JP2006282424A - Hydrogen generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an efficient system having improved reforming efficiency and a hydrogen generator capable of preventing the deterioration of a catalyst and having high durability and reliability by transferring the heat generated in a heating section to the whole catalyst in order to utilize the whole catalyst and to prevent an overload. <P>SOLUTION: A heat transfer plate 22 projected into a reforming section 8 is installed. Thereby, the heat generated at a combustor 5 is transferred to the whole catalyst, a sufficient performance can be secured, and the partial overheat of the catalyst or the partial reaction can be prevented. Accordingly, the efficient system having improved reforming efficiency and the hydrogen generator capable of preventing the deterioration of the catalyst and having high durability and reliability are obtained. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hydrogen generator for obtaining hydrogen used as a fuel for a polymer electrolyte fuel cell.

  The hydrogen generator generates hydrogen to be used as a fuel for a polymer electrolyte fuel cell that is being developed recently, and a hydrocarbon steam reforming method is often used as a method for producing this hydrogen. The steam reforming method is a method in which methane, ethane, propane, butane, city gas, LP gas, natural gas, and other hydrocarbon gases are reformed with steam to generate a hydrogen-rich reformed gas. In the steam reforming method, these hydrocarbons are converted into hydrogen-rich reformed gas by a catalytic reaction in the reforming section. The obtained hydrogen-rich reformed gas is used by reducing CO in the CO removal section.

  FIG. 4 is a block diagram showing a raw material using a steam reformer, from supply of steam to the outlet of hydrogen gas. It comprises a heating section having a combustion section and a reforming section having a reforming catalyst. In the reforming section that has reached a high temperature, the hydrocarbon reacts with the steam to produce a hydrogen-rich reformed gas.

  When the hydrocarbon is used as a raw material, the reforming section needs to be heated to a temperature of 500 to 700 ° C. As the reforming catalyst, for example, a Ni-based or Ru-based catalyst is used. Since the reforming catalyst is poisoned by sulfur compounds in the raw material gas and deteriorates performance, it is introduced into the desulfurization section in order to remove those sulfur compounds. Next, steam from a steam generation section provided separately is added and mixed to be introduced into the reforming section of the steam reformer.

  The reforming reaction when the raw material gas is methane is represented by CH4 + 2H2O → CO2 + 4H2. The generated reformed gas contains about 8 to 15% of carbon monoxide (CO) generated in addition to unreacted methane, unreacted water vapor, and generated carbon dioxide. For this reason, the reformed gas is applied to the CO conversion section to remove the carbon monoxide by converting it to carbon dioxide and hydrogen. For example, a Fe—Cr based catalyst, a Cu—Zn based catalyst, or a Pt catalyst is used in the CO conversion portion. The reaction in the CO conversion part is CO + H 2 O → CO 2 + H 2, and the steam necessary for the steam uses the residual steam in the reforming part. The reformed gas exiting from the CO conversion section is composed of unreacted methane, excess steam, hydrogen, and carbon dioxide. However, this reformed gas does not completely remove CO, but contains CO although it is less than about 1%.

  The allowable concentration of CO in the fuel hydrogen supplied to the fuel cell is about 10 ppm, and if it exceeds this, the cell performance is significantly deteriorated. Therefore, it is necessary to remove the CO component as much as possible before introducing it into the fuel cell. For this reason, the reformed gas is applied to the CO removal section after the CO concentration is lowered to around 1% by the CO shift section. An oxidant such as air is added to the CO removing unit, and CO is removed by changing the CO gas from 2CO + O 2 → 2CO 2 and CO 2 to reduce the CO concentration of the reformed gas to 10 ppm or less.

  Conventionally, this type of hydrogen generator has focused on uniformly mixing raw materials and water vapor in order to improve performance (see, for example, Patent Document 1).

  FIG. 5 is a cross-sectional view of the reforming reactor of the steam reformer. The reforming reactor is provided with a raw material evaporation introducing portion 3 that leads to the reforming reaction portion 2 as a mixed raw material gas that is uniformly mixed with a gaseous raw material that is separately supplied while vaporizing a liquid raw material, in the upper part of the cylindrical container 1. The lower part in the container 1 is provided with a reforming reaction part 2 for reforming the mixed raw material gas by the reforming catalyst and a heating part 4 for supplying reaction heat to the reforming reaction part 2. The reforming reaction section 2 is formed in a cylindrical shape as a whole, and is disposed coaxially with the cylindrical container 1 with a slight space between the bottom of the container 1 and the bottom surface of the container 1. The heating unit 4 includes a combustor 5 provided on the bottom surface of the container 1, a combustion gas passage 6 through which the combustion gas of the combustor 5 passes upward along the axis of the container 1, and the combustion gas. And an exhaust pipe 7 provided on the upper surface of the container 1 in order to exhaust the air from the container 1.

