Valuable product manufacturing method, valuable product manufacturing apparatus, and valuable product manufacturing system

Abstract

To provide a method for producing a valuable material, capable of effectively utilizing carbon dioxide separated from a gas containing a plurality of kinds of gas components.SOLUTION: According to an aspect of the present invention, there is provided a method for producing a valuable material, the method including a separation step of separating carbon dioxide and hydrogen from a gas containing carbon monoxide, carbon dioxide, and hydrogen, a first valuable material production step of producing a first valuable material from the gas from which carbon dioxide and hydrogen have been separated, using a microorganism, and a second valuable material production step of producing a second valuable material by reacting at least the separated carbon dioxide and the separated hydrogen using a catalyst.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for producing valuable materials, an apparatus for producing valuable materials, and a system for producing valuable materials. [Background technology]

[0002] In recent years, global environmental problems have arisen, such as concerns about the depletion of fossil fuel resources and the increase in atmospheric carbon dioxide due to the mass consumption of oils and alcohols produced from petroleum. To address these problems, methods for producing organic substances using raw materials other than petroleum, such as the production of bioethanol by sugar fermentation from edible raw materials such as corn, have attracted attention. Since sugar fermentation methods using edible raw materials like this require limited agricultural land to be used for non-food production, which could lead to a rise in food prices, methods are being considered to produce organic substances that were previously produced from petroleum using inedible raw materials that would otherwise be discarded.

[0003] For example, Patent Document 1 discloses a method for producing organic substances by supplying a gas having a higher carbon dioxide content than air, partially oxidizing a carbon source to produce a synthesis gas containing carbon monoxide, and fermenting this synthesis gas with microorganisms. Furthermore, in the method of Patent Document 1, carbon dioxide is separated from the synthesis gas, and the separated carbon dioxide is supplied to a synthesis furnace for synthesis gas. However, simply supplying (returning) the separated carbon dioxide to the synthesis furnace as is is not enough to effectively utilize the carbon dioxide. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-077120 Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above circumstances, the present invention provides a method for producing valuable materials that can effectively utilize carbon dioxide separated from a gas containing a plurality of gas components. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided a method for producing valuable materials, comprising: a separation step of separating carbon dioxide and separating hydrogen from a gas containing carbon monoxide, carbon dioxide, and hydrogen; a first valuable material generation step of generating a first valuable material using microorganisms from the gas from which the carbon dioxide and hydrogen have been separated; and a second valuable material generation step of reacting at least the separated carbon dioxide and the separated hydrogen using a catalyst to generate a second valuable material.

[0007] According to this embodiment, carbon dioxide separated from a gas containing a plurality of gas components can be effectively utilized. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram showing the configuration of a first embodiment of a valuable resource production system. [Figure 2] FIG. 10 is a schematic diagram showing the configuration of a second embodiment of a valuable resource production system. [Figure 3] FIG. 10 is a schematic diagram showing the configuration of a third embodiment of a valuable resource production system. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a method for producing valuable materials, an apparatus for producing valuable materials, and a system for producing valuable materials will be described in detail based on preferred embodiments shown in the accompanying drawings. First Embodiment First, a first embodiment of a valuable resource production system that can be used in a valuable resource production method will be described. FIG. 1 is a schematic diagram showing the configuration of a first embodiment of a valuable resource production system. The valuable resource production system 100 (hereinafter also simply referred to as "production system 100") shown in Fig. 1 includes a gasification furnace (gas generation unit that generates gas) 10, and a valuable resource production device 1 (hereinafter also simply referred to as "production device 1") connected to the gasification furnace 10. Note that in this specification, the upstream side with respect to the flow direction of gas and liquid will also be referred to simply as the "upstream side", and the downstream side will also be referred to simply as the "downstream side".

[0010] In this embodiment, the gasifier 10 is not particularly limited, but examples thereof include a fluidized bed furnace, a kiln furnace, a shaft furnace, etc. In addition to the gasifier 10, the gas generating unit may be a CO2 generator of at least one facility selected from a combustion furnace (incinerator), a paper mill, a cement factory, a thermal power plant, an oil refinery, an ethylene cracker, a refinery, a chemical plant, a blast furnace, a converter, or an electric furnace (electric furnace) in a steelworks. X It may also be an emission source. In each furnace, gases containing carbon monoxide, carbon dioxide and hydrogen (hereinafter also referred to as "raw material gases") are produced (generated) when the contents are burned, melted, refined, etc.

[0011] In the case of a combustion furnace or gasification furnace 10 in a waste incineration plant, the contents (waste) include, for example, plastic waste, food waste, municipal solid waste (MSW), industrial waste, discarded tires, biomass waste, household waste (futons, paper), building materials, etc. Note that these wastes may contain one type alone or two or more types. In addition, in the case of a blast furnace, converter, or electric furnace in a steelworks, for example, a raw material gas is generated (or produced) when iron ore is heated together with coke, limestone, etc. In the case of a chemical plant, for example, a raw material gas is generated (or produced) when methane is steam reformed.

[0012] The carbon in raw gas derived from waste, etc. is different from the carbon in petroleum. 14 C. 13 The abundance ratio of carbon isotopes such as C (e.g., δ 14 C, δ 13The carbon isotope ratios (values ​​of carbon) contained in valuable materials produced from such raw material gas by the production system 100 are different from those of valuable materials derived from petroleum. Therefore, even if valuable materials produced by the production system 100 are converted into other compounds and used, it is possible to determine (trace) that they originated from valuable materials produced by the production system 100 using a method with low environmental impact.

