Hydrogen production method and hydrogen production device

Abstract

Provided is a hydrogen production method that reduces the amount of carbon dioxide emitted outside a system.　The hydrogen production method includes: a dry modified reaction that obtains a syn-gas that includes carbon monoxide and hydrogen, from a raw material gas that includes methane and carbon dioxide, in the presence of a dry modified catalyst; a solid carbon capture reaction in which the syn-gas is reacted in the presence of a solid carbon capture catalyst, solid carbon is generated from the carbon monoxide in the syn-gas, and the solid carbon and processed gas are obtained; and the separation of the processed gas into outgas and hydrogen and the acquisition of hydrogen. The content molar ratio of the carbon monoxide content relative to the carbon dioxide content in the syn-gas, CO / CO2, the reaction temperature T1 (°C) of the dry modified reaction, and the reaction temperature T2 (°C) of the solid carbon capture reaction fulfill condition (1).　

Description

Hydrogen production method and hydrogen production device

[0001] The present invention relates to a hydrogen production method and a hydrogen production device.

[0002] A dry reforming (DRM) method is known in which methane and carbon dioxide are reacted to convert them into a synthesis gas containing carbon monoxide and hydrogen. ４ +CO ２ → 2CO + 2H ２ ) can be converted into a solid carbon deposition reaction (CH ４ →C+2H ２ , 2CO → C + CO ２ ), and this carbon deposition can reduce the catalytic activity of the catalyst (coking).

[0003] As one of the solutions to the above problem, a method is being developed in which the dry reforming reaction and the solid carbon capture reaction are carried out continuously using separate catalysts, thereby suppressing catalyst deterioration and enabling long-term operation. ２ O ３ and a stainless steel tube as a catalyst for capturing solid carbon, and a system in which these are connected in sequence is described.

[0004] Journal of CO2 Utilization, 2017, vol. 22, p. 91-96

[0005] In order to apply the system described in Non-Patent Document 1 to hydrogen production, the present inventors have devised an apparatus that adds a hydrogen separator to the above system, and have been developing a method that can continuously extract hydrogen using methane and carbon dioxide as raw materials.

[0006] As a result, it was discovered for the first time that although the above-mentioned method can continuously produce hydrogen (hydrogen gas), simply combining the three steps of the dry reforming reaction, the solid carbon capture reaction, and the hydrogen separation may result in more carbon dioxide being discharged outside the reaction system than is contained in the raw material gas introduced into the reaction system.

[0007] In the use of hydrogen, reducing carbon dioxide emissions during the production process is considered to be one of the important issues. Therefore, an object of the present invention is to provide a hydrogen production method in which carbon dioxide emissions to the outside of the system are reduced. Another object of the present invention is to provide a hydrogen production device.

[0008] As a result of extensive research into achieving the above object, the present inventors have found that the above object can be achieved by the following configuration.

[0009] [1] A method for producing a synthesis gas containing carbon monoxide and hydrogen from a raw material gas containing methane and carbon dioxide in the presence of a dry reforming catalyst, comprising: performing a dry reforming reaction to produce a synthesis gas containing carbon monoxide and hydrogen from the raw material gas containing methane and carbon dioxide; performing a solid carbon capture reaction to react the synthesis gas in the presence of a solid carbon capture catalyst to produce solid carbon from the carbon monoxide in the synthesis gas and obtain the solid carbon and a treated gas; and separating the treated gas into an exhaust gas and hydrogen to obtain hydrogen, wherein a CO / CO molar ratio of the carbon monoxide content to the carbon dioxide content in the synthesis gas is ２ and the reaction temperature T of the dry reforming reaction. １ (°C), and the reaction temperature T of the solid carbon capture reaction ２ (°C) and the following condition (1): [2] The reaction temperature T ２ [3] The hydrogen production method according to [1], wherein the temperature is equal to or higher than the activation temperature of the solid carbon capture catalyst. ４ / CO ２ [4] The method for producing hydrogen according to [1] or [2], wherein the reaction temperature T １ [5] The method for producing hydrogen according to any one of [1] to [3], wherein the reaction temperature T １

[0023] The method for producing hydrogen according to any one of [1] to [4], wherein the temperature is 600°C or higher. [6] The method for producing hydrogen according to any one of [1] to [5], further comprising recovering heat from the exhaust gas and using the heat for at least one reaction selected from the group consisting of the dry reforming reaction and the solid carbon capture reaction. [7] The method for producing hydrogen according to [6], wherein the recovery is performed by introducing the exhaust gas into a fuel cell. [8] The method for producing hydrogen according to [6], wherein the recovery is performed by combusting the exhaust gas. [9] The method for producing hydrogen according to any one of [1] to [8], wherein the separation of the treated gas is performed using a hydrogen separation membrane.

[10] A dry reforming reactor that performs a dry reforming reaction in the presence of a dry reforming catalyst to obtain a synthesis gas containing carbon monoxide and hydrogen from a raw material gas containing methane and carbon dioxide; a solid carbon collector that performs a solid carbon collection reaction that reacts the synthesis gas in the presence of a solid carbon collection catalyst to produce solid carbon from the carbon monoxide in the synthesis gas and obtain the solid carbon and a treated gas; a hydrogen separator that separates the treated gas into an exhaust gas and hydrogen; and a reaction temperature T １ a first temperature controller for adjusting the reaction temperature T (°C) of the solid carbon capture reaction; ２ (°C), a raw material gas regulator that adjusts the composition of the raw material gas, and a control device, wherein the control device adjusts a CO / CO molar ratio of the carbon monoxide content to the carbon dioxide content in the synthesis gas. ２ and the reaction temperature T １ and the reaction temperature T ２ and satisfy the following condition (1):

[11] The hydrogen production apparatus controls the first temperature regulator, the second temperature regulator, and the raw material gas regulator so as to satisfy the following:

[11] The control device controls the CH ４ / CO ２

[12] The hydrogen production apparatus according to

[10] , wherein the control device controls the first temperature regulator and the second temperature regulator to adjust the reaction temperature T １ is controlled to a temperature equal to or higher than the activation temperature of the dry reforming catalyst, and the reaction temperature T ２to a temperature equal to or higher than the activation temperature of the solid carbon capture catalyst.

[13] The hydrogen production device according to any one of

[10] to

[12] , further comprising a heat recovery device for recovering heat from the exhaust gas.

[14] The hydrogen production device according to

[13] , wherein the heat is used to heat at least one selected from the group consisting of the dry reforming reactor and the solid carbon capture device.

[15] The hydrogen production device according to any one of

[10] to

[14] , wherein the hydrogen separator includes a hydrogen separation membrane.

[16] The hydrogen production device according to

[13] , wherein the heat recovery device includes a fuel cell.

[17] A hydrogen production method comprising: a dry reforming reaction step of obtaining a synthesis gas containing carbon monoxide and hydrogen from a feed gas containing methane and carbon dioxide in the presence of a dry reforming catalyst; a solid carbon collection step of introducing the synthesis gas from the dry reforming reaction step and generating solid carbon from the carbon monoxide in the synthesis gas in the presence of a solid carbon collection catalyst to obtain a treated gas; and a hydrogen separation step of extracting hydrogen from the treated gas from the solid carbon collection step to obtain an exhaust gas containing carbon dioxide, wherein the exhaust gas from the hydrogen separation step is introduced into the dry reforming reaction step to circulate the carbon dioxide without discharging it to the outside.

[18] The hydrogen production method according to

[17] ,

[19] The hydrogen production method according to

[17] or

[18] , further comprising extracting and combusting a portion of the hydrogen separated in the hydrogen separation step, and supplying the generated heat to the dry reforming reaction step.

[20] The hydrogen production method according to any one of

[17] to

[19] , further comprising recovering heat from the exhaust gas from the hydrogen separation step and supplying the heat to the dry reforming reaction step before introducing the exhaust gas into the dry reforming reaction step.

[21] A hydrogen production apparatus comprising: a dry reforming reactor that obtains a synthesis gas containing carbon monoxide and hydrogen from a raw material gas containing methane and carbon dioxide in the presence of a dry reforming catalyst; a solid carbon collector that receives the synthesis gas from the dry reforming reactor and generates solid carbon from the carbon monoxide in the synthesis gas in the presence of a solid carbon collection catalyst to obtain a treated gas; a hydrogen separator that extracts hydrogen from the treated gas from the solid carbon collector to obtain an exhaust gas containing carbon dioxide; a first flow path that supplies the synthesis gas from the dry reforming reactor to the solid carbon collector, a second flow path that supplies the treated gas from the solid carbon collector to the hydrogen separator, and a third flow path that supplies the exhaust gas from the hydrogen separator to the dry reforming reactor, wherein carbon dioxide is circulated internally without being discharged to the outside.

[22] The hydrogen production apparatus according to

[21] , further comprising a methane combustion furnace and a heat supply flow path that supplies heat from the methane combustion furnace to the dry reforming reactor.

[23] The hydrogen production device according to

[21] or

[22] , further comprising a hydrogen extraction flow path that extracts a portion of the hydrogen from the hydrogen separator, a hydrogen combustion furnace that combusts the extracted hydrogen, and a heat supply flow path that supplies heat from the hydrogen combustion furnace to the dry reforming reaction path.

[24] The hydrogen production device according to any one of

[21] to

[23] , further comprising a heat recovery device that recovers heat from the exhaust gas connected to the third flow path, and the heat recovered by the heat recovery device is supplied to the dry reforming reactor.

[25] The hydrogen production device according to any one of

[21] to

[24] , further comprising a compressor in the first flow path.

[26] The hydrogen production device according to

[25] , further comprising a heat exchanger that converts heat generated in the solid carbon collector into steam and supplies the steam to the compressor.

[27] The hydrogen production device according to

[25] , further comprising a pressure regulating valve at the inlet of the hydrogen separator, and a gas holder and a pressure regulating valve at the outlet of the hydrogen separator.

[28] The hydrogen production device according to any one of

[21] to

[27] , further comprising a water supply passage for supplying water generated in the dry reforming reactor to the solid carbon collector.

[29] The hydrogen production device according to

[28] , further comprising a compressor in the first flow path, and further comprising a steam supply path for supplying steam generated in the solid carbon collector to the compressor.

[30] The hydrogen production device according to any one of

[21] to

[29] , further comprising a compressor in the first flow path, the first flow path downstream of the compressor is branched to arrange a plurality of the solid carbon collectors in parallel, and valves are provided at the inlet and outlet of each solid carbon collector.

[31] The hydrogen production device according to

[30] , further comprising a buffer tank in the first flow path downstream of the compressor and upstream of the branch.

[32] The hydrogen production device according to any one of

[21] to

[31] , further comprising a compressor in the first flow path, the plurality of solid carbon collectors are arranged in series, and a gas composition adjustment unit is provided between each solid carbon collector.

[0010] According to the present invention, a hydrogen production method can be provided in which the amount of carbon dioxide discharged outside the system is reduced. Typically, a hydrogen production method can be provided in which the amount of carbon dioxide discharged outside the system is less than the amount of carbon dioxide introduced into the system. Furthermore, according to the present invention, a hydrogen production apparatus can also be provided.

[0011] 1 is a block diagram of one embodiment of a hydrogen production apparatus that can be used to carry out the production method of the present invention. ２ + C). １ , reaction temperature T ２ , and CO / CO in the synthesis gas ２ The graph shows the relationship between the reaction temperature T １ 1 is a graph showing the relationship between CH ４ / CO ２ and CO / CO in the synthesis gas ２ The relationship between the reaction temperature T １FIG. 1 is a diagram showing dependency. FIG. 2 is a flow diagram of the hydrogen production method of the present invention. FIG. 3 is a block diagram of a first embodiment of the hydrogen production device of the present invention. FIG. 4 is a flow diagram of hydrogen production by the hydrogen production device 200. FIG. 5 is a flow diagram of control processing executed by the control device 201. FIG. 6 is a block diagram of a modified example of the hydrogen production device of the present invention. FIG. 7 is a cross-sectional view of a main portion of one embodiment of a solid carbon capture catalyst. FIG. 8 is a block diagram showing the main portion of the hydrogen production method of the present invention. FIG. 9 is a block diagram showing the basic configuration of a hydrogen production device that can be used for implementing the hydrogen production method of the present invention. FIG. 10 is a block diagram of an embodiment of the hydrogen production device that can be used for implementing the hydrogen production method of the present invention (heat supply from a methane combustion furnace to a dry reforming reaction). FIG. 11 is a block diagram of another embodiment of the hydrogen production device that can be used for implementing the hydrogen production method of the present invention (heat supply from a hydrogen combustion furnace to a dry reforming reaction). FIG. 12 is a block diagram of yet another embodiment of the hydrogen production device that can be used for implementing the hydrogen production method of the present invention (heat recovery from exhaust gas and heat supply to a dry reforming reaction). FIG. 13 is a block diagram of yet another embodiment of the hydrogen production device that can be used for implementing the hydrogen production method of the present invention (heat recovery from exhaust gas and heat control). FIG. 14 is a block diagram of yet another embodiment of the hydrogen production device that can be used for implementing the hydrogen production method of the present invention (form including a compressor). FIG. 1 is a block diagram of yet another embodiment of a hydrogen production apparatus that can be used to implement the hydrogen production method of the present invention (a configuration in which a plurality of solid carbon collectors are arranged in parallel). FIG. 2 is a block diagram of yet another embodiment of a hydrogen production apparatus that can be used to implement the hydrogen production method of the present invention (a configuration in which a plurality of solid carbon collectors are arranged in series). FIG. 3 is a graph showing gas composition by temperature in a solid carbon collector. FIG. 4 is a block diagram of yet another embodiment of a hydrogen production apparatus that can be used to implement the hydrogen production method of the present invention (temperature control of the DRM reaction and the solid carbon capture reaction). FIG. 5 is a photograph of the hydrogen production apparatus used in the demonstration experiment. FIG. 6 is a result of the demonstration test. FIG. 7 is a schematic explanatory diagram showing a simulation of the material balance and energy balance of the hydrogen production method of Example 2. FIG. 8 is a schematic explanatory diagram showing a simulation of the material balance and energy balance of the hydrogen production method of Example 3. FIG. 9 is a schematic explanatory diagram showing a simulation of the material balance and energy balance of the hydrogen production method of Example 4.FIG. 10 is a schematic explanatory diagram showing a simulation of the material balance and the energy balance of the hydrogen production method of Example 5.

[0012] The present invention will be described in detail below. The following description of the constituent elements may be based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment. In this specification, a numerical range expressed using "X to Y" means a range that includes the numerical values ​​represented by X and Y as the lower and upper limits, respectively. In the following description, parts having the same function and / or structure may be assigned the same reference numerals, and their description may be omitted.

[0013] [Hydrogen Production Method] The hydrogen production method of the present invention (hereinafter also referred to as "the production method") includes a step of performing a dry reforming reaction in the presence of a dry reforming catalyst to obtain a synthesis gas containing carbon monoxide and hydrogen from a feed gas containing methane and carbon dioxide (dry reforming step), a step of performing a solid carbon capture reaction in the presence of a solid carbon capture catalyst to generate solid carbon from the carbon monoxide in the synthesis gas, and to obtain solid carbon and a treated gas (carbon capture step), and a step of separating the treated gas into an exhaust gas and hydrogen to obtain hydrogen (hydrogen gas) (hydrogen separation step).

[0014] One of the features of the present invention is that in order to obtain the desired effect, the molar ratio of the carbon monoxide content to the carbon dioxide content in the synthesis gas (CO / CO ２ ) and the reaction temperature T １ (°C), the reaction temperature T of the solid carbon capture reaction ２ (°C) and are controlled so as to satisfy the following condition (1).

[0015] In the following, first, one embodiment of a hydrogen production apparatus that can be used to carry out the present production method will be described, and then the meaning of the above condition (1) and the CO / CO ratio in the synthesis gas will be described. ２ and reaction temperature T １ , T ２ The mechanism by which the effects of the present invention are achieved by controlling the relationship between the above and the above will be explained.