  For this reason, the reforming raw material of the reforming reactor, that is, the mixed raw material gas is steam (water) obtained by vaporizing methane as a gas raw material and water as a liquid raw material. Water is dropletized and mixed into the supplied methane, and the dropped water becomes fine water droplets and rides on the flow of methane. 3 is supplied. In the course of flowing down the raw material evaporation introducing unit 3, the gas / liquid mixed phase is vaporized (evaporated) in the gas / liquid mixed phase, and the gas / liquid mixed phase becomes mixed raw material gas, which is supplied to the reaction unit 2. Is done.

  That is, the evaporation in the raw material evaporation introducing unit 3 is an evaporation mode in which moisture is humidified to the saturated vapor pressure in the methane gas phase while the boiling point is sequentially changed in the flow direction of the raw material due to the presence of methane as the second component. Thus, stable evaporation can always be realized at a constant evaporation rate.

Therefore, it is always possible to supply a uniform mixed raw material gas without pulsation that is uniformly mixed. In addition, since a stable mixed source gas without pulsation is supplied, battery voltage fluctuations and stable combustion of the heating unit 4 of the reforming reaction unit 2, that is, generation of CO, NO, and the like are suppressed, and the system is operated. It can be performed stably. Moreover, since the reforming reaction gas as the mixed raw material gas is supplied to the reforming reaction section 2 with a uniform composition, carbon deposition on the reforming catalyst and a decrease in the reforming rate are suppressed as in the conventional case.
JP 2003-119001 A

  However, in the conventional configuration, the amount of heat of reaction when the gas mixed with the raw material flowing in the reforming section and water vapor reacts with the catalyst is insufficient, and sufficient performance cannot be ensured. That is, in order to ensure sufficient reaction performance, it is necessary to always supply the amount of heat necessary for the reaction to each part of the catalyst. The catalyst is heated from the wall surface of the reforming section filled with the catalyst by the heating means, and the internal catalyst is thermally transferred by heat conduction of the catalyst particles and heat transfer of the internal gas. Therefore, the amount of heat transfer is greatly different between a catalyst close to the wall surface and a catalyst far from the wall surface. On the other hand, the reaction characteristics of the catalyst are highly correlated with temperature.

  For example, the characteristic of 90% reaction at 700 ° C. in a certain amount of gas and catalyst becomes 75% reaction at 600 ° C. and 55% reaction at 500 ° C. Even if the raw material and water vapor flow uniformly in each part of the catalyst, in the case of a catalyst far from the wall surface, the raw material and water vapor undergo an endothermic reaction by the catalyst, but the amount of heat from the heating means is insufficient and the temperature decreases. Therefore, a gas that does not sufficiently undergo the hydrogen reforming reaction by the raw material catalyst exits from the reforming section. For this reason, the reforming efficiency is lowered, and deterioration due to an excessive load on the reforming catalyst occurs, so that long-term reliability cannot be secured and system efficiency is lowered.

  The present invention solves the above-mentioned conventional problems, and by forming a heat transfer plate protruding inside the reforming section, the heat generated in the heating section is transferred to the entire catalyst in the reforming section, and the catalyst The purpose of the present invention is to provide an efficient and reliable hydrogen generator by preventing the deterioration of the efficient system and catalyst by improving the reforming efficiency by preventing the entire utilization and overload.

  In order to solve the above-mentioned conventional problems, the hydrogen generator of the present invention comprises a means for supplying a raw material, a means for supplying water, a heating means, a reforming section filled with a catalyst, a CO conversion section, and a CO conversion section. A removal part is connected sequentially, and a heat transfer plate protruding inside the reforming part is configured at a contact part between the heating means and the reforming part. As a result, the heat generated in the heating section can be transferred to the entire catalyst in the reforming section through the heat transfer plate protruding into the reforming section.

