conversion reaction from a raw gas containing at least carbon dioxide and hydrogen to a liquid fuel, the second gas flow path circulating a temperature regulating gas for adjusting the temperature of the first gas flow path, a first outflow gas flowing out of the first gas flow path, a second outflow gas flowing out of the second gas flow path, and a heat exchanger, which performs heat exchange between the second outflow gas and the heat transfer medium to heat the heat transfer medium, the second outflow gas containing a condensable gas.

[0008] [2] In the liquid fuel production system described in [1] above, the gas adsorption and desorption section may be a carbon dioxide adsorption and desorption section, and the liquid fuel production system may include a carbon dioxide recovery section, which has the carbon dioxide adsorption and desorption section and recovers carbon dioxide concentrated gas from the carbon dioxide-containing gas.

[0009] [3] In the liquid fuel production system described in [2] above, the heat transfer medium may contain the carbon dioxide concentrated gas.

[0010] [4] In the liquid fuel production system described in any one of [1] to [3] above, the liquid fuel synthesis unit may include a water vapor separation membrane between the first gas flow path and the second gas flow path that allows water vapor to pass through, and the second outflowing gas may contain water vapor as a by-product of the conversion reaction that passes through the water vapor separation membrane and permeates from the first gas flow path to the second gas flow path.

[0011] [5] In the liquid fuel production system described in any one of [1] to [3] above, the liquid fuel synthesis unit may have a liquid fuel separation membrane between the first gas flow path and the second gas flow path that allows at least the liquid fuel to pass through, and the second outflow gas may contain the liquid fuel that has passed through the liquid fuel separation membrane and passed through from the first gas flow path to the second gas flow path.

[0012] [6] In the liquid fuel production system described in any one of [1] to [5] above, the temperature control gas may contain at least one selected from hydrogen, carbon dioxide, carbon monoxide, nitrogen and oxygen as a main component.

[0013] [7] In the liquid fuel production system described in any one of [2] to [6] above, the temperature controlling gas may contain the carbon dioxide concentrated gas, and the liquid fuel production system may include a temperature controlling gas circulation unit, which recovers the temperature controlling gas from the liquid fuel synthesis unit and supplies the carbon dioxide derived from the carbon dioxide concentrated gas to the liquid fuel synthesis unit.

[0014] [8] In the liquid fuel production system described in any one of [2] to [7] above, the carbon dioxide concentrated gas may be supplied from the carbon dioxide recovery unit to the liquid fuel synthesis unit as a constituent component of the raw gas.

[0015] [9] A method for producing a liquid fuel according to an embodiment of the present invention includes: a step (I) of bringing a gas containing carbon dioxide into contact with a carbon dioxide adsorbent, thereby adsorbing the carbon dioxide on the carbon dioxide adsorbent; a step (II) of desorbing the carbon dioxide from the carbon dioxide adsorbent by heating, thereby recovering a carbon dioxide concentrated gas; a step (III) of performing a reforming reaction using a liquid fuel synthesis unit, the liquid fuel synthesis unit having a first gas flow path and a second gas flow path, the first gas flow path containing a catalyst that promotes the reforming reaction of converting a raw gas containing at least carbon dioxide and hydrogen into a liquid fuel, the second gas flow path allowing a temperature regulating gas that regulates the temperature of the first gas flow path to flow, a first outflow gas flowing out of the first gas flow path, and a second outflow gas flowing out of the second gas flow path; and a step (IV) of heating a heat transfer medium used for heating the carbon dioxide adsorbent in the step (II) by heat exchange using the second outflow gas as a heat medium, the second outflow gas containing a condensable gas.

[0016]

[10] In the method for producing a liquid fuel described in [9] above, the temperature control gas may contain at least one selected from hydrogen, carbon dioxide, carbon monoxide, nitrogen and oxygen as a main component.

[0017]

[11] In the method for producing liquid fuel described in [9] or

[10] above, the temperature regulating gas may contain the carbon dioxide concentrated gas, and the carbon dioxide derived from the carbon dioxide concentrated gas may be recovered from the second outflow gas and used as a constituent component of the raw gas.

[0018]

[12] In the method for producing a liquid fuel according to any one of [9] to

[11] above, the heat transfer medium may contain the carbon dioxide concentrated gas.

[0019]

[13] In the method for producing liquid fuel described in any one of [9] to

[12] above, the liquid fuel synthesis unit may include a water vapor separation membrane that allows water vapor to pass between the first gas flow path and the second gas flow path, and the second outflow gas may contain water vapor as a by-product of the conversion reaction that passes through the water vapor separation membrane and passes from the first gas flow path to the second gas flow path.

[0020]

[14] In the method for manufacturing liquid fuel described in any one of [9] to

[12] above, the liquid fuel synthesis unit may have a liquid fuel separation membrane between the first gas flow path and the second gas flow path that allows at least the liquid fuel to pass through, and the second outflow gas may contain the liquid fuel that has passed through the liquid fuel separation membrane and passed through from the first gas flow path to the second gas flow path.

[0021] Effects of the Invention According to the liquid fuel manufacturing system of an embodiment of the present invention, the gas containing condensable gas flowing out of the liquid fuel synthesis unit can be used as a heat source for gas A (such as CO2) separation. As a result, the cooling energy used to liquefy the condensable gas can be reduced. In addition, in the case where gas A is CO2, a heat source for CO2 separation can be ensured, thereby alleviating the constraints on the location of the carbon dioxide recovery system (carbon dioxide recovery unit). Moreover, by using the CO2 recovered by the carbon dioxide recovery system as a raw material for liquid fuel synthesis, a CO2 source for liquid fuel synthesis can be ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1A It is a schematic configuration diagram of a liquid fuel production system according to one embodiment of the present invention.

[0023] Figure 1B It is a schematic configuration diagram of a liquid fuel production system according to another embodiment of the present invention.

[0024] Figure 2 It is a schematic configuration diagram of an example of a carbon dioxide adsorption and desorption unit used in a liquid fuel production system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] Hereinafter, the embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited to these embodiments. In addition, in order to make the description clearer, the accompanying drawings schematically show the width, thickness, shape, etc. of each part compared with the embodiments, but this is only an example and does not limit the interpretation of the present invention.

[0026] A. Liquid Fuel Manufacturing System Figure 1AIt is a schematic configuration diagram of a liquid fuel production system according to one embodiment of the present invention.

[0027] Figure 1A The liquid fuel production system 1A shown includes: A gas adsorption and desorption section 10a, which adsorbs a given gas A and desorbs the gas A by heating; a heat transfer medium supplying unit 50 for supplying a heat transfer medium for heating the gas adsorption and desorption unit 10a to the gas adsorption and desorption unit 10a; a liquid fuel synthesis unit 20 having a first gas flow path 20A and a second gas flow path 20B, wherein the first gas flow path 20A contains a catalyst that promotes a conversion reaction from a raw gas containing at least carbon dioxide and hydrogen to a liquid fuel, and the second gas flow path 20B allows a temperature-adjusting gas that adjusts the temperature of the first gas flow path 20A to flow, a first outflow gas flows out from the first gas flow path 20A, and a second outflow gas containing the temperature-adjusting gas flows out from the second gas flow path 20B; and The heat exchanger 60 performs heat exchange between the second outflow gas and the heat medium to heat the heat medium, wherein the second outflow gas contains condensable gas.