[0013] The raw material gas typically contains, in addition to carbon monoxide, carbon dioxide, and hydrogen, other gas components such as nitrogen, oxygen, water vapor, methane, etc. The raw material gas may further contain, as other components, soot, tar, nitrogen compounds, sulfur compounds, phosphorus-based compounds, aromatic compounds, etc. The raw material gas may be generated as a gas containing 10% by volume or more of carbon monoxide by subjecting the contents (carbon source) to a heat treatment (commonly known as gasification) that incompletely combusts the contents (carbon source) (i.e., by partially oxidizing the carbon source). If valuable materials are produced using such a raw material gas, carbon dioxide that has conventionally been emitted into the atmosphere can be effectively utilized, thereby reducing the burden on the environment. From the viewpoint of carbon circulation, it is preferable to use exhaust gas generated in a combustion furnace or a smelter as the raw material gas.

[0014] The gasifier 10 may have an oxygen generator that generates oxygen necessary for combustion. Examples of oxygen generators include cryogenic separation devices that compress, cool, and liquefy atmospheric air to extract liquefied oxygen, liquefied nitrogen, and the like. The heat absorbed when the resulting liquefied nitrogen evaporates can be used to cool parts of the production system 100. Furthermore, the nitrogen gas obtained by evaporating the liquefied nitrogen can be suitably used as a purge gas for various parts of the production system 100.

[0015] The gasifier 10 may also have a reforming area inside or outside thereof for reforming the raw material gas. In the reforming area, for example, the raw material gas is retained at a high temperature to convert hydrocarbons contained in the raw material gas (methane, ethane, char, tar, dioxins, etc.) into carbon monoxide and hydrogen. At this time, a combustion-supporting gas such as oxygen or air may be supplied to raise the temperature. Furthermore, a portion of the carbon monoxide may be converted to carbon dioxide by reacting with oxygen. The temperature is preferably 1000°C or higher, and more preferably 1100°C or higher and 1400°C or lower.

[0016] In the reforming area, a method may be adopted in which steam is reacted with hydrocarbons such as methane contained in the raw gas at high temperatures in the presence of a catalyst to convert them into carbon monoxide and hydrogen. At this time, part of the carbon monoxide may be further converted into carbon dioxide and hydrogen by reacting with the steam. The reaction temperature is preferably 500° C. or higher and 1200° C. or lower. Examples of the catalyst include metal catalysts, such as nickel catalysts, nickel oxide catalysts, ruthenium catalysts, rhodium catalysts, palladium catalysts, and platinum catalysts.

[0017] Here, the stable carbon isotope ratio δ 13 It is known that the value of δC tends to be high under high temperature combustion conditions and tends to be low under incomplete combustion. Therefore, by providing a reforming area, the raw material gas can be converted to a unique δC value according to the combustion conditions. 13 Therefore, even if the valuable material produced by the production system 100 is converted into another compound and used, it can be determined (traced) that it originated from the valuable material produced by the production system 100 using a method with low environmental impact.

[0018] The raw material gas (synthesis gas) generated by the gasifier 10 is at a high temperature. The heat of this high-temperature raw material gas may be used to generate steam from water. For example, a tank storing water may be provided in the gas line GL1 connected downstream of the gasifier 10, and steam may be generated by heat exchange between the raw material gas and the water. Alternatively, steam may be generated by heat exchange with the raw material gas using a heat recovery device (e.g., an economizer, a heat pump, etc.) that is more suitable for recovering high-temperature heat and provided near the gas line GL1 near the outlet of the gasifier 10. In this way, by efficiently recovering the heat of the raw material gas and utilizing it without waste, the environmental impact during the production of valuable materials can be further reduced. The heat of the raw material gas can be used for various purposes, not limited to the above purposes. Alternatively, the heat of the gas discharged from the reforming area may be recovered. When a scrubber is used for cooling, the heat recovery method may utilize the thermal energy recovered through the scrubber.

[0019] A manufacturing apparatus 1 is connected to the gasification furnace 10. The manufacturing apparatus 1 includes a culture tank (first valuable resource production unit) 2, a refinery 6, a gas line GL1 connecting the gasification furnace 10 and the culture tank 2, and a liquid line LL connecting the culture tank 2 and the refinery 6. In the culture tank 2, a first valuable resource is produced from the supplied raw material gas using microorganisms (particularly, gas-assimilating bacteria). That is, in the culture tank 2, the first valuable resource is produced by microbial fermentation of the raw material gas. The first valuable resource may be, for example, at least one of alcohols such as methanol and ethanol, organic acids such as acetic acid, and SAF (Sustainable Aviation Fuel).

[0020] Here, the first valuable material produced in the culture tank 2 is produced using carbon derived from the raw material gas, and therefore is different from the valuable material derived from petroleum. 14 C. 13 The abundance ratio of carbon isotopes such as C (e.g., δ 14 C, δ 13Therefore, even if this first valuable material is converted into a product such as another compound and used, it can be determined (traced) that it originates from the first valuable material produced by the manufacturing system 100 using a method with low environmental impact.

[0021] Examples of gas-utilizing bacteria include Butyribacterium methylotrophicum, Clostridium autoethanogenum, Clostridium carboxidivorans, Clostridium ljungdahlii, Clostridium ragsdalei, Moorella, and Carboxydothermus.

