Liquid fuel production system and liquid fuel production method

Abstract

The main purpose of the present invention is to ease the restrictions on the installation site of a carbon dioxide capture system and / or to steadily secure a CO2 supply source and / or a cooling energy in a liquid fuel production system. According to an embodiment of the present invention, a liquid fuel production system is provided, which comprises: a gas adsorption / desorption unit which adsorbs a specific gas A and desorbs the gas A by heating; a heat transmitting medium supply unit which supplies a heat transmitting medium for heating the gas adsorption / desorption unit to the gas adsorption / desorption unit; a liquid fuel synthesis unit which has a first gas flow path and a second gas flow path, in which the first gas flow path accommodates a catalyst for facilitating a conversion reaction from a raw material gas containing at least carbon dioxide and hydrogen to a liquid fuel, the second gas flow path allows a temperature-controlling gas for controlling the temperature of the first gas flow path to pass therethrough, a first effluent gas flows out through the first gas flow path, and a second effluent gas flows out through the second gas flow path; and a heat exchanger which performs the heat exchange between the first effluent gas and the heat transmitting medium to heat the heat transmitting medium. In the liquid fuel production system, the first effluent gas comprises a condensable gas.

Description

[Technical Field]

[0001] The present invention relates to a liquid fuel production system and a method for producing liquid fuel. [Background technology]

[0002] In recent years, efforts have been made to separate and capture carbon dioxide (CO2) contained in the atmosphere and various emission sources in order to reduce the environmental burden. For example, Patent Document 1 discloses a carbon dioxide capture system that separates and captures CO2 by adsorbing CO2 onto a carbon dioxide adsorbent and desorbing it by heating.

[0003] Furthermore, with the aim of realizing a carbon-neutral society, it has been proposed to treat CO2 as a carbon resource and convert it into liquid fuel that is useful as a basic industrial raw material. For example, Patent Document 2 discloses a liquid fuel synthesis system that uses a membrane reactor containing a catalyst and a water vapor separation membrane to carry out a conversion reaction of a raw material gas containing CO2 and hydrogen (H2) into methanol. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2013 / 119929 [Patent Document 2] Japanese Patent Application Laid-Open No. 2018-8940 Summary of the Invention [Problem to be solved by the invention]

[0005] Carbon dioxide capture systems, which capture CO2 through adsorption and desorption, require a heat source to desorb the CO2, so they are subject to restrictions such as having to be installed in locations with heat sources such as geothermal energy, and the areas in which they can be operated are limited. On the other hand, a carbon-neutral liquid fuel synthesis system requires a stable CO2 supply source in addition to hydrogen obtained through water electrolysis as a raw material. Also, a liquid fuel synthesis system requires a large amount of energy for cooling the produced liquid fuel gas and condensable by-product gases for liquefaction and recovery.

[0006] The main object of the present invention is to alleviate restrictions on the installation location of a carbon dioxide capture system and / or to stably secure a CO2 supply source and / or cooling energy in a liquid fuel production system. [Means for solving the problem]

[0007] [1] A liquid fuel production system according to an embodiment of the present invention comprises: a gas adsorption / desorption unit that adsorbs a predetermined gas A and desorbs it by heating; a heat transfer medium supply unit that supplies a heat transfer medium for heating the gas adsorption / desorption unit to the gas adsorption / desorption unit; a liquid fuel synthesis unit that has a first gas flow path that accommodates a catalyst that promotes a conversion reaction from a raw material gas containing at least carbon dioxide and hydrogen to a liquid fuel, and a second gas flow path that circulates a temperature control gas that adjusts the temperature of the first gas flow path, and that discharges a first effluent gas from the first gas flow path and a second effluent gas from the second gas flow path; and a heat exchanger that exchanges heat between the first effluent gas and the heat transfer medium to heat the heat transfer medium, wherein the first effluent gas contains a condensable gas. [2] In the liquid fuel production system described in [1] above, the gas adsorption / desorption unit may be a carbon dioxide adsorption / desorption unit, and the system may include a carbon dioxide recovery unit that has the carbon dioxide adsorption / desorption unit and recovers carbon dioxide-enriched gas from the carbon dioxide-containing gas. [3] In the liquid fuel production system described in [2] above, the heat transfer medium may contain the carbon dioxide-enriched gas. [4] In the liquid fuel production system described in any one of [1] to [3] above, the liquid fuel synthesis unit may have a water vapor separation membrane that is permeable to water vapor between the first gas flow path and the second gas flow path, and the first outflow gas may contain the liquid fuel. [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 is permeable to at least the liquid fuel, and the first effluent gas may contain water vapor that is a by-product of the conversion reaction. [6] In the liquid fuel production system according to 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. [7] In the liquid fuel production system described in any one of [2] to [6] above, the temperature control gas may contain the carbon dioxide enriched gas, and a temperature control gas circulation unit may be provided which recovers the temperature control gas from the liquid fuel synthesis unit and supplies carbon dioxide derived from the carbon dioxide enriched gas to the liquid fuel synthesis unit. [8] In the liquid fuel production system described in any one of [2] to [7] above, the carbon dioxide enriched gas may be supplied from the carbon dioxide recovery unit to the liquid fuel synthesis unit as a constituent component of the raw material gas. [9] A method for producing a liquid fuel according to an embodiment of the present invention includes: step (I) of contacting a carbon dioxide-containing gas with a carbon dioxide adsorbent to adsorb the carbon dioxide onto the carbon dioxide adsorbent; step (II) of desorbing the carbon dioxide from the carbon dioxide adsorbent by heating to recover a carbon dioxide-enriched gas; step (III) of performing the conversion reaction using a liquid fuel synthesis unit having a first gas flow path containing a catalyst that promotes a conversion reaction from a feed gas containing at least carbon dioxide and hydrogen to a liquid fuel, and a second gas flow path through which a temperature control gas that adjusts the temperature of the first gas flow path flows, and wherein a first effluent gas is discharged from the first gas flow path and a second effluent gas is discharged from the second gas flow path; and step (IV) of heating a heat transfer medium that heats the carbon dioxide adsorbent in step (II) by heat exchange using the first effluent gas as a heat medium, wherein the first effluent gas contains a condensable gas.

[10] In the manufacturing method 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.

[11] In the manufacturing method described in [9] or

[10] above, the temperature-controlling gas may contain the carbon dioxide-enriched gas, and carbon dioxide derived from the carbon dioxide-enriched gas may be recovered from the second effluent gas and used as a constituent component of the raw material gas.

