Method for producing hydrogen generator, method for operating hydrogen generator, and hydrogen generator

Abstract

This method for producing a hydrogen generator comprises: assembling a hydrogen generator 100 so as to include a reforming part 122 which contains a catalyst precursor enclosed therein; introducing a reducing gas into a reaction vessel 133 to reduce some of the catalyst precursor; and stopping the introduction of the reducing gas into the reaction vessel 133 in a state where the catalyst precursor coexists with the catalyst.

Description

Method for manufacturing hydrogen generation device, method for operating hydrogen generation device, and hydrogen generation device

[0001] The present disclosure relates to a method for manufacturing a hydrogen generation device, a method for operating a hydrogen generation device, and a hydrogen generation device.

[0002] Patent Document 1 describes a method for reducing catalysts installed in reformers and CO converters of fuel cell power generation systems. The oxidized catalyst is reduced by reducing gas supplied from a reducing gas generator such as a hydrogen cylinder.

[0003] Japanese Patent Application Publication No. 6-349509

[0004] Conventional methods have had problems such as the long time required to reduce all of the oxidized catalyst and the high cost of reducing gases such as hydrogen gas.

[0005] The present disclosure provides techniques for reducing the amount of time spent reducing catalyst precursors and the amount of reducing gas used.

[0006] The present disclosure provides a method for manufacturing a hydrogen generation device, the hydrogen generation device comprising a reaction vessel and a reforming section located inside the reaction vessel, the method including: assembling the hydrogen generation device so that a catalyst precursor is enclosed in the reforming section; introducing a reducing gas into the reaction vessel to reduce a portion of the catalyst precursor; and stopping the introduction of the reducing gas into the reaction vessel in a state where the catalyst precursor and the catalyst are mixed together.

[0007] In another aspect, the present disclosure provides a method for operating a hydrogen generation apparatus, wherein the hydrogen generation apparatus is manufactured by the manufacturing method of the present disclosure and comprises: the reaction vessel; the reforming section; a heating section disposed inside the reaction vessel; and an evaporation section that heats water and a raw material gas with heat from the heating section, the operation method including supplying the water and the raw material gas to the evaporation section, wherein the hydrogen-containing gas is generated by supplying water vapor and the raw material gas from the evaporation section to the reforming section, and the generated hydrogen-containing gas reduces a precursor of the catalyst remaining in the reforming section.

[0008] The techniques of the present disclosure can reduce the time spent reducing catalyst precursors and the amount of reducing gas used.

[0009] 2. A flowchart showing a method for producing a hydrogen generator according to the first embodiment. A configuration diagram of equipment for carrying out the reduction step shown in step S2 of FIG. 2. A graph showing the supply amount of hydrogen gas as a reducing gas, the reduction rate of the catalyst, and the passage of time. A flowchart showing a method for producing a hydrogen generator according to the second embodiment. A configuration diagram of equipment for carrying out the reduction steps shown in steps ST2 and ST3 of FIG. 5. A graph showing the supply amount of hydrogen gas as a reducing gas, the reduction rate of the catalyst, and the passage of time. A configuration diagram of a fuel cell system equipped with a hydrogen generator.

[0010] (Knowledge, etc., that forms the basis of the present disclosure) When a hydrogen generator is manufactured in a factory, a catalyst precursor is sealed in a predetermined position in a reaction vessel. The catalyst precursor is typically an oxide of the catalyst. For example, when the catalyst is Ni, NiO is sealed in the reaction vessel. Thereafter, a process for reducing the catalyst precursor is performed, thereby completing the hydrogen generator as a product. In this way, it is not necessary to provide a special atmosphere, such as a nitrogen atmosphere, in the factory, and it is also possible to reduce material costs. For example, the price of NiO is cheaper than the price of pure Ni.

[0011] The present inventors have conducted extensive research into technologies for reducing the time spent on reduction processes in factories and the amount of reducing gas used. As a result, they have discovered that even when a catalyst and a catalyst precursor are mixed, hydrogen gas can be generated by the action of the catalyst, and the generated hydrogen can be used to reduce the catalyst precursor. Based on this finding, the present inventors have completed the technology of the present disclosure.