[0022] When a microorganism such as a gas-utilizing bacterium is used, the first valuable material 14 C. 13 The abundance ratio of carbon isotopes such as C (e.g., δ 14 C, δ 13 Therefore, even if the generated first valuable material is converted into another compound and used, it can be more easily determined (traced) that it is derived from the first valuable material generated by the production system 100 using a method with low environmental impact.

[0023] The medium (culture solution) used to culture gas-utilizing bacteria is not particularly limited as long as it has an appropriate composition depending on the type of bacteria. For example, when Clostridium bacteria are used as gas-utilizing bacteria, the medium can be determined by referring to, for example, paragraphs 0097 to 0098 of U.S. Patent Application Publication No. 2017 / 260552. The culture tank 2 can be, for example, a culture reactor of the type that stirs the culture solution with a stirring plate, a culture reactor of the type that stirs the culture solution by circulating the culture solution itself, or a culture reactor of the type that stirs the culture solution by a water flow accompanied by a bubble flow generated by aeration of the supplied exhaust gas.

[0024] The production apparatus 1 includes a pre-treatment section (separation section) 5 provided midway along the gas line GL1 (that is, between the gasification furnace 10 and the culture tank 2). This pretreatment section (separation section) 5 separates carbon dioxide and hydrogen from the raw material gas (gas containing carbon monoxide, carbon dioxide, and hydrogen). Specifically, the pretreatment section 5 has a PSA unit 51 and a dehydrogenation unit 52 arranged downstream of the PSA unit 51.

[0025] The PSA unit 51 is a pressure swing adsorption type separator, and is used to separate (remove) BTEX, carbon dioxide, nitrogen, and the like, for example. For example, porous materials such as activated carbon, zeolite, silica gel, and molecular sieves, or aqueous solutions such as amine solutions can be used as adsorbents in the PSA device 51. Activated carbon or zeolite is preferably used in the PSA device 51. By setting the type of porous material and the pore size, it is possible to select compounds that can be separated. When separating two or more compounds in the PSA device 51, multiple separators each filled with porous materials of different types or pore sizes may be used, or a single separator filled with porous materials of different types or pore sizes may be used.

[0026] The method for utilizing the carbon dioxide separated by the PSA device 51 will be described in detail later. The nitrogen separated in the PSA unit 51 may be filled into the culture tank 2 when culturing microorganisms (gas-assimilating bacteria), or may be filled for cleaning the PSA unit 51 and / or the TSA unit (if used). Nitrogen may be filled into only one of the above units, or two or more units. In this way, by removing nitrogen from the raw material gas, the volume of the raw material gas to be treated on the downstream side can be reduced, and therefore the pre-treatment unit 5 arranged on the downstream side can be made smaller.

[0027] The dehydrogenation unit 52 is mainly used to separate (remove) hydrogen from the raw material gas from which carbon dioxide and nitrogen have been separated (removed). The dehydrogenation device 52 can preferably be configured with a separator containing a separation membrane that selectively permeates and separates hydrogen. Examples of materials that can be used for such separation membranes include metal materials, ceramic materials, and resin materials. Examples of the metal material include Pd-Cu alloy, Pd-Ag alloy, vanadium alloy, and amorphous alloy such as La-Ni-Mg alloy. Examples of ceramic materials include titanium nitride, zeolite, silica (glass), alumina, and composite materials containing one or more of these (for example, alumina carbon-based materials). Examples of the resin material include polyamide, polyimide, and polysulfone.

[0028] The separation membrane is preferably made of a porous body having continuous pores (pores penetrating the cylindrical wall) in which adjacent pores are connected to each other. A separation membrane having such a configuration can separate hydrogen more smoothly and reliably. The porosity of the separation membrane is not particularly limited, but is preferably 10% to 90%, and more preferably 20% to 60%, which prevents the mechanical strength of the separation membrane from decreasing significantly while maintaining a sufficiently high hydrogen permeability. The shape of the separation membrane is not particularly limited, and examples thereof include cylindrical, rectangular, hexagonal and other rectangular tubular shapes. The average pore size of the separation membrane is preferably 500 pm or less, and more preferably 300 pm to 400 pm, which can further improve the hydrogen separation efficiency.

[0029] The pretreatment unit 5 may include, for example, a deoxidizer, a deacetylenizer, a TSA unit, a PTSA unit, etc. in addition to the PSA unit 51 and the dehydrogenation unit 52. These units may be used alone or in any combination, and the order in which they are arranged may also be arbitrary. The deoxidizer is used to remove oxygen and can be configured as a reactor filled with metal particles such as copper (Cu), platinum (Pt), nickel (Ni), etc. as an oxygen removal catalyst. The oxygen removal catalyst is preferably heated to, for example, 150°C or higher and 400°C or lower. The deacetyleneizer is used to remove acetylene, and can be configured with a reactor filled with particles of a noble metal such as palladium (Pd) or platinum (Pt) as an acetylene removal catalyst. By removing acetylene prior to deoxidation, there is an advantage that the adverse effect of acetylene on the oxygen removal catalyst can be suitably prevented or reduced.

[0030] The TSA unit is a temperature swing adsorption separator used to remove, for example, aromatic compounds other than BTEX. The PTSA unit is a pressure and temperature swing adsorption type separator, and is used, for example, to collectively remove the components removed by the PSA unit 51 and the TSA unit. The types of adsorbents and constituent materials used in the TSA and PTSA devices can be the same as those described for the PSA device 51.