[12] In the manufacturing method according to any one of [9] to

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

[13] In the manufacturing method described in any one of [9] to

[12] above, the liquid fuel synthesis unit may have a water vapor separation membrane that is permeable to water vapor between the first gas flow path and the second gas flow path, and the first outflow gas may contain the liquid fuel.

[14] In the manufacturing method 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 is permeable to at least the liquid fuel, and the first outflow gas may contain water vapor that is a by-product of the conversion reaction. [Effects of the Invention]

[0008] According to the liquid fuel production system of the embodiment of the present invention, the gas containing a condensable gas flowing out from the liquid fuel synthesis unit can be used as a heat source for desorbing gas A (e.g., CO2). This makes it possible to reduce the cooling energy required to liquefy the condensable gas. Furthermore, when gas A is CO2, a heat source for CO2 desorption can be secured, which alleviates restrictions on the installation location of the carbon dioxide capture system (carbon dioxide capture unit). Furthermore, by using CO2 captured by the carbon dioxide capture system as a raw material for liquid fuel synthesis, a CO2 source for liquid fuel synthesis can be secured. [Brief explanation of the drawings]

[0009] [Figure 1A] FIG. 1A is a schematic diagram of a liquid fuel production system according to one embodiment of the present invention. [Figure 1B] FIG. 1B is a schematic configuration diagram of a liquid fuel production system according to another embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram showing an example of the configuration of a carbon dioxide adsorption / desorption unit used in the liquid fuel production system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. In addition, in order to clarify the description, the width, thickness, shape, etc. of each part may be shown schematically in the drawings compared to the embodiments, but this is merely an example and does not limit the interpretation of the present invention.

[0011] A. Liquid fuel production system FIG. 1A is a schematic diagram of a liquid fuel production system according to one embodiment of the present invention. The liquid fuel production system 1A shown in FIG. a gas adsorption / desorption section 10a that adsorbs a predetermined gas A and desorbs it by heating; a heat transfer medium supply unit (50) that supplies a heat transfer medium for heating the gas adsorption / desorption unit (10a) to the gas adsorption / desorption unit (10a); a liquid fuel synthesis unit 20 having a first gas flow path 20A accommodating a catalyst for promoting a conversion reaction from a raw material gas containing at least carbon dioxide and hydrogen to a liquid fuel, and a second gas flow path 20B for circulating a temperature control gas for adjusting the temperature of the first gas flow path 20A, wherein a first outflow gas is discharged from the first gas flow path 20A and a second outflow gas containing the temperature control gas is discharged from the second gas flow path 20B; a heat exchanger 60 for exchanging heat between the first effluent gas and the heat transfer medium to heat the heat transfer medium; Equipped with The first effluent gas contains condensable gases.

[0012] According to the liquid fuel production system 1A, the first effluent gas flowing out from the liquid fuel synthesis unit 20 is used as a heat source for desorption of gas A in the gas adsorption / desorption unit 10a. Specifically, the first effluent gas flowing out from the liquid fuel synthesis unit 20 is used as a heat source to heat a heat transfer medium for heating the gas adsorption / desorption unit 10a through heat exchange. Therefore, by using a carbon dioxide adsorption / desorption unit that adsorbs CO2 and desorbs it by heating as the gas adsorption / desorption unit 10a, a heat source for CO2 desorption can be secured, thereby easing restrictions on the installation location of the carbon dioxide capture system (carbon dioxide capture unit). Furthermore, the cooling energy required to liquefy the condensable gas (e.g., liquid fuel or steam) flowing out from the liquid fuel synthesis unit 20 can be reduced. Here, the first effluent gas containing the condensable gas condenses the condensable gas during heat exchange, preventing a significant decrease in temperature and allowing it to function as an efficient heat transfer medium. As a heat transfer medium for heating the gas adsorption / desorption section 10a, CO2-enriched gas or water (water vapor) can be used, as will be described later. These may be used alone or in combination by mixing or sequentially. Furthermore, for example, by supplying CO2 concentrated gas recovered in the carbon dioxide recovery section to the liquid fuel synthesis section 20 as a constituent component of the raw material gas, a CO2 source for liquid fuel production can be secured.

[0013] In this specification, the liquid fuel is a fuel that is in a liquid state at normal temperature and pressure, or a fuel that can be liquefied under normal temperature and pressure. Examples of the fuel that is in a liquid state at normal temperature and pressure include methanol, ethanol, C n H 2(m-2n) (m is an integer less than 90, and n is an integer less than 30), and mixtures thereof. Examples of fuels that can be liquefied under normal temperature and pressure include propane, butane, and mixtures thereof.

[0014] In the liquid fuel production system 1A, a gas A-containing gas containing a predetermined gas A is supplied to the gas adsorption / desorption unit 10a from a gas A-containing gas supply unit 70. Furthermore, a raw material gas for synthesizing a liquid fuel is supplied from a raw material gas supply unit 90 to a first gas flow path 20A of the liquid fuel synthesis unit 20, and a conversion reaction proceeds by a catalyst accommodated in the first gas flow path 20A so as to be able to come into contact with the raw material gas.

[0015] For example, the reaction formula (1) of the conversion reaction in which methanol is synthesized by catalytic hydrogenation of a raw material gas containing CO2 and hydrogen in the presence of a catalyst is as follows:

[0016] CO2 + 3H2 ⇔ CH3OH + H2O (1)

[0017] The above reaction is an equilibrium reaction, and in order to increase both the conversion rate and the reaction rate, it is preferable to carry out the reaction under high temperature and pressure (for example, 180°C or higher, 1 MPa or higher). The liquid fuel and the by-product water are in a gaseous state when synthesized, and remain in that state at least until they flow out of the liquid fuel synthesis unit 20.

[0018] In one embodiment, the partition wall 23 interposed 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 is permeable to water vapor, thereby allowing water vapor, a by-product of the conversion reaction, to flow from the first gas flow path 20A to the second gas flow path 20B. The water vapor separation membrane will be described later.

[0019] A temperature control gas is supplied to the second gas flow path 20B from a temperature control gas supply unit 30. The temperature control gas is a gas that adjusts the temperature of the first gas flow path 20A, and is, for example, a cooling medium that cools the first gas flow path 20A. In this embodiment, the temperature control gas also functions as a sweep gas that sweeps water vapor that has flowed into the second gas flow path 20B.