  That is, heating can be performed from the wall surface of the reforming unit and the heat transfer plate, and a catalyst close to the wall surface and a catalyst far from the wall surface can be heated in the same manner, and a sufficient amount of heat transfer can be ensured. Therefore, in order to secure the endothermic reaction performance, the amount of heat necessary for the reaction is always supplied to each part of the catalyst to ensure the reaction heat quantity when the gas mixed with the raw material flowing in the reforming section and the steam reacts with the catalyst. As a result, sufficient performance can be ensured.

  Moreover, being able to react uniformly in the whole catalyst can prevent partial overheating and local reaction of the catalyst, and can maintain the performance in a durable manner.

  The hydrogen generator of the present invention is constituted by a heat transfer plate protruding inside the reforming section, so that heat generated in the heating section is transferred to the entire catalyst in the reforming section, and the entire catalyst is utilized and overloaded. By preventing the deterioration of the reforming efficiency, the efficient system and the deterioration of the catalyst can be prevented, and the hydrogen generator with high durability and reliability can be obtained.

  According to a first aspect of the present invention, a means for supplying a raw material, a means for supplying water, a heating means, a reforming section filled with a catalyst, a CO conversion section, and a CO removal section are sequentially connected, and the heating means and the The contact part of the reforming part is constituted by a heat transfer plate protruding inside the reforming part.

  As a result, the heat generated in the heating section can be transferred to the entire catalyst in the reforming section through the heat transfer plate protruding into the reforming section. That is, heating can be performed from the wall surface of the reforming unit and the heat transfer plate, and a catalyst close to the wall surface and a catalyst far from the wall surface can be heated in the same manner, and a sufficient amount of heat transfer can be ensured. Therefore, in order to secure the endothermic reaction performance, the amount of heat necessary for the reaction is always supplied to each part of the catalyst to ensure the reaction heat quantity when the gas mixed with the raw material flowing in the reforming section and the steam reacts with the catalyst. As a result, sufficient performance can be ensured.

  That is, the reaction characteristic of reacting the raw material and water vapor with hydrogen by the catalyst greatly correlates with the temperature. The reaction proceeds when the amount of the catalyst is increased or the raw material flow rate is decreased, but the characteristic of 90% reaction at 700 ° C reacts with a certain amount of gas and catalyst, reacts 75% at 600 ° C and 55% at 500 ° C. become. When the raw material and water vapor flow uniformly in each part of the catalyst, the catalyst close to the wall surface receives sufficient heat from the wall surface, and the raw material and water vapor undergo endothermic reaction by the catalyst, and the catalyst far from the wall surface is similarly removed from the heat transfer plate. Since the raw material and water vapor undergo an endothermic reaction by the catalyst in response to the necessary heat, the amount of heat necessary for the reaction is sufficient and the temperature can be maintained without decreasing. Therefore, the hydrogen reforming reaction by the raw material catalyst is sufficiently performed in each part of the catalyst, and all the gas is reformed and leaves the reforming section.

  In addition, the ability to react uniformly over the entire catalyst is due to deterioration of sintering, etc. due to overheating of the catalyst temperature near the wall surface by increasing the set temperature of the reforming part in order to ensure the reforming reaction performance of the catalyst in the part far from the wall surface. The performance can be maintained in a durable manner.

  Therefore, the heat generated in the heating section is transferred to the entire catalyst in the reforming section to prevent the use of the entire catalyst and overload, thereby preventing an efficient system and catalyst deterioration due to improved reforming efficiency. And a highly durable hydrogen generator.

  In the second invention, in particular, in the hydrogen generator of the first invention, a plurality of heat transfer plates are formed at approximately equal intervals in the reforming section. For this purpose, the catalyst filled in the reforming section can be divided and arranged in a large number by a plurality of heat transfer plates. Since the heat transfer plates are equally spaced, the catalyst is uniformly divided in volume. For this reason, heat transfer from the heating unit can be uniformly conducted to each part of the catalyst, and the heat necessary for the catalytic reaction is sufficiently supplied so that the catalyst temperature does not decrease, thereby improving the reforming efficiency. Efficient system and catalyst deterioration can be prevented and durability and reliability can be increased.