[0012] Hereinafter, embodiments will be described in detail with reference to the drawings. However, unnecessary detailed description may be omitted. For example, detailed description of already well-known matters or redundant description of substantially the same configuration may be omitted.

[0013] The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims.

[0014] First Embodiment Hereinafter, a first embodiment will be described with reference to FIGS. 1 to 4. FIG.

[0015] [1-1. Configuration] Fig. 1 is a cross-sectional view of an example of a hydrogen generation device to be produced by the method of embodiment 1. The hydrogen generation device 100 includes a heating section 120, an evaporating section 121, and a reforming section 122. The hydrogen generation device 100 is a device that generates a hydrogen-containing gas from a raw material gas by a steam reforming reaction. The raw material gas is typically a hydrocarbon gas such as methane gas. The generated hydrogen-containing gas is supplied to, for example, a fuel cell.

[0016] An example of the heating unit 120 is a burner that burns combustible gas. The burner burns fuel gas to increase the temperature inside the hydrogen generation apparatus 100. A combustion tube 130 and a heating unit partition wall 131 are provided around the heating unit 120. The combustion tube 130 surrounds the heating unit 120. The heating unit partition wall 131 surrounds the combustion tube 130. A combustion exhaust gas flow path 140 is formed between the combustion tube 130 and the heating unit partition wall 131. An outlet pipe 155 is attached to the top of the heating unit partition wall 131. The combustion exhaust gas is discharged to the outside of the hydrogen generation apparatus 100 through the combustion exhaust gas flow path 140 and the outlet pipe 155.

[0017] The hydrogen generator 100 further includes an inner cylinder 132 and a reaction vessel 133. The inner cylinder 132 surrounds the heating unit partition wall 131. A supply pipe 145 is connected to the inner cylinder 132. A raw material gas and water are supplied to the evaporation unit 121 through the supply pipe 145.

[0018] A rod-shaped body 135 is disposed between the inner cylinder 132 and the heating unit partition wall 131. This forms a spiral flow path as the evaporation unit 121. In the evaporation unit 121, water is heated to generate steam.

[0019] The reforming section 122 is provided downstream of the evaporating section 121, between the heating section partition wall 131 and the inner cylinder 132. The reforming section 122 includes a catalyst. A hydrogen-containing gas is produced from the raw material gas and steam by a steam reforming reaction in the reforming section 122.

[0020] The reaction vessel 133 has a cylindrical shape with a bottom. The reaction vessel 133 accommodates the heating section 120, the evaporation section 121, and the reforming section 122. A return flow path 141 is formed between the reaction vessel 133 and the inner cylinder 132. The return flow path 141 guides the hydrogen-containing gas that has flowed downward from the reforming section 122 upward.

[0021] The hydrogen generation apparatus 100 may or may not include a CO reduction unit 123 and a CO removal unit 124. The CO reduction unit 123 reduces the concentration of carbon monoxide contained in the hydrogen-containing gas through a shift reaction. The CO removal unit 124 removes carbon monoxide contained in the hydrogen-containing gas through a selective oxidation reaction. The hydrogen-containing gas is discharged to the outside of the hydrogen generation apparatus 100 through an outlet pipe 154.

[0022] [1-2. Operation] FIG. 2 is a flowchart showing a method for manufacturing the hydrogen generation apparatus according to the first embodiment.

[0023] In step S1, the hydrogen generator 100 is assembled. Specifically, the hydrogen generator 100 is assembled so that a catalyst precursor is sealed in the reforming section 122. The catalyst is a catalyst for causing a steam reforming reaction, and is, for example, Ni. The catalyst precursor is an oxide of the catalyst, and is, for example, NiO. According to the method of this embodiment, a special atmosphere such as a nitrogen atmosphere is not required when assembling the hydrogen generator 100. Furthermore, oxides such as NiO are cheaper than pure Ni, which can be used immediately as a catalyst.