[0020] Gases that did not permeate the water vapor separation membrane, such as liquid fuel and unreacted raw material gas (residual raw material gas), flow out as a first outflow gas from the first gas flow path 20A. The first outflow gas is supplied to the heat exchanger 60 via the first outflow gas recovery pipe 82 and undergoes heat exchange with the heat transfer medium supplied by the heat transfer medium supply unit 50. As a result, the heat transfer medium is heated to a temperature capable of heating the gas adsorption / desorption unit 10a to a predetermined temperature (a temperature at which gas A can be desorbed), and the liquid fuel contained in the first outflow gas is condensed and recovered from the drain trap 84 and the liquefied matter recovery pipe 86. The residual raw material gas separated from the liquid fuel is reused as raw material gas as necessary.

[0021] On the other hand, a second outflow gas containing water vapor and a temperature control gas flows out from the second gas flow path 20B. The second outflow gas is separated into water and a temperature control gas by, for example, gas-liquid separation, and then removed or reused.

[0022] In another embodiment, the partition wall 23 interposed 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 is permeable to liquid fuel, thereby allowing the liquid fuel, which is the target product of the conversion reaction, to flow from the first gas flow path 20A to the second gas flow path 20B. As the liquid fuel separation membrane, for example, one described in JP 2020-23488 A can be used. Note that the liquid fuel separation membrane allows liquid fuel to permeate with higher selectivity than water vapor, but does not completely separate the two.

[0023] A temperature control gas supply unit 30 supplies the second gas flow passage 20B with a temperature control gas that also functions as a sweep gas for sweeping the liquid fuel that has flowed into the second gas flow passage 20B.

[0024] Gases that did not permeate the liquid fuel separation membrane, such as water vapor and unreacted raw material gas (residual raw material gas), flow out as a first outflow gas from the first gas flow path 20A. The first outflow gas is supplied to the heat exchanger 60 via the first outflow gas recovery pipe 82 and undergoes heat exchange with the heat transfer medium supplied by the heat transfer medium supply unit 50. As a result, the heat transfer medium is heated to a temperature capable of heating the gas adsorption / desorption unit 10a to a predetermined temperature (a temperature at which gas A can be desorbed), and the water vapor contained in the first outflow gas condenses and is recovered from the drain trap 84 and the liquefied matter recovery pipe 86. The residual raw material gas separated from the water vapor is reused as raw material gas as necessary.

[0025] On the other hand, a second outflow gas containing liquid fuel and temperature control gas flows out from the second gas flow passage 20B. The second outflow gas is separated into the liquid fuel and the temperature control gas by, for example, gas-liquid separation, and each of the liquid fuel and the temperature control gas is recovered or reused.

[0026] In yet another embodiment, the partition wall 23 interposed between the first gas flow path 20A and the second gas flow path 20B of the liquid fuel synthesis unit 20 is a gas-impermeable partition wall that does not allow gas to pass through. In this embodiment, a first outflow gas containing liquid fuel, steam, and residual raw material gas flows out from the first gas flow path 20A, and a temperature control gas flows out from the second gas flow path 20B as a second outflow gas. The first outflow gas is supplied to the heat exchanger 60 via the first outflow gas recovery pipe 82 and heat-exchanges with the heat transfer medium supplied by the heat transfer medium supply unit 50. As a result, the heat transfer medium is heated to a temperature capable of heating the gas desorbing unit 10a to a predetermined temperature (a temperature at which gas A can be desorbed), and condensable gases (specifically, liquid fuel and steam) contained in the first outflow gas are condensed and recovered from the drain trap 84 and the liquefied matter recovery pipe 86.

[0027] In the illustrated example, the first gas flow path 20A and the second gas flow path 20B are separated into upper and lower sections by a partition wall 23, but the second gas flow path 20B may be arranged so as to be able to adjust the temperature of the first gas flow path 20A. For example, the liquid fuel synthesis unit 20 may have a double-pipe structure, with one of the inner pipe and the outer pipe serving as the first gas flow path and the other serving as the second gas flow path.

[0028] 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, where "containing as a main component" means containing at least one of the elements at the highest content.

[0029] A-1. An example of a liquid fuel production system Hereinafter, a liquid fuel production system 1B shown in FIG. 1B will be described 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. Note that the liquid fuel production system 1B includes a liquid fuel synthesis unit having a water vapor separation membrane, and the temperature control gas supplied to the liquid fuel synthesis unit can also function as a sweep gas. Therefore, in the following description, the temperature control gas may be referred to as a sweep gas.

[0030] The liquid fuel production system 1B shown in FIG. a carbon dioxide recovery unit 10 that recovers CO2-enriched gas from a CO2-containing gas, the carbon dioxide recovery unit 10 including a carbon dioxide adsorption / desorption unit 10a that adsorbs CO2 and desorbs CO2 by heating; a liquid fuel synthesis unit (20) including a first gas flow path (20A) containing a catalyst for promoting a conversion reaction from a feed gas containing at least CO2 and hydrogen to a liquid fuel, and a second gas flow path (20B) through which a sweep gas for adjusting the temperature of the first gas flow path (20A) flows, and through which a first effluent gas flows from the first gas flow path (20A) and a second effluent gas flows from the second gas flow path (20B); a raw material gas supply unit 90 that supplies raw material gas to the liquid fuel synthesis unit 20; a sweep gas supply unit (30) that supplies the CO2-enriched gas to the liquid fuel synthesis unit (20) as a constituent of the sweep gas; a sweep gas circulation unit (40) for recovering the sweep gas from the liquid fuel synthesis unit (20) and supplying CO2 derived from the CO2-enriched gas to a raw material gas supply unit (90); a heat transfer medium supply unit (50) that supplies the CO2-enriched gas to the carbon dioxide adsorption / desorption unit (10a) as a heat transfer medium for heating the carbon dioxide adsorbent; a heat exchanger 60 for exchanging heat between the first outflow gas and the heat transfer medium to heat the heat transfer medium; The CO2-containing gas is supplied from the carbon dioxide-containing gas supply unit 70 to the carbon dioxide recovery unit 10. Hereinafter, each component will be described in more detail with reference to the liquid fuel production system 1B.

[0031] A-1-1. Carbon dioxide capture section The carbon dioxide capture unit 10 has a carbon dioxide adsorption / desorption unit 10a. The carbon dioxide capture unit 10 may further have a pump, a carbon dioxide-enriched gas storage unit, and the like. The carbon dioxide adsorption / desorption unit 10a houses, for example, a carbon dioxide adsorbent that adsorbs CO2 upon contact with a CO2-containing gas and desorbs CO2 upon heating. With this configuration, the carbon dioxide capture unit 10 supplies a CO2-containing gas to the carbon dioxide adsorption / desorption unit 10a to adsorb CO2 onto the carbon dioxide adsorbent, then heats the carbon dioxide adsorbent to desorb CO2, and sucks the desorbed CO2 with a pump, thereby recovering a CO2-enriched gas containing CO2 at a higher concentration than the CO2-containing gas supplied to the carbon dioxide adsorption / desorption unit 10a.