  According to a third aspect of the invention, in particular, the heat transfer plate of the hydrogen generator of the first aspect of the invention or the second aspect of the invention is configured to protrude in parallel with the flow direction of the raw material gas flowing in the catalyst in the reforming section. The raw material can be heated by the heat transfer plate from the time it enters the reforming section until it leaves, and the catalytic reaction can be promoted uniformly. In addition, the system can be kept stable without increasing the flow pressure loss of the raw material gas flowing through the reforming section.

  That is, the reforming of raw material into hydrogen by water vapor is an endothermic reaction. Therefore, in order to promote the reforming reaction uniformly, it is necessary to continuously supply heat to the gas near the reacting catalyst. Therefore, by adopting a configuration in which the raw material gas entering the reforming section can be sequentially heated by the heating means of the heat transfer plate, reforming of the raw material into hydrogen progresses from the inlet to the outlet of the reforming section, and is further improved. An efficient system can be achieved by improving quality efficiency.

  In the fourth aspect of the invention, in particular, the heat transfer plate of the hydrogen generator according to any one of the first to third aspects of the invention is configured such that the surface thereof is uneven, so that the heat transfer area is enlarged and the vicinity of the heat transfer plate is increased. The flow of the raw material gas is disturbed, the boundary layer can be thinned, the contact area between the catalyst and the heat transfer plate can be increased, and the heat conducted from the heating part to the heat transfer plate can be promoted by the catalyst. Sufficient heat required for the reaction can be supplied to prevent the deterioration of the efficient system and catalyst by improving the reforming efficiency, thereby improving the durability and reliability.

  In the fifth aspect of the invention, in particular, the hydrogen generator according to any one of the first to fourth aspects of the invention is provided with an auxiliary heat transfer plate that is convex on the surface of the heat transfer plate, and the thickness of the auxiliary heat transfer plate Is thinner than the plate thickness of the heat transfer plate, so that the contact area between the catalyst and the heat transfer plate is greatly increased by the contact area of the auxiliary heat transfer plate without increasing the flow resistance of the raw material gas flowing through the reforming section. It is possible to increase the heat, the heat conducted from the heating part to the heat transfer plate can be accelerated by the catalyst, the heat necessary for the catalytic reaction is sufficiently supplied, and the efficient system by improving the reforming efficiency And the deterioration of the catalyst can be prevented and the durability and reliability can be increased.

  In the sixth aspect of the invention, in particular, the hydrogen generator according to any one of the first to fifth aspects of the invention is integrally formed by using an extrusion molding material or the like on the wall surface of the reforming part in contact with the heating means and the heat transfer plate. As a result, the wall of the reforming section and the heat transfer plate have a low thermal resistance, and the heat from the heating section can be conducted to the heat transfer plate without lowering the temperature, and the heating of the catalyst can be promoted. To improve the efficiency of reforming, and the integral molding of the wall of the reforming part and the heat transfer plate can improve the adhesion reliability and reduce the cost by simplifying the configuration. It becomes possible.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiment.

(Embodiment 1)
FIG. 1 shows a cross-sectional view of a reforming section in a hydrogen generator according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional view of the reforming section. As shown in FIG. 4, the entire hydrogen generator has a structure in which a raw material supply means, a water supply means, a reforming section having a heating means, a CO conversion section, and a CO removal section are sequentially connected. The generated hydrogen gas is used by connecting to a fuel cell.

  In FIG. 1, 8 is a reforming unit that generates hydrogen to be supplied to a fuel cell power generation apparatus using city gas as a raw material, 9 is a means for supplying the raw material connected to the city gas, and 10 is water as water vapor. It is a means for supplying and is connected to the catalyst container 11.

  No. 12 is a catalyst layer filled with a large number of catalyst particles having a catalyst mainly composed of nickel or ruthenium supported on a support of a support such as an iron plate or ceramics. By reacting, a product gas composed of hydrogen, carbon dioxide, and carbon monoxide is produced by reaction. This production reaction is an endothermic reaction occurring at a high temperature of about 500 to 700 ° C. For this reason, high temperature combustion gas is supplied from the combustor 5 as heating means to heat the raw material gas containing water vapor and the catalyst layer 12. The combustor 5 is city gas (natural gas), off-gas (unreacted hydrogen gas) discharged from the fuel cell, or city gas and off-gas are mixed and supplied as fuel from the fuel pipe 13 and ejected from the distributor 14. Combustion air is combusted by being supplied from an air pipe 15 and ejected from an air ejection part 16. Reference numeral 18 denotes a combustion cylinder for preventing the flame 19 generated by the combustor 5 from directly touching the catalyst container 11 and further defining the flow path of the combustion gas 20. The combustion gas 20 flows along the periphery of the catalyst container 11 and is discharged from the exhaust pipe 7 to the outside of the reforming unit 8.