[0016] FIG. 1 is a block diagram of one embodiment of a hydrogen production device that can be used to implement the present production method.

[0017] The hydrogen production device 100 has a dry reforming reactor 103 (hereinafter also referred to as a "DRM reactor"), a solid carbon collector 106, and a hydrogen separator 107, which are connected in sequence via a flow path 115 for circulating gas.

[0018] The DRM reactor 103 is a dry reforming catalyst 101 (hereinafter also referred to as a "DRM catalyst") and a gas flowing through the DRM reactor 103. The temperature of the gas (reaction temperature T １ The solid carbon collector 106 includes a first temperature controller 102 for controlling the temperature (reaction temperature T ２ and a second temperature regulator 105 for controlling the temperature of the first temperature regulator 102.

[0019] The hydrogen production device 100 contains methane (CH ４ ) and carbon dioxide (CO ２ A raw material gas 110 containing CH 2 , CH 3 , CH 4 , CH 5 , CH 6 , CH 7 , CH 8 , CH 9 , CH 10 , CH 11 , CH 20 , CH 30 , CH 40 , CH 50 , CH 60 , CH 70 , CH 80 , CH 90 , CH 10 , CH 11 , CH 10 , CH 11 , CH 20 , CH 10 , CH 11 , CH 20 , CH 10 , CH 11 , CH 20 , CH 10 , CH 11 , CH 10 , CH 10 , CH 20 , CH 1 ... ４ +CO ２ → 2CO + 2H ２ The resulting synthesis gas 111 contains carbon monoxide (CO) and hydrogen generated by the DRM reaction. １ Depending on the temperature (°C), there may be residual methane that can be burned to carbon dioxide.

[0020] The dry reforming reactor 103 is configured to have a reaction temperature T １ There are no particular limitations on the type of device as long as it can bring the raw material gas 110 (raw material gas flow) into contact with the dry reforming catalyst 101. For example, the device may be configured to include a container through which the raw material gas 110 can flow, the dry reforming catalyst 101 fixed in the container, and a first temperature regulator 102 which is a heater.

[0021] The dry reforming catalyst 101 may be a composite including a porous support containing alumina and an active component supported on the porous support, such as nickel, cobalt, molybdenum, rhodium, ruthenium, aluminum, zirconium, magnesium, palladium, zinc, potassium, calcium, or oxides thereof.

[0022] In addition to the above, the dry reforming catalyst 101 may also be, for example, the catalysts described in Japanese Patent Application Laid-Open No. 2006-055820 and Japanese Patent Application Laid-Open No. 2019-37905.

[0023] Furthermore, from the viewpoint of obtaining a more excellent effect of the present invention, the dry reforming catalyst is "Ni#Y" described in Chemical. Science., 2019, volume 10, pp. 3701-3705. ２ O ３ " catalyst is preferred.

[0024] "Ni#Y ２ O ３ " is a fibrous mixture of metallic nickel and oxygen-deficient Yb, several tens of nanometers thick. ２ O ３ These intertwine to form a rooted structure.

[0025] "Ni#Y ２ O ３ " can be produced, for example, by the following method. First, metallic nickel and metallic yttrium are melted in an argon atmosphere to synthesize a Ni—Y alloy. This Ni—Y alloy powder (average particle size 50 to 60 μm) is mixed with CO, O ２ By heating with a gas flow consisting of Ni#Y and Ar, ２ O ３ " can be synthesized.

[0026] Next, synthesis gas 111 is introduced from the upstream side of the solid carbon trap 106. While flowing through the solid carbon trap 106, the synthesis gas 111 undergoes a solid carbon trap reaction to become treated gas 112 (solid carbon trap (Boudoor) reaction: 2CO → C + CO ２ ).

[0027] 11 is a cross-sectional view of a main part of one embodiment of a solid carbon capture catalyst 104. The solid carbon capture catalyst 104 has a tubular substrate 11 and a coating layer 12 formed on the inner wall surface of the substrate 11.

[0028] The substrate 11 of the solid carbon capture catalyst 104 is a tubular body, so that the synthesis gas 111 can easily flow through the solid carbon capture catalyst 104. In addition, there is an advantage that the fewer structures that obstruct the flow inside the tubular body, the less likely clogging due to precipitated solid carbon will occur.

[0029] The substrate 11 is not particularly limited as long as it can be coated with a metal-containing component, and may be a stainless steel pipe, an aluminum pipe, etc. When the substrate 11 is a tubular body having an inner wall surface with a circular cross section, its inner diameter is not particularly limited, and may be, for example, 10 to 300 mm or 10 to 1000 mm.

[0030] When the substrate 11 is a tubular body, its length is not particularly limited, but may be, for example, 20 to 5000 mm. The substrate 11 may be a tubular body that extends linearly or a twisted tubular body.

[0031] The coating layer 12 contains, as a main component, at least one metal-containing component selected from the group consisting of iron oxide, cobalt oxide, magnesium oxide, molybdenum oxide, nickel oxide, manganese oxide, metallic iron, metallic cobalt, metallic magnesium, metallic molybdenum, metallic nickel, and metallic manganese.

[0032] The coating layer 12 may contain iron oxide, and in particular, the iron oxide may be Fe ３ O ４ , Fe ２ O ３ , FeO, or a combination thereof. The content of these metal-containing components in the coating layer 12 is preferably 40 mass % or more, more preferably 50 mass % or more, even more preferably 60 mass % or more, particularly preferably 70 mass % or more, and preferably 100 mass % or less, when the total mass of the coating layer 12 is 100 mass %.

[0033] The coating layer 12 is made of aluminum oxide (Al ２ O ３ In this case, the proportion of metallic iron may be 40 to 50 mass % when the mass of the coating layer 12 is taken as 100 mass %.

[0034] The coating layer 12 is formed so as to cover the entire or part of the surface (inner wall surface) of the substrate 11. The thickness of the coating layer 12 is not particularly limited, but may be, for example, 5 to 2000 μm or 10 to 2000 μm.

[0035] From the viewpoint of efficient deposition of solid carbon, the coating layer 12 may be porous. The specific surface area of ​​the porous coating layer is 5 to 1000 m. ２ / g.

[0036] The coating layer 12 can be formed by a method including: applying a coating liquid containing at least one metal-containing component selected from the group consisting of iron oxide, cobalt oxide, magnesium oxide, molybdenum oxide, nickel oxide, manganese oxide, metallic iron, metallic cobalt, metallic magnesium, metallic molybdenum, metallic nickel, and metallic manganese, or a precursor thereof, and a solvent, to the surface (e.g., inner wall surface) of the substrate 11; and removing the solvent from the coating liquid applied to the surface of the substrate 11. The solvent for the coating liquid may be, for example, water, alcohol, acetone, or a combination thereof.

[0037] The solid carbon collector 106 is a solid carbon collector catalyst 104 and a reaction temperature T ２ Specifically, the reactor includes a reaction tube, a solid carbon capture catalyst 104 accommodated in the reaction tube, and the second temperature regulator 105 which is a heater arranged around the reaction tube, and a flow path for introducing a synthesis gas 111 is connected to the upstream (primary) side of the reaction tube, and a flow path for discharging a treated gas 112 is connected to the downstream (secondary) side of the reaction tube.

[0038] When the synthesis gas 111 is introduced into the solid carbon collector 106, solid carbon is deposited on the coating layer 12 of the solid carbon capture catalyst 104. The deposited solid carbon can be easily peeled off.

[0039] The treated gas 112 is introduced from the upstream side of the hydrogen separator 107 and separated into hydrogen 113 and exhaust gas 114 .

[0040] The hydrogen separator 107 has a function of separating the treated gas 112 into hydrogen 113 and exhaust gas 114, and may include a hydrogen separation membrane, a pressure swing adsorption mechanism, and the like.

[0041] The hydrogen separation membrane may be, for example, a thin palladium alloy membrane. Examples of the palladium alloy hydrogen separation membrane include palladium to which rare earth elements such as yttrium and gadolinium have been added, and palladium to which silver has been added. Also, thin membranes containing niobium, vanadium, titanium, tantalum, zirconium, or the like as the main component may be used instead of palladium.

[0042] Examples of such hydrogen separation membranes include those described in Japanese Patent Application Laid-Open Nos. 2000-159503, 2005-232533, and 2006-43677.

[0043] Furthermore, a hydrogen separation membrane that combines excellent hydrogen permeability and hydrogen embrittlement resistance may be obtained by adding at least one metal component selected from the group consisting of chromium, iron, nickel, and cobalt to vanadium, or by adding at least one metal component selected from the group consisting of aluminum, scandium, titanium, yttrium, zirconium, niobium, molybdenum, tantalum, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and ruthenium to vanadium. Such a hydrogen separation membrane is described, for example, in JP 2008-55295 A.

[0044] The hydrogen separator 107, which includes a hydrogen separation membrane, typically has a hydrogen separation membrane, a flow path for supplying treated gas 112 from the upstream (primary) side of the hydrogen separation membrane to the hydrogen separation membrane, a flow path for discharging hydrogen 113 that has permeated the hydrogen separation membrane to the downstream (secondary) side, and a flow path for recovering exhaust gas 114 that has come into contact with the hydrogen separation membrane but has not permeated the hydrogen separation membrane.

[0045] The hydrogen separator 107 including such a hydrogen separation membrane can be, for example, that described in Japanese Patent Application Laid-Open No. 2019-5684.

[0046] In addition to the above, the hydrogen separator 107 may also be one that uses a pressure swing adsorption (PSA) method. A PSA hydrogen separator typically includes an adsorption tower filled with an adsorbent, a pump, and a flow path connecting these. The adsorbent may be one that adsorbs carbon dioxide, carbon monoxide, moisture, and the like in the treated gas 112. Activated carbon, zeolite, alumina, and the like may be used as the adsorbent.

[0047] In a PSA hydrogen separator, one cycle of adsorption, desorption, and cleaning is performed repeatedly for one adsorption tower. Adsorption is a process in which carbon dioxide, carbon monoxide, etc. in the treated gas 112 are adsorbed onto an adsorbent, and hydrogen is extracted. Desorption is a process in which the pressure inside the adsorption tower is reduced, and carbon dioxide, carbon monoxide, etc. are desorbed from the adsorbent, and extracted as exhaust gas 114. Cleaning is a process in which the adsorption tower is cleaned with hydrogen.

[0048] In a PSA hydrogen separator, a flow path for introducing treated gas 112 is connected to the primary side, and a pipeline for discharging hydrogen 113 and a flow path for discharging exhaust gas 114 are connected to the secondary side.

[0049] The exhaust gas 114 discharged from the hydrogen separator 107 contains carbon dioxide, carbon monoxide, unseparated hydrogen, and the like.

[0050] Next, in the production of hydrogen using this hydrogen production device 100, CO as part of the raw material gas 110 ２and the amount of CO in the exhaust gas 114 ２ The balance of the derived amounts will be explained. ２ The derived amount of CO may be contained in the exhaust gas 114 and may be CO ２ The calculation also takes into account the effect of CO, which may cause

[0051] First, the DRM reactor 103 was charged with 100 mmol / min of CH ４ and CO ２ A case will be considered in which a raw material gas 110 (135 L / h) containing the above-mentioned mixed gas is introduced and flows from the upstream to the downstream of the flow path 115 of the hydrogen production device 100. Here, the DRM reactor 103 is maintained at 600° C., that is, the reaction temperature T １ is set to 600°C.

[0052] Assuming that thermodynamic equilibrium exists between the DRM catalyst 101 and the gas flow in the DRM reactor 103, the composition of the synthesis gas 111 can be estimated by heat balance calculation.

[0053] As an example, the composition of the raw material gas 110 flowing into the hydrogen production device 100 is set to a volume ratio of CH ４ :CO ２ = 1:9 (14:121 (L / hr)), the composition of the synthesis gas 111 is CH ４ : H ２ :CO ２ :CO:H ２ CO / CO = 1:13:96:38:12 (L / hour). ２ becomes 0.396.

[0054] For this synthesis gas, solid carbon capture was performed at T ２ = 600 ° C., and CO and CH contained in the exhaust gas after hydrogen separation ４ is burned, and CO ２ When the CO contained in the gas released to the outside of the device is ２ The amount of CO introduced into the hydrogen production device is 121 (L / h). ２ and the amount of CO emitted ２ The amounts are mathematically equal.

[0055] Reaction temperature T １ and T２ and CO / CO in the synthesis gas. ２ If the CO introduced into the hydrogen production device is 0.953, ２ The CO / CO ratio is 101 L / hour, while the CO / CO ratio is 105 L / hour. ２ If the inflow rate is 90 L / hour, the discharge rate is 103 L / hour. ２ If the ratio is 1.53, the discharge amount is 102 L / hour for an inflow amount of 81 L / hour.

[0056] On the other hand, the reaction temperature T １ at 600°C, and reaction temperature T ２ is 451°C, the CO / CO ２ CO when set to 0.396 ２ The amount of discharged water is 116 L / hour. In this case, the amount of discharged water is smaller than the amount of inflow of 121 L / hour.

[0057] A hypothetical mechanism for obtaining the above thermodynamic response will be explained. Figure 2 shows the Boudouard reaction (2CO → CO ２ 2. In FIG. 2, the open (open) circular symbols and the closed (black) circular symbols represent the reaction temperature T ２ CO in the treated gas 112 (outgoing gas, labeled "Outgas" in the figure) ２ , and the mole fraction of CO (vertical axis: left). The open square symbols indicate the reaction temperature T ２ CO / CO in the treated gas 112 (°C) ２ (vertical axis: right).

[0058] According to Fig. 2, the light-off temperature (activation temperature) can be theoretically estimated to be 450°C. In this specification, the light-off temperature (activation temperature) is calculated based on the total amount of CO and CO ２ The reaction temperature T ２This means the lowest temperature at which the amount of CO contained in the treated gas 112 changes from zero to a significant value when the temperature is gradually increased from 350°C.

[0059] Also, according to FIG. 2, the reaction temperature T ２ According to the change in the equilibrium, the equation is: 2CO → CO ２ +C from right to left, and CO and CO in the treated gas 112 ２ The mole fraction of CO ２ It can be seen that the ratio of CO changes from about 0.5:0.0 to about 0.0:1.0.

[0060] That is, the reaction temperature T ２ As the temperature is gradually increased, the equilibrium of the Boudouard reaction shifts from right to left, and the amount of CO contained in the treated gas 112 also increases. ２ By reducing this CO2 emission, the final CO2 ２ can reduce emissions.

[0061] CO outside the hydrogen production device ２ The discharge amount of CH contained in the treated gas 112 is ４ It is also affected by the amount of CH ４ If it contains CH ４ does not contribute to the solid carbon capture reaction and is emitted into the treated gas 112. When this is burned, CO ２ The CH in the synthesis gas 111 ４ The amount of CH that was not used in the DRM reaction is, so to speak, the remaining CH ４ This is also possible, and adjustments are necessary.

[0062] The present inventors have determined that the reaction temperature T ２ , and CO / CO in the synthesis gas 111 ２ By controlling within a predetermined range, CO ２ The conditions under which the derived amount is equal to or less than the introduced amount were searched for. As a result, it was noticed that the "range" formed a continuous region, and the reaction temperature T １ , reaction temperature T２ , and CO / CO in the synthesis gas 111 ２ The relationship between was further examined.

[0063] Specifically, the reaction temperature T １ , T ２ The same calculations as above were performed while changing the reaction temperature T １ , reaction temperature T ２ , and CO / CO in the synthesis gas 111 ２ FIG.