[0028] According to the liquid fuel production system 1A, the second outflow gas flowing out of the liquid fuel synthesis unit 20 is used as a heat source for desorption of gas A in the gas adsorption and desorption unit 10a. Specifically, the second outflow gas flowing out of the liquid fuel synthesis unit 20 is used as a heat source, and the heat transfer medium for heating the gas adsorption and desorption unit 10a is heated by heat exchange. Therefore, as the gas adsorption and desorption unit 10a, by applying a carbon dioxide adsorption and desorption unit that adsorbs CO2 and desorbs it by heating, it is possible to ensure a heat source for CO2 desorption, and it is possible to ease the restrictions on the installation site of the carbon dioxide recovery system (carbon dioxide recovery unit). In addition, it is possible to reduce the cooling energy for liquefying the condensable gas (for example, liquid fuel or water vapor) flowing out of the liquid fuel synthesis unit 20. Here, the second outflow gas containing the condensable gas can prevent the temperature from being significantly reduced by condensing the condensable gas during heat exchange, and functions as an efficient heat medium. As a heat transfer medium for heating the above-mentioned gas adsorption and desorption unit 10a, as described later, in addition to the CO2 concentrated gas, water (water vapor) can also be used. These may be used alone or in combination.

[0029] In addition, for example, by supplying the CO 2 concentrated gas recovered by the carbon dioxide recovery unit to the liquid fuel synthesis unit 20 as a constituent component of the raw gas, it is possible to ensure a CO 2 source for liquid fuel production.

[0030] In this specification, liquid fuel refers to a fuel that is in a liquid state at room temperature and pressure, or a fuel that can be liquefied under room temperature and pressure. Examples of fuels that are in a liquid state at room temperature and pressure include methanol, ethanol, n H 2（m－2n） (m is an integer less than 90, n is an integer less than 30), and mixtures thereof. Examples of the fuel that can be liquefied under normal temperature and pressure include propane, butane, and mixtures thereof.

[0031] In the liquid fuel manufacturing system 1A, a gas containing a gas A including a given gas A is supplied from the gas containing gas supply unit 70 to the gas adsorption and desorption unit 10a. In addition, a raw gas for synthesizing liquid fuel is supplied from the raw gas supply unit 90 to the first gas flow path 20A of the liquid fuel synthesis unit 20, and a conversion reaction is performed by a catalyst accommodated in the first gas flow path 20A in a manner capable of contacting the raw gas.

[0032] For example, the conversion reaction for synthesizing methanol by catalytic hydrogenation of a raw material gas containing CO 2 and hydrogen in the presence of a catalyst is represented by the following reaction formula (1).

[0033] The above reaction is a balanced reaction. In order to improve both the conversion rate and the reaction rate, it is preferably reacted at a high temperature and high pressure (e.g., 180°C or higher, 1 MPa or higher). The liquid fuel and water as a by-product are in a gaseous state at the time of synthesis, and remain in a gaseous state at least until flowing out of the liquid fuel synthesis unit 20.

[0034] In one embodiment, the partition wall 23 between the first gas flow path 20A and the second gas flow path 20B of the liquid fuel synthesis unit 20 includes a water vapor separation membrane that allows water vapor to pass through, thereby allowing water vapor, which is a byproduct of the reforming reaction, to flow from the first gas flow path 20A into the second gas flow path 20B. It should be noted that the water vapor separation membrane will be described later.

[0035] The temperature control gas is supplied to the second gas flow path 20B from the temperature control gas supply unit 30. The temperature control gas is a gas that adjusts the temperature of the first gas flow path 20A, for example, a cooling medium that cools the first gas flow path 20A. In the present embodiment, the temperature control gas also functions as a purge gas for purging water vapor flowing into the second gas flow path 20B.

[0036] The water vapor flowing into the second gas flow path 20B flows out from the liquid fuel synthesis unit 20 to the second outflow gas recovery pipe 41 together with the temperature control gas as the second outflow gas. The second outflow gas exchanges heat with the heat transfer medium supplied from the heat transfer medium supply unit 50 in the heat exchanger 60, whereby the heat transfer medium is heated to heat the gas adsorption and desorption unit 10a to a given temperature (a temperature at which the gas A can be desorbed), and the water vapor contained in the second outflow gas is condensed and recovered from the drain trap 42 and the liquefied product recovery pipe 43.

[0037] On the other hand, the gas that has not passed through the water vapor separation membrane, typically liquid fuel, unreacted raw material gas (residual raw material gas), etc., flows out from the first gas flow path 20A as the first outflow gas. The liquid fuel is recovered from the first outflow gas, and the residual raw material gas is reused as the raw material gas as needed.

[0038] In another embodiment, the partition wall 23 between the first gas flow path 20A and the second gas flow path 20B of the liquid fuel synthesis unit 20 includes a liquid fuel separation membrane that allows the liquid fuel to pass through, thereby, the liquid fuel as the target product of the conversion reaction flows from the first gas flow path 20A into the second gas flow path 20B. As the liquid fuel separation membrane, for example, the liquid fuel separation membrane described in Japanese Patent Publication No. 2020-23488 can be used. It should be noted that the liquid fuel separation membrane allows the liquid fuel to pass through with a higher selectivity than water vapor, and does not completely separate the two.

[0039] The temperature controlling gas is supplied from the temperature controlling gas supply unit 30 to the second gas flow path 20B, and the temperature controlling gas also functions as a purge gas for purging the liquid fuel flowing into the second gas flow path 20B.

[0040] The liquid fuel flowing into the second gas flow path 20B flows out from the liquid fuel synthesis unit 20 to the second outflow gas recovery pipe 41 together with the temperature control gas as the second outflow gas. The second outflow gas exchanges heat with the heat transfer medium supplied from the heat transfer medium supply unit 50 in the heat exchanger 60, whereby the heat transfer medium is heated to heat the gas adsorption and desorption unit 10a to a given temperature (a temperature at which the gas A can be desorbed), and the liquid fuel contained in the second outflow gas is condensed and recovered from the drain trap 42 and the liquefied product recovery pipe 43.

[0041] On the other hand, the gas that has not passed through the liquid fuel separation membrane, typically water vapor, unreacted raw gas (residual raw gas), etc., flows out from the first gas flow path 20A as the first outflow gas. Water and the residual raw gas are separated from the first outflow gas as needed, and the residual raw gas is reused as the raw gas.