[0024] Next, in step S2, a portion of the catalyst precursor is reduced. Specifically, a reducing gas is introduced into the reaction vessel 133 to reduce a portion of the catalyst precursor. Thereafter, the introduction of the reducing gas into the reaction vessel 133 is stopped while the catalyst precursor and the catalyst are mixed together. The reducing gas is, for example, hydrogen gas, typically pure hydrogen gas with a purity of 99% or more. The reducing gas is introduced into the reaction vessel 133 through the supply pipe 145 shown in FIG. 1 and reaches the reforming section 122 via the evaporation section 121. In the reforming section 122, the reducing gas comes into contact with the catalyst precursor. This reduces the catalyst precursor. When the catalyst precursor is NiO, the reaction represented by the following formula (1) occurs. To speed up the reduction reaction, the reducing gas and catalyst precursor may be heated using the heating section 120. The remaining reducing gas and water vapor are then discharged to the outside of the hydrogen generator 100 through the outlet pipe 154.

[0025] NiO2+2H2→Ni+2H2O...(1)

[0026] The timing for stopping the introduction of the reducing gas can be experimentally determined in advance. For example, the reduction process of step S2 is terminated when the supply amount of the reducing gas reaches a predetermined amount. The supply amount of the reducing gas is measured with a flow meter, and the introduction of the reducing gas is stopped when the measured value reaches the predetermined amount. Alternatively, the introduction of the reducing gas may be stopped when a predetermined time has elapsed since the start of the supply of the reducing gas.

[0027] The hydrogen generator 100 is provided to a customer and installed at a predetermined location with the catalyst precursor remaining in the reforming section 122. Even if the catalyst and the catalyst precursor are mixed, hydrogen gas can be generated by the action of the catalyst, and the catalyst precursor can be reduced by the generated hydrogen gas. Therefore, according to this embodiment, it is possible to shorten the time spent in the reduction step of step S2 in a factory and reduce the amount of reducing gas used.

[0028] 3 is a configuration diagram of equipment for performing the reduction process of step S2 in FIG. 2. The equipment 200 includes a reducing gas supply unit 201, a fuel supply unit 180, an air supply unit 181, and a control unit 210. The reducing gas supply unit 201 is connected to the evaporation unit 121 of the hydrogen generator 100 through a flow path 207. The reducing gas supply unit 201 is, for example, a hydrogen gas cylinder. A flow rate adjustment valve 203 is provided in the flow path 207. The control unit 210 controls the flow rate adjustment valve 203 to adjust the flow rate of the reducing gas. By setting the aperture of the flow rate adjustment valve 203 to zero at an appropriate timing, the supply of reducing gas is stopped, and the reduction process of step S2 can be completed.

[0029] The fuel supply unit 180 and the air supply unit 181 are connected to the heating unit 120 of the hydrogen generator 100 via a flow path 184 and a flow path 185, respectively. The fuel supply unit 180 is, for example, a gas cylinder or a city gas infrastructure. The air supply unit 181 is, for example, a blower. The flow path 184 and the flow path 185 are provided with flow rate control valves 182 and 183, respectively. The control unit 210 controls the flow rate control valves 182 and 183 to adjust the flow rate of the fuel and the flow rate of the air. This makes it possible to adjust the temperature of the reducing gas and the temperature of the reforming unit 122 to temperatures suitable for reducing the catalyst precursor.

[0030] FIG. 4 is a graph showing the supply amount or flow rate of hydrogen gas as a reducing gas, the catalyst reduction rate, and the passage of time. The left vertical axis represents the supply amount or flow rate of hydrogen gas. The right vertical axis represents the catalyst reduction rate. The horizontal axis represents the passage of time (i.e., time). In the reduction process of step S2 in FIG. 2, for example, hydrogen gas is introduced into the reaction vessel 133 of the hydrogen generation device 100 at a constant flow rate (unit: liters / min). As a result, the reduction rate increases. The reduction rate represents the ratio of the amount of reduced catalyst material to the total amount of catalyst precursor and reduced catalyst material. The amount of hydrogen gas (unit: liters) required to reduce the entire amount of catalyst precursor is represented by "L1" on the left vertical axis of the graph.

[0031] At time Tb, the introduction of hydrogen gas is stopped. The hydrogen generation device 100 is shipped as a commercial product. The reduction rate R1 at time Tb is less than 100%. The amount of hydrogen gas used in the reduction step is represented by "L2" on the left vertical axis of the graph. L2 is a value smaller than L1.

