JP2008019121A - Hydrogen production device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen production device provided with a CO converter where the temperature in the converter can be stably held to a suitable temperature range even upon low load driving. <P>SOLUTION: The hydrogen production device includes: a reformer 1 of bringing a gaseous starting material Gm into reforming reaction, so as to generate a reformed gas Gh; a cooler 23 of cooling the reformed gas from the reformer; and a converter 21 of bringing the reformed gas cooled by the cooler into CO conversion reaction. The device also includes a warming system 22 capable of warming the converter in accordance with driving load conditions. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hydrogen production apparatus for producing hydrogen by steam reforming of a hydrocarbon-based fuel, and more particularly to improvement of the CO converter.

  The hydrogen production apparatus uses a hydrocarbon-based fuel such as city gas, natural gas, or LP gas as a raw material gas, generates a hydrogen-rich reformed gas from the raw material gas by steam reforming, and supplies the reformed gas with a predetermined gas. By performing the treatment, for example, high-purity hydrogen gas is obtained for a fuel cell (for example, Patent Document 1 and Patent Document 2).

  A typical example of a conventional system configuration of such a hydrogen production apparatus is shown in FIG. The hydrogen production apparatus shown in the figure includes a reformer 1 that generates a reformed gas (unconverted reformed gas) Gh by causing a reforming reaction in a mixed source gas Gm obtained by mixing water vapor with a source gas, An unconverted reformed gas cooler 2 that cools the reformed gas Gh from the reformer 1 to a predetermined temperature using cooling water as a refrigerant, a conversion reaction (CO conversion reaction) into the reformed gas Gh cooled by the cooler 2 ) To convert carbon monoxide in the reformed gas Gh into carbon dioxide (CO converter) 3, and the converted reformed gas Ghs from the converter 3 is cooled using cooling water as a refrigerant. A reforming gas cooler 4 and a purifying device 5 that purifies the converted reformed gas Ghs into a high-purity hydrogen gas Hg are provided.

  FIG. 7 shows an example of a specific configuration of the converter 3. The converter 3 includes a vessel 11 having a pressure vessel structure. The container 11 is provided with an inlet nozzle 12 for taking in the reformed gas Gh from the reformer 1 in the upper part (upstream side), and an outlet for taking out the CO-converted reformed gas Ghs in the lower part (downstream side). A nozzle 13 is provided, and a buffer plate 14 for making the flow of the reformed gas Gh flowing from the inlet nozzle 12 uniform inside the container 11 is provided close to the downstream end of the inlet nozzle 12.

  The container 11 is provided with a conversion catalyst layer 15 formed by filling a conversion catalyst in the form of pellets of a predetermined size. The conversion catalyst layer 15 is supported by a catalyst holding plate 17 supported non-constrained by a support lug 16 protruding from the inner peripheral surface of the container 11, that is, supported so as to be free in the horizontal direction in the figure. It is formed so as to hold. The catalyst holding plate 17 is configured to allow gas to pass through while preventing the conversion catalyst from flowing out. Specifically, the catalyst holding plate 17 has a structure in which a large number of through holes (not shown) having a size that does not allow passage of the conversion catalyst are formed. Here, the reason why the catalyst holding plate 17 is non-constrainedly supported by the support lugs 16 is to prevent the influence of the radial thermal expansion of the container 11 due to the temperature rise on the catalyst holding plate 17.

  The container 11 is provided with a heat retaining structure configured to have a predetermined heat dissipation property by being covered with an appropriate heat insulating material 18. Here, the predetermined heat dissipation in the heat retaining structure of the container 11 means that the temperature in the converter exceeds the upper limit of the appropriate temperature described below (for example, 300 ° C.) under the condition that heat is generated by the conversion reaction as the exothermic reaction in the converter 3. It means that the heat is dissipated.

  The operation of such a hydrogen production apparatus is performed as follows. A mixed raw material gas Gm obtained by mixing the raw material gas and water vapor in the mixer 19 flows into the reformer 1. In the reformer 1, the reformed gas Gh is generated from the mixed raw material gas Gm by a reforming reaction. The reforming reaction is an endothermic reaction. Therefore, in the reformer 1, for example, the reforming reaction proceeds while being heated by a heated gas of about 900 ° C., and the reformed gas Gh is generated at a high temperature of about 500 ° C., for example.