  In the steam reforming unit 8, the raw material gas supplied by the means 9 for supplying the raw material connected to the city gas and the means 10 for supplying water as the steam flows into the catalyst container 11, and the catalyst in the catalyst container 11 is supplied. In the layer 12, the raw material gas is produced by reacting with hydrogen, carbon dioxide and carbon monoxide, and is sequentially connected from the product gas outlet 21 to a CO conversion unit, a CO removal unit, and a fuel cell (not shown).

  The reforming unit 8 is provided with a heat transfer plate 22 protruding inside the reforming unit 8 at a contact portion between the combustor 5 and the reforming unit 8 serving as heating means. The heat transfer plate 22 is made of a material such as metal having good heat conduction performance, and one end thereof is in close contact with the wall surface of the reforming unit 8. In this embodiment, the metal plate is bent in an L shape, and one end is welded and brought into close contact with the catalyst container 11, and the other end protrudes in the catalyst layer 12 to near the outer wall of the catalyst container 11. A plurality of heat transfer plates 22 of the present embodiment are configured in the reforming unit 8 at approximately equal intervals, and provided so as to protrude in parallel with the flow direction of the raw material gas flowing in the catalyst in the reforming unit 8; As shown in FIG. 2, the heat transfer plate 22 is arranged so that the catalyst of the catalyst layer 12 and the heat transfer plate 22 are uniformly brought close to each other so as to divide the catalyst layer 12 of the reforming unit 8 into a large number in the flow direction. The configuration is as follows.

  In the reformed gas to be produced, the CO shift portion contains about 8 to 15% of carbon monoxide (CO) generated in addition to unreacted methane, unreacted water vapor and produced carbon dioxide. For this reason, the reformed gas is provided with a CO conversion section for removing the carbon monoxide by converting it to carbon dioxide and hydrogen. For example, an Fe—Cr based catalyst, a Cu—Zn based catalyst, or a Pt catalyst is used in the CO conversion portion, and the reaction is performed at about 300 ° C.

  For the reaction in the CO conversion section, the steam necessary for CO + H 2 O → CO 2 + H 2 uses the residual steam in the reforming section 8. The reformed gas exiting from the CO conversion section is composed of unreacted methane, excess steam, hydrogen, and carbon dioxide. However, this reformed gas does not completely remove CO, but contains CO although it is less than about 1%. The allowable concentration of CO in the fuel hydrogen supplied to the fuel cell is about 10 ppm, and if it exceeds this, the cell performance is significantly deteriorated. Therefore, it is necessary to remove the CO component as much as possible before introducing it into the fuel cell. For this reason, the reformed gas is provided with a CO removal section after the CO concentration is lowered to around 1% by the CO shift section. The CO removal unit carries a catalyst that selectively oxidizes carbon monoxide, and an oxidant such as air is added to remove CO by changing from 2CO + O2 → 2CO2 and CO2, and the CO concentration of the reformed gas Is reduced to 10 ppm or less. With such a configuration and operation, in a steady state, the raw material gas is reformed to hydrogen, the fuel cell is operated, and power generation is continued.

  The operation and action of the hydrogen generator configured as described above will be described below.

  During operation, the raw material gas is supplied to the catalyst container 11 by means 9 for supplying the raw material connected to the city gas and means 10 for supplying water as water vapor. The raw material gas that has entered the catalyst container 11 undergoes a reaction to become a reformed gas with a large amount of hydrogen by the filled catalyst layers 12 and reaches the product gas outlet 21. Since this reaction is an endothermic reaction, the reaction continues by always heating.

  Heat generated in the combustor 5 serving as a heating unit can be transferred to the entire catalyst layer 12 in the reforming unit through the heat transfer plate 22 protruding into the catalyst container 11 of the reforming unit 8. That is, the catalyst layer 12 can be heated from the wall surface of the catalyst container 11 and the heat transfer plate 22 in the reforming section, and the catalyst close to the wall surface and the catalyst far from the wall surface can be heated in the same manner, so that a sufficient amount of heat transfer can be ensured. Therefore, the amount of heat required for the reaction in each part of the catalyst layer 12 in order to ensure the endothermic reaction performance, the amount of reaction heat when the gas mixed with the raw material flowing in the reforming unit 8 and water vapor reacts with the catalyst. Is always supplied, and sufficient performance can be secured.