[0064] In FIG. 3, the horizontal axis indicates "CO / CO ２ "Ratio in DRM Outgas" is the CO / CO ratio in the synthesis gas 111. ２ The vertical axis "CO Disprop. Temperature (°C)" represents the reaction temperature T ２ Each plot represents the "DRM Temperature", i.e., the reaction temperature T １ In CO ２ This is the point at which the amount derived is theoretically equal to the amount introduced.

[0065] For example, the reaction temperature T １ When the temperature is 600°C, in the inner area of ​​each plot (towards the origin), ２ The amount of outflow is smaller, typically less than the amount of inflow. １ As the CO ２ It can be seen that the area defined by each plot where the derived amount is equal to the introduced amount becomes larger.

[0066] From FIG. 3, the present invention can be realized by using the reaction temperature T １ In CO ２ We hypothesized that the set of points where the amount of output is equal to the amount of input follows a sigmoid curve. Furthermore, this sigmoid curve follows the reaction temperature T １ As the value of σ increases, the slope (absolute value) decreases and the inflection point moves in the positive direction of the horizontal axis.

[0067] Specifically, the reaction temperature T １CO ２ The "COCO" software calculates the region where the derived amount is equal to the introduced amount, and the region where the following condition (1) is met:

[0068] Inflection refers to the inflection point (horizontal axis) of the sigmoid curve, and gradient refers to the inclination of the slope.

[0069]

[0070] Table 1 shows the reaction temperature T １ The values ​​of 600° C., 700° C., and 900° C. were obtained by fitting.

[0071] From the results in Table 1 and Figure 3, the Inflection and Gradient are １ 4 shows a diagram illustrating this relationship.

[0072] In FIG. 4, the horizontal axis represents the reaction temperature T １ The triangle plots represent the inflection, and the square plots represent the gradient. The relational equations obtained from fitting each plot were as follows: １ (°C) is preferably 600°C or higher.

[0073]

[0074] That is, each reaction temperature T １ In CO ２ It has been found that the region where the amount of derived is significantly reduced, typically the region where the amount of introduced is smaller, is the region that satisfies the following condition (1).

[0075]

[0076] From the above equations (2) and (3), the reaction temperature T １The inflection and gradient when σ is 800°C were calculated (the results are shown in Table 1), and the sigmoid curve on the right side of the inequality sign on the right side of (1) obtained as a result is the curve represented by "sim800°C" in Figure 3. This curve matches the plots obtained by separate calculations, and it was found that the above condition settings were correct.

[0077] From the above, if the manufacturing method satisfies condition (1), the amount of CO emitted outside the device ２ The amount of CO is significantly reduced, typically ２ It was found that the amount introduced and the amount derived were equal or less than each other.

[0078] It is easy for a person skilled in the art to operate the hydrogen production device 100 under such conditions because the temperature of the dry reforming reaction (reaction temperature T １ ) is determined, the CO / CO ratio in the DRM outgas (i.e., syngas 111) is ２ is the CH in the source gas 110 ４ / CO ２ This is because it can be easily adjusted by adjusting

[0079] FIG. 5 shows the CH ４ / CO ２ and CO / CO in the synthesis gas 111 ２ The relationship between the reaction temperature T １ The horizontal axis of FIG. ４ / CO ２ in DRM InGas,” that is, CH in the source gas 110 ４ / CO ２ The vertical axis represents "CO / CO ２ in DRM OutGas”, i.e., CO / CO in the synthesis gas 111 ２ represents.

[0080] As shown in FIG. 5, the reaction temperature T １ When determining the CO / CO ratio in the synthesis gas, ２ To adjust to a desired value, the CH ４ / CO ２The value can be easily calculated.

[0081] Regarding condition (1), CO / CO ２ is greater than 0 and equal to or less than 124, and the lower limit is preferably 0.20 or more. ２ When the CO / CO ratio is equal to or greater than the lower limit, the effects of the present invention are more excellent. The upper limit is preferably 0.50 or less. ２ When it is equal to or less than the upper limit, the effect of the present invention is more excellent.

[0082] 6 is a flow diagram of the present hydrogen production method. First, in step S10, the reaction temperature T １ The dry reforming reaction is carried out at a reaction temperature T １ The reaction can be carried out by flowing the raw material gas 110 at a reaction temperature T １ Although there are no particular limitations on the reaction temperature, it is preferably equal to or higher than the activation temperature of the dry reforming catalyst. In one specific embodiment, it is preferably 600°C or higher, and more preferably 1100°C or lower, and more preferably 900°C or lower. １ can be adjusted by controlling the first temperature regulator 102 of the dry reforming reactor 103.

[0083] The method for adjusting the mixture ratio of methane and carbon dioxide in the raw material gas 110 is not particularly limited, but an example thereof is a method in which a raw material gas regulator having a gas mixer and a mass flow controller adjusts the mixture ratio of methane and carbon dioxide supplied via flow paths.

[0084] In addition, the reaction temperature T １ (°C), and CH in the source gas 110 ４ / CO ２ Once this is determined, the CO / CO ratio in the synthesis gas 111 can be calculated. ２ can be calculated.

[0085] Next, in step S11, a solid carbon capture reaction is carried out so as to satisfy the above-mentioned condition (1) (solid carbon capture reaction step). The solid carbon capture reaction is carried out by heating the solid carbon collector 106 at a reaction temperature T２ This can be done by passing the synthesis gas 111 through the

[0086] In order to carry out the solid carbon capture reaction so as to satisfy the condition (1), the CH ４ / CO ２ , and reaction temperature T １ The composition of the synthesis gas 111 (CO / CO ２ ) based on the corresponding reaction temperature T ２ (° C.) and control the second temperature regulator 105 accordingly.

[0087] Next, in step S12, the treated gas 112 produced by the solid carbon capture reaction is separated into exhaust gas 114 and hydrogen 113 to obtain the hydrogen 113 (hydrogen separation step). The treated gas 112 is introduced into the hydrogen separator 107, which is operated under known conditions, whereby the hydrogen 113 can be separated.

[0088] Next, in step S13, heat is recovered from the exhaust gas 114 (heat recovery step). Since the exhaust gas 114 contains carbon monoxide, hydrogen, etc., this can be done, for example, by burning these. The recovered heat is preferably used for the dry reforming reaction and / or the solid carbon capture reaction. Note that the hydrogen production method of the present invention does not necessarily have to include this step.

[0089] According to this production method, as described above, the CO / CO ratio in the synthesis gas 111 ２ and reaction temperature T ２ By adjusting the temperature and pressure within an appropriate range, when producing hydrogen from a raw material gas containing methane and carbon dioxide, CO ２ can significantly reduce emissions.

[0090] 7 is a block diagram of a hydrogen production apparatus according to a first embodiment of the present invention. The hydrogen production apparatus 200 includes a DRM reactor 103, a solid carbon collector 106, a hydrogen separator 107, a heat recovery unit 204, and a raw material gas regulator 205, which are connected via a flow path 115 through which gas can flow.

[0091] Of these, the raw material gas regulator 205, the DRM reactor 103, the solid carbon collector 106, and the hydrogen separator 107 are connected in sequence (in series), and the primary side of the heat recovery unit 204 is connected to a flow path 115 for the exhaust gas 114 that branches off from the hydrogen separator 107. The flow path 115 connected to the secondary side of the heat recovery unit 204 joins the raw material gas regulator 205 and the DRM reactor 103.

[0092] In the hydrogen production device 200, the various parts (components) are connected by the flow path 115 as described above, but the connection form (connection path) of the various parts in the hydrogen production device of the present invention is not limited to the above.

[0093] For example, the hydrogen separator 107 may be disposed between the DRM reactor 103 and the solid carbon collector 106. Also, a plurality of one or more types of components may be disposed, in which case the flow path 115 may branch and the same type of components may be arranged in parallel, or the same type of components may be arranged consecutively.

[0094] In addition to the above, the hydrogen production apparatus 200 may further include one or more valves, steam removers, pressure regulators (pressure reducing valves, compressors), heat exchangers, etc., within the scope of the effects of the present invention. The DRM reactor 103, solid carbon collector 106, and hydrogen separator 107 included in the hydrogen production apparatus 200 are the same as those already described, and therefore further description will be omitted.

[0095] The heat recovery device 204 has a function of recovering heat from methane, carbon monoxide, hydrogen, etc. that may be contained in the exhaust gas 114 generated when the hydrogen 113 is separated from the treated gas 112 by the hydrogen separator 107. Specifically, the heat recovery device 204 may be a burner that combusts the exhaust gas 114, a fuel cell that uses the exhaust gas 114 as fuel, or the like.

[0096] The heat recovered by the heat recovery device 204 is preferably used to control the temperature of the DRM reactor 103 and / or the solid carbon collector 106 (heat transfer is indicated by the symbol "Q" in the drawing). The circulating gas 120 discharged from the heat recovery device 204 contains carbon dioxide, which is mixed with the raw material gas 110 for use.

[0097] As will be described later, the hydrogen production device 200 can reduce CO generated during hydrogen production. ２ In one embodiment, the amount of CO contained in the circulation gas 120 is significantly reduced. ２ is the CO in the raw material gas 110 ２ Since the amount is less than the required amount, ２ While supplying CO ２ It is also possible to operate the system in a circulating manner without discharging the wastewater.

[0098] The raw material gas regulator 205 has a function of mixing the methane 121 and the carbon dioxide 122 to adjust the composition of the raw material gas 110. The raw material gas regulator 205 may be configured by a gas mixer that mixes the methane 121 and the carbon dioxide 122 supplied through a flow path at an arbitrary ratio, a mass flow controller, and the like.

[0099] The hydrogen production device 200 has a control device 201. The control device 201 is a computer including a processor 202 and a memory 203. The control device 201 controls the DRM reactor 103, the solid carbon collector 106, and the raw material gas regulator 205. In addition to the above, the hydrogen separator 107 and the heat recovery device 204 may also be controlled.

[0100] The control device 201 has a plurality of sensors for detecting the operating state of the hydrogen production device 200. Detection signals from the plurality of sensors are input to the control device 201. The control device 201 controls the reaction temperature T １ a temperature sensor (TEMP1) 130 for detecting the reaction temperature T of the solid carbon capture reaction in the solid carbon collector 106; ２and a flow rate sensor (FLOW) 132 that detects the mixture ratio of methane 121 and carbon dioxide 122 in the raw material gas regulator 205.

[0101] TEMP1 and TEMP2 may directly detect the temperatures of the gases in the DRM reactor 103 and the solid carbon collector 106, or may estimate each temperature from physical quantities such as the outputs of the first temperature controller 102 and the second temperature controller 105 and the operating time.

[0102] The control device 201 controls, for example, the reaction temperature T １ The detection signal of the temperature sensor (TEMP1) 130 is acquired, and the output of the first temperature regulator 102 of the DRM reactor 103 is adjusted based on the acquired information.

[0103] The control device 201 includes a processor 202, which is a hardware device, and the processor 202 may be a processor core that executes a program stored in a memory. Such a processor core may be a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit).

[0104] The processor 202 may be a hardware logic circuit including a programmed logic unit. The digital circuit may be a logic circuit array, such as an ASIC (Application-Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), an SoC (Systemona Chip), a PGA (Programmable Gate Array), and a CPLD (Complex Programmable Logic Device).

[0105] The control device 201 includes a memory 203. The memory is a non-transient, tangible storage medium that non-temporarily stores a program and / or data that can be read by the processor. The storage medium is provided by a semiconductor memory, a magnetic disk, an optical disk, or the like. The program may be distributed independently or as a storage medium on which the program is stored. The processor 202 may also be a combination of a processor core and a hardware logic circuit.

[0106] 8 is a flow diagram of hydrogen production by the hydrogen production device 200. In step S20, the control device 201 controls the first temperature regulator 102 and the raw material gas regulator 205 to adjust the reaction temperature T １ The DRM reaction is carried out at (°C).

[0107] Specifically, the state at the time of DRM reaction is CH ４ / CO ２ is acquired by the flow rate sensor (FLOW) 132, and the reaction temperature T １ (°C) is acquired by the temperature sensor (TEMP1) 130. ４ / CO ２ is adjusted by the raw material gas regulator 205, and the reaction temperature T １ is adjusted by the first temperature adjuster 102.

[0108] In addition, when the raw material gas 110 is prepared by merging the circulating gas 120, the CO ２ Based on the content of ４ / CO ２ The CO in the circulation gas 120 may be adjusted. ２ The content of can be calculated from the composition of the raw material gas 110 used in its production, but a sensor for measuring the composition of the circulating gas 120 may be provided midway through the flow path 115, and the control device 201 may acquire the measured value and use it to control the raw material gas regulator 205.

[0109] In this step S20, a synthesis gas 111 containing hydrogen and carbon monoxide is obtained from a raw material gas 110 containing methane and carbon dioxide.

[0110] Next, in step S21, the control device 201 controls the second temperature regulator 105 to perform a solid carbon capture reaction so as to satisfy the condition (1). ４ / CO ２ CO / CO of syngas 111 calculated from ２ , the reaction temperature T acquired by the temperature sensor (TEMP1) 130 １ (°C), and the reaction temperature T obtained by the temperature sensor (TEMP2) 131 ２ Based on the temperature (°C), the control device 201 determines whether the reaction conditions of the solid carbon capture reaction satisfy condition (1), and controls the outputs of the raw material gas regulator 205, the first temperature regulator 102, and the second temperature regulator 105 so as to satisfy this condition, thereby adjusting the CO / CO ２ , reaction temperature T １ , and reaction temperature T ２ Adjust.

[0111] In step S21, solid carbon is separated from the synthesis gas 111 containing carbon monoxide, and a treated gas 112 containing carbon dioxide, etc. is obtained. Note that the treated gas 112 may contain methane, carbon monoxide, water vapor, hydrogen, etc. in addition to carbon dioxide.

[0112] Next, in step S22, hydrogen 113 is separated and obtained from the treated gas 112 by the hydrogen separator 107, and an exhaust gas 114 is also obtained.

[0113] Next, in step S23, the heat recovery unit 204 recovers heat from the exhaust gas 114, generating a circulation gas 120. The heat Q generated in step S23 is supplied to the DRM reactor 103 and / or the solid carbon collector 106, and is used to adjust the reaction temperatures.

[0114] The circulating gas 120 generated in step S23 is passed through a flow path to join the raw material gas regulator 205 and the DRM reactor 103, and is used as part of the raw material gas 110.

[0115] 9 is a flow chart of the control process executed by the control device 201 in the above-mentioned step S21. The control device 201 controls the reaction conditions of the DRM reaction and the solid carbon capture reaction by executing the above-mentioned control process. ２ emissions will be significantly reduced.

[0116] In step S30, the control device 201 acquires information about the operating state of the hydrogen production device 200. Specifically, the temperature sensor (TEMP1) 130 detects the temperature of the gas inside the DRM reactor 103 (reaction temperature T １ In addition, the flow rate sensor (FLOW) 132 acquires the flow rates (mixing ratio) of methane and carbon dioxide in the raw material gas regulator 205 .

[0117] In step S31, the control device 201 controls the CH ４ / CO ２ Ratio and reaction temperature T １ (°C), the CO / CO in the synthesis gas ２ Calculate CO / CO ２ is calculated based on the CH ４ / CO ２ , and reaction temperature T １ This is done by heat balance calculation based on the above. Software programs such as "COCO" can be used for this calculation.

[0118] Next, in step S32, the control device 201 detects the temperature of the gas in the solid carbon collector 106 (reaction temperature T ２ ) to obtain the

[0119] Next, in step S33, the control device 201 determines the CO / CO ratio in the synthesis gas 111 introduced into the solid carbon collector 106. ２ and the reaction temperature T １ (°C) and reaction temperature T ２ (° C.) satisfies condition (1).

[0120] Specifically, in step S33, the determination is made through the following steps: １ Based on the calculated CO / CO ratio, the Inflection and Gradient are calculated from Equations (2) and (3). Next, the sigmoid curve on the right side of the inequality sign on the right side of Condition (1) is obtained from the calculated Inflection and Gradient. ２ and the obtained reaction temperature T ２ Based on these, it is determined whether the value is within the range of the sigmoid curve.