  The reformed gas Gh generated by the reformer 1 is cooled to a predetermined temperature by the cooler 2. The predetermined temperature is an appropriate temperature in the converter 3. The appropriate temperature in the converter 3 is given by the use temperature of the conversion catalyst and the condensation temperature of the water vapor remaining in the reformed gas Gh. Here, the condensing temperature of the remaining steam of the reformed gas Gh defines an appropriate temperature in the converter 3 because the mist generated by the condensation of the steam adversely affects the conversion catalyst of the conversion catalyst layer 15. This is so as not to cause condensation. There are two types of conversion catalysts, one for high temperature and one for low temperature. The conversion catalyst in the example shown in the figure is a low-temperature copper-zinc system, and its use temperature is, for example, 300 ° C. or less. On the other hand, the condensation temperature of the remaining steam of the reformed gas Gh correlates with the system pressure in the hydrogen production apparatus, and is 180 ° C. in the case of a general system pressure of 0.8 Mpa. Therefore, in the cooler 2, the reformed gas Gh is cooled to a temperature of 200 to 300 ° C. using cooling water or the like, but usually considering the supply of heat by the conversion reaction, which is an exothermic reaction. Is cooled to about 230 ° C.

The reformed gas Gh cooled by the cooler 2 flows into the converter 3. In the converter 3, the reformed gas Gh comes into contact with the conversion catalyst of the conversion catalyst layer 15, thereby converting carbon monoxide contained in the reformed gas Gh into carbon dioxide as CO + H ₂ O → CO ₂ + H _2. A reaction is caused, whereby a converted reformed gas Ghs having a carbon monoxide concentration of, for example, 1% or less is obtained.

  The converted reformed gas Ghs flowing out from the converter 3 is cooled by the cooler 4 and then flows into the purifier 5. The purifier 5 purifies the converted reformed gas Ghs to obtain a high purity hydrogen gas Hg. This hydrogen gas Hg is supplied to, for example, a fuel cell (not shown). In the purifier 5, purge gas Pg is generated as exhaust gas along with purification. This purge gas Pg is sent to the reformer 1.

JP 2004-189510 A JP-A-8-188783

  In the hydrogen production apparatus as described above, a low load operation may be performed in addition to a 100% load rated operation. In the low load operation, the flow rate of the raw material gas, the reformed gas, etc. is smaller than that in the rated operation. When such low-load operation is performed, if the amount of heat generated in the conversion reaction is reduced beyond a certain level due to a decrease in the flow rate of the reformed gas flowing into the converter, the balance with the heat dissipation in the heat retaining structure of the converter described above. Collapses, and there is a possibility that the temperature in the converter will be in a state where it falls below the lower limit of the appropriate temperature (for example, 180 ° C.). When the temperature in the converter falls below the lower limit, the water vapor remaining in the reformed gas condenses, and the conversion reaction efficiency decreases due to the adverse effect on the conversion catalyst due to the mist generated thereby. This leads to a state in which the concentration of carbon monoxide in the gas exceeds a specified value. This has a great influence on the purification in the purification apparatus. In other words, carbon monoxide is the most difficult gas to remove in the refining equipment, and if the carbon monoxide concentration in the converted reformed gas exceeds the specified value, purification until sufficient removal of toxic carbon monoxide is performed. There is a possibility that it cannot be done with a refining device.

  The present invention has been made on the basis of the above-described knowledge. For a hydrogen production apparatus that can perform low load operation in addition to rated operation, the temperature in the converter can be set even during the low load operation. An object is to be able to stably maintain the temperature within an appropriate temperature range.

  In the present invention, in order to solve the above-described problems, a reformer that generates a reformed gas by causing a reforming reaction in a raw material gas, a cooler that cools the reformed gas from the reformer, and the cooling Provided with a conversion catalyst layer for forming a CO conversion reaction in the reformed gas cooled in the reactor, and the conversion catalyst layer formed by filling the conversion catalyst for the CO conversion reaction is provided therein. In a hydrogen production apparatus having a container, a heating system is provided that is capable of heating the converter according to an operating load state.