[0042] In another embodiment, the partition wall 23 between the first gas flow path 20A and the second gas flow path 20B of the liquid fuel synthesis unit 20 is a non-permeable partition wall that does not allow gas to pass through. In this embodiment, the temperature-controlled gas containing condensable gas is supplied to the second gas flow path 20B. The first outflow gas containing liquid fuel, water vapor and residual raw gas flows out from the first gas flow path 20A, and the temperature-controlled gas flows out from the second gas flow path 20B as the second outflow gas. The second outflow gas exchanges heat with the heat transfer medium supplied by the heat transfer medium supply unit 50 in the heat exchanger 60, whereby the heat transfer medium is heated to be able to heat the gas adsorption and desorption unit 10a to a given temperature (a temperature at which gas A can be desorbed), and the condensable gas contained in the second outflow gas is condensed and recovered from the drain trap 42 and the liquefied product recovery pipe 43. As the condensable gas, water vapor or the like can be used.

[0043] It should be noted that, in the example shown in the figure, the first gas flow path 20A and the second gas flow path 20B are divided into upper and lower parts by the partition wall 23, but the second gas flow path 20B only needs to be configured to be able to adjust the temperature of the first gas flow path 20A. For example, the liquid fuel synthesis unit 20 has a double tube structure, and one of the inner tube and the outer tube can be used as the first gas flow path, and the other can be used as the second gas flow path.

[0044] In one embodiment, the temperature control gas contains at least one selected from hydrogen, carbon dioxide, carbon monoxide, nitrogen, and oxygen as a main component. Here, "containing as a main component" means containing at the highest content rate.

[0045] A-1. Example of a liquid fuel production system As an example of an embodiment in which the liquid fuel synthesis unit 20 has a water vapor separation membrane between the first gas flow path 20A and the second gas flow path 20B, Figure 1B The liquid fuel manufacturing system 1B shown in FIG. 1 is described. It should be noted that the liquid fuel manufacturing system 1B includes a liquid fuel synthesis unit having a water vapor separation membrane, and the temperature-adjusting gas supplied to the liquid fuel synthesis unit can also function as a purge gas. Therefore, in the following description, the temperature-adjusting gas is sometimes referred to as a purge gas.

[0046] Figure 1B The liquid fuel production system 1B shown has: A carbon dioxide recovery unit 10, which recovers CO2 concentrated gas from the CO2-containing gas, the carbon dioxide recovery unit 10 includes a carbon dioxide adsorption and desorption unit 10a, the carbon dioxide adsorption and desorption unit 10a adsorbs CO2 and desorbs CO2 by heating; The liquid fuel synthesis unit 20 includes a first gas flow path 20A and a second gas flow path 20B, wherein the first gas flow path 20A contains a catalyst that promotes a conversion reaction from a raw gas containing at least CO2 and hydrogen to a liquid fuel, and the second gas flow path 20B allows a purge gas for adjusting the temperature of the first gas flow path 20A to flow, a first outflow gas flows out from the first gas flow path 20A, and a second outflow gas flows out from the second gas flow path 20B; a raw gas supply unit 90 for supplying the raw gas to the liquid fuel synthesis unit 20; a purge gas supply unit 30 for supplying the CO2 concentrated gas as a constituent of the purge gas to the liquid fuel synthesis unit 20; a purge gas circulation unit 40 for recovering the purge gas from the liquid fuel synthesis unit 20 and supplying CO 2 derived from the CO 2 concentrated gas to the raw gas supply unit 90; a heat transfer medium supplying unit 50 for supplying the CO 2 concentrated gas as a heat transfer medium for heating the carbon dioxide adsorbent to the carbon dioxide adsorption and desorption unit 10 a ; and The heat exchanger 60 performs heat exchange between the second outflow gas and the heat transfer medium to heat the heat transfer medium. The CO 2 -containing gas is supplied from the carbon dioxide-containing gas supply unit 70 to the carbon dioxide recovery unit 10 .

[0047] Hereinafter, each component will be described in more detail with reference to the liquid fuel production system 1B.

[0048] A-1-1. Carbon dioxide recovery department The carbon dioxide recovery unit 10 has a carbon dioxide adsorption and desorption unit 10a. The carbon dioxide recovery unit 10 may also have a pump, a carbon dioxide concentrated gas storage unit, etc. The carbon dioxide adsorption and desorption unit 10a, for example, accommodates a carbon dioxide adsorbent material, which adsorbs CO2 by contacting with a gas containing CO2, and desorbs CO2 by heating. By having such a structure, the carbon dioxide recovery unit 10 supplies a gas containing CO2 to the carbon dioxide adsorption and desorption unit 10a so that CO2 is adsorbed on the carbon dioxide adsorbent material, and then desorbs CO2 by heating the carbon dioxide adsorbent material. By sucking the desorbed CO2 with a pump, the CO2 concentrated gas containing CO2 can be recovered at a higher concentration than the CO2-containing gas supplied to the carbon dioxide adsorption and desorption unit 10a.

[0049] The carbon dioxide adsorption and desorption section 10a has, for example, a structure in which gas can flow in and out, and the carbon dioxide adsorbent is arranged in a manner that allows contact with the CO2-containing gas flowing in. The carbon dioxide adsorbent is preferably carried on any appropriate substrate. In one embodiment, the carbon dioxide adsorption and desorption section 10a includes a substrate, and a carbon dioxide adsorption layer arranged on the surface of the substrate and containing the carbon dioxide adsorbent.

[0050] The structure of the substrate is not particularly limited, and examples thereof include a monolithic shape, a filter structure such as a filter cloth, a particle structure, and the like. The so-called monolithic shape refers to a shape having a plurality of compartments that are connected in the length direction, and is a concept that includes a honeycomb shape. In one embodiment, the substrate is a honeycomb substrate having a plurality of compartments. As the cross-sectional shape of the compartment (the cross-sectional shape in a direction orthogonal to the length direction of the honeycomb substrate), for example, a triangle, a quadrilateral, a pentagon, a polygonal shape higher than a hexagon, a circle, and an ellipse can be cited.

[0051] In one embodiment, if Figure 2 As shown, the carbon dioxide adsorption and desorption section 10a comprises: a honeycomb substrate 11 having a plurality of cells 11b defined by partition walls 11a; and a carbon dioxide adsorption layer 13 formed on the inner surface of the cells 11b (in other words, the surface of the partition walls 11a). The cross-sectional shape of the cells in the honeycomb substrate of the example in the figure is a quadrilateral, and a gas containing CO2 is supplied to the space in the cross-section where the carbon dioxide adsorption layer 13 is not formed.

[0052] As a material constituting the substrate, ceramics can be cited representatively. As ceramics, for example, silicon carbide, silicon-silicon carbide composite materials, cordierite, mullite, aluminum oxide, silicon nitride, spinel, silicon carbide-cordierite composite materials, lithium aluminosilicate, and aluminum titanate can be cited. The materials constituting the substrate can be used alone or in combination.