  That is, the reaction characteristic of reacting the raw material and water vapor with hydrogen by the catalyst greatly correlates with the temperature. The reaction proceeds when the amount of the catalyst is increased or the raw material flow rate is decreased, but the characteristic of 90% reaction at 700 ° C reacts with a certain amount of gas and catalyst, reacts 75% at 600 ° C and 55% at 500 ° C. become. When the raw material and water vapor flow uniformly in each part of the catalyst, the catalyst close to the wall surface sufficiently receives heat from the wall surface, and the raw material and water vapor undergo endothermic reaction by the catalyst, and the catalyst far from the wall surface similarly heats the heat transfer plate 22. Since the raw material and water vapor undergo an endothermic reaction by the catalyst in response to the necessary heat, the amount of heat necessary for the reaction is sufficient and the temperature can be maintained without decreasing. Therefore, the hydrogen reforming reaction by the raw material catalyst is sufficiently performed in each part of the catalyst, and all the gas is reformed and leaves the reforming section.

  Further, the fact that the entire catalyst of the catalyst layer 11 can react uniformly means that the set temperature of the reforming unit 8 is increased and the catalyst temperature near the wall surface is overheated in order to ensure the reforming reaction performance of the catalyst far from the wall surface. Performance can be maintained in a durable manner without causing deterioration such as sintering.

  Therefore, the heat generated in the combustor 5 of the heating unit is transferred to the entire catalyst of the catalyst layer 12 of the reforming unit 8 to prevent the utilization and overload of the entire catalyst, thereby improving the efficiency of reforming. It is a durable and reliable hydrogen generator that prevents deterioration of the system and catalyst.

  In addition, the heat transfer plate 22 includes a plurality of catalyst layers 12 of the catalyst container 11 of the reforming unit 8 at approximately equal intervals. Therefore, the catalyst filled in the catalyst container 11 of the reforming section can be divided and arranged in a large number by the plurality of heat transfer plates 22. Since the heat transfer plates 22 are equally spaced, the catalyst is uniformly divided in volume. For this reason, heat transfer from the combustor 5 of the heating unit can be uniformly conducted to each part of the catalyst, and the heat necessary for the catalytic reaction is sufficiently supplied so that the catalyst temperature does not decrease, and reforming is possible. Efficient system with improved efficiency and deterioration of catalyst can be prevented and durability and reliability can be increased.

  Further, the heat transfer plate 22 is configured to protrude in parallel with the flow direction of the raw material gas flowing in the catalyst in the catalyst container 11 of the reforming unit 8, so that the raw material passes from entering the catalyst container 11 to exiting. Heat can be heated by the intermediate heat transfer plate 22 and the catalytic reaction can be promoted uniformly. Further, the flow pressure loss of the raw material gas flowing through the catalyst container 11 of the reforming section is not increased, and the system can be kept stable. That is, the reforming of raw material into hydrogen by water vapor is an endothermic reaction. Therefore, in order to promote the reforming reaction uniformly, it is necessary to continuously supply heat to the gas near the reacting catalyst. Therefore, by adopting a configuration in which the raw material gas that has entered the catalyst container 11 of the reforming unit 8 can be sequentially heated by the heating effect of the heat transfer plate 22, the raw material gas is transferred to the raw material hydrogen between the inlet and the outlet of the reforming unit 8. As reforming progresses, the system can be made more efficient by improving reforming efficiency.

  Further, the surface of the heat transfer plate 22 is configured to be uneven by pressing or molding, thereby expanding the heat transfer area and disturbing the flow of the raw material gas flowing near the heat transfer plate, thereby making the boundary layer thin. Therefore, the contact area between the catalyst and the heat transfer plate 22 can be further increased, and heat conduction from the combustor 5 of the heating unit to the heat transfer plate 22 can be promoted by the catalyst of the catalyst layer 12, so that the catalytic reaction By sufficiently supplying the necessary heat, it is possible to prevent deterioration of the efficient system and catalyst by improving the reforming efficiency and to improve the durability and reliability.