[0032] The carbon dioxide adsorption / desorption unit 10a has a configuration that allows gas to flow in and out, and the carbon dioxide adsorbent is arranged so as to be able to come into contact with the inflowing CO2-containing gas. Preferably, the carbon dioxide adsorbent is supported on any appropriate substrate. In one embodiment, the carbon dioxide adsorption / desorption unit 10a includes a substrate and a carbon dioxide adsorption layer that is arranged on the surface of the substrate and contains the carbon dioxide adsorbent.

[0033] The structure of the substrate is not particularly limited, and examples thereof include a monolithic shape, a filter structure such as a filter cloth, and a pellet structure. The monolithic shape refers to a shape having a plurality of cells penetrating in the longitudinal direction, and is a concept that includes a honeycomb shape. In one embodiment, the substrate is a honeycomb substrate having a plurality of cells. Examples of the cross-sectional shape of the cells (cross-sectional shape in a direction perpendicular to the longitudinal direction of the honeycomb substrate) include a triangle, a rectangle, a pentagon, a polygon with hexagons or more, a circle, and an ellipse.

[0034] 2, the carbon dioxide adsorption / desorption unit 10a includes 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, on the surface of the partition walls 11a). The cross-sectional shape of the cells in the illustrated honeycomb substrate is quadrangular, and a CO2-containing gas is supplied to spaces in the cross section where the carbon dioxide adsorption layer 13 is not formed.

[0035] Representative materials for the substrate include ceramics. Examples of ceramics include silicon carbide, silicon-silicon carbide composite materials, cordierite, mullite, alumina, silicon nitride, spinel, silicon carbide-cordierite composite materials, lithium aluminum silicate, and aluminum titanate. The materials for the substrate can be used alone or in combination.

[0036] The carbon dioxide adsorption layer is not particularly limited as long as it is disposed on the surface of the substrate so as to be in contact with the CO2-containing gas. The carbon dioxide adsorption layer may contain substantially only the carbon dioxide adsorbent, or may contain other components (e.g., a porous carrier) in addition to the carbon dioxide adsorbent.

[0037] Any suitable compound capable of adsorbing and desorbing CO may be used as the carbon dioxide adsorbent. Examples of carbon dioxide adsorbents include nitrogen-containing compounds, which will be described later; alkaline compounds such as sodium hydroxide and potassium hydroxide; carbonates such as calcium carbonate and potassium carbonate; bicarbonates such as calcium bicarbonate and potassium bicarbonate; metal-organic frameworks (MOFs) such as MOF-74, MOF-200, and MOF-210; zeolites; activated carbon; nitrogen-doped carbon; and ionic liquids.

[0038] Among carbon dioxide adsorbents, nitrogen-containing compounds are more preferred. Specific examples of nitrogen-containing compounds include amine compounds such as monoethanolamine, diethanolamine, triethanolamine, N-(3-aminopropyl)diethanolamine, aminopropyltrimethoxysilane, and polyvinylamine; imine compounds such as polyethyleneimine and polyethyleneimine-trimethoxysilane; amide compounds such as polyamidoamine; piperazine compounds such as 1-(2-hydroxyethyl)piperazine; and aminosilane coupling agents such as 3-aminopropyltriethoxysilane and N-(2-aminoethyl)-3-aminopropyl-trimethoxysilane. Carbon dioxide adsorbents can be used alone or in combination.

[0039] 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 the carbon dioxide adsorbent and, optionally, other components in a solvent. Examples of the solvent include water, alcohols, diols, and combinations thereof. Next, the carbon dioxide adsorption layer-forming liquid is applied to a substrate, and the coating is dried and, if necessary, sintered to form a carbon dioxide adsorption layer.

[0040] A-1-2.Liquid fuel synthesis department The liquid fuel synthesis unit 20 is a so-called membrane reactor for converting the raw material gas into liquid fuel. The shape of the liquid fuel synthesis unit 20 is not particularly limited, and may be, for example, a monolith, a flat plate, a tube, a cylinder, a columnar shape, a polygonal pillar shape, or the like.

[0041] The liquid fuel synthesis section 20 includes a catalyst 22 that promotes a conversion reaction from a feed gas containing at least CO2 and hydrogen to liquid fuel, a water vapor separation membrane 24, a non-permeation side space 20A, and a permeation side space 20B. The liquid fuel synthesis section 20 is provided with a first supply port s1 and a first discharge port d1 that communicate with each other via the non-permeation side space 20A, and a second supply port s2 and a second discharge port d2 that communicate with each other via the permeation side space 20B.

[0042] The non-permeation side space 20A is a space on the non-permeation side of the water vapor separation membrane 24. A raw material gas is supplied to the non-permeation side space 20A from the raw material gas supply unit 90 via a first supply port s1. The liquid fuel and remaining raw material gas synthesized in the catalyst 22 flow out as a first effluent gas from the non-permeation side space 20A via a first discharge port d1 to the first effluent gas recovery unit 80. In other words, the non-permeation side space 20A is a first gas flow path.

[0043] The permeate side space 20B is a space on the permeate side of the water vapor separation membrane 24. As described below, water vapor and a portion of the hydrogen in the feed gas permeate through the water vapor separation membrane 24, and thus water vapor and hydrogen flow into the permeate side space 20B. A sweep gas is supplied from the sweep gas supply unit 30 through a second supply port s2 to the permeate side space 20B. The water vapor, hydrogen, and sweep gas flow as a second outflow gas from the permeate side space 20B through a second outlet port d2 to the sweep gas circulation unit 40. In other words, the permeate side space 20B serves as a second gas flow path.

[0044] The catalyst 22 promotes the conversion reaction from the raw material gas to liquid fuel. The catalyst is disposed in the non-permeation side space 20A. The catalyst is preferably filled in the non-permeation side space 20A, but may also be disposed in the form of layers or islands on the surface of the water vapor separation membrane 24. When the catalyst is in particulate form as in the illustrated example, the particle size (diameter) of the catalyst particles can be, for example, 0.5 mm or more and 10 mm or less. The catalyst particles may be composed of catalyst alone, or may be configured such that the catalyst is supported on carrier particles. The carrier particles are preferably porous particles.