[0053] The carbon dioxide adsorption layer is not particularly limited as long as it is arranged on the surface of the substrate in a manner that allows contact with the gas containing CO 2 . The carbon dioxide adsorption layer may substantially only include a carbon dioxide adsorbent, or may include other components (such as a porous carrier) other than the carbon dioxide adsorbent.

[0054] As the carbon dioxide adsorbent, any appropriate compound that can adsorb and desorb CO2 can be used. Examples of the carbon dioxide adsorbent include: nitrogen-containing compounds described below; alkaline compounds such as sodium hydroxide and potassium hydroxide; carbonates such as calcium carbonate and potassium carbonate; bicarbonates such as calcium hydrogen carbonate and potassium hydrogen carbonate; organometallic structures (MOFs) such as MOF-74, MOF-200, and MOF-210; zeolite; activated carbon; nitrogen-doped carbon; ionic liquids, etc.

[0055] Among the carbon dioxide adsorbents, nitrogen-containing compounds are more preferably used. More specifically, nitrogen-containing compounds include: amine compounds such as monoethanolamine, diethanolamine, triethanolamine, N-(3-aminopropyl)diethanolamine, aminopropyltrimethoxysilane, and polyethyleneamine; imine compounds such as polyethyleneimine and polyethyleneimine-trimethoxysilane; amide compounds such as polyamideamine; piperazine compounds such as 1-(2-hydroxyethyl)piperazine; aminosilane coupling agents such as 3-aminopropyltriethoxysilane and N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane. The carbon dioxide adsorbent can be used alone or in combination.

[0056] The carbon dioxide adsorption layer can be produced, for example, by the following method. First, a carbon dioxide adsorption layer forming liquid is prepared by dissolving or dispersing a carbon dioxide adsorbent and any other components in a solvent. Examples of the solvent include water, alcohols, glycols, and combinations thereof. Next, after the carbon dioxide adsorption layer forming liquid is applied to the substrate, the coating is dried and sintered as needed to form a carbon dioxide adsorption layer.

[0057] A-1-2. Liquid fuel synthesis department The liquid fuel synthesis unit 20 is a so-called membrane reactor for converting raw gas into liquid fuel. The shape of the liquid fuel synthesis unit 20 is not particularly limited, and can be, for example, a monolithic shape, a flat plate shape, a tube shape, a cylinder shape, a column shape, a polygonal column shape, or the like.

[0058] The liquid fuel synthesis section 20 has a catalyst 22, a steam separation membrane 24, a non-permeable side space 20A, and a permeable side space 20B. The catalyst 22 promotes the conversion reaction of the raw gas containing at least CO2 and hydrogen into liquid fuel. The liquid fuel synthesis section 20 is provided with a first supply port s1 and a first discharge port d1 communicated via the non-permeable side space 20A, and a second supply port s2 and a second discharge port d2 communicated via the permeable side space 20B.

[0059] The non-permeable side space 20A is a space on the non-permeable side of the water vapor separation membrane 24. The raw gas is supplied to the non-permeable side space 20A from the raw gas supply unit 90 via the first supply port s1. The liquid fuel synthesized in the catalyst 22 and the remaining raw gas flow out from the non-permeable side space 20A to the first outflow gas recovery unit 80 via the first discharge port d1 as the first outflow gas. That is, the non-permeable side space 20A is a first gas flow path.

[0060] The permeation side space 20B is a space on the permeation side of the water vapor separation membrane 24. As described later, water vapor and part of hydrogen in the raw gas permeate the water vapor separation membrane 24, so that water vapor and hydrogen flow into the permeation side space 20B. In addition, the purge gas is supplied to the permeation side space 20B from the purge gas supply unit 30 via the second supply port s2. Water vapor, hydrogen and purge gas flow out from the permeation side space 20B to the purge gas circulation unit 40 via the second discharge port d2 as the second outflow gas. That is, the permeation side space 20B is a second gas flow path.

[0061] The catalyst 22 promotes the conversion reaction from the raw gas to the liquid fuel. The catalyst is arranged in the non-permeable side space 20A. The catalyst is preferably filled in the non-permeable side space 20A, but can also be arranged on the surface of the water vapor separation membrane 24 in a layered or island shape. In the case where the catalyst is in a particle shape as shown in the example, the particle size (diameter) of the catalyst particles can be set to, for example, 0.5 mm or more and 10 mm or less. The catalyst particles can be composed of only the catalyst, or can be a structure in which the catalyst is supported on the carrier particles. The carrier particles are preferably porous particles.

[0062] As the catalyst, any catalyst suitable for the conversion reaction to the desired liquid fuel can be used. Specifically, metal catalysts (copper, palladium, etc.), oxide catalysts (zinc oxide, zirconium oxide, gallium oxide, etc.), and composite catalysts thereof (copper-zinc oxide, copper-zinc oxide-alumina, copper-zinc oxide-chromium oxide-alumina, copper-cobalt-titanium dioxide, and catalysts modified with palladium thereof, etc.) can be used.

[0063] The water vapor separation membrane 24 allows water vapor, which is a byproduct of the conversion reaction from the raw material gas to the liquid fuel, to pass through, thereby shifting the reaction equilibrium of the above formula (1) to the product side by utilizing the equilibrium shift effect.

[0064] The molecular diameter of water (0.26 nm) is close to the molecular diameter of hydrogen (0.296 nm), so that not only water vapor as a byproduct of the reforming reaction but also a part of hydrogen contained in the raw material gas can permeate the water vapor separation membrane 24 .

[0065] The water vapor separation membrane 24 preferably has a thermal conductivity of 100 nmol / (s·Pa·m 2 ) or more. The water vapor permeability coefficient can be obtained by a known method (see Ind. Eng. Chem. Res., 40, 163-175 (2001)).

[0066] The water vapor separation membrane 24 preferably has a separation factor of 100 or more. The larger the separation factor, the easier it is for water vapor to pass through, and the harder it is for components other than water vapor (hydrogen, carbon dioxide, and liquid fuel, etc.) to pass through. The separation factor can be obtained by a known method (see Fig. 1 of "Separation and Purification Technology 239 (2020) 116533").

[0067] As the water vapor separation membrane 24, any appropriate water vapor separation membrane can be used. In one embodiment, an inorganic membrane can be used as the water vapor separation membrane 24. Inorganic membranes have heat resistance, pressure resistance, water vapor resistance, etc., so they are preferred. As inorganic membranes, zeolite membranes, silica membranes, alumina membranes, and composite membranes thereof can be cited. For example, an LTA-type zeolite membrane having a molar ratio (Si / Al) of silicon element (Si) to aluminum element (Al) of 1.0 or more and 3.0 or less has excellent water vapor permeability, so it is preferred.

[0068] The zeolite membrane used as the water vapor separation membrane 24 can be obtained by the production method described in Japanese Patent Application Publication No. 2004-66188. The silicon dioxide membrane used as the water vapor separation membrane 24 can be obtained by the production method described in International Publication No. 2008 / 050812.