[0121] If the result of the above determination is that the condition (1) is not satisfied (step S33: NO), in steps S34 to S36, the reaction temperature T １ (Step S34), and based on the detection signal of the flow rate sensor (FLOW) 132, the raw material gas regulator 205 controls the flow rates (mixing ratio) of methane and carbon dioxide in the raw material gas 110 (Step S35), and based on the detection signal of the temperature sensor (TEMP2) 131, the second temperature regulator 105 controls the reaction temperature T ２ (step S36).

[0122] Thereafter, steps S30 to S32 are repeated, and the determination in step S33 is made. Steps S34 to S36 and steps S30 to S33 are repeated until condition (1) is satisfied.

[0123] On the other hand, if the result of the judgment in step S33 is that condition (1) is satisfied (step S33: YES), the control processing by the control device 201 ends, and the process returns to FIG. 8, and the subsequent steps (step S22 and step S23) are executed.

[0124] The hydrogen production device 200 has a control device 201, and the control device 201 controls the CO / CO ratio in the synthesis gas 111. ２ , and reaction temperature T ２Since each part is controlled to satisfy condition (1), the amount of carbon dioxide emitted to the outside of the device when hydrogen is produced from the raw material gas is significantly reduced. In addition, since the hydrogen production device 200 has a heat recovery device 204, heat can be recovered from the hydrogen and carbon monoxide contained in the exhaust gas 114 and used for the DRM reaction and / or the solid carbon capture reaction, which also reduces the amount of carbon dioxide emitted due to heating, etc. (or the generation of electricity for that purpose).

[0125] Furthermore, the hydrogen production device 200 has a flow path that merges the circulating gas 120 with the raw material gas 110. In one embodiment, the carbon dioxide content in the circulating gas 120 is less than the (required) carbon dioxide content in the raw material gas, so that hydrogen production can be performed without discharging carbon dioxide used in the process outside the device, in other words, while constantly supplying carbon dioxide from outside the device.

[0126] [Hydrogen production apparatus (modified example)] Fig. 10 is a block diagram of a modified example of the hydrogen production apparatus of the present invention. The hydrogen production apparatus 200 already described has a DRM reactor 103 that performs the DRM reaction and a solid carbon collector 106 that performs the solid carbon capture reaction, but the hydrogen production apparatus 300 in Fig. 10 has a reactor 301 that serves as both the DRM reactor and the solid carbon collector instead.

[0127] A DRM catalyst 101 and a solid carbon capture catalyst 104 are disposed inside the reactor 301, and a raw material gas 110 introduced from the primary side first comes into contact with the DRM catalyst 101 to generate a synthesis gas 111. The synthesis gas 111 then comes into contact with the solid carbon capture catalyst 104 to generate a treated gas 112. The above reactions occur sequentially inside the reactor 301.

[0128] The temperature inside the reactor 301 is adjusted by a third temperature regulator 302 controlled by the control device 201, and the reaction temperature T １ , and reaction temperature T ２ are acquired by a temperature sensor (TEMP1) 130 and a temperature sensor (TEMP2) 131.

[0129] A specific example of the reactor 301 is a reactor having one reaction tube, a DRM catalyst 101 and a solid carbon capture catalyst 104 packed in this order in the reaction tube, and a heater for adjusting the temperature of the reaction tube.

[0130] The reactor 301 of the hydrogen production device 300 has a third temperature regulator 302 that regulates the temperature of the entire reactor. １ ) and a first temperature controller 102 that independently controls the temperature of the solid carbon capture reaction (reaction temperature T ２ ) and a second temperature regulator 105 that independently controls the first temperature regulator 102, and these may be controlled by the control device 201.

[0131] The hydrogen production device 300 has a reactor 301 that serves both as a DRM reactor and a solid carbon collector, and is further configured so that the reaction temperature is controlled by a third temperature regulator 302, which has the advantage of being simpler in structure and easier to control. １ , and reaction temperature T ２ When the temperature is controlled to 600 to 620°C, the above tendency is more pronounced.

[0132] [Main Parts of Hydrogen Production Method and Apparatus] FIG. 12 is a block diagram of the main parts of a hydrogen production apparatus that can be used to implement the hydrogen production method of the present invention.

[0133] The hydrogen production device 100 has a dry reforming reactor 103 (hereinafter also referred to as a "DRM reactor"), a solid carbon collector 106, and a hydrogen separator 107, which are connected in sequence via a flow path 115 for circulating gas.

[0134] The hydrogen production device 100 contains methane (CH ４ ) and carbon dioxide (CO ２ A raw material gas 110 containing CH 2 , CH 3 , CH 4 , CH 5 , CH 6 , CH 7 , CH 8 , CH 9 , CH 10 , CH 11 , CH 20 , CH 30 , CH 40 , CH 50 , CH 60 , CH 70 , CH 80 , CH 90 , CH 10 , CH 11 , CH 10 , CH 11 , CH 20 , CH 10 , CH 11 , CH 20 , CH 10 , CH 11 , CH 20 , CH 10 , CH 11 , CH 10 , CH 10 , CH 20 , CH 1 ... ４ +CO ２ → 2CO + 2H ２The resulting synthesis gas 111 contains carbon monoxide (CO) and hydrogen generated by the DRM reaction. １ Depending on the temperature (°C), there may be residual methane that can be burned to carbon dioxide.

[0135] [Dry Reforming Reactor] The DRM reactor 103 is not particularly limited as long as it can bring the raw material gas 110 (raw material gas flow) into contact with the dry reforming catalyst 101. For example, as shown in FIG. 12 , the DRM reactor 103 may include a container through which the raw material gas 110 can flow, a dry reforming catalyst 101 (hereinafter also referred to as the “DRM catalyst”) fixed in the container, and a temperature (reaction temperature T １ and a first temperature regulator 102 for controlling the temperature of the heating element 101 .

[0136] The dry reforming catalyst 101 may be a composite including a porous support containing alumina and an active component supported on the porous support, such as nickel, cobalt, molybdenum, rhodium, ruthenium, aluminum, zirconium, magnesium, palladium, zinc, potassium, calcium, or oxides thereof.

[0137] In addition to the above, the dry reforming catalyst 101 may also be, for example, the catalysts described in Japanese Patent Application Laid-Open No. 2006-055820 and Japanese Patent Application Laid-Open No. 2019-37905.

[0138] Furthermore, from the viewpoint of obtaining a more excellent effect of the present invention, the dry reforming catalyst is "Ni#Y" described in Chemical. Science., 2019, volume 10, pp. 3701-3705. ２ O ３ " catalyst is preferred.

[0139] "Ni#Y ２ O ３ " is a fibrous mixture of metallic nickel and oxygen-deficient Yb, several tens of nanometers thick. ２ O ３ These intertwine to form a rooted structure.

[0140] "Ni#Y ２ O３ " can be produced, for example, by the following method. First, metallic nickel and metallic yttrium are melted in an argon atmosphere to synthesize a Ni—Y alloy. This Ni—Y alloy powder (average particle size 50 to 60 μm) is mixed with CO, O ２ By heating with a gas flow consisting of Ni#Y and Ar, ２ O ３ " can be synthesized.

[0141] Next, synthesis gas 111 is introduced from the upstream side of the solid carbon trap 106. While flowing through the solid carbon trap 106, the synthesis gas 111 undergoes a solid carbon trap reaction to become treated gas 112 (solid carbon trap (Boudoor) reaction: 2CO → C + CO ２ ).

[0142] [Solid Carbon Collector] The solid carbon collector 106 is not particularly limited as long as it can bring the synthesis gas 111 from the DRM reactor 103 into contact with the solid carbon capture catalyst 104. ２ Specifically, the reactor includes a reaction tube, a solid carbon capture catalyst 104 accommodated in the reaction tube, and the second temperature regulator 105 which is a heater arranged around the reaction tube, and a first flow path 115a for introducing the synthesis gas 111 from the DRM reactor 103 is connected to the upstream (primary) side of the reaction tube, and a second flow path 115b for discharging the treated gas 112 is connected to the downstream (secondary) side of the reaction tube.

[0143] As shown in FIG. 11, the solid carbon capture catalyst 104 can have a configuration including a tubular substrate 11 and a coating layer 12 formed on the inner wall surface of the substrate 11 .

[0144] When the synthesis gas 111 is introduced into the solid carbon collector 106, solid carbon is deposited on the coating layer 12 of the solid carbon capture catalyst 104. The deposited solid carbon can be easily peeled off.

[0145] The substrate 11 of the solid carbon capture catalyst 104 is a tubular body, so that the synthesis gas 111 can easily flow through the solid carbon capture catalyst 104. In addition, there is an advantage that the fewer structures that obstruct the flow inside the tubular body, the less likely clogging due to precipitated solid carbon will occur.

[0146] The substrate 11 is not particularly limited as long as it can be coated with a metal-containing component, and may be a stainless steel pipe, an aluminum pipe, etc. When the substrate 11 is a tubular body having an inner wall surface with a circular cross section, its inner diameter is not particularly limited, and may be, for example, 10 to 300 mm or 10 to 1000 mm.

[0147] When the substrate 11 is a tubular body, its length is not particularly limited, but may be, for example, 20 to 5000 mm. The substrate 11 may be a tubular body that extends linearly or a twisted tubular body.

[0148] The coating layer 12 contains, as a main component, at least one metal-containing component selected from the group consisting of iron oxide, cobalt oxide, magnesium oxide, molybdenum oxide, nickel oxide, manganese oxide, metallic iron, metallic cobalt, metallic magnesium, metallic molybdenum, metallic nickel, and metallic manganese.

[0149] The coating layer 12 may contain iron oxide, and in particular, the iron oxide may be Fe ３ O ４ , Fe ２ O ３ , FeO, or a combination thereof. The content of these metal-containing components in the coating layer 12 is preferably 40 mass % or more, more preferably 50 mass % or more, even more preferably 60 mass % or more, particularly preferably 70 mass % or more, and preferably 100 mass % or less, when the total mass of the coating layer 12 is 100 mass %.

[0150] The coating layer 12 is made of aluminum oxide (Al ２ O ３In this case, the proportion of metallic iron may be 40 to 50 mass % when the mass of the coating layer 12 is taken as 100 mass %.

[0151] The coating layer 12 is formed so as to cover the entire or part of the surface (inner wall surface) of the substrate 11. The thickness of the coating layer 12 is not particularly limited, but may be, for example, 5 to 2000 μm or 10 to 2000 μm.

[0152] From the viewpoint of efficient deposition of solid carbon, the coating layer 12 may be porous. The specific surface area of ​​the porous coating layer is 5 to 1000 m. ２ / g.

[0153] The coating layer 12 can be formed by a method including: applying a coating liquid containing at least one metal-containing component selected from the group consisting of iron oxide, cobalt oxide, magnesium oxide, molybdenum oxide, nickel oxide, manganese oxide, metallic iron, metallic cobalt, metallic magnesium, metallic molybdenum, metallic nickel, and metallic manganese, or a precursor thereof, and a solvent, to the surface (e.g., inner wall surface) of the substrate 11; and removing the solvent from the coating liquid applied to the surface of the substrate 11. The solvent for the coating liquid may be, for example, water, alcohol, acetone, or a combination thereof.

[0154] [Hydrogen Separator] The treated gas 112 from the solid carbon collector 106 is introduced into the hydrogen separator 107 from the upstream side via the second flow path 115 b , and is separated into hydrogen 113 and exhaust gas 114 .

[0155] The exhaust gas 114 discharged from the hydrogen separator 107 contains carbon dioxide, carbon monoxide, and a small amount of unseparated hydrogen.

[0156] The hydrogen separator 107 is not particularly limited as long as it has the function of separating the treated gas 112 from the solid carbon collector 106 into hydrogen 113 and exhaust gas 114 while circulating the gas. It may include, but is not limited to, a hydrogen separation membrane and a pressure fluctuation adsorption mechanism.

[0157] The hydrogen separation membrane may be, for example, a thin palladium alloy membrane. Examples of the palladium alloy hydrogen separation membrane include palladium to which rare earth elements such as yttrium and gadolinium have been added, and palladium to which silver has been added. Also, thin membranes containing niobium, vanadium, titanium, tantalum, zirconium, or the like as the main component may be used instead of palladium.

[0158] Examples of such hydrogen separation membranes include those described in Japanese Patent Application Laid-Open Nos. 2000-159503, 2005-232533, and 2006-43677.

[0159] Furthermore, a hydrogen separation membrane that combines excellent hydrogen permeability and hydrogen embrittlement resistance may be obtained by adding at least one metal component selected from the group consisting of chromium, iron, nickel, and cobalt to vanadium, or by adding at least one metal component selected from the group consisting of aluminum, scandium, titanium, yttrium, zirconium, niobium, molybdenum, tantalum, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and ruthenium to vanadium. Such a hydrogen separation membrane is described, for example, in JP 2008-55295 A.

[0160] The hydrogen separator 107, which includes a hydrogen separation membrane, typically has a hydrogen separation membrane, a flow path for supplying treated gas 112 from the upstream (primary) side of the hydrogen separation membrane to the hydrogen separation membrane, a flow path for discharging hydrogen 113 that has permeated the hydrogen separation membrane to the downstream (secondary) side, and a flow path for recovering exhaust gas 114 that has come into contact with the hydrogen separation membrane but has not permeated the hydrogen separation membrane.

[0161] The hydrogen separator 107 including such a hydrogen separation membrane can be, for example, that described in Japanese Patent Application Laid-Open No. 2019-5684.

[0162] In addition to the above, the hydrogen separator 107 may also be one that uses a pressure swing adsorption (PSA) method. A PSA hydrogen separator typically includes an adsorption tower filled with an adsorbent, a pump, and a flow path connecting these. The adsorbent may be one that adsorbs carbon dioxide, carbon monoxide, moisture, and the like in the treated gas 112. Activated carbon, zeolite, alumina, and the like may be used as the adsorbent.

[0163] In a PSA hydrogen separator, one cycle of adsorption, desorption, and cleaning is performed repeatedly for one adsorption tower. Adsorption is a process in which carbon dioxide, carbon monoxide, etc. in the treated gas 112 are adsorbed onto an adsorbent, and hydrogen is extracted. Desorption is a process in which the pressure inside the adsorption tower is reduced, and carbon dioxide, carbon monoxide, etc. are desorbed from the adsorbent, and extracted as exhaust gas 114. Cleaning is a process in which the adsorption tower is cleaned with hydrogen.

[0164] A PSA hydrogen separator has a flow path for introducing treated gas 112 connected to the primary side, and a pipeline for discharging hydrogen 113 and a flow path for discharging exhaust gas 114 connected to the secondary side.

[0165] In the hydrogen production method shown in FIG. 12, the preferred flow shown in FIG. 6 can be carried out. First, in step S10, the reaction temperature T １ The dry reforming reaction is carried out at a reaction temperature T １ The reaction can be carried out by flowing the raw material gas 110 at a reaction temperature T １ Although there are no particular limitations on the reaction temperature, it is preferably equal to or higher than the activation temperature of the dry reforming catalyst. In one specific embodiment, it is preferably 600°C or higher, and more preferably 1100°C or lower, and more preferably 900°C or lower. １ can be adjusted by controlling the first temperature regulator 102 of the dry reforming reactor 103.

[0166] The method for adjusting the mixture ratio of methane and carbon dioxide in the raw material gas 110 is not particularly limited, but an example thereof is a method in which a raw material gas regulator having a gas mixer and a mass flow controller adjusts the mixture ratio of methane and carbon dioxide supplied via flow paths.

[0167] In addition, the reaction temperature T １ (°C), and CH in the source gas 110 ４ / CO ２ Once this is determined, the CO / CO ratio in the synthesis gas 111 can be calculated. ２ can be calculated.