[0032] The hydrogen generator 100 is delivered to a customer and used as a product. Operation after time Tb can be the operating process of the hydrogen generator 100 at the customer's site. In the operating process, water and raw material gas are supplied to the evaporation section 121 of the hydrogen generator 100. When the supply of water and raw material gas begins, water vapor and raw material gas are supplied from the evaporation section 121 to the reforming section 122 almost simultaneously. As a result, a hydrogen-containing gas is generated in the reforming section 122, and the catalyst precursor remaining in the reforming section 122 is reduced by the generated hydrogen-containing gas. As a result, the hydrogen generator 100 can fully demonstrate its designed performance.

[0033] During the period from time Tb to time Tc1, the amount of hydrogen gas generated in the reforming section 122 gradually increases. At time Tc1, the reduction rate reaches 100%, and thereafter the amount of hydrogen gas generated in the reforming section 122 is maintained at a constant amount. Time Tc1 is the point at which the total amount of hydrogen reaches the required amount of hydrogen gas, L1. The total amount of hydrogen is the sum of the amount of hydrogen gas supplied from the outside and the amount of hydrogen gas generated in the reforming section 122.

[0034] According to this embodiment, after stopping the introduction of the reducing gas into the reaction vessel 133, water and the raw material gas are supplied to the evaporation section 121. As described above, supplying water and the raw material gas to the evaporation section 121 corresponds to normal operation of the hydrogen generation apparatus 100. Therefore, the method of this embodiment does not cause any disadvantage to the customer.

[0035] Second Embodiment Hereinafter, a second embodiment will be described with reference to FIGS.

[0036] 5 is a flowchart showing a method for producing a hydrogen generation apparatus according to embodiment 2. Steps ST1 and ST2 correspond to steps S1 and S2 described with reference to FIG.

[0037] In step ST3, water and raw material gas are supplied to the evaporator 121 together with the reducing gas. In the evaporator 121, the water is heated to generate steam. The steam and raw material gas are supplied to the reformer 122. Since the reformer 122 contains a catalyst and a catalyst precursor, a steam reforming reaction occurs and a hydrogen-containing gas is generated. The catalyst precursor remaining in the reformer 122 is quickly reduced by the actions of both the reducing gas supplied from the outside and the generated hydrogen-containing gas.

[0038] The process of step ST3 does not need to be performed until all of the catalyst precursor is reduced, and may be completed in a state where the catalyst precursor and the catalyst are mixed together, as in the first embodiment.

[0039] FIG. 6 is a configuration diagram of equipment for performing the reduction process shown in steps ST2 and ST3 in FIG. 5 . The equipment 220 further includes a water supply unit 202 and a raw material gas supply unit 300 in addition to the equipment 200 described with reference to FIG. 3 . The water supply unit 202 is connected to the evaporator 121 of the hydrogen generator 100 through a flow path 208. The water supply unit 202 is, for example, a water tank. The flow path 208 is provided with a flow rate control valve 204. The raw material gas supply unit 300 is connected to the evaporator 121 of the hydrogen generator 100 through a flow path 302. The raw material gas supply unit 300 is, for example, a gas cylinder or a city gas infrastructure. The flow path 302 is provided with a flow rate control valve 301. The control unit 210 controls the flow rate control valves 204 and 301 to adjust the flow rates of the water and the raw material gas.

[0040] 7 is a graph showing the supply amount of hydrogen gas as reducing gas, the reduction rate of the catalyst, and the passage of time. In this embodiment, step ST2 shown in FIG. 5 is performed during the period from time zero to time Td. Step ST3 shown in FIG. 5 is performed during the period from time Td to time Tb. During the period from time Td to time Tb, the slopes of the graph showing the reduction rate and the graph showing the total hydrogen amount are steeper than those during the period from time zero to time Tb. The period from time Td to time Tb can be considered a period during which the hydrogen generator 100 is in operation, since a steam reforming reaction occurs in the reforming section 122.

[0041] According to this embodiment, the period during which hydrogen gas is introduced into the reaction vessel 133 partially overlaps with the period during which water and the source gas are supplied to the evaporation section 121. With this configuration, the time required for the reduction step can be further shortened, and the amount of hydrogen gas used can be reduced.