[0069] In the example shown in the figure, the water vapor separation membrane 24 is supported by a porous support 26 .

[0070] The porous support 26 is made of a porous material. As the porous material, ceramic materials, metal materials, resin materials, etc. can be used, and ceramic materials are particularly preferred. As the aggregate of the ceramic material, alumina (Al2O3), titanium dioxide (TiO2), mullite (Al2O3·SiO2), ceramic particles, and cordierite (Mg2Al4Si5O 18 ), etc., and aluminum oxide is preferred in consideration of availability, clay stability, and corrosion resistance. As an inorganic binder for the ceramic material, at least one of titanium dioxide, mullite, easily sintered aluminum oxide, silicon dioxide, glass frit, clay mineral, and easily sintered cordierite can be used. The ceramic material may not include an inorganic binder.

[0071] The average pore size of the porous support can be set to be greater than 5 μm and less than 25 μm. The average pore size of the porous support can be measured by mercury intrusion. The porosity of the porous support can be set to be greater than 25% and less than 50%. The average particle size of the porous material constituting the porous support can be set to be greater than 1 μm and less than 100 μm. In this embodiment, the average particle size refers to the arithmetic mean of the maximum diameters of 30 particles of the measurement object (randomly selected) measured by cross-sectional microstructure observation using a SEM (Scanning Electron Microscope).

[0072] A-1-3. Carbon dioxide-containing gas supply unit The carbon dioxide-containing gas supply unit 70 optionally includes a blower or the like, and supplies a CO 2 -containing gas from the atmosphere or various equipment such as factories and commercial facilities to the carbon dioxide recovery unit 10 (more specifically, the carbon dioxide adsorption and desorption unit 10 a ).

[0073] A-1-4. Purge gas supply unit The purge gas supply unit 30 is configured to supply CO2 concentrated gas as a constituent component of the purge gas from the carbon dioxide recovery unit 10 to the liquid fuel synthesis unit 20. The purge gas supply unit 30 includes a carbon dioxide concentrated gas supply pipe 32, a hydrogen supply pipe 34, and a hydrogen generator 36. One end of the carbon dioxide concentrated gas supply pipe 32 is connected to the carbon dioxide recovery unit 10, and the other end is connected to the second supply port s2 of the liquid fuel synthesis unit 20. One end of the hydrogen supply pipe 34 is connected to the hydrogen generator 36, and the other end is connected to the carbon dioxide concentrated gas supply pipe 32. The hydrogen generator 36 is, for example, a hydrogen manufacturing device using water electrolysis technology. The CO2 concentrated gas supplied from the carbon dioxide recovery unit 10 to the liquid fuel synthesis unit 20 via the carbon dioxide concentrated gas supply pipe 32 is mixed with the hydrogen supplied from the hydrogen generator 36, thereby generating a purge gas containing CO2 concentrated gas and hydrogen. The purge gas is heated to a desired temperature (for example, 150° C. or higher and 350° C. or lower), and then supplied to the second supply port s2 of the liquid fuel synthesizing unit 20 .

[0074] In one embodiment, the purge gas contains hydrogen as a main component. Here, “containing hydrogen as a main component” means that the content rate of hydrogen is the highest among the gases contained in the purge gas.

[0075] The CO2 concentration in the purge gas is, for example, 10% by volume or more and 40% by volume or less, preferably 20% by volume or more and 30% by volume or less. The hydrogen concentration in the purge gas is, for example, 60% by volume or more and 90% by volume or less, preferably 70% by volume or more and 80% by volume or less. By making the purge gas contain CO2 and hydrogen in the above ratio, the gas (remaining raw gas and purge gas) recovered from the liquid fuel synthesis unit can be appropriately recycled as raw gas.

[0076] A-1-5. Purge gas circulation unit, heat transfer medium supply unit, and heat exchanger The purge gas circulation unit 40 includes a second outflow gas recovery pipe 41, a drain trap 42, a liquefied product recovery pipe 43, and a recovery gas supply pipe 44. One end of the second outflow gas recovery pipe 41 is connected to the second outlet d2 of the liquid fuel synthesis unit 20, and the other end is connected to the drain trap 42. The second outflow gas containing water vapor and hydrogen gas and the purge gas that have passed through the water vapor separation membrane 24 flows into the second outflow gas recovery pipe 41 from the second outlet d2.

[0077] The heat transfer medium supply unit 50 has a heat transfer medium supply piping 52, which supplies the CO2 concentrated gas recovered by the carbon dioxide recovery unit 10 to the carbon dioxide adsorption and desorption unit 10a as a heat transfer medium for heating the carbon dioxide adsorbent material. The CO2 concentrated gas recovered to the carbon dioxide recovery unit 10 is supplied to the carbon dioxide adsorption and desorption unit 10a again via the heat transfer medium supply piping 52, and by recovering the desorbed CO2, it is recovered to the carbon dioxide recovery unit 10 again as a CO2 concentrated gas containing CO2 at a higher concentration than the CO2 concentrated gas supplied as the heat transfer medium. Specifically, the CO2 concentrated gas as the heat transfer medium circulates in the same flow path as the CO2-containing gas in the carbon dioxide adsorption and desorption unit 10a to heat the carbon dioxide adsorption and desorption material, thereby being recovered to the carbon dioxide recovery unit 10 as a higher concentration CO2 concentrated gas also containing desorbed CO2. For example, in Figure 2In the carbon dioxide adsorption and desorption section 10a shown, the space in the cross section of the cell 11b in the honeycomb substrate 11 where the carbon dioxide adsorption layer 13 is not formed can be set as a common flow path for the CO2-containing gas and the CO2 concentrated gas as the heat transfer medium. By circulating the CO2 concentrated gas in this way, the CO2 concentrated gas containing CO2 at a high concentration (for example, the CO2 concentration is 50% by volume or more) can be appropriately obtained. Not limited to the example shown in the figure, the heat transfer medium supply piping 52 can also be a structure that is connected to the carbon dioxide-containing gas supply section 70 to supply the CO2 concentrated gas to the carbon dioxide adsorption and desorption section 10a. In addition, although not shown in the figure, the heat transfer medium supply section can also have a second heat transfer medium supply piping, which supplies other heat transfer media (for example, water vapor, etc.) other than the CO2 concentrated gas to the carbon dioxide adsorption and desorption section. In this case, the second heat medium supply pipe can be configured to be connected to another heat medium storage unit, and to supply another heat medium to the carbon dioxide adsorption and desorption unit 10 a in a state heated by heat exchange with the heat exchanger 60 .

[0078] The heat exchanger 60 is disposed between the heat transfer medium supply unit 50 and the purge gas circulation unit 40. Specifically, the heat exchanger 60 includes a first flow path 62 disposed between the heat transfer medium supply pipe 52 and a second flow path 64 disposed between the second outflow gas recovery pipe 41, and is configured to be able to perform heat exchange between a first fluid flowing through the first flow path 62 and a second fluid flowing through the second flow path 64.