[0045] Any catalyst suitable for the conversion reaction to the desired liquid fuel can be used as the catalyst. Specifically, metal catalysts (copper, palladium, etc.), oxide catalysts (zinc oxide, zirconia, gallium oxide, etc.), and catalysts made by combining these (copper-zinc oxide, copper-zinc oxide-alumina, copper-zinc oxide-chromium oxide-alumina, copper-cobalt-titania, and catalysts obtained by modifying these with palladium, etc.) can be used.

[0046] The water vapor separation membrane 24 allows water vapor, a by-product of the conversion reaction from the feed gas to liquid fuel, to pass through, thereby utilizing the equilibrium shift effect to shift the reaction equilibrium of the above formula (1) to the product side.

[0047] The molecular diameter of water (0.26 nm) is close to the molecular diameter of hydrogen (0.296 nm). Therefore, not only the water vapor that is a by-product of the conversion reaction but also some of the hydrogen contained in the raw material gas can permeate the water vapor separation membrane 24.

[0048] The water vapor separation membrane 24 has a resistance of 100 nmol / (s·Pa·m 2 The water vapor permeability coefficient can be determined by a known method (see Ind. Eng. Chem. Res., 40, 163-175 (2001)).

[0049] 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 permeate and the less permeable it is for components other than water vapor (such as hydrogen, carbon dioxide, and liquid fuel). The separation factor can be determined by a known method (see Fig. 1 in "Separation and Purification Technology 239 (2020) 116533").

[0050] Any appropriate membrane can be used as the water vapor separation membrane 24. In one embodiment, an inorganic membrane can be used as the water vapor separation membrane 24. Inorganic membranes are preferred because they have heat resistance, pressure resistance, water vapor resistance, and the like. Examples of inorganic membranes include zeolite membranes, silica membranes, alumina membranes, and composite membranes thereof. For example, an LTA-type zeolite membrane, in which the molar ratio (Si / Al) of silicon element (Si) to aluminum element (Al) is 1.0 or more and 3.0 or less, is preferred because of its excellent water vapor permeability.

[0051] The zeolite membrane used as the water vapor separation membrane 24 can be obtained by the manufacturing method described in JP 2004-66188 A. The silica membrane used as the water vapor separation membrane 24 can be obtained by the manufacturing method described in WO 2008 / 050812 A.

[0052] In the illustrated example, the water vapor separation membrane 24 is supported by a porous support 26 .

[0053] The porous support 26 is made of a porous material. Examples of the porous material include ceramic materials, metal materials, and resin materials, with ceramic materials being particularly suitable. Examples of aggregates for ceramic materials include alumina (Al2O3), titania (TiO2), mullite (Al2O3·SiO2), cerium dioxide, and cordierite (Mg2Al4Si5O 18 ) can be used, and alumina is preferred in consideration of availability, clay stability, and corrosion resistance. As the inorganic binder for the ceramic material, at least one of titania, mullite, sinterable alumina, silica, glass frit, clay minerals, and sinterable cordierite can be used. The ceramic material does not necessarily need to contain an inorganic binder.

[0054] The average pore diameter of the porous support can be 5 μm or more and 25 μm or less. The average pore diameter of the porous support can be measured by mercury intrusion porosimetry. The porosity of the porous support can be 25% or more and 50% or less. The average particle diameter of the porous material constituting the porous support can be 1 μm or more and 100 μm or less. In this embodiment, the average particle diameter is the arithmetic mean value of the maximum diameters of 30 particles (randomly selected) measured by cross-sectional microstructure observation using a SEM (Scanning Electron Microscope).

[0055] 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 CO2-containing gas from the atmosphere or various facilities such as factories and commercial facilities to the carbon dioxide capture unit 10 (more specifically, the carbon dioxide adsorption / desorption unit 10a).

[0056] A-1-4. Sweep gas supply unit The sweep gas supply unit 30 is configured to supply CO2-enriched gas as a constituent component of the sweep gas from the carbon dioxide capture unit 10 to the liquid fuel synthesis unit 20. The sweep gas supply unit 30 has a carbon dioxide-enriched gas supply pipe 32, a hydrogen supply pipe 34, and a hydrogen generation unit 36. One end of the carbon dioxide-enriched gas supply pipe 32 is connected to the carbon dioxide capture 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 generation unit 36, and the other end is connected to the carbon dioxide-enriched gas supply pipe 32. The hydrogen generation unit 36 ​​is, for example, hydrogen production equipment that uses water electrolysis technology. The CO2-enriched gas supplied from the carbon dioxide capture unit 10 to the liquid fuel synthesis unit 20 via the carbon dioxide-enriched gas supply pipe 32 is mixed with hydrogen supplied from the hydrogen generation unit 36, thereby generating a sweep gas containing CO2-enriched gas and hydrogen. The sweep 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 synthesis section 20.

[0057] In one embodiment, the sweep gas contains hydrogen as a major component, where "containing hydrogen as a major component" means that hydrogen has the highest content among the gases contained in the sweep gas.

[0058] The CO2 concentration in the sweep gas is, for example, 10% by volume to 40% by volume, preferably 20% by volume to 30% by volume. The hydrogen concentration in the sweep gas is, for example, 60% by volume to 90% by volume, preferably 70% by volume to 80% by volume. When the sweep gas contains CO2 and hydrogen in the above ratios, the gas (remaining raw material gas and sweep gas) recovered from the liquid fuel synthesis section can be suitably recycled and reused as raw material gas.

[0059] A-1-5. First outflow gas recovery section, heat transfer medium supply section, and heat exchanger The first outflow gas recovery section 80 has a first outflow gas recovery pipe 82, a drain trap 84, and a liquefied matter recovery pipe 86. One end of the first outflow gas recovery pipe 82 is connected to a first outlet d1 of the liquid fuel synthesis section 20, and the other end is connected to the drain trap 84. A first outflow gas containing the liquid fuel that did not permeate the water vapor separation membrane 24 and the remaining raw material gas flows into the first outflow gas recovery pipe 82 from the first outlet d1.