[0042] At time Tb, the introduction of hydrogen gas, water, and raw material gas is stopped. The hydrogen generation device 100 is shipped as a commercial product.

[0043] The hydrogen generator 100 is delivered to a customer and used as a product. Operation after time Tb can be the operating process of the hydrogen generator 100 at the customer's site. In the operating process, water and raw material gas are supplied to the evaporation section 121 of the hydrogen generator 100. When the supply of water and raw material gas begins, water vapor and raw material gas are supplied from the evaporation section 121 to the reforming section 122 almost simultaneously. As a result, a hydrogen-containing gas is generated in the reforming section 122, and the catalyst precursor remaining in the reforming section 122 is reduced by the generated hydrogen-containing gas. As a result, the hydrogen generator 100 can fully demonstrate its designed performance.

[0044] According to this embodiment, since step ST3 shown in Fig. 5 is performed during the period from time Td to time Tb, the payout rate can be quickly increased to 100%. That is, time Tc2 shown in Fig. 7 can be earlier than time Tc1 shown in Fig. 4.

[0045] 4, the water flow rate and the raw material gas flow rate are constant during the operating process. These correspond to, for example, the water flow rate and the raw material gas flow rate when a fuel cell system equipped with the hydrogen generator 100 is operating at rated speed. However, in order to quickly reduce the catalyst precursor remaining in the reforming section 122, the water flow rate and the raw material gas flow rate may be intentionally increased during the period from time Tb to time Tc1. In other words, a special operation may be performed only during the first operation after the hydrogen generator 100 is delivered to a customer and a water supply source and a raw material gas supply source are connected to the hydrogen generator 100.

[0046] For example, the water flow rate (unit: liters / min) during the period from the start of supplying water and raw material gas to the evaporation section 121 until a predetermined time has elapsed may be greater than the water flow rate after the end of that period. Immediately after the start of the operating process, the reduction of the catalyst precursor may be insufficient, and the reduction rate may be low. Therefore, by increasing the water flow rate from normal, the reaction equilibrium is shifted, and the amount of hydrogen gas produced during that period can be increased. Despite the period during which the reduction rate is low immediately after the start of operation, the amount of hydrogen gas can be maintained at the same level as normal, so the catalyst precursor can be quickly reduced without reducing the amount of hydrogen gas produced.

[0047] FIG. 8 is a configuration diagram of a fuel cell system including a hydrogen generator 100. The fuel cell system 500 includes the hydrogen generator 100, a fuel cell 400, and a control unit 402. The hydrogen-containing gas generated by the hydrogen generator 100 is supplied to the fuel cell 400. The fuel cell 400 generates electric power using the hydrogen-containing gas. The control unit 402 controls auxiliary devices such as a blower 405, a flow rate control valve 406, and a flow rate control valve 407. The blower 405 is an auxiliary device that supplies air as an oxidant gas to the fuel cell 400. The flow rate of air can be adjusted by controlling the blower 405. The flow rate control valve 406 is an auxiliary device that adjusts the flow rate of water supplied to the hydrogen generator 100. The flow rate control valve 407 is an auxiliary device that adjusts the flow rate of raw material gas supplied to the hydrogen generator 100.

[0048] The control unit 402 controls the flow rate control valve 406 to increase the water flow rate for a predetermined time period during the initial operation after connecting the water supply source and the raw material gas supply source to the hydrogen generator 100 of the fuel cell system 500. The predetermined time period is a time period during which the catalyst precursor is predicted to be sufficiently reduced, and may be a time period determined by a control program executed by the control unit 402. After the predetermined time period has elapsed, the water flow rate is reduced. The operation after the predetermined time period may be the rated operation of the fuel cell system 500.

[0049] The water supply source is, for example, a water tank or a city water infrastructure, and the raw gas supply source is, for example, a gas cylinder or a city gas infrastructure.