[0079] According to the above structure, heat exchange is performed between the heat transfer medium (specifically, CO2 concentrated gas) flowing in the first flow path 62 and the second outflow gas flowing in the second flow path 64, and the heat transfer medium is heated. In addition, during the heat exchange, by condensing condensable gases such as water vapor contained in the second outflow gas, the condensation heat can be used for heat exchange, which can contribute to further improvement of thermal efficiency.

[0080] The temperature of the heat transfer medium before heat exchange is, for example, 5°C to 100°C, preferably 10°C to 80°C. The temperature of the heat transfer medium after heat exchange is, for example, 60°C to 200°C, preferably 90°C to 160°C. The temperature of the second outflow gas before heat exchange is, for example, 150°C to 350°C, preferably 200°C to 300°C. The temperature of the second outflow gas (recovered gas) after heat exchange is, for example, 25°C to 250°C, preferably 50°C to 200°C.

[0081] The concentration of the condensable gas in the second outflow gas before heat exchange is, for example, 5 volume % or more and 50 volume % or less, preferably 10 volume % or more and 40 volume % or less. If the concentration of the condensable gas in the second outflow gas is within the above range, heat exchange can be performed with higher efficiency.

[0082] The drain trap 42 is disposed on the downstream side of the heat exchanger 60. The drain trap 42 separates the liquid (typically water) condensed in the heat exchanger 60 from the gas. The separated liquid is recovered from the liquefied product recovery pipe 43.

[0083] The gas (recovered gas) separated by the drain trap 42 contains the purge gas and the hydrogen gas that has permeated the water vapor separation membrane 24 . The recovered gas is supplied to the raw material gas supply unit 90 through the recovered gas supply pipe 44 .

[0084] A-1-6. Raw material gas supply unit The raw gas supply unit 90 has a pressurizing unit, etc., and supplies the raw gas to the liquid fuel synthesis unit 20 at a desired pressure and temperature. In the example shown in the figure, the recovered gas is supplied to the liquid fuel synthesis unit 20 as the raw gas, but the raw gas can also be prepared by further mixing the remaining raw gas recovered from the first outflow gas, hydrogen gas, carbon dioxide, or a mixed gas thereof, etc. as needed. Alternatively, the raw gas may not contain the recovered gas at all.

[0085] A-1-7. First outflow gas recovery section The first outflow gas recovery unit 80 recovers the first outflow gas flowing out from the liquid fuel synthesis unit. The first outflow gas contains condensable gas (in Figure 1B In the embodiment of the present invention, the residual raw gas is liquid fuel) and the residual raw gas. As required, the residual raw gas and the condensable gas are subjected to gas-liquid separation for the first outflow gas. As described above, the residual raw gas separated from the liquid fuel is supplied to the raw gas supply unit 90 and can be reused as a constituent component of the raw gas.

[0086] Above, refer to Figure 1BThe embodiment in which the liquid fuel synthesis unit 20 has a water vapor separation membrane between the first gas flow path 20A and the second gas flow path 20B is described, but the above description can also be applied to the embodiment in which the liquid fuel synthesis unit has a liquid fuel separation membrane between the first gas flow path and the second gas flow path. Specifically, the second outflow gas containing the liquid fuel and the purge gas that have passed through the liquid fuel separation membrane is used for heat exchange with the heat transfer medium, and it is preferred that the purge gas contains CO2 concentrated gas; the liquid (representatively liquid fuel) produced by condensation during heat exchange is separated from the gas, and the separated liquid is recovered from the liquefied product recovery pipe, and the separated gas (recovered gas including the purge gas) can be supplied to the raw gas supply unit via the recovery gas supply pipe. In addition, the first outflow gas containing water vapor and the remaining raw gas is recovered and separated from the gas and liquid in the first outflow gas recovery unit, and the remaining raw gas after separation from the water vapor is supplied to the raw gas supply unit and can be reused as a constituent component of the raw gas.

[0087] A-2. First Modification exist Figure 1B In the embodiment shown, the liquid fuel synthesis section is a membrane reactor, but is not limited to this structure. For example, the liquid fuel synthesis section can be configured to have a catalyst section and a separation section as separate reactors in order from the upstream side, the catalyst section includes a catalyst, and the separation section includes a water vapor separation membrane, a non-permeable side space, and a permeable side space. The liquid fuel gas, by-product gas (water vapor), and remaining raw gas flowing out of the catalyst section flow into the non-permeable side space of the separation section, and the by-product gas and hydrogen that have passed through the water vapor separation membrane flow out from the permeable side space of the separation section together with the purge gas as the second outflow gas. It should be noted that in Modification 1, the gas flowing out of the catalyst section directly flows into the separation section, so the non-permeable side space of the separation section is regarded as forming a first gas flow path integrally with the catalyst section, and the permeable side space of the separation section is regarded as the second gas flow path.

[0088] A-3 Second Modification exist Figure 1B In the illustrated embodiment, when the water vapor separation membrane 24 is viewed from the side, the flow directions of the raw gas and the purge gas are opposite to each other, but they may be in the same direction.

[0089] A-4 Third Modification The liquid fuel synthesis section may further include a buffer layer between the catalyst 22 and the water vapor separation membrane 24. The buffer layer is provided to prevent the catalyst contained in the catalyst 22 from directly contacting the water vapor separation membrane 24. By physically isolating the catalyst from the water vapor separation membrane 24 using the buffer layer, even if the catalyst is heated by the reaction heat, cracks generated in the water vapor separation membrane 24 starting from the contact point with the catalyst can be suppressed.

[0090] B. Methods of producing liquid fuels A method for producing a liquid fuel according to an embodiment of the present invention includes: Step (I), contacting a CO2-containing gas with a carbon dioxide adsorbent, so that the carbon dioxide is adsorbed on the carbon dioxide adsorbent; Step (II), removing the carbon dioxide from the carbon dioxide adsorbent by heating, and recovering the CO2 concentrated gas; Step (III) of performing a reforming reaction using a liquid fuel synthesis unit, the liquid fuel synthesis unit having a first gas flow path and a second gas flow path, the first gas flow path containing a catalyst that promotes the reforming reaction of converting a raw gas containing at least carbon dioxide and hydrogen into a liquid fuel, the second gas flow path allowing a temperature-adjusting gas for adjusting the temperature of the first gas flow path to flow, a first outflow gas flowing out of the first gas flow path, and a second outflow gas flowing out of the second gas flow path, and Step (IV) of heating the heat transfer medium used to heat the carbon dioxide adsorbent in the step (II) by heat exchange using the second outflow gas as a heat medium, The second outflow gas contains condensable gas.

[0091] Preferably, the heat exchange is performed using condensation heat of the condensable gas.