[0168] Next, in step S11, a solid carbon capture reaction is carried out (solid carbon capture reaction step). The solid carbon capture reaction is carried out by heating the solid carbon collector 106 at a reaction temperature T ２ The solid carbon capture reaction can be carried out by flowing the synthesis gas 111 through the reaction vessel 110. It is preferable that the solid carbon capture reaction satisfies the following condition (1).

[0169]

[0170] In order to carry out the solid carbon capture reaction so as to satisfy the condition (1), the CH ４ / CO ２ , and reaction temperature T １ The composition of the synthesis gas 111 (CO / CO ２ ) based on the corresponding reaction temperature T ２ (° C.) and control the second temperature regulator 105 accordingly.

[0171] Next, in step S12, the treated gas 112 produced by the solid carbon capture reaction is separated into exhaust gas 114 and hydrogen 113 to obtain the hydrogen 113 (hydrogen separation step). The treated gas 112 is introduced into the hydrogen separator 107, which is operated under known conditions, whereby the hydrogen 113 can be separated.

[0172] Next, in step S13, heat is preferably recovered from the exhaust gas 114 (heat recovery step). Since the exhaust gas 114 contains carbon monoxide, hydrogen, and the like, heat can be recovered, for example, by burning these. The recovered heat is preferably used for the dry reforming reaction and / or the solid carbon capture reaction.

[0173] However, the reaction temperature T １ The control of step S11, the condition (1) in step S11, and the heat recovery in step S13 are optional and may not be performed.

[0174] According to the flow shown in FIG. 6, the CO / CO ２ and reaction temperature T ２ By adjusting the temperature and pressure within an appropriate range, when producing hydrogen from a raw material gas containing methane and carbon dioxide, CO ２ This is preferable because it can significantly reduce emissions.

[0175] 13 shows the basic configuration of a hydrogen production apparatus for carrying out a hydrogen production method according to a second embodiment. The hydrogen production method of the present invention includes a dry reforming reaction step 103 in which a synthesis gas 111 containing carbon monoxide and hydrogen is obtained from a raw material gas 110 containing methane and carbon dioxide in the presence of a dry reforming catalyst, a solid carbon collection step 106 in which the synthesis gas 111 from the dry reforming reaction step 103 is introduced and solid carbon is generated from the carbon monoxide in the synthesis gas in the presence of a solid carbon collection catalyst to obtain a treated gas 112, and a hydrogen separation step 107 in which hydrogen 113 is extracted from the treated gas 112 from the solid carbon collection step 106 to obtain an exhaust gas 114 containing carbon dioxide, and the exhaust gas 114 from the hydrogen separation step 107 is introduced into the dry reforming reaction step 103 to circulate the carbon dioxide without discharging it to the outside.

[0176] The hydrogen production apparatus of the second embodiment includes a dry reforming reactor 103 that produces a synthesis gas containing carbon monoxide and hydrogen from a raw material gas 110 containing methane and carbon dioxide in the presence of a dry reforming catalyst; a solid carbon collector 106 that receives the synthesis gas 110 from the dry reforming reactor 103, generates solid carbon from the carbon monoxide in the synthesis gas in the presence of a solid carbon collection catalyst, and produces a treated gas 112; and a hydrogen separator 107 that extracts hydrogen 113 from the treated gas 112 from the solid carbon collector 106, and produces an exhaust gas 114 containing carbon dioxide. The dry reforming reactor 103 is provided with a first flow path 115a for supplying the synthesis gas 111 from the dry reforming reactor 103 to the solid carbon collector 106, a second flow path 115b for supplying the treated gas 112 from the solid carbon collector 106 to the hydrogen separator 107, and a third flow path 115c for supplying the exhaust gas 114 from the hydrogen separator 107 to the dry reforming reactor 103, and is characterized in that carbon dioxide is circulated internally without being discharged to the outside.

[0177] The exhaust gas 114 containing carbon dioxide is circulated to the DRM reactor 103 via the third flow path 115c connecting the hydrogen separator 107 and the DRM reactor 103, so that the carbon dioxide contained in the exhaust gas 114 is not discharged outside the hydrogen production device, thereby reducing the amount of carbon dioxide discharged outside the system.

[0178] The hydrogen production method and apparatus of the second embodiment circulates carbon dioxide internally without emitting it to the outside, thereby reducing the amount of carbon dioxide emitted outside the system compared to conventional hydrogen production methods and apparatuses, and producing hydrogen that is equal to or better than conventional methods and apparatuses.

[0179] [Third Embodiment] Fig. 14 shows a block diagram of a hydrogen production apparatus for carrying out a hydrogen production method of a third embodiment. The hydrogen production method shown in Fig. 14 is the hydrogen production method shown in Fig. 13 in which methane is combusted to generate heat and carbon dioxide, the generated heat is introduced into the dry reforming reaction step, the feed gas containing carbon dioxide in an amount equal to the generated carbon dioxide is introduced into the dry reforming reaction step, and in the solid carbon capture step, carbon in an amount equal to the total amount of carbon contained in the carbon dioxide and methane in the feed gas is captured as solid carbon.

[0180] The hydrogen production apparatus shown in FIG. 14 is the same as the hydrogen production apparatus shown in FIG. 13 , but further includes a methane combustion furnace 108 and a heat supply passage 108 a that supplies heat from the methane combustion furnace 108 to the dry reforming reactor 103 .

[0181] In the hydrogen production method and apparatus shown in Figure 14, the amount of carbon dioxide contained in the raw material gas is equal to the amount of carbon dioxide emitted to the outside of the system during methane combustion, making it possible to produce hydrogen without emitting carbon dioxide during methane combustion.

[0182] [Fourth embodiment] A block diagram of a hydrogen production apparatus for carrying out a hydrogen production method according to a fourth embodiment is shown in Fig. 15. The hydrogen production method shown in Fig. 15 is the hydrogen production method shown in Fig. 13 , and further includes extracting and combusting a portion of the hydrogen 113 separated in the hydrogen separation step 107, and supplying the generated heat to the dry reforming reaction step 103.

[0183] The hydrogen production apparatus shown in Figure 15 is characterized in that, in the hydrogen production apparatus shown in Figure 13, it further comprises a hydrogen extraction passage 116 that extracts a portion 113a of hydrogen from the hydrogen separator 107, a hydrogen combustion furnace 109 that combusts hydrogen, and a heat supply passage 109a that supplies heat from the hydrogen combustion furnace 109 to the dry reforming reaction channel 103.

[0184] The hydrogen production method and apparatus of this embodiment eliminate the need for at least a portion of carbon dioxide as a feed gas, and enable hydrogen production by methane reforming without emitting carbon dioxide. Note that, although Fig. 15 shows a configuration in which a hydrogen combustion furnace 109 and a heat supply line 109a are provided in the hydrogen production apparatus of the second embodiment (basic configuration) shown in Fig. 13, these may also be provided in the hydrogen production apparatus shown in Fig. 14.

[0185] [Fifth Embodiment] The hydrogen production method shown in FIG. 16 is the hydrogen production method shown in FIG. 13 , in which heat is recovered from the exhaust gas 114 and supplied to the dry reforming reaction step 103 before the exhaust gas 114 from the hydrogen separation step 107 is introduced into the dry reforming reaction step 103.

[0186] 16 is the same as the hydrogen production apparatus shown in Fig. 13 , except that a heat recovery unit 204 that recovers heat from the exhaust gas 114 is connected to the third flow path 115c, and the heat recovered by the heat recovery unit 204 is supplied to the dry reforming reactor 103. The heat recovery unit 204 can be a combustion furnace that introduces oxygen and combusts the exhaust gas 114, or a fuel cell.

[0187] The hydrogen production method and apparatus of this embodiment can reduce the energy introduced from outside the system by utilizing the heat recovered by the heat recovery unit for the dry reforming reaction. Note that, although Fig. 16 shows a configuration in which a heat recovery unit 204 is provided in the hydrogen production apparatus of the second embodiment (basic configuration) shown in Fig. 13, the heat recovery unit 204 may also be provided in addition to the hydrogen production apparatus shown in Fig. 14 or 15.

[0188] Sixth Embodiment A hydrogen production apparatus 200 shown in FIG. 17 is the hydrogen production apparatus shown in FIG. 16 , and includes a raw material gas regulator 205 and a control device 201 that controls the gas flow rate of the raw material gas regulator 205 and the temperatures of the DRM reactor 103 and the solid carbon collector 106.

[0189] Of these, the raw material gas regulator 205, the DRM reactor 103, the solid carbon collector 106, and the hydrogen separator 107 are connected in sequence (in series), and the primary side of the heat recovery unit 204 is connected to a third flow path 115c for the exhaust gas 114 that branches off from the hydrogen separator 107. The third flow path 115c connected to the secondary side of the heat recovery unit 204 joins the raw material gas regulator 205 and the DRM reactor 103.

[0190] The heat recovery device 204 has a function of recovering heat from methane, carbon monoxide, hydrogen, etc. that may be contained in the exhaust gas 114 generated when the hydrogen 113 is separated from the treated gas 112 by the hydrogen separator 107. Specifically, the heat recovery device 204 may be a burner that combusts the exhaust gas 114, a fuel cell that uses the exhaust gas 114 as fuel, or the like.

[0191] The heat recovered by the heat recovery device 204 is preferably used to control the temperature of the DRM reactor 103 and / or the solid carbon collector 106 (heat transfer is indicated by the symbol "Q" in the drawing). The circulating gas 120 discharged from the heat recovery device 204 contains carbon dioxide, which is mixed with the raw material gas 110 for use.

[0192] As will be described later, the hydrogen production device 200 can reduce CO generated during hydrogen production. ２ In one embodiment, the amount of CO contained in the circulation gas 120 is significantly reduced. ２ is the CO in the raw material gas 110 ２ Since the amount is less than the required amount, ２ While supplying CO ２ It is also possible to operate the system in a circulating manner without discharging the wastewater.

[0193] The raw material gas regulator 205 has a function of mixing the methane 121 and the carbon dioxide 122 to adjust the composition of the raw material gas 110. The raw material gas regulator 205 may be configured by a gas mixer that mixes the methane 121 and the carbon dioxide 122 supplied through a flow path at an arbitrary ratio, a mass flow controller, and the like.

[0194] The hydrogen production device 200 has a control device 201. The control device 201 is a computer including a processor 202 and a memory 203. The control device 201 controls the DRM reactor 103, the solid carbon collector 106, and the raw material gas regulator 205. In addition to the above, the hydrogen separator 107 and the heat recovery device 204 may also be controlled.

[0195] The control device 201 has a plurality of sensors for detecting the operating state of the hydrogen production device 200. Detection signals from the plurality of sensors are input to the control device 201. The control device 201 controls the reaction temperature T １ a temperature sensor (TEMP1) 130 for detecting the reaction temperature T of the solid carbon capture reaction in the solid carbon collector 106; ２ and a flow rate sensor (FLOW) 132 that detects the mixture ratio of methane 121 and carbon dioxide 122 in the raw material gas regulator 205.

[0196] TEMP1 and TEMP2 may directly detect the temperatures of the gases in the DRM reactor 103 and the solid carbon collector 106, or may estimate each temperature from physical quantities such as the outputs of the first temperature controller 102 and the second temperature controller 105 and the operating time.

[0197] The control device 201 controls, for example, the reaction temperature T １ The detection signal of the temperature sensor (TEMP1) 130 is acquired, and the output of the first temperature regulator 102 of the DRM reactor 103 is adjusted based on the acquired information.

[0198] The control device 201 includes a processor 202, which is a hardware device, and the processor 202 may be a processor core that executes a program stored in a memory. Such a processor core may be a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit).

[0199] The processor 202 may be a hardware logic circuit including a programmed logic unit. The digital circuit may be a logic circuit array, such as an ASIC (Application-Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), an SoC (Systemona Chip), a PGA (Programmable Gate Array), and a CPLD (Complex Programmable Logic Device).

[0200] The control device 201 includes a memory 203. The memory is a non-transient, tangible storage medium that non-temporarily stores a program and / or data that can be read by the processor. The storage medium is provided by a semiconductor memory, a magnetic disk, an optical disk, or the like. The program may be distributed independently or as a storage medium on which the program is stored. The processor 202 may also be a combination of a processor core and a hardware logic circuit.

[0201] The hydrogen production device 200 can perform the hydrogen production flow shown in Fig. 8. In step S20, the control device 201 controls the first temperature regulator 102 and the raw material gas regulator 205 to adjust the reaction temperature T １ The DRM reaction is carried out at (°C).

[0202] Specifically, the state at the time of DRM reaction is CH ４ / CO ２ is acquired by the flow rate sensor (FLOW) 132, and the reaction temperature T １ (°C) is acquired by the temperature sensor (TEMP1) 130. ４ / CO ２ is adjusted by the raw material gas regulator 205, and the reaction temperature T １ is adjusted by the first temperature adjuster 102.

[0203] In addition, when the raw material gas 110 is prepared by merging the circulating gas 120, the CO ２ Based on the content of ４ / CO２ The CO in the circulation gas 120 may be adjusted. ２ The content of can be calculated from the composition of the raw material gas 110 used in its production, but a sensor for measuring the composition of the circulating gas 120 may be provided midway through the flow path 115, and the control device 201 may acquire the measured value and use it to control the raw material gas regulator 205.

[0204] In this step S20, a synthesis gas 111 containing hydrogen and carbon monoxide is obtained from a raw material gas 110 containing methane and carbon dioxide.

[0205] Next, in step S21, the control device 201 controls the second temperature regulator 105 to perform a solid carbon capture reaction so as to satisfy the condition (1). ４ / CO ２ CO / CO of syngas 111 calculated from ２ , the reaction temperature T acquired by the temperature sensor (TEMP1) 130 １ (°C), and the reaction temperature T obtained by the temperature sensor (TEMP2) 131 ２ Based on the temperature (°C), the control device 201 determines whether the reaction conditions of the solid carbon capture reaction satisfy condition (1), and controls the outputs of the raw material gas regulator 205, the first temperature regulator 102, and the second temperature regulator 105 so as to satisfy this condition, thereby adjusting the CO / CO ２ , reaction temperature T １ , and reaction temperature T ２ Adjust.

[0206] In step S21, solid carbon is separated from the synthesis gas 111 containing carbon monoxide, and a treated gas 112 containing carbon dioxide, etc. is obtained. Note that the treated gas 112 may contain methane, carbon monoxide, water vapor, hydrogen, etc. in addition to carbon dioxide.

[0207] Next, in step S22, hydrogen 113 is separated and obtained from the treated gas 112 by the hydrogen separator 107, and an exhaust gas 114 is also obtained.

[0208] Next, in step S23, the heat recovery unit 204 recovers heat from the exhaust gas 114, generating a circulation gas 120. The heat Q generated in step S23 is supplied to the DRM reactor 103 and / or the solid carbon collector 106, and is used to adjust the reaction temperatures.

[0209] The circulating gas 120 generated in step S23 is passed through a flow path to join the raw material gas regulator 205 and the DRM reactor 103, and is used as part of the raw material gas 110.

[0210] The flow of the control process executed by the control device 201 in the above-mentioned step S21 may be the flow diagram shown in Fig. 9. The control device 201 controls the reaction conditions of the DRM reaction and the solid carbon capture reaction by executing the above-mentioned control process. ２ emissions will be significantly reduced.

[0211] In step S30, the control device 201 acquires information about the operating state of the hydrogen production device 200. Specifically, the temperature sensor (TEMP1) 130 detects the temperature of the gas inside the DRM reactor 103 (reaction temperature T １ In addition, the flow rate sensor (FLOW) 132 acquires the flow rates (mixing ratio) of methane and carbon dioxide in the raw material gas regulator 205 .