  As described above, since the converter can be heated according to the operating load state, the amount of reformed gas flowing into the converter during the low load operation can be reduced, so that the heat generation amount in the conversion reaction can be reduced. The decrease can be compensated for by heating by the heating system, and therefore the temperature in the converter can be stably maintained in the appropriate temperature range even during low load operation.

  In the present invention, the reformed gas is used as the warming gas in the warming system for the hydrogen production apparatus as described above. In this way, the heating system can be realized with a simpler structure.

  In the present invention, in the hydrogen production apparatus as described above, the heating system is a heating gas flow path for heating the inside of the container by flowing the heating gas, and the reformed gas is used as the heating gas. And a heating gas supply line for supplying the heated gas flow path, and a heated gas return line for returning the heated gas flowing down the heated gas flow path, and from the cooler to the converter A first valve for controlling the flow state of the reformed gas from the reformer to the cooler, and the flow state of the reformed gas in the heated gas supply line And a heating control system including a stop valve control means for performing opening / closing control of each of the first and second valves based on the operating load state. Such a configuration is particularly effective in making the heating system a simple structure.

  In the present invention, in the hydrogen production apparatus as described above, the warming gas flow path is formed so as to cover the periphery of the container, or is provided inside the container and covers the periphery of the conversion catalyst layer. It is supposed to be formed in this way. By setting it as such a heating gas flow path, the heating for maintaining stably the temperature in a converter in a suitable temperature range can be performed more effectively.

  According to the present invention as described above, with respect to a hydrogen production apparatus that can perform low-load operation in addition to rated operation, the temperature in the converter can be stably maintained within an appropriate temperature range even during the low-load operation. Will be able to.

  Hereinafter, modes for carrying out the present invention will be described. FIG. 1 shows a system configuration of the hydrogen production apparatus according to the first embodiment, and FIG. 2 shows a specific configuration example of the converter. In the hydrogen production apparatus of this embodiment, the reformed gas Gh flowing into the converter 21 is cooled by using the purge gas Pg from the purification apparatus 5 as a refrigerant, and a heating system 22 for heating the converter 21. Is provided, and is basically the same as the conventional hydrogen production apparatus described above except for these characteristic configurations. Therefore, the characteristic configuration will be mainly described below, and the same reference numerals as those in FIGS. 6 and 7 are used for elements common to the conventional hydrogen production apparatus, and the description thereof will be omitted as appropriate.

  In order to cool the reformed gas Gh that flows into the converter 21 using the purge gas Pg as a refrigerant, a gas refrigerant type is used for the cooler 23 for the unconverted reformed gas, and the purge gas Pg flows to the cooler 23. A refrigerant circulation system 24 is provided. The refrigerant circulation system 24 includes a supply pipe 26, a bypass pipe 27, a recovery pipe 28, and a refrigerant supply amount control system 29.

  The supply line 26 is provided so as to connect the purifier 5 and the cooler 23 so that the purge gas Pg discharged from the purifier 5 can be directly supplied to the cooler 23. The bypass line 27 is provided by being branched from the middle of the supply line 26 so that a part of the purge gas Pg flowing through the supply line 26 can be bypassed to the cooler 23, The purge gas Pg can be returned to the reformer 1. The recovery line 28 is adapted to merge the purge gas Pg that has passed through the cooler 23 with the bypass line 27. The refrigerant supply amount control system 29 flows into the first flow rate adjustment valve 31 attached in the middle of the supply line 26, the second flow rate adjustment valve 32 attached in the middle of the bypass line 27, and the converter 21. A temperature measurement means 33 for measuring the temperature of the reformed gas Gh, and a flow rate adjustment valve control means 34 for controlling the opening of the flow rate adjustment valve 31 and the flow rate adjustment valve 32 based on measurement data obtained by the temperature measurement means 33; Has been.

  The heating system 22 for heating the converter 21 includes a heating gas channel 35, a heating gas supply pipe 36, a heating gas return pipe 37, and a heating control system 38. Yes.

  As shown in FIG. 2, the warming gas flow path 35 is formed so as to mainly cover the periphery of the conversion catalyst layer 15 and cover the periphery of the container 11, and the warming gas inlet 41 and the outlet 42. Is provided. The warming gas channel 35 heats the inside of the container 11, specifically, the conversion catalyst layer 15 from the outer peripheral portion thereof by flowing the warming gas.