[0031] The raw material gas treated in the pretreatment unit 5 is supplied to the culture tank 2. The concentration of carbon dioxide contained in the raw material gas supplied to the culture tank 2 is preferably 0.1 vol% or more and 30 vol% or less, more preferably 0.3 vol% or more and 25 vol% or less, even more preferably 0.5 vol% or more and 20 vol% or less, particularly preferably 0.8 vol% or more and 15 vol% or less, and most preferably 1 vol% or more and 10 vol% or less.

[0032] The concentration of carbon monoxide contained in the raw material gas supplied to the culture tank 2 is preferably 10% by volume or more and 90% by volume or less, more preferably 15% by volume or more and 70% by volume or less, and even more preferably 20% by volume or more and 45% by volume or less. Furthermore, the hydrogen concentration contained in the raw material gas supplied to the culture tank 2 is preferably 0.4 times or less, more preferably 0.35 times or less, and even more preferably 0.3 times or less, the hydrogen concentration contained in the raw material gas generated in the gasification furnace (gas generation unit) 10. Specifically, the hydrogen concentration contained in the raw material gas supplied to the culture tank 2 is preferably 1 volume % to 45 volume %, more preferably 5 volume % to 35 volume %, and even more preferably 5 volume % to 30 volume %. If the hydrogen and carbon dioxide contents in the raw material gas are reduced via a separation membrane or the like, it can be expected that the effect of suppressing variation over time in the overall composition of the treated gas can be suppressed.

[0033] Furthermore, the concentration of nitrogen contained in the raw material gas supplied to the culture tank 2 is preferably 30% by volume or less, more preferably 1% by volume or more and 25% by volume or less, and even more preferably 5% by volume or more and 20% by volume or less. According to the above configuration, a raw material gas with a low concentration of hydrogen is supplied to the culture tank 2, so that hydrogen is less likely to reduce the activity of microorganisms (gas-assimilating bacteria). In other words, hydrogen can be supplied at a concentration suitable for use by microorganisms, allowing the microorganisms to be active. Furthermore, since the raw material gas has an increased carbon monoxide concentration as a result of mainly carbon dioxide and nitrogen being separated (removed) in the PSA unit 51, the first valuable resource can be produced more efficiently in the culture tank 2. Furthermore, since the volume of the raw material gas as a whole is reduced, the size of the pretreatment unit 5 and / or the piping, pumps, containers, etc. arranged downstream thereof can also be reduced.

[0034] In the culture tank 2, a first valuable resource, specifically a valuable resource-containing liquid containing the first valuable resource, is produced from the raw material gas from which carbon dioxide and hydrogen have been separated using microorganisms (gas-assimilating bacteria). A refiner 6 is connected to the culture tank 2 via a liquid line LL. The refiner 6 is a device for purifying a first valuable material (organic substance) from the valuable material-containing liquid. Examples of such a refining device 6 include a distillation device, a treatment device including a pervaporation membrane, a zeolite dehydration membrane, a treatment device including an organic membrane, a treatment device for removing low-boiling substances having a boiling point lower than that of the first valuable material, a treatment device for removing high-boiling substances having a boiling point higher than that of the first valuable material, a treatment device including an ion exchange membrane, etc. These devices may be used alone or in combination of two or more.

[0035] When a distillation apparatus is used, the temperature inside the distillation apparatus during distillation when the first valuable material is, for example, ethanol is not particularly limited, but is preferably 100° C. or lower, and more preferably 70° C. or higher and 95° C. or lower. By setting the temperature in this range, separation of the necessary first valuable material from other components, i.e., distillation (purification) of the first valuable material can be more reliably carried out. The pressure inside the distillation apparatus during distillation of the first valuable material may be normal pressure, but is preferably lower than atmospheric pressure (reduced pressure distillation), and more preferably 60 kPaA or higher and 95 kPaA or lower. By setting the pressure in this range, the separation efficiency of the first valuable material can be improved, and thus the yield of the first valuable material can be improved. The yield of the first valuable product (the concentration of the first valuable product contained in the purified product) is preferably 90% by weight or more, more preferably 99% by weight or more, and even more preferably 99.5% by weight or more. Furthermore, when the first valuable product is, for example, acetic acid, the temperature inside the distillation apparatus during distillation is not particularly limited, but is preferably 95°C or higher, and more preferably 100°C or higher and 150°C or lower. The pressure inside the distillation apparatus during distillation of the first valuable material may be normal pressure, but is preferably less than atmospheric pressure (reduced pressure distillation), more preferably 60 kPaA or more and 95 kPaA or less. By setting the pressure in this range, the separation efficiency of the first valuable material can be improved, and ultimately the yield of the first valuable material can be improved. In addition, an azeotropic agent or the like may be added to the valuable material-containing liquid.

[0036] Examples of the first valuable product thus obtained include monools such as methanol and ethanol, diols such as 2,3-butanediol, acetic acid, lactic acid, isoprene, butadiene, etc., and are preferably monools or diols having 1 to 4 carbon atoms, and more preferably ethanol. Such a first valuable resource can be used, for example, as a raw material for resin materials, rubber materials, etc., and can also be used as various solvents, disinfectants, or fuel. High-concentration ethanol can be used as fuel ethanol to be mixed with gasoline, etc., and can also be used, for example, as a raw material for cosmetics, beverages, chemicals, fuel (jet fuel), etc., and as an additive for foods, etc., making it extremely versatile.