[0060] The heat transfer medium supply unit 50 has a heat transfer medium supply pipe 52 and supplies the CO2-enriched gas recovered in the carbon dioxide capture unit 10 to the carbon dioxide adsorption / desorption unit 10a as a heat transfer medium for heating the carbon dioxide adsorbent. The CO2-enriched gas recovered in the carbon dioxide capture unit 10 is supplied again to the carbon dioxide adsorption / desorption unit 10a via the heat transfer medium supply pipe 52, and by recovering the desorbed CO2, the CO2-enriched gas is recovered again in the carbon dioxide capture unit 10 as a CO2-enriched gas containing CO2 at a higher concentration than the CO2-enriched gas supplied as the heat transfer medium. Specifically, the CO2-enriched gas as the heat transfer medium flows through the same flow path as the CO2-containing gas in the carbon dioxide adsorption / desorption unit 10a to heat the carbon dioxide adsorbent / desorbent, and as a result, it can be recovered in the carbon dioxide capture unit 10 as a CO2-enriched gas with a higher concentration that further contains the desorbed CO2. For example, in the carbon dioxide adsorption / desorption unit 10a shown in FIG. 2, 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 used as a shared flow path for the CO2-containing gas and the CO2-enriched gas serving as a heat transfer medium. By circulating the CO2-enriched gas in this manner, a CO2-enriched gas containing a high concentration of CO2 (e.g., a CO2 concentration of 50% by volume or more) can be suitably obtained. Without being limited to the illustrated example, the heat transfer medium supply pipe 52 may be connected to the carbon dioxide-containing gas supply unit 70 to supply the CO2-enriched gas to the carbon dioxide adsorption / desorption unit 10a. Furthermore, although not shown, the heat transfer medium supply unit may further include a second heat transfer medium supply pipe that supplies a heat transfer medium other than the CO2-enriched gas (e.g., water vapor) to the carbon dioxide adsorption / desorption unit. In this case, the second heat transfer medium supply pipe may be connected to another heat transfer medium storage unit, and the other heat transfer medium may be heated by heat exchange with the heat exchanger 60 and supplied to the carbon dioxide adsorption / desorption unit 10a.

[0061] The heat exchanger 60 is interposed between the heat transfer medium supply section 50 and the first outflow gas recovery section 80. Specifically, the heat exchanger 60 has a first flow path 62 interposed in the heat transfer medium supply piping 52 and a second flow path 64 interposed in the first outflow gas recovery piping 82, and is configured to be able to exchange heat between a first fluid flowing through the first flow path 62 and a second fluid flowing through the second flow path 64.

[0062] According to the above configuration, heat exchange occurs between the heat transfer medium (specifically, CO2-enriched gas) flowing through the first flow path 62 and the first outflow gas flowing through the second flow path 64, thereby heating the heat transfer medium. Furthermore, by condensing condensable gases such as liquid fuel contained in the first outflow gas during the heat exchange, the heat of condensation can be used for the heat exchange, which can contribute to further improvement of thermal efficiency.

[0063] The temperature of the heat transfer medium before the heat exchange is, for example, 5°C or higher and 100°C or lower, and preferably 10°C or higher and 80°C or lower. The temperature of the heat transfer medium after the heat exchange is, for example, 60°C or higher and 200°C or lower, and preferably 90°C or higher and 160°C or lower. The temperature of the first effluent gas before the heat exchange is, for example, 150°C or higher and 350°C or lower, and preferably 200°C or higher and 300°C or lower. The temperature of the first effluent gas after the heat exchange is, for example, 25°C or higher and 250°C or lower, and preferably 50°C or higher and 200°C or lower.

[0064] The concentration of the condensable gas in the first outflow gas before heat exchange is, for example, 5% by volume or more and 50% by volume or less, and preferably 10% by volume or more and 40% by volume or less. If the concentration of the condensable gas in the first outflow gas is within the above range, heat exchange can be performed with higher efficiency.

[0065] The drain trap 84 is disposed downstream of the heat exchanger 60. The drain trap 84 separates the liquid (typically, liquid fuel) and gas condensed in the heat exchanger 60. The separated liquid is recovered from a liquefied matter recovery pipe 86.

[0066] The gas (remaining raw material gas) separated by the drain trap 84 is re-supplied to the raw material gas supply unit 90 as necessary.

[0067] A-1-6. Sweep gas circulation section The sweep gas circulation unit 40 has a second outflow gas recovery pipe 41, a condenser 42, a liquefied matter recovery pipe 43, and a recovered gas supply pipe 44. The second outflow gas recovery pipe 41 is connected to the second outlet d2 of the liquid fuel synthesis unit 20 and the condenser 42, and supplies the second outflow gas containing water vapor and hydrogen that have permeated the water vapor separation membrane 24 and the sweep gas from the liquid fuel synthesis unit 20 to the condenser 42.

[0068] The condenser 42 liquefies the condensable gas (typically water vapor) in the second effluent gas and separates it from the sweep gas and hydrogen. The liquefied product (typically water) is recovered through a liquefied product recovery pipe 43. The separated gas (recovered gas) is supplied to the raw material gas supply unit 90 via a recovered gas supply pipe 44. The recovered gas contains the sweep gas and hydrogen that has permeated the water vapor separation membrane 24.

[0069] A-1-7. Raw material gas supply unit The raw material gas supply unit 90 has a pressure booster unit and the like, and supplies the raw material gas at the desired pressure and temperature to the liquid fuel synthesis unit 20. In the illustrated example, the recovered gas is supplied to the liquid fuel synthesis unit 20 as the raw material gas, but the raw material gas may be prepared as needed by further mixing the remaining raw material gas recovered from the first effluent gas, separately prepared hydrogen, carbon dioxide, or a mixed gas thereof. Alternatively, the raw material gas may not contain any recovered gas at all.

[0070] 1B, 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 has been described. However, the above description can be similarly applied to an embodiment in which the liquid fuel synthesis unit has a liquid fuel separation membrane between the first gas flow path 20A and the second gas flow path. Specifically, the first effluent gas containing water vapor and the remaining raw material gas flowing out from the non-permeation side space 20A is used for heat exchange with a heat transfer medium, and a liquid (typically, water) and gas are separated by condensation during the heat exchange. The separated gas (typically, the remaining raw material gas) is supplied to the raw material gas supply unit and can be reused as a constituent component of the raw material gas. The second effluent gas contains liquid fuel and a sweep gas (preferably a sweep gas containing CO2-enriched gas), which are separated by gas-liquid separation. The liquid fuel is recovered from the liquefied matter recovery pipe, and the sweep gas is supplied to the raw material gas supply unit and can be used as a constituent component of the raw material gas.

[0071] A-2. First modified example In the embodiment shown in FIG. 1B, the liquid fuel synthesis section is a membrane reactor, but this configuration is not limited thereto. For example, the liquid fuel synthesis section may have, from upstream to downstream, a catalyst section containing a catalyst, a separation section having a water vapor separation membrane, a non-permeate side space, and a permeate side space, as separate reactors. The liquid fuel gas, by-product gas (water vapor), and remaining raw material gas flowing out of the catalyst section into the non-permeate side space of the separation section. The by-product gas and hydrogen that permeate the water vapor separation membrane flow out of the permeate side space of the separation section together with the sweep gas as a second effluent gas. The liquid fuel and remaining raw material gas that do not permeate the water vapor separation membrane flow out of the non-permeate side space as a first effluent gas. In Modification 1, since the gas flowing out of the catalyst section flows directly into the separation section, the non-permeate side space of the separation section is considered to form the first gas flow path together with the catalyst section, and the permeate side space of the separation section is considered to be the second gas flow path.