[0050] Furthermore, the S / C ratio (steam carbon ratio) during the period from the start of supplying water and raw material gas to the evaporation section 121 until a predetermined time has elapsed may be greater than the S / C ratio after the end of that period. By increasing the S / C ratio from normal, the reaction equilibrium is shifted, and the amount of hydrogen gas produced during that period can be increased. Even during the period in which the reduction rate is low immediately after the start of operation, the amount of hydrogen gas can be maintained at the same level as normal, allowing the catalyst precursor to be quickly reduced without reducing the amount of hydrogen gas produced. The S / C ratio can be controlled by adjusting the flow rate of the raw material gas and the flow rate of water by controlling the flow control valves 406 and 407.

[0051] Furthermore, the flow rate of the raw material gas (unit: liters / min) during the period from the start of supplying water and raw material gas to the evaporation section 121 until a predetermined time has elapsed may be greater than the flow rate of the raw material gas after the end of that period. By increasing the flow rate of the raw material gas, the reaction equilibrium is shifted, and the amount of hydrogen gas produced during that period can be increased. Even during the period when the reduction rate is low immediately after the start of operation, the amount of hydrogen gas can be ensured to be equivalent to that during normal times, so the catalyst precursor can be quickly reduced without reducing the amount of hydrogen gas produced.

[0052] Furthermore, the temperature of the reforming section 122 during the period from the start of supplying water and raw material gas to the evaporating section 121 until a predetermined time has elapsed may be higher than the temperature of the reforming section 122 after the end of that period. By increasing the temperature of the reforming section 122, the reaction rate of the steam reforming reaction can be increased, and the amount of hydrogen gas produced during that period can be increased. Even during the period when the reduction rate is low immediately after the start of operation, the amount of hydrogen gas can be ensured to be equivalent to that during normal times, so the catalyst precursor can be quickly reduced without reducing the amount of hydrogen gas produced.

[0053] The temperature of the reforming section 122 increases by increasing the amount of fuel gas supplied to the heating section 120 of the hydrogen generator 100. The fuel gas consumed in the heating section 120 may be the anode off-gas of the fuel cell 400. Increasing the flow rate of the raw material gas increases the amount of hydrocarbon gas contained in the anode off-gas, so that more fuel gas can be supplied to the heating section 120. As a result, the temperature of the reforming section 122 can be increased.

[0054] The reduction of the catalyst precursor can be promoted by increasing at least one selected from the group consisting of (a) the water flow rate, (b) the S / C ratio, (c) the flow rate of the raw material gas, and (d) the temperature of the reforming section 122.

[0055] [3. Supplementary Notes] The above description of the embodiments discloses the following techniques.

[0056] (Technology 1) A method for manufacturing a hydrogen generation device, the hydrogen generation device comprising a reaction vessel and a reforming section located inside the reaction vessel, the method including: assembling the hydrogen generation device so that a catalyst precursor is enclosed in the reforming section; introducing a reducing gas into the reaction vessel to reduce a portion of the catalyst precursor; and stopping the introduction of the reducing gas into the reaction vessel in a state where the catalyst precursor and the catalyst are mixed together.

[0057] According to the manufacturing method of the present disclosure, the time spent reducing the catalyst precursor and the amount of reducing gas used can be reduced.

[0058] (Technology 2) The method for producing a hydrogen generation device according to Technology 1, wherein the hydrogen generation device further includes a heating unit disposed inside the reaction vessel and an evaporation unit that heats water and a raw material gas with heat from the heating unit, the reforming unit is configured to generate a hydrogen-containing gas by reacting water vapor from the evaporation unit with the raw material gas, and the production method further includes supplying the water and the raw material gas to the evaporation unit, the hydrogen-containing gas is generated by supplying the water vapor and the raw material gas from the evaporation unit to the reforming unit, and the generated hydrogen-containing gas reduces a precursor of the catalyst remaining in the reforming unit. With such a configuration, the hydrogen generation device can fully exhibit its designed performance.

[0059] (Technology 3) The method for manufacturing a hydrogen generator according to Technology 2, wherein the water and the raw material gas are supplied to the evaporator after stopping the introduction of the reducing gas into the reaction vessel. Supplying water and the raw material gas to the evaporator corresponds to normal operation of the hydrogen generator. Therefore, the method of the present disclosure does not cause any disadvantage to customers.