[0212] In step S31, the control device 201 controls the CH ４ / CO ２ Ratio and reaction temperature T １ (°C), the CO / CO in the synthesis gas ２ Calculate CO / CO ２ is calculated based on the CH ４ / CO ２ , and reaction temperature T １ This is done by heat balance calculation based on the above. Software programs such as "COCO" can be used for this calculation.

[0213] Next, in step S32, the control device 201 detects the temperature of the gas in the solid carbon collector 106 (reaction temperature T ２ ) to obtain the

[0214] Next, in step S33, the control device 201 determines the CO / CO ratio in the synthesis gas 111 introduced into the solid carbon collector 106. ２ and the reaction temperature T １ (°C) and reaction temperature T ２ (° C.) satisfies condition (1).

[0215] Specifically, in step S33, the determination is made through the following steps: １ Based on the calculated CO / CO ratio, the Inflection and Gradient are calculated from Equations (2) and (3). Next, the sigmoid curve on the right side of the inequality sign on the right side of Condition (1) is obtained from the calculated Inflection and Gradient. ２ and the obtained reaction temperature T ２ Based on these, it is determined whether the value is within the range of the sigmoid curve.

[0216]

[0217]

[0218] If the result of the above determination is that the condition (1) is not satisfied (step S33: NO), in steps S34 to S36, the reaction temperature T １ (Step S34), and based on the detection signal of the flow rate sensor (FLOW) 132, the raw material gas regulator 205 controls the flow rates (mixing ratio) of methane and carbon dioxide in the raw material gas 110 (Step S35), and based on the detection signal of the temperature sensor (TEMP2) 131, the second temperature regulator 105 controls the reaction temperature T ２ (step S36).

[0219] Thereafter, steps S30 to S32 are repeated, and the determination in step S33 is made. Steps S34 to S36 and steps S30 to S33 are repeated until condition (1) is satisfied.

[0220] On the other hand, if the result of the judgment in step S33 is that condition (1) is satisfied (step S33: YES), the control processing by the control device 201 ends, and the process returns to FIG. 8, and the subsequent steps (step S22 and step S23) are executed.

[0221] The hydrogen production device 200 has a control device 201, and the control device 201 controls the CO / CO ratio in the synthesis gas 111. ２ , and reaction temperature T ２ Since each part is controlled to satisfy condition (1), the amount of carbon dioxide emitted to the outside of the device when hydrogen is produced from the raw material gas is significantly reduced. In addition, since the hydrogen production device 200 has a heat recovery device 204, heat can be recovered from the hydrogen and carbon monoxide contained in the exhaust gas 114 and used for the DRM reaction and / or the solid carbon capture reaction, which also reduces the amount of carbon dioxide emitted due to heating, etc. (or the generation of electricity for that purpose).

[0222] Furthermore, the hydrogen production device 200 has a flow path that merges the circulating gas 120 with the raw material gas 110. In one embodiment, the carbon dioxide content in the circulating gas 120 is less than the (required) carbon dioxide content in the raw material gas, so that hydrogen production can be performed without discharging carbon dioxide used in the process outside the device, in other words, while constantly supplying carbon dioxide from outside the device.

[0223] In the hydrogen production device 200, the various parts (components) are connected by the flow paths 115 as described above, but the connection form (connection paths) of the various parts in the hydrogen production device 200 is not limited to the above.

[0224] For example, the hydrogen separator 107 may be disposed between the DRM reactor 103 and the solid carbon collector 106. Also, a plurality of one or more types of components may be disposed, in which case the flow path 115 may branch and the same type of components may be arranged in parallel, or the same type of components may be arranged consecutively.

[0225] In addition to the above, the hydrogen production device 200 may further include one or more valves, water vapor removers, pressure regulators (pressure reducing valves, compressors), heat exchangers, etc., within the scope of the effects of the present invention.

[0226] Seventh Embodiment The hydrogen production method or hydrogen production device shown in FIG. 18 is the hydrogen production method or hydrogen production device shown in FIG. 13, further including a compressor 401 in the first flow path 115a.

[0227] When the above-mentioned hydrogen separation membrane is used as the hydrogen separator 107, a low hydrogen partial pressure reduces the amount of hydrogen extracted. Also, when the above-mentioned PSA hydrogen separator is used as the hydrogen separator 107, a low inlet pressure of the adsorbent in the hydrogen separator 107 reduces the amount of hydrogen extracted. In response to these issues, the hydrogen production method or hydrogen production apparatus of this embodiment further includes a compressor 401 in the first flow path 115a, thereby increasing the amount of hydrogen extracted in the hydrogen separator 107.

[0228] The compressor 401 is not particularly limited, but may include or consist of a positive displacement compressor, a turbo compressor, or a combination of two or more of these. Among these, a positive displacement compressor is preferred. By using a positive displacement compressor, it is possible to achieve a high compression ratio with a small number of stages.

[0229] 18 preferably further comprises a heat exchanger HE that converts heat generated in the solid carbon collector 106 into steam and supplies the steam to the compressor 401. The heat generated in the solid carbon collector 106 can be converted into steam V by the heat exchanger HE, and the steam V can be supplied to the compressor 401.

[0230] The solid carbon capture reaction is an exothermic reaction, and the heat generated by the reaction can be used to drive the compressor 401, thereby reducing the consumption of power for driving the compressor.

[0231] In the hydrogen production method or hydrogen production apparatus shown in Figure 18, it is preferable to provide a pressure adjustment valve 402 at the inlet of the hydrogen separator 107 in the second flow path 115b, and to provide a gas holder 403 and a pressure adjustment valve 404 in the third flow path 115c.

[0232] When the first flow path 115a includes a compressor 401, by providing a pressure regulating valve 402 at the inlet of the hydrogen separator 107, it is possible to control the conditions for separating and extracting hydrogen in the hydrogen separator 107. Furthermore, when merging the exhaust gas 114 from the hydrogen separator 107 into the inlet of the dry reforming reactor 103, it may be difficult to achieve this if the exhaust gas 114 remains pressurized. By providing a pressure regulating valve 404 for decompressing the exhaust gas 114 and a gas holder 404 for holding the gas in the third flow path 115c, it is possible to make it easier for the exhaust gas 114 to be merged into the inlet of the dry reforming reactor 103.

[0233] The pressure regulating valves 402 and 404 are not particularly limited, and can be operated by appropriately using a primary valve and a secondary valve.

[0234] There is no particular limitation on the gas holder 403. By using a gas holder, pressure fluctuations can be reduced.

[0235] The hydrogen production method or hydrogen production device shown in FIG. 18 preferably further comprises a water supply passage W for supplying water generated in the dry reforming reactor 103 to the solid carbon collector 106 .

[0236] Since water is generated in the dry reforming reaction, it is necessary to extract the water. By using the water extracted and condensed from the dry reforming reactor 103 as cooling water for controlling the temperature of the solid carbon capture reaction, the consumption of cooling water can be reduced.

[0237] In the hydrogen production method or hydrogen production apparatus shown in FIG. 18, it is preferable to provide a compressor 401 in the first flow path 115a and further provide a steam supply path that supplies steam V generated in the solid carbon collector 106 to the compressor 401.

[0238] The steam generated by the solid carbon capture reaction can be used to drive the compressor 401 provided in the first flow path 115a, and the consumption of power for driving the compressor 401 can be reduced.

[0239] Although Fig. 18 shows a configuration including all of the compressor 401, pressure regulating valve 402, gas holder 403 and pressure regulating valve 404, heat exchanger HE, water supply channel W, and steam supply channel, a configuration including only compressor 401 is also possible, and the other components are preferably included in an apparatus including compressor 401, and it is not necessary to include all of them. Also, Fig. 18 shows a configuration including compressor 401, pressure regulating valve 402, gas holder 403 and pressure regulating valve 404, heat exchanger HE, water supply channel W, and steam supply channel, based on the hydrogen production apparatus shown in Fig. 13, but these can also be included in the hydrogen production apparatus shown in Figs. 14 to 16.

[0240] [Modification 1 of Solid Carbon Collector] Figure 19 shows Modification 1 of the solid carbon collector. When a compressor 401 is provided in the first flow path 115a, the first flow path 115a downstream of the compressor 401 can be branched to arrange multiple solid carbon collectors 106 in parallel, and valves 405A, 405B, and 405C can be provided at the inlet of each solid carbon collector 106A, 106B, and 106C, and valves 406A, 406B, and 406C can be provided at the outlet. Note that although Figure 19 shows three combinations of solid carbon collectors and valves, the number of sets is not limited to this.

[0241] By arranging multiple solid carbon collectors in parallel, it is possible to discharge solid carbon by closing the inlet valve of at least one of the multiple solid carbon collectors while continuing operation of the other solid carbon collectors, thereby enabling carbon collection while continuously operating the hydrogen production system.

[0242] 19, in the solid carbon collector 106C, the inlet valve 405C is closed and the outlet valve 406C is open, and solid carbon is discharged from the solid carbon collector 106C. At the same time, the solid carbon collectors 106A and 106B continue to operate and collect solid carbon.

[0243] In FIG. 19, it is preferable to further provide a buffer tank 407 in the first flow path 115a downstream of the compressor 401 and upstream of the branch.

[0244] When solid carbon is discharged from at least one of the solid carbon collectors 106A, 106B, and 106C, pressure fluctuations may occur in the other solid carbon collectors. By providing a buffer tank 407 in the first flow path 115a downstream of the compressor 401 and upstream of the branch, it is possible to buffer the pressure fluctuations described above.

[0245] The buffer tank 407 provided in front of the plurality of solid carbon collectors is not particularly limited.

[0246] [Modification 2 of Solid Carbon Collector] Figure 20 shows Modification 2 of the solid carbon collector. As shown in Figure 20, a compressor 401 may be further provided in the first flow path 115a, a plurality of the solid carbon collectors 106D, 106E may be arranged in series, and a gas composition adjusting unit 408 may be provided between each solid carbon collector.

[0247] By arranging a plurality of solid carbon collectors 106D, 106E in series, the amount of carbon captured in the entire hydrogen production apparatus can be increased. In this case where a plurality of solid carbon collectors 106D, 106E are arranged in series, when carbon is captured in the upstream solid carbon collector 106D, the concentration of carbon monoxide in the downstream solid carbon collector 106E decreases and the concentration of carbon dioxide increases, making it difficult for a reaction to occur in the downstream solid carbon collector 106E. By providing a gas composition adjusting unit 408 at the outlet of each solid carbon collector and adjusting the gas composition to one that makes it easy for a reaction to occur in the downstream solid carbon collector, the capture efficiency in the downstream solid carbon collector can be improved. For example, when the inlet gas (CH ４ :CO２ : H ２ :CO:H ２ When CO₂ → C + CO₂ → ... ２ (Reaction (1)) occurs. As a result, the outlet gas (CH ４ :CO ２ : H ２ :CO:H ２ O = 10:35:25:15:5 (molar ratio)) is released, and the CO concentration in the outlet gas is reduced compared to the inlet gas, and CO ２ If the outlet gas is introduced directly into the solid carbon collector 106E, the CO concentration decreases and the CO ２ As the concentration increases, the reaction (1) in the solid carbon collector 106E becomes less likely to occur than the reaction (1) in the solid carbon collector 106D. ２ At least a part of the CO contained in the outlet gas is recovered in the gas composition adjusting unit 408. ２ The CO concentration is reduced and the CO concentration is relatively increased, which makes the reaction (1) in the solid carbon collector 106E more likely to occur, and as a result, the carbon capture efficiency in the solid carbon collector 106E can be improved. ２ can be reused as a component of the raw material gas 110 introduced into the DRM reactor 103.

[0248] The gas composition adjustment unit 408 can include or consist of, but is not limited to, a gas separation membrane, a gas adsorption / desorption system, or a combination of two or more of these. Among these, a gas separation membrane is preferred. The use of a gas separation membrane can provide the effect of reducing the footprint and / or optimizing energy costs.

[0249] FIG. 21 is a graph showing the equilibrium carbon deposition composition of synthesis gas at different temperatures in a solid carbon trap. In FIG. 21, the horizontal axis represents the ratio of moles of oxygen to moles of carbon (O / C), and the vertical axis represents the ratio of moles of hydrogen to moles of carbon (H / C). In FIG. 21, the temperature (400, 500, 600, or 700°C) indicates the temperature in the solid carbon trap. The lower left region of each temperature curve in FIG. 21 is the region where the carbon capture reaction occurs, and the upper right region of the curve is the region where the carbon capture reaction does not occur. For example, in the 400°C curve in FIG. 21, the moles of carbon decrease when the solid carbon trap is trapped, so both the O / C ratio and the H / C ratio increase, and as shown by the arrows in FIG. 21, the region moves from the region where the carbon capture reaction occurs to the region where the carbon capture reaction does not occur. If such a change occurs in the upstream solid carbon collector 106D, the solid carbon collection reaction will be difficult to occur in the downstream solid carbon collector 106E. Therefore, the gas composition adjuster 408 is used to adjust the gas composition according to the temperature in the downstream solid carbon collector 406E, so that the reaction will occur in the downstream solid carbon collector 106E.

[0250] [Hydrogen production apparatus (modification)] Fig. 22 is a block diagram of a modification of the hydrogen production apparatus of the present invention. The hydrogen production apparatus 200 already described has a DRM reactor 103 that performs the DRM reaction and a solid carbon collector 106 that performs the solid carbon capture reaction, but the hydrogen production apparatus 300 in Fig. 22 has a reactor 301 that functions as both the DRM reactor and the solid carbon collector instead.

[0251] A DRM catalyst 101 and a solid carbon capture catalyst 104 are disposed inside the reactor 301, and a raw material gas 110 introduced from the primary side first comes into contact with the DRM catalyst 101 to generate a synthesis gas 111. The synthesis gas 111 then comes into contact with the solid carbon capture catalyst 104 to generate a treated gas 112. The above reactions occur sequentially inside the reactor 301.

[0252] The temperature inside the reactor 301 is adjusted by a third temperature regulator 302 controlled by the control device 201, and the reaction temperature T １ , and reaction temperature T ２are acquired by a temperature sensor (TEMP1) 130 and a temperature sensor (TEMP2) 131.

[0253] A specific example of the reactor 301 is a reactor having one reaction tube, a DRM catalyst 101 and a solid carbon capture catalyst 104 packed in this order in the reaction tube, and a heater for adjusting the temperature of the reaction tube.

[0254] The reactor 301 of the hydrogen production device 300 has a third temperature regulator 302 that regulates the temperature of the entire reactor. １ ) and a first temperature controller 102 that independently controls the temperature of the solid carbon capture reaction (reaction temperature T ２ ) and a second temperature regulator 105 that independently controls the first temperature regulator 102, and these may be controlled by the control device 201.

[0255] The hydrogen production device 300 has a reactor 301 that serves both as a DRM reactor and a solid carbon collector, and is further configured so that the reaction temperature is controlled by a third temperature regulator 302, which has the advantage of being simpler in structure and easier to control. １ , and reaction temperature T ２ When the temperature is controlled to 600 to 620°C, the above tendency is more pronounced.

[0256] [Temperature Control of Dry Reforming Reaction and Solid Carbon Capture Reaction] In the hydrogen production method of the present invention shown in FIG. 12, the molar ratio of carbon monoxide content to carbon dioxide content in the synthesis gas (CO / CO ２ ) and the reaction temperature T １ (°C), the reaction temperature T of the solid carbon capture reaction ２ (° C.) and are preferably controlled so as to satisfy the following condition (1).

[0257]

[0258] The meaning of the above condition (1) and the CO / CO ratio in the synthesis gas are as follows: ２ and reaction temperature T １ , T ２ The mechanism by which the effects of the present invention are achieved by controlling the relationship between the above and the above will be explained.

[0259] In FIG. 12, the DRM reactor 103 is configured by a dry reforming catalyst 101 (hereinafter also referred to as the “DRM catalyst”) and a temperature of the gas flowing through the DRM reactor 103 (reaction temperature T １ The solid carbon collector 106 includes a first temperature controller 102 for controlling the temperature (reaction temperature T ２ and a second temperature regulator 105 for controlling the temperature of the first temperature regulator 102.