[0072] A-3. Second modified example In the embodiment shown in FIG. 1B, the flow directions of the raw gas and the sweep gas are opposite to each other in a side view of the water vapor separation membrane 24, but they may also be in the same direction.

[0073] A-4. Third variant The liquid fuel synthesis unit 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 coming into direct contact with the water vapor separation membrane 24. By physically isolating the catalyst and the water vapor separation membrane 24 by the buffer layer, it is possible to prevent cracks from occurring in the water vapor separation membrane 24 originating from the contact point with the catalyst, even if the catalyst is heated by the heat of reaction.

[0074] B. Liquid Fuel Manufacturing Methods A method for producing a liquid fuel according to an embodiment of the present invention includes: a step (I) of contacting a CO2-containing gas with a carbon dioxide adsorbent to adsorb the carbon dioxide onto the carbon dioxide adsorbent; a step (II) of desorbing the carbon dioxide from the carbon dioxide adsorbent by heating to recover a carbon dioxide-enriched gas; a step (III) of carrying out the conversion reaction using a liquid fuel synthesis unit having a first gas flow path containing a catalyst that promotes a conversion reaction from a raw material gas containing at least carbon dioxide and hydrogen to a liquid fuel, and a second gas flow path through which a temperature control gas that adjusts the temperature of the first gas flow path flows, wherein a first effluent gas flows from the first gas flow path and a second effluent gas flows from the second gas flow path; a step (IV) of heating a heat transfer medium for heating the carbon dioxide adsorbent in the step (II) by heat exchange using the first effluent gas as a heat medium; Including, The first effluent gas contains condensable gases. Preferably, the heat exchange is carried out by utilizing the heat of condensation of the condensable gas. The liquid fuel production method according to the embodiment of the present invention can be suitably carried out by using the liquid fuel production system described in Section A. 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. In one embodiment, the temperature control gas contains the CO2-enriched gas, and carbon dioxide derived from the CO2-enriched gas is recovered from the second effluent gas and used as a constituent component of the raw material gas. In one embodiment, the heat transfer medium contains the CO2 enriched gas.

[0075] B-1. Process (I) In step (I), the CO2-containing gas is brought into contact with a carbon dioxide adsorbent to adsorb CO2 to 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 x 10 5 Pa or more 2.0×10 5 The relative humidity (RH) of the CO2-containing gas is, for example, 10% RH or more and 60% RH or less. The duration of step (I) is, for example, 15 minutes or more and 3 hours or less. The flow velocity of the CO2-containing gas in step (I) is, for example, 0.5 m / s or more and 5 m / s or less.

[0076] The CO2 adsorption rate in step (I) (= (CO2 concentration in gas before contact with carbon dioxide adsorbent - CO2 concentration in gas after contact with carbon dioxide adsorbent) / CO2 concentration in gas before contact with carbon dioxide adsorbent x 100) is, for example, 60% or more, preferably 75% or more, more preferably 80% or more, and for example, 90% or less.

[0077] B-2. Process (II) In step (II), CO2 is desorbed from the carbon dioxide adsorbent by heating to recover a CO2-enriched 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 desorbed (released) CO2 from the carbon dioxide adsorbent is sucked in by a pump or the like to recover a CO2-enriched gas.

[0078] The heating temperature in step (II) is, for example, more 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.

[0079] The CO2-enriched gas contains CO2 at a higher concentration than the CO2-containing gas. The CO2 concentration in the CO2-enriched gas is, for example, 50% by volume or more, preferably 60% by volume or more, more preferably 80% by volume or more, and is, for example, 100% by volume or less. The CO2-enriched gas having such a CO2 concentration is suitable as a constituent component of the sweep gas (ultimately, the raw material gas).

[0080] In one embodiment, the carbon dioxide adsorbent is heated using a heat transfer medium containing CO2-enriched gas. For example, CO2-enriched gas may be used as the heat transfer medium. Specifically, the recovered CO2-enriched gas is heated to a temperature at which the carbon dioxide adsorbent can desorb CO2, and the CO2-enriched gas is used to heat the carbon dioxide adsorbent. For example, in the liquid fuel production system 1B shown in FIG. 1B, the CO2-enriched gas flowing out of the carbon dioxide capture unit 10 is heated in a heat exchanger 60 and then resupplied as a heat transfer medium to the carbon dioxide adsorption / desorption unit 10a that adsorbed CO2. The desorbed CO2 is then recovered, resulting in a CO2-enriched gas that contains a higher concentration of CO2 than when it was supplied as a heat transfer medium. By repeatedly circulating the CO2-enriched gas in this manner, a CO2-enriched gas containing a higher concentration of CO2 can be recovered.

[0081] B-3.Process (III) In step (III), the conversion reaction is carried out using a liquid fuel synthesis unit having a first gas flow path containing a catalyst for converting a feed gas containing at least carbon dioxide and hydrogen into a liquid fuel, and a second gas flow path through which a temperature-controlling gas for adjusting the temperature of the first gas flow path flows, and the first effluent gas flows from the first gas flow path and the second effluent gas flows from the second gas flow path. Specifically, the feed gas is introduced into the first gas flow path, and the feed gas containing CO2 and hydrogen is catalytically hydrogenated in the presence of a catalyst to synthesize methanol, as shown in reaction formula (1). A temperature-controlling gas is introduced into the second gas flow path.

[0082] The liquid fuel synthesis unit has, for example, a separation membrane between the first gas flow path and the second gas flow path that allows either one of the condensable gases, liquid fuel or water vapor, to permeate and separate it from the other. A water vapor separation membrane or a liquid fuel separation membrane can be used as such a separation membrane. When the liquid fuel synthesis unit has a water vapor separation membrane, a first effluent gas containing liquid fuel and a second effluent gas containing water vapor are discharged from the liquid fuel synthesis unit. When the liquid fuel synthesis unit has a liquid fuel separation membrane, a first effluent gas containing water vapor and a second effluent gas containing liquid fuel are discharged from the liquid fuel synthesis unit.