  The heated gas supply line 36 is connected to the upstream end in the middle of the cooler / converter line 43 connecting the cooler 23 and the converter 21, and the downstream end is the inlet of the heated gas flow path 35. The reformed gas Gh immediately after flowing down from the cooler 23 can be supplied to the heated gas passage 35 as a heated gas.

  The warming gas return pipe 37 is provided so that the upstream end is connected to the outlet 42 of the warming gas flow path 35 and the downstream end is connected to the cooler / converter pipe 43. The heated gas that has flowed down the heated gas flow path 35, that is, the reformed gas Gh, is returned to the cooler / converter conduit 43.

  The warming control system 38 is attached to the cooler / converter conduit 43 upstream of the connection portion of the warming gas supply conduit 36, and determines the flow of the reformed gas Gh from the cooler 23 to the converter 21. Controlled, more specifically, a first stop valve (first valve) 44 for switching the flow of the reformed gas Gh on and off, and the heated gas supply line 36 are attached to the heated gas supply pipe. To the second stop valve (second valve) 45 that controls the flow of the reformed gas Gh in the passage 36, more specifically, to switch the flow of the reformed gas Gh on and off, and to the converter 21. It includes a stop valve control means (valve control means) 46 that controls opening and closing of the first and second stop valves 44 and 45 based on the inflow amount of the reformed gas Gh.

  Below, the operating method of the hydrogen production apparatus in this embodiment as mentioned above is demonstrated. First, cooling of the reformed gas Gh by the cooler 23 will be described. The cooling of the reformed gas Gh by the cooler 23 is performed so that the temperature of the reformed gas Gh is set to a temperature in the appropriate temperature range (for example, about 230 ° C.) in the converter 21 as described above. Specifically, based on the temperature data obtained by the temperature measuring means 33, that is, the temperature data of the reformed gas Gh flowing into the converter 21, the flow rate adjusting valve control means 34 performs the first flow rate adjusting valve 31 and the second flow rate adjusting valve 31. By controlling the opening degree of each flow rate adjustment valve 32, the amount of purge gas Pg flowing into the cooler 23 is adjusted, thereby adjusting the cooling capacity of the cooler 23 and adjusting the reformed gas Gh to the appropriate temperature range temperature. Cool down.

  Next, the operation according to the load state, specifically, the rated operation with 100% load and the low load operation with a smaller load will be described. The rated operation or the low load operation is determined by the amount of the mixed raw material gas Gm introduced into the reformer 1 or the amount of the reformed gas Gh flowing into the converter 21. It is given to the valve control means 46.

  During the rated operation, the converter 21 is not heated by the heating system 22. Specifically, the stop valve control means 46 opens the first stop valve 44 and closes the second stop valve 45. Therefore, the reformed gas Gh flowing out of the cooler 23 flows down the cooler / converter pipe 43 and flows into the converter 21.

  On the other hand, at the time of low load operation, the operation is accompanied by heating of the converter 21 by the heating system 22. Specifically, the stop valve control means 46 closes the first stop valve 44 and opens the second stop valve 45. Therefore, the reformed gas Gh flowing out from the cooler 23 flows down the heated gas supply pipe 36 and flows into the heated gas flow path 35 from the inlet 41. The reformed gas Gh that has flowed into the warming gas flow path 35 flows down the warming gas flow path 35 while acting to heat the conversion catalyst layer 15 from the outer peripheral portion thereof, and reaches the outlet 42. It flows out to the warming gas return line 37 and flows into the cooler / converter line 43 and then flows down the cooler / converter line 43 and flows into the converter 21.

  According to the first embodiment as described above, the temperature of the reformed gas Gh can be adjusted more effectively by cooling the reformed gas Gh using the purge gas Pg as a refrigerant. Become. In other words, in the case of liquid refrigerants such as cooling water, the temperature control range by adjusting the flow rate is as narrow as several degrees Celsius, but in the case of gas refrigerants, the temperature control range by adjusting the flow rate can be greatly increased. As a result, the temperature of the reformed gas Gh can be adjusted more effectively.

  Further, since the heating system 22 is provided so that the converter 21 can be heated, the amount of reformed gas flowing into the converter 21 during low-load operation decreases, thereby reducing the heat generation amount in the conversion reaction. However, the decrease can be compensated for by heating by the heating system 22, and therefore, the temperature in the converter can be stably maintained in an appropriate temperature range even during low load operation.