[0092] The method for producing liquid fuel according to the embodiment of the present invention can be suitably implemented by using the liquid fuel production system described in the section A.

[0093] In one embodiment, the temperature control gas contains at least one selected from hydrogen, carbon dioxide, carbon monoxide, nitrogen, and oxygen as a main component.

[0094] In one embodiment, the temperature-adjusting gas contains the CO 2 concentrated gas, and carbon dioxide derived from the CO 2 concentrated gas is recovered from the second outflow gas and used as a constituent component of the raw gas.

[0095] In one embodiment, the heat transfer medium contains the CO 2 concentrated gas.

[0096] B-1. Process (I) In step (I), a gas containing CO2 is brought into contact with a carbon dioxide adsorbent, and CO2 is adsorbed on the carbon dioxide adsorbent. The CO2 concentration in the CO2-containing gas is, for example, 0.01% by volume or more and 2% by volume or less. The temperature of the CO2-containing gas is, for example, 0°C or more and 40°C or less. The pressure of the CO2-containing gas is, for example, 0.3×10 5 Pa or more and 2.0×10 5 Pa or less. The relative humidity RH of the CO2-containing gas is, for example, 10% RH or more and 60% RH or less. The implementation time of step (I) is, for example, 15 minutes or more and 3 hours or less. The flow rate of the CO2-containing gas in step (I) is, for example, 0.5 m / sec or more and 5 m / sec or less.

[0097] The CO2 adsorption rate in step (I) (= (CO2 concentration in the gas before contact with the carbon dioxide adsorbent - CO2 concentration in the gas after contact with the carbon dioxide adsorbent) / CO2 concentration in the gas before contact with the carbon dioxide adsorbent × 100) is, for example, 60% or more, preferably 75% or more, more preferably 80% or more, for example 90% or less.

[0098] B-2. Step (II) In step (II), CO2 is desorbed from the carbon dioxide adsorbent by heating to recover the CO2 concentrated gas. For example, the carbon dioxide adsorbent that adsorbed CO2 in step (I) is heated to desorb CO2 from the carbon dioxide adsorbent, and the CO2 desorbed (released) from the carbon dioxide adsorbent is sucked by a pump or the like to recover the CO2 concentrated gas.

[0099] The heating temperature in step (II) is, for example, higher than 40° C., preferably 70° C. or higher, and for example, 200° C. or lower, preferably 110° C. or lower. The heating time in step (II) is, for example, 1 minute or longer and 1 hour or shorter.

[0100] The CO2 concentrated gas contains CO2 at a higher concentration than the CO2-containing gas. The CO2 concentration in the CO2 concentrated gas is, for example, 50% by volume or more, preferably 60% by volume or more, more preferably 80% by volume or more, for example, 100% by volume or less. The CO2 concentrated gas having such a CO2 concentration is suitable as a constituent component of a purge gas (ultimately a raw gas).

[0101] In one embodiment, the heating of the carbon dioxide adsorbent material is performed using a heat transfer medium containing CO2 concentrated gas, for example, CO2 concentrated gas can be used as the heat transfer medium. Specifically, the recovered CO2 concentrated gas is heated to a temperature at which the carbon dioxide adsorbent material can desorb CO2, and the CO2 concentrated gas is used to heat the carbon dioxide adsorbent material. For example, according to Figure 1B In the liquid fuel manufacturing system 1B shown, the CO2 concentrated gas flowing out of the carbon dioxide recovery unit 10 is supplied again to the carbon dioxide adsorption and desorption unit 10a which adsorbs CO2 as a heat transfer medium while being heated by the heat exchanger 60, and the desorbed CO2 is recovered to the carbon dioxide recovery unit 10 as a CO2 concentrated gas containing CO2 at a higher concentration than when it was supplied as a heat transfer medium. By repeating the circulation of the CO2 concentrated gas in this way, the CO2 concentrated gas containing CO2 at a higher concentration can be recovered.

[0102] B-3. ​​Step (III) In step (III), a liquid fuel synthesis unit is used to carry out a conversion reaction. The liquid fuel synthesis unit has a first gas flow path and a second gas flow path. The first gas flow path contains a catalyst that promotes the conversion reaction from a raw gas containing at least carbon dioxide and hydrogen to a liquid fuel. The second gas flow path allows a temperature-adjusting gas that adjusts the temperature of the first gas flow path to flow, and a first outflow gas flows out from the first gas flow path, and a second outflow gas flows out from the second gas flow path. Specifically, the raw gas is made to flow into the first gas flow path, and as shown in the above reaction formula (1), the raw gas containing CO2 and hydrogen is catalytically hydrogenated in the presence of the catalyst, thereby synthesizing methanol. In addition, the temperature-adjusting gas is made to flow into the second gas flow path.

[0103] The liquid fuel synthesis section has, for example, a separation membrane between the first gas flow path and the second gas flow path that allows the condensable gas of either the liquid fuel or the water vapor to pass through and separate from the other. As such a separation membrane, a water vapor separation membrane or a liquid fuel separation membrane can be used. In the case where the liquid fuel synthesis section has a water vapor separation membrane, a first outflow gas containing liquid fuel and a second outflow gas containing water vapor flow out of the liquid fuel synthesis section. In the case where the liquid fuel synthesis section has a liquid fuel separation membrane, a first outflow gas containing water vapor and a second outflow gas containing liquid fuel flow out of the liquid fuel synthesis section.

[0104] The CO2 concentration in the raw gas is, for example, 10% by volume or more and 40% by volume or less, preferably 20% by volume or more and 30% by volume or less. The hydrogen concentration in the raw gas is, for example, 60% by volume or more and 90% by volume or less, preferably 70% by volume or more and 80% by volume or less.

[0105] The reaction temperature of step (III) is, for example, 180° C. or more, preferably 200° C. or more and 350° C. or less. The pressure is, for example, 1 MPa or more, preferably 2 MPa or more and 6 MPa or less. The flow rate of the raw gas is appropriately adjusted according to the catalyst characteristics, reactor style, etc., and when expressed in terms of the space velocity GHSV (Gas Hourly Space Velocity) under standard conditions (0° C., 1 atmosphere), it is, for example, 1000 / h or more and 50000 / h or less, preferably 2000 / h or more and 20000 / h or less, and more preferably 3000 / h or more and 12000 / h or less.

[0106] B-4. Step (IV) In step (IV), the heat transfer medium used to heat the carbon dioxide adsorbent in step (II) is heated by heat exchange using the second outflow gas as a heat medium. By using the second outflow gas obtained in step (III) as a heat source for CO2 removal, the cooling energy for cooling the condensable gas (such as water, liquid fuel) contained in the second outflow gas can be reduced, and the constraints on the installation site of the carbon dioxide recovery system for step (I) and step (II) can be alleviated. There is no particular limitation on the heat transfer medium as long as the effect of the present invention can be obtained. For example, it is preferable to use CO2 concentrated gas.