[0037] The production apparatus 1 includes a synthesis section (second valuable material production section) 7 connected to the PSA unit 51 via a gas line GL2 and to the dehydrogenation unit 52 via a gas line GL3. In the synthesis section 7, at least the carbon dioxide separated in the PSA unit 51 and the hydrogen separated in the dehydrogenation unit 52 are reacted using a catalyst to generate a second valuable product. The second valuable product preferably contains at least one selected from the group consisting of amino acids, aliphatic hydrocarbons, alcohols, ketones, and carboxylic acids.

[0038] Examples of catalysts capable of producing amino acids as second valuable products include metalloporphyrin-based catalysts, metal-organic frameworks (MOFs), metal or alloy catalysts containing gold, copper, ruthenium, etc., microbial catalysts such as purple photosynthetic bacteria, and ceramic catalysts such as oxide-based catalysts containing cerium oxide and zirconium oxide. Examples of catalysts capable of producing aliphatic hydrocarbons as second valuables include metal or alloy catalysts containing copper, iron, etc., oxide catalysts containing cerium oxide, titanium oxide, etc., composite catalysts containing any combination of the above metal or alloy catalysts and the above oxide catalysts, metal complex catalysts containing ruthenium, etc., organic group-modified zeolite catalysts, and petroleum-metabolizing bacteria.

[0039] Examples of catalysts capable of producing alcohol as a second valuable product include metal or alloy catalysts containing copper, silver, nickel, zinc, zirconium, etc.; oxide catalysts containing zinc oxide, titanium oxide, etc.; composite catalysts containing any combination of the above metal or alloy catalysts and the above oxide catalysts; carbon-supported catalysts in which metal nanoparticles are supported on a carbon material; and metal complex catalysts containing iridium, etc. Among these, a palladium-molybdenum intermetallic compound catalyst is suitable as a catalyst capable of producing methanol as a second valuable product. This catalyst can produce methanol from carbon dioxide and hydrogen at extremely low temperatures (room temperature).

[0040] Examples of catalysts capable of producing ketones as second valuables include metal or alloy catalysts containing palladium, ruthenium, etc., oxide catalysts containing titanium dioxide, etc., and composite catalysts containing any combination of the above metal or alloy catalysts and the above oxide catalysts. Examples of catalysts capable of producing carboxylic acid as the second valuable product include metal organic frameworks (MOFs) containing copper, zirconium, etc.; metal or alloy catalysts containing palladium, ruthenium, rhodium, etc.; oxide catalysts containing titanium dioxide, etc.; composite catalysts containing any combination of the above metal or alloy catalysts and the above oxide catalysts; and alkyllithium compounds.

[0041] Further, a removal unit 8 may be provided midway along each of the gas lines GL2 and GL3. The removal unit 8 has a function of removing impurities contained in the gas separated (recovered) from the PSA unit 51 or the dehydrogenation unit 52, which impair the reactivity of the catalyst. If the separation selectivity of hydrogen and carbon monoxide is high and separated carbon dioxide and separated hydrogen can be obtained with high purity, removal unit 8 does not need to be provided. Such impurities include, but are not limited to, sulfur or sulfur compounds, chlorine or chlorine compounds, cyanide compounds, etc. Among these, it is preferable to remove sulfur compounds, especially hydrogen sulfide, as impurities. Removal of hydrogen sulfide can suitably prevent the catalyst from being significantly reduced in reactivity or deactivated.

[0042] The removal section 8 can be configured, for example, by a reactor filled with a desulfurizing agent. Examples of the desulfurizing agent include an iron oxide-based desulfurizing agent, an activated carbon-based desulfurizing agent, a copper-zinc-based desulfurizing agent, a copper-zinc-aluminum-based desulfurizing agent, and a lime-based desulfurizing agent. If an iron oxide-based desulfurizing agent is used, the iron sulfide produced by the reaction with hydrogen sulfide can react with oxygen, so oxygen can also be removed from the gas passing through the gas lines GL2 and GL3. After the gas line GL2 and the gas line GL3 are joined, the removal unit 8 may be provided midway along the joined gas line.

[0043] Next, a method of using the manufacturing system 100 of the first embodiment (a method of manufacturing valuable resources) will be described. [1] First, the raw material gas (gas containing carbon monoxide, carbon dioxide, hydrogen, and other gas components) discharged from the gasification furnace 10 is supplied to the pretreatment section 5. In the pretreatment section 5, BTEX, carbon dioxide, nitrogen, etc. are removed (separated) from the raw material gas by a PSA device 51, and then hydrogen is removed (separated) by a dehydrogenation device 52 (separation step). In this embodiment, in this step [1] (separation step), hydrogen is preferably separated from the raw material gas using a separation membrane such as described above. Furthermore, in the pretreatment section 5, for example, water-soluble substances, soot, fine particles smaller than soot, oxygen, acetylene, aromatic compounds other than BTEX, etc. may be removed from the raw material gas. In the hydrogen separation step, for example, if there is surplus hydrogen, it may be stored. Also, if the amount of hydrogen removed is excessive and the amount of hydrogen introduced into the culture tank 2 is insufficient, the removed hydrogen may be introduced into the culture tank. The carbon dioxide may also be stored or introduced into the culture tank 2 in the same manner.