[0260] The dry reforming reactor 103 is configured to have a reaction temperature T １ There are no particular limitations on the type of device as long as it can bring the raw material gas 110 (raw material gas flow) into contact with the dry reforming catalyst 101. For example, the device may be configured to include a container through which the raw material gas 110 can flow, the dry reforming catalyst 101 fixed in the container, and a first temperature regulator 102 which is a heater.

[0261] The solid carbon collector 106 is a solid carbon collector catalyst 104 and a reaction temperature T ２ Specifically, the reactor includes a reaction tube, a solid carbon capture catalyst 104 accommodated in the reaction tube, and the second temperature regulator 105 which is a heater arranged around the reaction tube, and a first flow path 115a for introducing a synthesis gas 111 is connected to the upstream (primary) side of the reaction tube, and a second flow path 115b for discharging a treated gas 112 is connected to the downstream (secondary) side of the reaction tube.

[0262] Next, in the production of hydrogen using this hydrogen production device 100, CO as part of the raw material gas 110 ２ and the amount of CO in the exhaust gas 114 ２ The balance of the derived amounts will be explained. ２ The derived amount of CO may be contained in the exhaust gas 114 and may be CO ２ The calculation also takes into account the effect of CO, which may cause

[0263] First, the DRM reactor 103 was charged with 100 mmol / min of CH ４ and CO ２A case will be considered in which a raw material gas 110 (135 L / h) containing the above-mentioned mixed gas is introduced and flows from the upstream to the downstream of the flow path 115 of the hydrogen production device 100. Here, the DRM reactor 103 is maintained at 600° C., that is, the reaction temperature T １ is set to 600°C.

[0264] Assuming that thermodynamic equilibrium exists between the DRM catalyst 101 and the gas flow in the DRM reactor 103, the composition of the synthesis gas 111 can be estimated by heat balance calculation.

[0265] As an example, the composition of the raw material gas 110 flowing into the hydrogen production device 100 is set to a volume ratio of CH ４ :CO ２ = 1:9 (14:121 (L / hr)), the composition of the synthesis gas 111 is CH ４ : H ２ :CO ２ :CO:H ２ CO / CO = 1:13:96:38:12 (L / hour). ２ becomes 0.396.

[0266] For this synthesis gas, solid carbon capture was performed at T ２ = 600 ° C., and CO and CH contained in the exhaust gas after hydrogen separation ４ is burned, and CO ２ When the CO contained in the gas released to the outside of the device is ２ The amount of CO introduced into the hydrogen production device is 121 (L / h). ２ and the amount of CO emitted ２ The amounts are mathematically equal.

[0267] Reaction temperature T １ and T ２ and CO / CO in the synthesis gas. ２ If the CO introduced into the hydrogen production device is 0.953, ２ The CO / CO ratio is 101 L / hour, while the CO / CO ratio is 105 L / hour. ２ If the inflow rate is 90 L / hour, the discharge rate is 103 L / hour. ２If the ratio is 1.53, the discharge amount is 102 L / hour for an inflow amount of 81 L / hour.

[0268] On the other hand, the reaction temperature T １ at 600°C, and reaction temperature T ２ is 451°C, the CO / CO ２ CO when set to 0.396 ２ The amount of discharged water is 116 L / hour. In this case, the amount of discharged water is smaller than the amount of inflow of 121 L / hour.

[0269] A hypothetical mechanism for obtaining the above thermodynamic response will be explained. Figure 2 shows the Boudouard reaction (2CO → CO ２ 2. In FIG. 2, the open (open) circular symbols and the closed (black) circular symbols represent the reaction temperature T ２ CO in the treated gas 112 (outgoing gas, labeled "Outgas" in the figure) ２ , and the mole fraction of CO (vertical axis: left). The open square symbols indicate the reaction temperature T ２ CO / CO in the treated gas 112 (°C) ２ (vertical axis: right).

[0270] According to Fig. 2, the light-off temperature (activation temperature) can be theoretically estimated to be 450°C. In this specification, the light-off temperature (activation temperature) is calculated based on the total amount of CO and CO ２ The reaction temperature T ２ This means the lowest temperature at which the amount of CO contained in the treated gas 112 changes from zero to a significant value when the temperature is gradually increased from 350°C.

[0271] Also, according to FIG. 2, the reaction temperature T ２ According to the change in the equilibrium, the equation is: 2CO → CO ２ +C from right to left, and CO and CO in the treated gas 112 ２ The mole fraction of CO ２It can be seen that the ratio of CO changes from about 0.5:0.0 to about 0.0:1.0.

[0272] That is, the reaction temperature T ２ As the temperature is gradually increased, the equilibrium of the Boudouard reaction shifts from right to left, and the amount of CO contained in the treated gas 112 also increases. ２ By reducing this CO2 emission, the final CO2 ２ can reduce emissions.

[0273] CO outside the hydrogen production device ２ The discharge amount of CH contained in the treated gas 112 is ４ It is also affected by the amount of CH ４ If it contains CH ４ does not contribute to the solid carbon capture reaction and is emitted into the treated gas 112. When this is burned, CO ２ The CH in the synthesis gas 111 ４ The amount of CH that was not used in the DRM reaction is, so to speak, the remaining CH ４ This is also possible, and adjustments are necessary.

[0274] The present inventors have determined that the reaction temperature T ２ , and CO / CO in the synthesis gas 111 ２ By controlling within a predetermined range, CO ２ The conditions under which the derived amount is equal to or less than the introduced amount were searched for. As a result, it was noticed that the "range" formed a continuous region, and the reaction temperature T １ , reaction temperature T ２ , and CO / CO in the synthesis gas 111 ２ The relationship between was further examined.

[0275] Specifically, the reaction temperature T １ , T ２ The same calculations as above were performed while changing the reaction temperature T １ , reaction temperature T ２ , and CO / CO in the synthesis gas 111２ FIG.

[0276] In FIG. 3, the horizontal axis indicates "CO / CO ２ "Ratio in DRM Outgas" is the CO / CO ratio in the synthesis gas 111. ２ The vertical axis "CO Disprop. Temperature (°C)" represents the reaction temperature T ２ Each plot represents the "DRM Temperature", i.e., the reaction temperature T １ In CO ２ This is the point at which the amount derived is theoretically equal to the amount introduced.

[0277] For example, the reaction temperature T １ When the temperature is 600°C, in the inner area of ​​each plot (towards the origin), ２ The amount of outflow is smaller, typically less than the amount of inflow. １ As the CO ２ It can be seen that the area defined by each plot where the derived amount is equal to the introduced amount becomes larger.

[0278] From FIG. 3, each reaction temperature T １ In CO ２ We hypothesized that the set of points where the amount of output is equal to the amount of input follows a sigmoid curve. Furthermore, this sigmoid curve follows the reaction temperature T １ As the value of σ increases, the slope (absolute value) decreases and the inflection point moves in the positive direction of the horizontal axis.

[0279] Specifically, the reaction temperature T １ CO ２ The "COCO" software calculates the region where the derived amount is equal to the introduced amount, and the region where the following condition (1) is met:

[0280] Inflection refers to the inflection point (horizontal axis) of the sigmoid curve, and gradient refers to the inclination of the slope.

[0281]

[0282] Table 2 shows the reaction temperature T １ The values ​​of 600° C., 700° C., and 900° C. were obtained by fitting.

[0283] From the results in Table 2 and Figure 3, it can be seen that the Inflection and Gradient are related to the reaction temperature T １ 4 shows a diagram illustrating this relationship.

[0284] In FIG. 4, the horizontal axis represents the reaction temperature T １ The triangle plots represent the inflection, and the square plots represent the gradient. The relational equations obtained from fitting each plot were as follows: １ (°C) is preferably 600°C or higher.

[0285]

[0286] That is, each reaction temperature T １ In CO ２ It has been found that the region where the amount of derived is significantly reduced, typically the region where the amount of introduced is smaller, is the region that satisfies the following condition (1).

[0287]

[0288] From the above equations (2) and (3), the reaction temperature T １ The inflection and gradient when sim800°C were calculated (the results are shown in Table 2), and the sigmoid curve on the right side of the inequality sign on the right side of (1) obtained as a result is the curve represented by "sim800°C" in Figure 3. This curve matches the plots obtained by separate calculations, and it was found that the above condition settings were correct.

[0289] From the above, if the manufacturing method satisfies condition (1), the amount of CO emitted outside the device ２ The amount of CO is significantly reduced, typically ２It was found that the amount introduced and the amount derived were equal or less than each other.

[0290] It is easy for a person skilled in the art to operate the hydrogen production device 100 under such conditions because the temperature of the dry reforming reaction (reaction temperature T １ ) is determined, the CO / CO ratio in the DRM outgas (i.e., syngas 111) is ２ is the CH in the source gas 110 ４ / CO ２ This is because it can be easily adjusted by adjusting

[0291] FIG. 5 shows the CH ４ / CO ２ and CO / CO in the synthesis gas 111 ２ The relationship between the reaction temperature T １ The horizontal axis of FIG. ４ / CO ２ in DRM InGas,” that is, CH in the source gas 110 ４ / CO ２ The vertical axis represents "CO / CO ２ in DRM OutGas”, i.e., CO / CO in the synthesis gas 111 ２ represents.

[0292] As shown in FIG. 5, the reaction temperature T １ When determining the CO / CO ratio in the synthesis gas, ２ To adjust to a desired value, the CH ４ / CO ２ The value can be easily calculated.

[0293] Regarding condition (1), CO / CO ２ is greater than 0 and equal to or less than 124, and the lower limit is preferably 0.20 or more. ２ When the CO / CO ratio is equal to or greater than the lower limit, the effects of the present invention are more excellent. The upper limit is preferably 0.50 or less. ２ When it is equal to or less than the upper limit, the effect of the present invention is more excellent.

[0294] In the embodiment of the present invention described with reference to FIGS. 13 to 16, temperature control in the DRM reactor 103 and the solid carbon collector 106 is not essential, but by controlling the temperature, the effects of the present invention can be improved.

[0295] The present invention will be described below with reference to examples, but the present invention is not limited to these. [Example 1]

[0296] [Demonstration test of hydrogen production method] First, referring to Chemical Science, 2019, 10, 3701-3705 (Topologically immobilized catalysis center for long-term stable carbon dioxide reforming of methane), ２ O ３ " was synthesized.

[0297] Next, "Ni#Y ２ O ３ 0.1 g of the powder was filled into a quartz reaction tube with an outer diameter of 3 / 8 inches (approximately 9.53 mm). The powder was sandwiched and fixed between quartz wool. Next, Fe was placed directly below the powder in the same manner. ３ O ４ The powder was filled and fixed. ２ O ３ " Powder, Fe ３ O ４ A PdAg alloy membrane (φ20 mm; thickness 100 μm) was connected in series downstream of the quartz reaction tube in which the powders were sequentially filled.

[0298] The primary side of this membrane was exhausted as bleed gas via a GC (gas chromatograph). The secondary side of this membrane was continuously aspirated by a pump via a mass flow meter. The gas was branched directly above this pump to a Q-Mass (quadrupole mass spectrometer), and the signal with a mass (m / z) of 2 was continuously monitored. The signal intensity of the Q-Mass was calibrated using the indicated value of the mass flow meter.

[0299] 23 is a photograph of the hydrogen production apparatus used in this demonstration experiment. The hydrogen production apparatus in Fig. 23 has a pair of holders 501 for mounting a quartz reaction tube, a heater 502, a sensor 503 for measuring the temperature inside the heater, and a PdAg alloy membrane 504 disposed downstream. The source gas introduced from FL1 flows through FL2 (in the drawing, the quartz reaction tube is not mounted), FL3, FL4, FL5, and FL6 in this order.

[0300] First, N ２ The temperature was raised from room temperature to 400°C while gas was passed through at a rate of 5 ml / min. ４ Gas, CO ２ Each gas was added at 10 ml / min, making the total inflow into the quartz reaction tube 25 ml / min.

[0301] When the temperature of each powder in the quartz reaction tube reached approximately 470°C, hydrogen was detected on the secondary side of the PdAg alloy membrane as the DRM reaction began. The hydrogen flow rate on the secondary side of the PdAg alloy membrane increased with increasing temperature, and the mass flow meter reading reached 3.1 ml / min at a temperature of 700°C. This value then gradually decreased, reaching a steady state of approximately 2.5 ml / min after 15 hours.

[0302] 24 shows the results of the above demonstration test, with the horizontal axis representing the elapsed time, the vertical axis (left) representing the amount of hydrogen produced (ml / min), and the vertical axis (right) representing the total amount of hydrogen produced (L). The above results demonstrate that the hydrogen production method of the present invention can stably produce hydrogen over a long period of time.

[0303] [Example 2] In the configuration of the hydrogen production apparatus shown in Figure 25, the temperature of the DRM reactor 103 was controlled to 700°C, the temperature of the solid carbon collector 106 to 450°C, and the temperature of the hydrogen separator 107 to 350°C. As part of the heat amount given to the DRM reactor 103, methane: 15 Nm3 was burned in the methane combustion furnace 108 outside the hydrogen production apparatus. ３ / h was burned in air, carbon dioxide: 15 Nm ３ The material balance and energy balance in the case where 1 / h of CO₂ was generated were determined by simulation.

[0304] (1) Raw material gas introduced into the DRM reactor 103 from outside the hydrogen production device Methane: 43 Nm ３ / h, carbon dioxide: 15 Nm ３ / h (2) Raw material gas 110 introduced into DRM reactor 103 Methane: 45 Nm ３ / h, carbon dioxide: 130 Nm ３ / h, hydrogen: 20 Nm ３ / h, carbon monoxide: 1Nm ３ / h, water: 0Nm ３ / h (3) Synthesis gas 111 discharged from DRM reactor 103 Methane: 2 Nm ３ / h, carbon dioxide: 59 Nm ３ / h, hydrogen: 82 Nm ３ / h, carbon monoxide: 115 Nm ３ / h, water: 27Nm ３ / h (4) Carbon fixed in the solid carbon collector 106: 31 kg / h (5) Treated gas 112 discharged from the solid carbon collector 106 and introduced into the hydrogen separator 107: Methane: 2 Nm ３ / h, carbon dioxide: 115 Nm ３ / h, hydrogen: 82 Nm ３ / h, carbon monoxide: 1Nm ３ / h, water: 27Nm ３ / h (6) Hydrogen separated and collected in hydrogen separator 107: 62 Nm ３ / h (7) Exhaust gas 114 discharged from hydrogen separator 107 Methane: 2 Nm ３ / h, carbon dioxide: 115 Nm ３ / h, hydrogen: 20 Nm ３ / h, carbon monoxide: 1Nm ３ / h, water: 0Nm ３ / h

[0305] In Example 2, the hydrogen extraction rate (%) can be calculated by calculating the ratio of the flow rate of hydrogen 113 from the hydrogen separator 107 to the flow rate of hydrogen in the treated gas 112 from the solid carbon collector 106. In Example 1, the hydrogen extraction rate was 75%, confirming that hydrogen could be extracted at a high rate.

[0306] [Example 3] In the configuration of the hydrogen production apparatus shown in Figure 26, the temperature of the DRM reactor 103 was controlled to 700°C, the temperature of the solid carbon collector 106 to 450°C, and the temperature of the hydrogen separator 107 to 350°C. As part of the heat amount given to the DRM reactor 103, methane: 15 Nm3 was burned in the methane combustion furnace 108 outside the hydrogen production apparatus. ３ / h was burned in air, carbon dioxide: 15 Nm ３ The material balance and energy balance in the case where 1 / h of CO₂ was generated were determined by simulation.