  Further, since the reformed gas is used as the heating gas in the heating system 22, the heating system 22 can be realized with a simple structure.

  Further, the heated gas flow path 35 is formed so as to mainly cover the periphery of the conversion catalyst layer 15 and cover the periphery of the container 11, so that the temperature in the converter, more specifically, the temperature of the conversion catalyst layer 15 is formed. Can be more effectively heated to keep the temperature within the appropriate temperature range. That is, according to the warming gas flow path 35, the conversion catalyst layer 15 can be heated from its surroundings, and the outer peripheral portion is heated according to the characteristics of the conversion catalyst layer 15 so that the temperature is likely to decrease due to heat dissipation. As a result, more effective heating can be performed.

  FIG. 3 shows a system configuration of the hydrogen production apparatus according to the second embodiment. The hydrogen production apparatus of the present embodiment is characterized in that the raw material gas Gr is used as the gas refrigerant of the cooler 23. Except for this, the hydrogen production apparatus is the same as the hydrogen production apparatus in the first embodiment. Therefore, hereinafter, the characteristic configuration in the present embodiment will be mainly described, and the elements common to the hydrogen production apparatus in the first embodiment will be denoted by the same reference numerals as those in FIG. 1, and the description thereof will be omitted as appropriate. To do.

  In order to use the raw material gas Gr as the refrigerant of the cooler 23, a refrigerant circulation system 51 for flowing the raw material gas Gr to the cooler 23 is provided. The refrigerant circulation system 51 is basically the same as the refrigerant circulation system 24 of FIG. 1, and is different in the supply pipeline 52 and the bypass pipeline 53. Specifically, the supply line 52 is provided so as to connect the reformed gas supply source (not shown) and the cooler 23, and feeds the raw material gas Gr supplied from the reformed gas supply source to the cooler 23. It can be supplied directly. On the other hand, the bypass line 53 is provided to be branched from the middle of the supply line 52 so that a part of the raw material gas Gr flowing through the supply line 52 can be bypassed to the cooler 23. The raw material gas Gr for the bypass is supplied to the mixer 19.

  By using the raw material gas Gr as the refrigerant in this way, as a result, the raw material gas Gr can be preliminarily heated, and the reforming reaction in the reformer 1 can be caused more efficiently. .

  FIG. 4 shows a system configuration of a hydrogen production apparatus according to the third embodiment. The hydrogen production apparatus of the present embodiment is characterized by the heating system 61, and is the same as the hydrogen production apparatus of the first embodiment except for that. Therefore, hereinafter, the characteristic configuration in the present embodiment will be mainly described, and the elements common to the hydrogen production apparatus in the first embodiment will be denoted by the same reference numerals as those in FIG. 1, and the description thereof will be omitted as appropriate. To do.

  The heating system 61 is basically the same as the heating system 22 in FIG. 1, and is different in the heating gas supply pipe 62 and the heating gas return pipe 63, and the first stop valve 44 is attached. There is a difference in position. Specifically, the heated gas supply line 62 connects the upstream end to the middle of the reformer / cooler line 64 connecting the reformer 1 and the cooler 23, and warms the downstream end. It is provided so as to be connected to the gas flow path 35, so that the reformed gas Gh before being cooled by the cooler 23 can be supplied as a heated gas to the heated gas flow path 35, and the heated gas return pipe 63. The upstream end is connected to the outlet 42 of the heated gas passage 35 and the downstream end is connected to the reformer / cooler conduit 64. The warmed gas flowing down is returned to the reformer / cooler line 64, and the first stop valve 44 is connected to the reformer / cooler line 64 of the warmed gas supply line 62. The reformer / cooler pipe downstream from the connection position to the upstream side and upstream from the connection position to the reformer / cooler pipe line 64 of the heated gas return pipe 63 It is attached to the 64.

  In the case of such a heating system 61, the rated operation and the low load operation are performed as follows. First, during rated operation, the stop valve control means 46 opens the first stop valve 44, while the second stop valve 45 is closed, and the reformed gas Gh from the reformer 1 is reformer / cooled. It flows down the inter-unit line 64 and flows into the cooler 23, where it is cooled and then flows into the converter 21.