[0044] [2] Next, the raw material gas that has passed through the pretreatment unit 5 is supplied to the culture tank 2. In the culture tank 2, a first valuable material, specifically a valuable material-containing liquid containing the first valuable material, is produced from the raw material gas from which carbon dioxide and hydrogen have been separated using microorganisms (by the action of gas-assimilating bacteria) (first valuable material production step). Here, the temperature at which the valuable resource-containing liquid is produced in the culture tank (first valuable resource production section) 2 is preferably 25°C or higher and 50°C or lower, more preferably 30°C or higher and 45°C or lower, and even more preferably 35°C or higher and 40°C or lower. When producing a valuable resource-containing liquid in the culture tank 2, the nitrogen removed (separated) by the PSA device 51 may be filled into the culture tank 2. In this case, the concentration of oxygen contained in the space inside the culture tank 2 can be relatively reduced, and adverse effects of oxygen on microorganisms (gas-assimilating bacteria) can be prevented or reduced.

[0045] [3] Next, the valuable material-containing liquid produced in the culture tank 2 is supplied to the refinery 6 via the liquid line LL. In the refinery 6, the first valuable material contained in the valuable material-containing liquid is refined to obtain a refined product containing the first valuable material at a high concentration. [4] Meanwhile, the gas containing carbon dioxide and the like separated in the PSA unit 51 is supplied to the synthesis unit 7 via a gas line GL2. In addition, the gas mainly containing hydrogen separated in the dehydrogenation unit 52 is supplied to the synthesis unit 7 via a gas line GL3. At this time, the gas flowing through the gas lines GL2 and GL3 passes through the removal section 8, whereby sulfur compounds (particularly hydrogen sulfide) are removed, thereby preventing or suppressing a decrease in the activity of the catalyst in the synthesis section 7.

[0046] In the synthesis section (second valuable product generation section) 7, at least the separated carbon dioxide and the separated hydrogen are reacted using a catalyst to generate a second valuable product (second valuable product generation step). As described above, the second valuable material preferably includes at least one selected from the group consisting of carbon monoxide, amino acids, alkanes, alkenes, alcohols, ketones, and carboxylic acids. Furthermore, in the synthesis unit 7, other valuable materials may be synthesized from carbon monoxide. For example, when producing methanol as a second valuable product, if a palladium-molybdenum intermetallic compound catalyst is used as the catalyst, methanol can be efficiently produced from carbon dioxide and hydrogen under pressurized conditions (e.g., about 0.9 MPa) and room temperature (e.g., about 25°C).

[0047] Such second valuable resources can be used, for example, as raw materials for resin materials, rubber materials, cosmetics, beverages, etc., or as additives for foods, etc. According to the above-described configuration, the separated carbon dioxide can be converted into the second valuable resource, and therefore the carbon dioxide can be effectively utilized. Furthermore, the raw material gas supplied to step [1A] (separation step) may be generated by feeding a substance containing the second valuables into a gas generation unit (for example, gasification furnace 10) and combusting this substance in the gas generation unit. Here, examples of the substance containing the second valuables include the above-mentioned resin materials, rubber materials, cosmetics, beverages, foods, etc.

[0048] The gas supplied to step [1] (separation step) may be generated by feeding waste containing the second valuables into a gas generating unit (e.g., gasifier 10) and burning the waste in the gas generating unit. Here, examples of waste containing the second valuables include waste from articles made of the above-mentioned resin materials and rubber materials, waste from cosmetics, beverages, and food. Furthermore, the second valuable material obtained in step [4] (second valuable material generation step) may be used as fuel for combustion in the above step [1] (separation step).

[0049] Furthermore, if the gas production unit (e.g., gasifier 10) becomes inoperable due to some influence, it becomes difficult to continuously supply the raw material gas to the first valuable resource production unit (e.g., culture tank 2), which may result in the death of the microorganisms. Therefore, in this case, it is advisable to incompletely combust the second valuable resource (e.g., methanol) to serve as a carbon monoxide supply source for the microorganisms. The hydrogen supply source for the microorganisms may be hydrogen separated in a separation unit (e.g., dehydrogenation device 52) or separately prepared hydrogen. As described above, by increasing the efficiency of reuse of the secondary valuable resource itself, carbon dioxide can be utilized more effectively.

[0050] If heating is required for the reaction in step [4] (second valuable resource generation step), this reaction may be carried out using the heat generated during the combustion in step [1]. In this case, the heat generated by the combustion can be effectively utilized without being wasted. For example, gas lines GL2 and GL3 may be arranged close to the gas line GL1 near the outlet of the gasifier 10, and heat exchange may be performed between the high-temperature raw material gas discharged from the gasifier 10 and the gas flowing through the gas lines GL2 and GL3. In this case, the reaction in step [4] (second valuable product production step) is performed at a temperature that is set appropriately depending on the type of catalyst, but is preferably performed at a temperature of 50°C or higher, more preferably at a temperature of 70°C or higher, and even more preferably at a temperature of 90°C or higher and 150°C or lower. This makes it easier to increase the yield of the second valuable product.

[0051] Second Embodiment Next, a second embodiment of the valuable resource production system will be described. The valuable resource manufacturing system of the second embodiment will be described below, focusing on the differences from the valuable resource manufacturing system of the first embodiment, and a description of similar points will be omitted. FIG. 2 is a schematic diagram showing the configuration of a second embodiment of a valuable resource production system.