[0107] In the above heat exchange, it is preferred to condense the condensable gas contained in the second outflow gas. Thus, the condensation heat can be used for heat exchange, and the temperature is kept constant during condensation, so that abrupt temperature changes can be prevented. Furthermore, the condensable gas contained in the second outflow gas can be easily separated from the recovery gas that may contain hydrogen, purge gas, etc.

[0108] In one embodiment, the purge gas contains CO2 concentrated gas, and the purge gas is recovered from the second effluent gas and used as a constituent of the raw gas. By using CO2 derived from the CO2 concentrated gas (in other words, CO2 derived from a gas containing CO2) as a constituent of the raw gas, it is possible to contribute to the synthesis of a carbon-neutral liquid fuel. The purge gas preferably contains hydrogen as a main component. Thus, the gas recovered from the second effluent gas can be reused as part of the raw gas without further separation operations.

[0109] The liquid fuel or water and the remaining raw gas are separated and recovered from the first outflow gas, and the remaining raw gas is reused as a part of the raw gas in step (III).

[0110] Regarding the reactor, catalyst, water vapor separation membrane, liquid fuel separation membrane and purge gas for generating liquid fuel, as described in item A.

[0111] Industrial Applicability The liquid fuel production system and the liquid fuel production method according to the embodiment of the present invention can be applied to the production of liquid fuels such as methanol.

[0112] Description of Reference Numerals 1A, 1B Liquid fuel production system 10 Carbon dioxide recovery unit 20 Liquid Fuel Synthesis Department 30 Temperature control gas supply unit (purge gas supply unit) 40 Temperature control gas circulation section (purge gas circulation section) 50 Heat transfer medium supply unit 60 Heat exchanger 70 Gas A-containing gas supply unit (carbon dioxide-containing gas supply unit) 80 First outflow gas recovery section 90: Raw material gas supply unit.

Claims

1. A liquid fuel production system, characterized in that: The liquid fuel production system comprises: A gas adsorption and desorption section that adsorbs a given gas A and desorbs the gas A by heating; a heat transfer medium supplying section for supplying a heat transfer medium for heating the gas adsorption and desorption section to the gas adsorption and desorption section; a liquid fuel synthesis unit having a first gas flow path and a second gas flow path, wherein the first gas flow path contains a catalyst that promotes a conversion reaction from a raw gas containing at least carbon dioxide and hydrogen to a liquid fuel, and the second gas flow path allows a temperature-adjusting gas for adjusting the temperature of the first gas flow path to flow, a first outflow gas flows out of the first gas flow path, and a second outflow gas flows out of the second gas flow path; and a heat exchanger for performing heat exchange between the second outflowing gas and the heat transfer medium to heat the heat transfer medium, The second outflow gas contains condensable gas.

2. The liquid fuel production system according to claim 1, wherein: The gas adsorption and desorption section is a carbon dioxide adsorption and desorption section, The liquid fuel production system includes a carbon dioxide recovery unit having the carbon dioxide adsorption and desorption unit and recovering a carbon dioxide-concentrated gas from a carbon dioxide-containing gas.

3. The liquid fuel production system according to claim 2, wherein: The heat transfer medium contains the carbon dioxide concentrated gas.

4. The liquid fuel production system according to claim 1, wherein: The liquid fuel synthesis unit includes a water vapor separation membrane that allows water vapor to pass between the first gas flow path and the second gas flow path. The second outflow gas contains water vapor as a by-product of the conversion reaction that has permeated the water vapor separation membrane and permeated from the first gas flow path to the second gas flow path.

5. The liquid fuel production system according to claim 1, wherein: The liquid fuel synthesis unit includes a liquid fuel separation membrane that allows at least the liquid fuel to permeate between the first gas flow path and the second gas flow path. The second outflow gas includes the liquid fuel that has permeated the liquid fuel separation membrane and has permeated from the first gas flow path to the second gas flow path.

6. The liquid fuel production system according to claim 1, wherein: The temperature control gas contains at least one selected from hydrogen, carbon dioxide, carbon monoxide, nitrogen and oxygen as a main component.

7. The liquid fuel production system according to claim 2, wherein: The temperature-controlled gas contains the carbon dioxide concentrated gas, The liquid fuel production system includes a temperature control gas circulation unit that recovers the temperature control gas from the liquid fuel synthesis unit and supplies carbon dioxide derived from the carbon dioxide concentrated gas to the liquid fuel synthesis unit.

8. The liquid fuel production system according to claim 2, wherein: The carbon dioxide concentrated gas is supplied from the carbon dioxide recovery unit to the liquid fuel synthesis unit as a constituent component of the raw gas.

9. A method for producing a liquid fuel, characterized in that: The method for producing the liquid fuel comprises: Step I, contacting a gas containing carbon dioxide with a carbon dioxide adsorbent, thereby adsorbing the carbon dioxide on the carbon dioxide adsorbent; Step II, removing the carbon dioxide from the carbon dioxide adsorbent by heating, thereby recovering the carbon dioxide concentrated gas; Step III, performing a conversion reaction using a liquid fuel synthesis unit, the liquid fuel synthesis unit having a first gas flow path and a second gas flow path, the first gas flow path containing a catalyst that promotes the conversion reaction of converting a raw gas containing at least carbon dioxide and hydrogen into a liquid fuel, the second gas flow path allowing a temperature-adjusting gas that adjusts the temperature of the first gas flow path to flow, a first outflow gas flowing out of the first gas flow path, and a second outflow gas flowing out of the second gas flow path; and Step IV, heating the heat transfer medium used to heat the carbon dioxide adsorbent in step II by heat exchange using the second outflow gas as a heat medium, The second outflow gas contains condensable gas.

10. The manufacturing method according to claim 9, wherein: The temperature control gas contains at least one selected from hydrogen, carbon dioxide, carbon monoxide, nitrogen and oxygen as a main component.

11. The manufacturing method according to claim 9, wherein: The temperature-controlled gas contains the carbon dioxide concentrated gas, Carbon dioxide derived from the carbon dioxide concentrated gas is recovered from the second outflow gas and used as a constituent component of the raw gas.

12. The manufacturing method according to claim 9, wherein: The heat transfer medium contains the carbon dioxide concentrated gas.

13. The manufacturing method according to claim 9, wherein: The liquid fuel synthesis unit includes a water vapor separation membrane that allows water vapor to pass between the first gas flow path and the second gas flow path. The second outflow gas contains water vapor as a by-product of the conversion reaction that has permeated the water vapor separation membrane and permeated from the first gas flow path to the second gas flow path.

14. The manufacturing method according to claim 9, wherein: The liquid fuel synthesis unit includes a liquid fuel separation membrane that allows at least the liquid fuel to permeate between the first gas flow path and the second gas flow path. The second outflow gas includes the liquid fuel that has permeated the liquid fuel separation membrane and has permeated from the first gas flow path to the second gas flow path.

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