[0307] (1) Raw material gas introduced into the DRM reactor 103 from outside the hydrogen production device Methane: 43 Nm ３ / h, carbon dioxide: 15 Nm ３ / h (2) Raw material gas 110 introduced into DRM reactor 103 Methane: 45 Nm ３ / h, carbon dioxide: 130 Nm ３ / h, hydrogen: 30 Nm ３ / h, carbon monoxide: 1Nm ３ / h, water: 0Nm ３ / h (3) Synthesis gas 111 discharged from DRM reactor 103 Methane: 2 Nm ３ / h, carbon dioxide: 59 Nm ３ / h, hydrogen: 89 Nm ３ / h, carbon monoxide: 114Nm ３ / h, water: 27Nm ３ / h (4) Carbon fixed in the solid carbon collector 106: 30 kg / h (5) Treated gas 112 discharged from the solid carbon collector 106 and introduced into the hydrogen separator 107: Methane: 2 Nm ３ / h, carbon dioxide: 115 Nm ３ / h, hydrogen: 89 Nm ３ / h, carbon monoxide: 1Nm ３ / h, water: 27Nm ３ / h (6) Hydrogen separated and collected in hydrogen separator 107: 59 Nm ３ / h (7) Exhaust gas 114 discharged from hydrogen separator 107 Methane: 2 Nm ３ / h, carbon dioxide: 115 Nm ３ / h, hydrogen: 30 Nm ３ / h, carbon monoxide: 1Nm３ / h, water: 0Nm ３ / h

[0308] In Example 3, the hydrogen extraction rate (%) can be calculated by calculating the ratio of the flow rate of hydrogen 113 from the hydrogen separator 107 to the flow rate of hydrogen in the treated gas 112 from the solid carbon collector 106. In Example 1, the hydrogen extraction rate was 66%, confirming that hydrogen could be extracted at a high rate.

[0309] Example 4 In the configuration of the hydrogen production apparatus shown in FIG. 27 , the temperature of the DRM reactor 103 was controlled to 700° C., the temperature of the solid carbon collector 106 to 450° C., and the temperature of the hydrogen separator 107 to 350° C., and the hydrogen separated and collected by the hydrogen separator 107 was burned as part of the heat amount provided to the DRM reactor 103. The material balance and energy balance were determined by simulation.

[0310] (1) Raw material gas introduced into the DRM reactor 103 from outside the hydrogen production device Methane: 42 Nm ３ / h, carbon dioxide: 10 Nm ３ / h (2) Raw material gas 110 introduced into DRM reactor 103 Methane: 45 Nm ３ / h, carbon dioxide: 95 Nm ３ / h, hydrogen: 0 Nm ３ / h, carbon monoxide: 1Nm ３ / h, water: 0Nm ３ / h (3) Synthesis gas 111 discharged from DRM reactor 103 Methane: 3 Nm ３ / h, carbon dioxide: 37 Nm ３ / h, hydrogen: 68 Nm ３ / h, carbon monoxide: 101Nm ３ / h, water: 15Nm ３ / h (4) Carbon fixed in the solid carbon collector 106: 27 kg / h (5) Treated gas 112 discharged from the solid carbon collector 106 and introduced into the hydrogen separator 107: Methane: 3 Nm ３ / h, carbon dioxide: 85 Nm ３ / h, hydrogen: 68 Nm ３ / h, carbon monoxide: 1Nm ３ / h, water: 0Nm ３ / h (6) Hydrogen separated and collected in hydrogen separator 107: 68 Nm ３ / h (7) Of the hydrogen separated and collected in the hydrogen separator 107, hydrogen that is combusted and used to supply heat to the DRM reactor 103: 44 Nm ３ / h (8) Exhaust gas 114 discharged from hydrogen separator 107 Methane: 3 Nm ３ / h, carbon dioxide: 85 Nm ３ / h, hydrogen: 0 Nm ３ / h, carbon monoxide: 1Nm ３ / h, water: 0Nm ３ / h

[0311] [Example 5] In the configuration of the hydrogen production apparatus shown in Figure 28, the temperature of the DRM reactor 103 was controlled to 700°C, the temperature of the solid carbon collector 106 to 550°C, and the temperature of the hydrogen separator 107 to 350°C. As part of the heat amount to be given to the DRM reactor 103, heat from the exhaust gas 114 was recovered before the exhaust gas 114 was introduced into the DRM reactor 103, and carbon dioxide: 90 Nm ３ The material balance and energy balance in the case where 1 / h of CO₂ was generated were determined by simulation.

[0312] (1) Raw material gas introduced into the DRM reactor 103 from outside the hydrogen production device Methane: 45 Nm ３ / h (2) Raw material gas 110 introduced into DRM reactor 103 Methane: 45 Nm ３ / h, carbon dioxide: 90 Nm ３ / h, hydrogen: 0 Nm ３ / h, carbon monoxide: 0 Nm ３ / h, water: 0Nm ３ / h (3) Synthesis gas 111 discharged from DRM reactor 103 Methane: 3 Nm ３ / h, carbon dioxide: 34Nm ３ / h, hydrogen: 68 Nm ３ / h, carbon monoxide: 97 Nm ３ / h, water: 15Nm ３ / h (4) Carbon fixed in the solid carbon collector 106: 24 kg / h (5) Treated gas 112 discharged from the solid carbon collector 106 and introduced into the hydrogen separator 107: Methane: 3 Nm ３ / h, carbon dioxide: 79 Nm ３ / h, hydrogen: 68 Nm ３ / h, carbon monoxide: 8 Nm ３ / h, water: 0Nm ３ / h (6) Hydrogen separated and collected in hydrogen separator 107: 43 Nm ３ / h (7) Exhaust gas 114 discharged from hydrogen separator 107 Methane: 3 Nm ３ / h, carbon dioxide: 79 Nm ３ / h, hydrogen: 25 Nm ３ / h, carbon monoxide: 8 Nm ３ / h, water: 0Nm ３ / h (8) Circulation gas 120 circulated to the DRM reactor 103 through the third flow path 115c after heat recovery: methane: 0 Nm ３ / h, carbon dioxide: 90 Nm ３ / h, hydrogen: 0 Nm ３ / h, carbon monoxide: 0 Nm ３ / h, water: 0Nm ３ / h

[0313] 11: Substrate 12: Coating layer 100, 200, 300: Hydrogen production device 101: Dry reforming catalyst (DRM catalyst) 102: First temperature controller 103: Dry reforming (DRM reactor) reactor 104: Solid carbon collection catalyst 105: Second temperature controller 106: Solid carbon collector 106A, 106B, 106C, 106D, 106E: Solid carbon collector 107: Hydrogen separator 108: Methane combustion furnace 108a, 109a: Heat supply flow path 109: Hydrogen combustion furnace 110: Raw material gas 111: Synthesis gas 112: Treated gas 113: Hydrogen 114: Exhaust gas 115: Flow path 115a: First flow path 115b: Second flow path 115c: Third flow path 116: Hydrogen extraction flow path 120: Circulating gas 121: Methane 122: Carbon dioxide 201: Control device 202: Processor 203: Memory 204: Heat recovery device 205: Raw material gas regulator 301: Reactor 302: Third temperature regulator 401: Compressor 402, 404: Pressure regulation valve 403: Gas holder 405A, 405B, 405C, 406A, 406B, 406C: Valves 407: Buffer tank 408: Gas composition regulator HE: Heat exchanger W: Water supply flow path V: Steam

Claims

1. performing a dry reforming reaction in the presence of a dry reforming catalyst to obtain a synthesis gas containing carbon monoxide and hydrogen from a raw material gas containing methane and carbon dioxide; performing a solid carbon capture reaction in which the synthesis gas is reacted in the presence of a solid carbon capture catalyst to produce solid carbon from the carbon monoxide in the synthesis gas, and obtain the solid carbon and a treated gas; Separating the treated gas into an exhaust gas and hydrogen to obtain hydrogen; CO / CO is the molar ratio of the carbon monoxide content to the carbon dioxide content in the synthesis gas. ２ and the reaction temperature T of the dry reforming reaction. １ (°C), and the reaction temperature T of the solid carbon capture reaction ２ (°C) and the following condition (1): [Equation 1] A hydrogen production method that satisfies the above requirements.

2. The reaction temperature T ２ The method for producing hydrogen according to claim 1 , wherein the temperature is equal to or higher than the activation temperature of the solid carbon capture catalyst.

3. CH, which is the molar ratio of the methane content to the carbon dioxide content in the raw material gas ４ / CO ２ The method for producing hydrogen according to claim 1 or 2, wherein is 0.5 or less.

4. The reaction temperature T １ The method for producing hydrogen according to claim 1 or 2, wherein the temperature is equal to or higher than the activation temperature of the dry reforming catalyst.

5. The reaction temperature T １ The method for producing hydrogen according to claim 1 or 2, wherein the temperature is 600°C or higher.

6. 3. The method for producing hydrogen according to claim 1, further comprising recovering heat from the exhaust gas and using the heat in at least one reaction selected from the group consisting of the dry reforming reaction and the solid carbon capture reaction.

7. The method for producing hydrogen according to claim 6 , wherein the recovery is performed by introducing the exhaust gas into a fuel cell.

8. The method for producing hydrogen according to claim 6 , wherein the recovery is performed by combusting the exhaust gas.

9. 3. The method for producing hydrogen according to claim 1, wherein the separation of the treated gas is performed using a hydrogen separation membrane.

10. a dry reforming reactor that performs a dry reforming reaction in the presence of a dry reforming catalyst to obtain a synthesis gas containing carbon monoxide and hydrogen from a raw material gas containing methane and carbon dioxide; a solid carbon collector that performs a solid carbon capture reaction by reacting the synthesis gas in the presence of a solid carbon capture catalyst to produce solid carbon from the carbon monoxide in the synthesis gas and obtain the solid carbon and a treated gas; a hydrogen separator that separates the treated gas into an exhaust gas and hydrogen; The reaction temperature T １ a first temperature controller for adjusting the temperature (°C); The reaction temperature T ２ (°C), and a second temperature controller; a raw material gas regulator that adjusts the composition of the raw material gas; a control device; The control device controls the synthesis gas to calculate a molar ratio of the carbon monoxide content to the carbon dioxide content, CO / CO ２ and the reaction temperature T １ and the reaction temperature T ２ and satisfy the following condition (1): [Equation 2] The hydrogen generating apparatus controls the first temperature regulator, the second temperature regulator, and the raw material gas regulator so as to satisfy the above condition.

11. The control device is configured to calculate a CH ４ / CO ２ The hydrogen production device according to claim 10 , wherein the raw material gas regulator is controlled so that the ratio of the raw material gas pressure to the raw material gas pressure is 0.5 or less.

12. The control device controls the first temperature regulator and the second temperature regulator to adjust the reaction temperature T １ is controlled to a temperature equal to or higher than the activation temperature of the dry reforming catalyst, and the reaction temperature T ２ The hydrogen production device according to claim 10 or 11, wherein the temperature is controlled to be equal to or higher than the activation temperature of the solid carbon capture catalyst.

13. The hydrogen production device according to claim 10 or 11, further comprising a heat recovery unit for recovering heat from the exhaust gas.

14. The hydrogen production device according to claim 13 , wherein the heat is used to heat at least one selected from the group consisting of the dry reforming reactor and the solid carbon collector.

15. The hydrogen production device according to claim 10 or 11, wherein the hydrogen separator includes a hydrogen separation membrane.

16. The hydrogen production device according to claim 13 , wherein the heat recovery device comprises a fuel cell.

17. a dry reforming reaction step of obtaining a synthesis gas containing carbon monoxide and hydrogen from a raw material gas containing methane and carbon dioxide in the presence of a dry reforming catalyst; a solid carbon collection step in which the synthesis gas from the dry reforming reaction step is introduced and solid carbon is produced from carbon monoxide in the synthesis gas in the presence of a solid carbon collection catalyst to obtain a treated gas; a hydrogen separation step of extracting hydrogen from the treated gas from the solid carbon capture step to obtain an exhaust gas comprising carbon dioxide; A hydrogen production method, characterized in that the exhaust gas from the hydrogen separation step is introduced into the dry reforming reaction step, and carbon dioxide is circulated without being discharged to the outside.

18. 18. The method for producing hydrogen according to claim 17, wherein methane is combusted to generate heat and carbon dioxide, the generated heat is introduced into the dry reforming reaction step, the feed gas containing carbon dioxide in an amount equivalent to the generated carbon dioxide is introduced into the dry reforming reaction step, and carbon in an amount equivalent to carbon contained in the carbon dioxide and methane in the feed gas is collected as solid carbon in the solid carbon collection step.

19. 18. The method for producing hydrogen according to claim 17, further comprising taking out and combusting a portion of the hydrogen separated in the hydrogen separation step, and supplying the generated heat to the dry reforming reaction step.

20. 18. The method for producing hydrogen according to claim 17, wherein heat is recovered from the exhaust gas from the hydrogen separation step and supplied to the dry reforming reaction step before the exhaust gas is introduced into the dry reforming reaction step.

21. a dry reforming reactor for obtaining a synthesis gas containing carbon monoxide and hydrogen from a feed gas containing methane and carbon dioxide in the presence of a dry reforming catalyst; a solid carbon collector into which the synthesis gas from the dry reforming reactor is introduced, and which produces solid carbon from carbon monoxide in the synthesis gas in the presence of a solid carbon capture catalyst to obtain a treated gas; a hydrogen separator that extracts hydrogen from the treated gas from the solid carbon collector to obtain an exhaust gas that includes carbon dioxide; a first flow path that supplies synthesis gas from the dry reforming reactor to the solid carbon collector; A hydrogen production device comprising: a second flow path that supplies treated gas from the solid carbon collector to the hydrogen separator; and a third flow path that supplies exhaust gas from the hydrogen separator to the dry reforming reactor, wherein carbon dioxide is circulated internally without being discharged to the outside.

22. 22. The hydrogen production device according to claim 21, further comprising: a methane combustion furnace; and a heat supply passage that supplies heat from the methane combustion furnace to the dry reforming reactor.

23. 22. The hydrogen production device according to claim 21, further comprising: a hydrogen extraction passage that extracts a portion of hydrogen from the hydrogen separator; a hydrogen combustion furnace that combusts the extracted hydrogen; and a heat supply passage that supplies heat from the hydrogen combustion furnace to the dry reforming reactor.

24. 22. The hydrogen production device according to claim 21, wherein a heat recovery unit that recovers heat from the exhaust gas is connected to the third flow path, and the heat recovered by the heat recovery unit is supplied to the dry reforming reactor.

25. The hydrogen production device according to claim 21, further comprising a compressor in the first flow path.

26. 26. The hydrogen production device according to claim 25, further comprising a heat exchanger that converts heat generated in the solid carbon collector into steam and supplies the steam to the compressor.

27. 26. The hydrogen production apparatus according to claim 25, wherein a pressure regulating valve is provided at an inlet of the hydrogen separator, and a gas holder and a pressure regulating valve are provided at an outlet of the hydrogen separator.

28. The hydrogen production device according to claim 21, further comprising a water supply passage for supplying water generated in the dry reforming reactor to the solid carbon collector.

29. 29. The hydrogen production device according to claim 28, further comprising a compressor in the first flow path, and further comprising a steam supply passage that supplies steam generated in the solid carbon collector to the compressor.

30. 22. The hydrogen production device according to claim 21, further comprising a compressor in the first flow path, the first flow path being branched downstream of the compressor to arrange a plurality of the solid carbon collectors in parallel, and valves being provided at the inlet and outlet of each solid carbon collector.

31. The hydrogen production device according to claim 30, further comprising a buffer tank provided in the first flow path downstream of the compressor and upstream of the branch.

32. 22. The hydrogen production device according to claim 21, further comprising a compressor in the first flow path, a plurality of the solid carbon collectors arranged in series, and a gas composition adjusting unit provided between each solid carbon collector.

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