[0052] The manufacturing system 100 of the second embodiment is similar to the manufacturing system 100 of the first embodiment except for the configuration of the pre-processing unit 5. The pretreatment unit 5 shown in FIG. 2 has a carbon dioxide removal unit 53 provided upstream of the PSA unit 51 (between the PSA unit 51 and the gasification furnace 10). By providing the carbon dioxide removal device 53 upstream of the PSA device 51, it is possible to further reduce the concentration of carbon dioxide contained in the raw material gas supplied to the culture tank 2. As a result, it is possible to further increase the production efficiency of the first valuable material.

[0053] This carbon dioxide removal device 53 can be configured not only by a device with a configuration similar to the above-mentioned PSA device 51 or TSA device, but also by, for example, a PTSA device (a pressure and temperature swing adsorption type separator), a low-temperature separation type (cryogenic type) separator, a membrane separation type separator, an amine absorption type separator, an amine adsorption type separator, etc. A commercially available product of the carbon dioxide removal device 53 is, for example, a reduced pressure steam swing type CO2 recovery device (manufactured by JCCL Corporation, "VPSA1") or the like. Among these, a membrane separation type separator is preferred for the carbon dioxide removal device 53. In this case, both carbon dioxide and hydrogen are separated from the raw material gas using a separation membrane in the raw material gas treatment process (separation process) in the pretreatment section 5. Devices using separation membranes are preferred because they are relatively inexpensive and can prevent or suppress increases in size and complexity. Devices using separation membranes are also preferred because they have a simple structure and are easy to maintain.

[0054] According to the manufacturing system 100 of the second embodiment, the same actions and effects as those of the manufacturing system 100 of the first embodiment can be obtained. In particular, in the second embodiment, since the carbon dioxide removal device 53 is separately provided, the concentration of carbon dioxide contained in the raw material gas can be reduced, thereby increasing the efficiency of producing the first valuable material. Also, the concentration of carbon dioxide contained in the separated (recovered) gas can be increased, thereby increasing the efficiency of producing the second valuable material. In other words, the production efficiency of the valuable material can be increased in the entire production system 100. In the second embodiment, the synthesis section 7 is connected to the carbon dioxide removal device 53 via a gas line GL2.

[0055] Third Embodiment Next, a third embodiment of a valuable resource production system will be described. The valuable resource manufacturing system of the third embodiment will be described below, focusing on the differences from the valuable resource manufacturing systems of the first and second embodiments, and omitting a description of similar points. FIG. 3 is a schematic diagram showing the configuration of a third embodiment of a valuable resource production system.

[0056] The manufacturing system 100 of the third embodiment is similar to the manufacturing system 100 of the first embodiment except for the configuration of the pre-processing unit 5. The pretreatment unit 5 shown in FIG. 3 has a dust removal unit 54 provided upstream of the PSA unit 51 (between the PSA unit 51 and the gasification furnace 10). By providing the dust removal device 54 upstream of the PSA unit 51, that is, by providing a step of removing soot generated during combustion in the gasification furnace 10 from the raw material gas prior to the above step [1] (separation step), the amount of dust brought into the PSA unit 51 and the dehydrogenation unit 52 can be reduced, thereby reducing the maintenance costs of the PSA unit 51 and the dehydrogenation unit 52. Furthermore, since the amount of dust contained in the raw material gas supplied to the culture tank 2 can be reduced, it is less likely to have an adverse effect on the microorganisms, and the production efficiency of the first valuable material can also be increased.

[0057] The dust removal device 54 can be configured, for example, by a wet washing tower, a filter, or the like. Wet scrubbers are so-called scrubbers, and are used to remove pollutants contained in exhaust gases (for example, soot and compounds having a benzene ring (e.g., naphthalene)), water-soluble substances, etc. In wet scrubbers, removal is carried out by bringing a cleaning liquid into contact with the material to be removed (wet cleaning method). An example of a wet cleaning method is a cleaning method using a water curtain. Examples of cleaning liquids include water, acidic solutions, and alkaline solutions. Among these, water is preferred as the cleaning liquid. The temperature of the cleaning liquid is usually 40°C or lower, preferably 30°C or lower, more preferably 25°C or lower, and even more preferably 15°C or lower.

[0058] The filter is used to remove particles smaller than the size of soot, and may be, for example, a bag filter. According to the manufacturing system 100 of the third embodiment, the same actions and effects as those of the manufacturing system 100 of the first embodiment can be obtained. In particular, in the third embodiment, a separate dust removal device 54 is provided, thereby reducing the amount of dust contained in the raw material gas, making it less likely to have an adverse effect on each part of the manufacturing system 100, and improving the manufacturing efficiency of valuable materials. Furthermore, it may be provided in the following aspects.

[0059] (1) A method for producing valuable materials, comprising: a separation step of separating carbon dioxide and separating hydrogen from a gas containing carbon monoxide, carbon dioxide, and hydrogen; a first valuable material generation step of generating a first valuable material from the gas from which the carbon dioxide and the hydrogen have been separated using a microorganism; and a second valuable material generation step of reacting at least the separated carbon dioxide and the separated hydrogen using a catalyst to generate a second valuable material.

[0060] (2) The method for producing valuable materials described in (1) above, wherein the second valuable material comprises at least one selected from the group consisting of carbon monoxide, amino acids, alkanes, alkenes, alcohols, ketones, and carboxylic acids.