[0060] (Technology 4) The method for manufacturing a hydrogen generator according to Technology 2, wherein a period during which the reducing gas is introduced into the reaction vessel and a period during which the water and the raw material gas are supplied to the evaporator partially overlap. With this configuration, the time required for the reduction step can be further shortened, and the amount of reducing gas used can be reduced.

[0061] (Technology 5) A method for operating a hydrogen generation apparatus, wherein the hydrogen generation apparatus is manufactured by the manufacturing method described in Technology 1 and comprises the reaction vessel, the reforming section, a heating section disposed inside the reaction vessel, and an evaporation section that heats water and a raw material gas with heat from the heating section, the operation method including supplying the water and the raw material gas to the evaporation section, wherein the hydrogen-containing gas is generated by supplying water vapor and the raw material gas from the evaporation section to the reforming section, and the generated hydrogen-containing gas reduces a precursor of the catalyst remaining in the reforming section.

[0062] According to the operating method of the present disclosure, the time spent on reducing the catalyst precursor and the amount of reduction gas used can be reduced, and the hydrogen generator can fully achieve its designed performance.

[0063] (Technology 6) The method for operating a hydrogen generation apparatus according to Technology 5, wherein the flow rate of the water during a period from when the supply of the water and the raw material gas to the evaporation section starts until a predetermined time has elapsed is greater than the flow rate of the water after the period has ended.

[0064] (Technology 7) The method for operating a hydrogen generation apparatus according to Technology 5 or 6, wherein the S / C ratio during a period from when the supply of the water and the raw material gas to the evaporation section starts until a predetermined time has elapsed is greater than the S / C ratio after the end of the period.

[0065] (Technology 8) The method for operating a hydrogen generator according to any one of Techniques 5 to 7, wherein a flow rate of the raw material gas during a period from when the supply of the water and the raw material gas to the evaporation section starts until a predetermined time has elapsed is greater than a flow rate of the raw material gas after the period has ended.

[0066] (Technology 9) The method for operating a hydrogen generation apparatus according to any one of Techniques 5 to 8, wherein the temperature of the reforming section during a period from when the supply of the water and the raw material gas to the evaporation section starts until a predetermined time has elapsed is higher than the temperature of the reforming section after the period has ended.

[0067] According to Techniques 6 to 9, even during the period when the reduction rate is low immediately after the start of operation, the amount of hydrogen gas can be secured to be equivalent to that during normal operation, and therefore the catalyst precursor can be quickly reduced without reducing the amount of hydrogen gas produced.

[0068] (Technology 10) A hydrogen generation apparatus comprising: a reaction vessel; a heating unit disposed inside the reaction vessel; an evaporation unit that heats water and a raw material gas with heat from the heating unit; and a reforming unit that contains a mixture of a catalyst and a precursor of the catalyst and reacts the water vapor from the evaporation unit with the raw material gas to generate a hydrogen-containing gas, wherein, in an initial operation after a water supply source and a raw material gas supply source are connected to the hydrogen generation apparatus, an operation that satisfies at least one selected from the group consisting of the following conditions (a), (b), (c), and (d) is performed to promote reduction of the catalyst precursor: (a) the flow rate of the water during a period from the start of supplying the water and the raw material gas to the evaporation unit until a predetermined time has elapsed is greater than the flow rate of the water after the end of the period; (b) the S / C ratio during a period from the start of supplying the water and the raw material gas to the evaporation unit until a predetermined time has elapsed is greater than the S / C ratio after the end of the period; (c) the flow rate of the raw material gas during a period from when the supply of the water and the raw material gas to the evaporation unit begins until a predetermined time has elapsed is greater than the flow rate of the raw material gas after the period has elapsed; (d) the temperature of the reforming unit during a period from when the supply of the water and the raw material gas to the evaporation unit begins until a predetermined time has elapsed is greater than the temperature of the reforming unit after the period has elapsed.

[0069] According to the hydrogen generation device of the present disclosure, the time spent to reduce the catalyst precursor and the amount of reduction gas used can be reduced.

[0070] The technology of the present disclosure is useful for hydrogen generation devices applied to fuel cell systems and the like.