  On the other hand, at the time of low load operation, the stop valve control means 46 closes the first stop valve 44, while opening the second stop valve 45, and the reformed gas Gh from the reformer 1 is cooled by the cooler 23. To the heated gas supply pipe 62, and flows down to the heated gas flow path 35. The reformed gas Gh that has flowed into the warming gas flow path 35 flows down the warming gas flow path 35 while acting to heat the conversion catalyst layer 15 from the outer peripheral portion thereof, and reaches the outlet 42. It flows out into the warming gas return line 37 and flows into the reformer / cooler line 64 and then flows down the reformer / cooler line 64 into the cooler 23 where it is cooled. After that, it flows into the converter 21.

  FIG. 5 shows the configuration of the converter in the hydrogen production apparatus according to the fourth embodiment. The converter 71 is characterized by the heated gas flow path 72, and is the same as the converter 21 of the hydrogen production apparatus in the first embodiment except for that. Therefore, hereinafter, the characteristic configuration in the present embodiment will be mainly described, and the same reference numerals as those in FIG. 2 are used for the elements common to the converter 21 in the first embodiment, and the description thereof will be omitted as appropriate. To do.

  The heated gas flow path 72 is formed so as to cover the periphery of the conversion catalyst layer 15 inside the container 11. Along with the heated gas flow path 72, a conversion catalyst holding cylinder 73 is provided inside the container 11, and the conversion catalyst layer 15 is formed by filling the conversion catalyst holding cylinder 73 with the conversion catalyst. ing. The bottom plate 74 of the conversion catalyst holding cylinder 73 has the same structure as the catalyst holding plate 17 of FIG. 7 and is supported by the container 11 via a support lug 76 provided with a seal portion 75.

  Similarly to the warming gas channel 35 in the first embodiment, the warming gas channel 72 in the present embodiment also more effectively performs heating for stably keeping the temperature of the conversion catalyst layer 15 in the appropriate temperature range. It can be carried out.

It is a figure which shows the system | strain structure of the hydrogen production apparatus by 1st Embodiment. It is a figure which shows the specific structural example of the converter in FIG. It is a figure which shows the system | strain structure of the hydrogen production apparatus by 2nd Embodiment. It is a figure which shows the system | strain structure of the hydrogen production apparatus by 3rd Embodiment. It is a figure which shows the structure of the converter in the hydrogen production apparatus by 4th Embodiment. It is a figure which shows the system | strain structure of the conventional hydrogen production apparatus. It is a figure which shows the specific structural example of the converter in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reformer 2, 23 Cooler 3, 21, 71 Converter 11 Container 15 Conversion catalyst layer 22, 61 Heating system 35, 72 Heating gas flow path 36, 62 Heating gas supply line 37, 63 Heating Gas return line 38 Heating control system 44 First stop valve (first valve)
45 Second stop valve (second valve)
46 Stop valve control means (valve control means)
Gh Reformed gas Gm Raw material gas

Claims (4)

A reformer that generates a reformed gas by causing a reforming reaction in the raw material gas, a cooler that cools the reformed gas from the reformer, and CO conversion into the reformed gas cooled by the cooler In a hydrogen production apparatus comprising a converter for generating a reaction, the converter having a container in which a conversion catalyst layer formed by filling a conversion catalyst for the CO conversion reaction is provided.
2. A hydrogen production apparatus, comprising: a heating system capable of heating the converter according to an operating load state.   The hydrogen production apparatus according to claim 1, wherein the reformed gas is used as a heating gas in the heating system.   The warming system includes a warming gas channel that warms the inside of the container by flowing the warming gas, and a warming gas that supplies the reformed gas as the warming gas to the warming gas channel A reforming gas flowing from the cooler to the converter, or the reformer, comprising a supply duct and a warming gas return duct for returning the warmed gas flowing down the warming gas flow path A first valve that controls the flow state of the reformed gas from the engine to the cooler, a second valve that controls the flow state of the reformed gas in the heated gas supply line, and the operating load state The hydrogen production apparatus according to claim 2, further comprising a heating control system including stop valve control means for performing opening / closing control of each of the first and second valves. The heated gas flow path is formed so as to cover the periphery of the container, or is formed so as to cover the periphery of the conversion catalyst layer inside the container. The hydrogen production apparatus according to claim 3.

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