[0083] The CO concentration in the raw material gas is, for example, 10% by volume to 40% by volume, and preferably 20% by volume to 30% by volume. The hydrogen concentration in the raw material gas is, for example, 60% by volume to 90% by volume, and preferably 70% by volume to 80% by volume.

[0084] The reaction temperature in step (III) is, for example, 180°C or higher, preferably 200°C or higher and 350°C or lower. The pressure is, for example, 1 MPa or higher, preferably 2 MPa or higher and 6 MPa or lower. The flow rate of the raw material gas is appropriately adjusted depending on the catalyst characteristics, reactor type, etc., and is, when expressed in terms of gas hourly space velocity (GHSV) under standard conditions (0°C, 1 atmosphere), for example, 1000 / h or higher and 50000 / h or lower, preferably 2000 / h or higher and 20000 / h or lower, and more preferably 3000 / h or higher and 12000 / h or lower.

[0085] B-4.Process (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 first effluent gas as a heat medium. By using the first effluent gas obtained in step (III) as a heat source for CO2 desorption, it is possible to reduce the cooling energy required to cool the condensable gases (e.g., water, liquid fuel) contained in the first effluent gas and to alleviate restrictions on the installation location of the carbon dioxide capture system that performs steps (I) and (II). The heat transfer medium is not particularly limited as long as the effects of the present invention can be obtained, and for example, CO2-enriched gas is preferably used.

[0086] In the heat exchange, it is preferable to condense the condensable gas contained in the first outflow gas. This allows the heat of condensation to be used for the heat exchange, and since the temperature is kept constant during condensation, a sudden temperature change can be prevented. Furthermore, the condensable gas contained in the first outflow gas can be easily separated from the remaining raw material gas.

[0087] In one embodiment, the sweep gas contains CO2-enriched gas, and the sweep gas is recovered from the second effluent gas and used as a constituent component of the feed gas. Using CO2 from the CO2-enriched gas (in other words, CO2 from the CO2-containing gas) as a constituent component of the feed gas can contribute to the synthesis of carbon-neutral liquid fuel. The sweep gas preferably contains hydrogen as a major component. This allows the gas recovered from the second effluent gas to be reused as part of the feed gas without the need for further separation.

[0088] The liquid fuel or water and the remaining raw material gas are separated and recovered from the first effluent gas, and the remaining raw material gas is reused as part of the raw material gas in the step (III).

[0089] The reactor, catalyst, water vapor separation membrane, liquid fuel separation membrane, and sweep gas for producing liquid fuel are as described in Section A. [Industrial Applicability]

[0090] The liquid fuel production system and the liquid fuel production method according to the embodiment of the present invention can be suitably used for producing liquid fuel such as methanol. [Explanation of symbols]

[0091] 1A, 1B Liquid Fuel Production System 10 Carbon dioxide capture section 20 Liquid fuel synthesis department 30 Temperature control gas supply unit (sweep gas supply unit) 40 Temperature control gas circulation section (sweep gas circulation section) 50 Heat transfer medium supply section 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 section

Claims

1. a gas adsorption / desorption unit that adsorbs a predetermined gas A and desorbs it by heating; a heat transfer medium supply unit that supplies a heat transfer medium for heating the gas adsorption / desorption unit to the gas adsorption / desorption unit; a liquid fuel synthesis unit having a first gas flow path containing a catalyst for promoting a conversion reaction from a raw material gas containing at least carbon dioxide and hydrogen to a liquid fuel, and a second gas flow path through which a temperature control gas for adjusting the temperature of the first gas flow path flows, wherein a first effluent gas flows from the first gas flow path and a second effluent gas flows from the second gas flow path; a heat exchanger for exchanging heat between the first effluent gas and the heat transfer medium to heat the heat transfer medium; Equipped with the first effluent gas contains a condensable gas; Liquid fuel production system.

2. the gas adsorption / desorption unit is a carbon dioxide adsorption / desorption unit, The liquid fuel production system according to claim 1 , further comprising a carbon dioxide recovery unit having the carbon dioxide adsorption / desorption unit and recovering carbon dioxide-enriched gas from the carbon dioxide-containing gas.

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

4. the liquid fuel synthesis unit has a water vapor separation membrane between the first gas flow path and the second gas flow path, the water vapor permeable membrane being disposed between the first gas flow path and the second gas flow path; The liquid fuel production system of claim 1 , wherein the first effluent gas contains the liquid fuel.

5. the liquid fuel synthesis unit has a liquid fuel separation membrane between the first gas flow path and the second gas flow path, the liquid fuel separation membrane being permeable to at least the liquid fuel, The liquid fuel production system of claim 1 , wherein the first effluent gas contains water vapor that is a by-product of the shift reaction.

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

7. the temperature control gas contains the carbon dioxide enriched gas, The liquid fuel production system according to claim 2 , further comprising 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-enriched gas to the liquid fuel synthesis unit.

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

9. a step (I) of contacting a carbon dioxide-containing gas with a carbon dioxide adsorbent to adsorb the carbon dioxide onto the carbon dioxide adsorbent; a step (II) of desorbing the carbon dioxide from the carbon dioxide adsorbent by heating to recover a carbon dioxide-enriched gas; a step (III) of carrying out the conversion reaction using a liquid fuel synthesis unit having a first gas flow path containing a catalyst that promotes a conversion reaction from a feed gas containing at least carbon dioxide and hydrogen to a liquid fuel, and a second gas flow path through which a temperature control gas that adjusts the temperature of the first gas flow path flows, wherein a first effluent gas flows from the first gas flow path and a second effluent gas flows from the second gas flow path; a step (IV) of heating a heat transfer medium for heating the carbon dioxide adsorbent in the step (II) by heat exchange using the first effluent gas as a heat medium; Including, the first effluent gas contains a condensable gas; A method for producing liquid fuel.

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

11. the temperature control gas contains the carbon dioxide enriched gas, The method according to claim 9 , wherein carbon dioxide derived from the carbon dioxide-enriched gas is recovered from the second effluent gas and used as a constituent component of the raw material gas.

12. The method of claim 9 , wherein the heat transfer medium contains the carbon dioxide enriched gas.

13. the liquid fuel synthesis unit has a water vapor separation membrane between the first gas flow path and the second gas flow path, the water vapor permeable membrane being disposed between the first gas flow path and the second gas flow path; The method of claim 9 wherein the first effluent gas contains the liquid fuel.

14. the liquid fuel synthesis unit has a liquid fuel separation membrane between the first gas flow path and the second gas flow path, the liquid fuel separation membrane being permeable to at least the liquid fuel, 10. The process of claim 9, wherein the first effluent gas contains water vapor that is a by-product of the shift reaction.

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