Claims

1. A method for manufacturing a hydrogen generation device, the hydrogen generation device comprising a reaction vessel and a reforming section located inside the reaction vessel, the method including: assembling the hydrogen generation device so that a catalyst precursor is enclosed in the reforming section; introducing a reducing gas into the reaction vessel to reduce a portion of the catalyst precursor; and stopping the introduction of the reducing gas into the reaction vessel in a state where the catalyst precursor and the catalyst are mixed together.

2. The method for producing a hydrogen generation apparatus according to claim 1, wherein the hydrogen generation apparatus further comprises a heating unit disposed inside the reaction vessel and an evaporation unit that heats water and raw material gas with heat from the heating unit, the reforming unit is configured to generate a hydrogen-containing gas by reacting water vapor from the evaporation unit with the raw material gas, and the production method further comprises supplying the water and the raw material gas to the evaporation unit, the hydrogen-containing gas is generated by supplying the water vapor and the raw material gas from the evaporation unit to the reforming unit, and the generated hydrogen-containing gas reduces a precursor of the catalyst remaining in the reforming unit.

3. The method for producing a hydrogen generator according to claim 2, wherein the water and the raw material gas are supplied to the evaporator after stopping the introduction of the reducing gas into the reaction vessel.

4. The method for producing a hydrogen generator according to claim 2, wherein a period during which the reducing gas is introduced into the reaction vessel and a period during which the water and the raw material gas are supplied to the evaporation section partially overlap.

5. A method for operating a hydrogen generation apparatus, wherein the hydrogen generation apparatus is manufactured by the manufacturing method described in claim 1 and comprises the reaction vessel, the reforming section, a heating section disposed inside the reaction vessel, and an evaporation section that heats water and a raw material gas with heat from the heating section, the operation method including supplying the water and the raw material gas to the evaporation section, wherein the hydrogen-containing gas is generated by supplying water vapor and the raw material gas from the evaporation section to the reforming section, and the generated hydrogen-containing gas reduces a precursor of the catalyst remaining in the reforming section.

6. The method for operating a hydrogen generation apparatus according to claim 5, wherein the flow rate of the water during a period from when the supply of the water and the raw material gas to the evaporation section starts until a predetermined time has elapsed is greater than the flow rate of the water after the end of the period.

7. The method for operating a hydrogen generation apparatus according to claim 5, wherein the S / C ratio during a period from when the supply of the water and the raw material gas to the evaporation section starts until a predetermined time has elapsed is greater than the S / C ratio after the end of the period.

8. The method for operating a hydrogen generation apparatus according to claim 5, wherein the flow rate of the raw material gas during a period from when the supply of the water and the raw material gas to the evaporation section starts until a predetermined time has elapsed is greater than the flow rate of the raw material gas after the end of the period.

9. The method for operating a hydrogen generation apparatus according to claim 5, wherein the temperature of the reforming section during a period from when the supply of the water and the raw material gas to the evaporation section starts until a predetermined time has elapsed is higher than the temperature of the reforming section after the end of the period.

10. A hydrogen generation apparatus comprising: a reaction vessel; a heating unit disposed inside the reaction vessel; an evaporation unit that heats water and a raw material gas with heat from the heating unit; and a reforming unit that contains a mixture of a catalyst and a precursor of the catalyst and reacts the water vapor from the evaporation unit with the raw material gas to generate a hydrogen-containing gas, wherein, in an initial operation after a water supply source and a raw material gas supply source are connected to the hydrogen generation apparatus, the operation satisfies at least one selected from the group consisting of the following conditions (a), (b), (c), and (d), and reduction of the catalyst precursor is promoted: (a) the flow rate of the water during a period from the start of supplying the water and the raw material gas to the evaporation unit until a predetermined time has elapsed is greater than the flow rate of the water after the end of the period; (b) the S / C ratio during the period from the start of supplying the water and the raw material gas to the evaporation unit until a predetermined time has elapsed is greater than the S / C ratio after the end of the period; (c) the flow rate of the raw material gas during a period from when the supply of the water and the raw material gas to the evaporation unit begins until a predetermined time has elapsed is greater than the flow rate of the raw material gas after the period has elapsed; (d) the temperature of the reforming unit during a period from when the supply of the water and the raw material gas to the evaporation unit begins until a predetermined time has elapsed is greater than the temperature of the reforming unit after the period has elapsed.

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