[0061] (3) The method for producing valuable materials according to (1) or (2) above, wherein in the separation step, at least one of the carbon dioxide and the hydrogen is separated from the gas using a separation membrane.

[0062] (4) A method for producing valuable resources according to any one of (1) to (3) above, wherein the gas supplied to the separation process is produced by burning a substance containing the second valuable resource.

[0063] (5) In the method for producing valuable materials described in any one of (1) to (4) above, the gas supplied to the separation process is produced by burning waste containing the second valuable material.

[0064] (6) A method for producing valuable resources according to (4) or (5) above, wherein the reaction in the second valuable resource generation step is carried out using heat generated during the combustion.

[0065] (7) The method for producing valuable materials according to any one of (4) to (6) above, further comprising, prior to the separation step, a step of removing soot generated during the combustion from the gas.

[0066] (8) The method for producing valuable resources according to any one of (4) to (7) above, wherein the second valuable resources obtained in the second valuable resource generation step are used as fuel for the combustion.

[0067] (9) The method for producing valuable resources according to any one of (1) to (8) above, wherein the reaction in the second valuable resource generation step is carried out at a temperature of 50°C or higher.

[0068] (10) A valuable resource manufacturing apparatus comprising: a separation unit that separates carbon dioxide and hydrogen from a gas containing carbon monoxide, carbon dioxide, and hydrogen, and separates the carbon dioxide and hydrogen; a first valuable resource generation unit that generates a first valuable resource using microorganisms from the gas from which the carbon dioxide and hydrogen have been separated; and a second valuable resource generation unit that generates a second valuable resource by reacting at least the separated carbon dioxide and the separated hydrogen using a catalyst.

[0069] (11) A valuable resource production system comprising a gas generating unit that generates a gas containing carbon monoxide, carbon dioxide, and hydrogen, and the valuable resource production device described in (10) above. Of course, this is not the case.

[0070] As described above, various embodiments of the present invention have been described, but these are presented as examples and do not limit the scope of the invention in any way. The novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. Such embodiments and their modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the inventions and their equivalents as set forth in the claims.

[0071] For example, the valuable material manufacturing system and valuable material manufacturing apparatus may each have any other additional configuration compared to the above embodiments, may be replaced with any configuration that performs similar functions, or some configurations may be omitted. Furthermore, the valuable resource manufacturing systems and valuable resource manufacturing devices of the first to third embodiments may be combined in any desired configuration. Furthermore, in the first to third embodiments, carbon dioxide and hydrogen are separated from the raw material gas in different devices, but carbon dioxide and hydrogen may be separated from the raw material gas in the same device. [Explanation of symbols]

[0072] 100: Valuable material production system 10: Gasification furnace 1: Valuable material manufacturing equipment 2:Culture tank 5: Preprocessing section 51:PSA device 52: Dehydrogenation equipment 53: Carbon dioxide removal device 54: Dust removal equipment 6: Purification equipment 7: Synthesis section 8:Removal section GL1: Gas line GL2: Gas line GL3: Gas line LL: Liquid line

Claims

1. A method for producing valuable materials, a separation step of separating the carbon dioxide and the hydrogen from a gas containing carbon monoxide, carbon dioxide, and hydrogen; a first valuable material generating step of generating a first valuable material using a microorganism from the gas from which the carbon dioxide and the hydrogen have been separated; a second valuable resource production step of reacting at least the separated carbon dioxide and the separated hydrogen using a catalyst to produce a second valuable resource.

2. The method for producing valuable resources according to claim 1, The method for producing a valuable resource, wherein the second valuable resource comprises at least one selected from the group consisting of carbon monoxide, amino acids, alkanes, alkenes, alcohols, ketones, and carboxylic acids.

3. The method for producing valuable resources according to claim 1, In the separation step, at least one of the carbon dioxide and the hydrogen is separated from the gas using a separation membrane.

4. The method for producing valuable resources according to claim 1, A method for producing valuable resources, wherein the gas supplied to the separation step is produced by burning a substance containing the second valuable resource.

5. The method for producing valuable resources according to claim 1, A method for producing valuable materials, wherein the gas supplied to the separation step is produced by burning waste containing the second valuable materials.

6. The method for producing valuable resources according to claim 4, The method for producing valuable resources, wherein the reaction in the second valuable resource production step is carried out using heat generated during the combustion.

7. The method for producing valuable resources according to claim 4, The method for producing valuable materials further comprises, prior to the separation step, a step of removing soot generated during the combustion from the gas.

8. The method for producing valuable resources according to claim 4, The method for producing valuable resources, wherein the second valuable resources obtained in the second valuable resource generation step are used as fuel for the combustion.

9. The method for producing valuable resources according to claim 1, The method for producing valuable resources, wherein the reaction in the second valuable resource production step is carried out at a temperature of 50°C or higher.

10. A valuable resource manufacturing device, a separation unit that separates the carbon dioxide and the hydrogen from a gas containing carbon monoxide, carbon dioxide, and hydrogen; a first valuable resource generation unit that generates a first valuable resource using microorganisms from the gas from which the carbon dioxide and the hydrogen have been separated; a second valuable resource production unit that reacts at least the separated carbon dioxide and the separated hydrogen using a catalyst to produce a second valuable resource;

11. A valuable material production system, a gas generating unit that generates a gas containing carbon monoxide, carbon dioxide, and hydrogen; A valuable resource production system comprising the valuable resource production device according to claim 10.

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