(Embodiment 2)
FIG. 3 shows a cross-sectional view of the reforming section in the hydrogen generator in the second embodiment of the present invention. The difference from the first embodiment is that the heat transfer plate 22 is provided with an auxiliary heat transfer plate 23 that is convex on the surface of the heat transfer plate 22, and the thickness of the auxiliary heat transfer plate 23 is the plate of the heat transfer plate 22. It is made thinner than the thickness. In this embodiment, the auxiliary heat transfer plate 23 has a cylindrical shape and is in close contact with each of the heat transfer plates 22. And the catalyst container 11 wall surface of the reforming part 8 which contacted the combustor 5 which is a heating means, and the heat-transfer plate 22 are comprised integrally using the extrusion molding material. In this embodiment, the catalyst container 11, the heat transfer plate 22, and the auxiliary heat transfer plate 23 are formed in a cylindrical shape by an integral extruded material, and the upper and lower portions are attached with separate members.

  Thus, the heat transfer plate 22 is provided with a convex auxiliary heat transfer plate 23 on the surface thereof, and the thickness of the auxiliary heat transfer plate 23 is made thinner than the plate thickness of the heat transfer plate 22. The flow resistance of the raw material gas flowing through the catalyst layer 12 in the catalyst container 11 is not increased. Part of the heat flowing through the heat transfer plate 22 is radiated to the catalyst layer 12, and the remaining heat flows to the auxiliary heat transfer plate 23. Therefore, even if the plate thickness of the auxiliary heat transfer plate 23 is made thinner than the plate thickness of the heat transfer plate 22 due to the heat flow rate, the amount of heat does not decrease. When the auxiliary heat transfer plate 23 is thickened, the flow resistance increases by reducing the cross-sectional area of the catalyst layer 12 through which the raw material gas flows. In addition, the contact area between the catalyst of the catalyst layer 12 and the heat transfer plate 22 can be remarkably increased by adding the contact area of the auxiliary heat transfer plate 23, so that the combustor 5 serving as a heating unit can be changed to the heat transfer plate 22. Heat conduction can be promoted by the catalyst using the catalyst, sufficient heat for the catalysis reaction can be supplied, and efficient system and improvement of the reforming efficiency can be prevented and deterioration of the catalyst can be prevented, resulting in high durability and reliability. .

  Further, the wall surface of the catalyst container 11 and the heat transfer plate 22 of the reforming section 8 in contact with the combustor 5 serving as a heating means are integrally formed using an extrusion molding material or the like. The plate 22 is configured to have a low thermal resistance generated in the contact portion, and heat from the combustor 5 can be conducted to the heat transfer plate 22 without lowering the temperature, can accelerate the heating of the catalyst, and sufficiently supplies the heat necessary for the catalytic reaction. Thus, the reforming efficiency is improved and the system becomes more efficient. Also, the integral molding of the wall surface of the reforming section 8 and the heat transfer plate 22 improves the adhesion reliability, reduces the number of parts, and reduces the number of assembly steps. Thus, the cost can be reduced by simplifying the configuration.

  As described above, the hydrogen generator according to the present invention constitutes the heat transfer plate that protrudes inside the reforming section, so that the heat generated in the heating section is heat transfer plate that protrudes inside the reforming section. Heat can be transferred to the entire catalyst in the reforming section, and the amount of heat necessary for the reaction can be constantly supplied to the endothermic reaction performance to ensure sufficient performance, and the entire catalyst can react uniformly. It can prevent partial overheating and local reaction, and can provide an efficient system and catalyst deterioration due to improved reforming efficiency to provide a highly durable hydrogen generator, suitable for applications such as fuel cell hydrogen sources it can.

1 is a longitudinal sectional view of a reforming section in a hydrogen generator in Embodiment 1 of the present invention. Cross-sectional view of the reforming section in the hydrogen generator in Embodiment 1 of the present invention Cross-sectional view of the reforming section in the hydrogen generator in Embodiment 2 of the present invention Block diagram showing everything from raw material supply using steam reformer, steam supply to hydrogen gas outlet Sectional view of the reforming section in a conventional hydrogen generator

Explanation of symbols

DESCRIPTION OF SYMBOLS 5 Combustor 8 Reforming part 9 Raw material supply means 10 Water supply means 11 Catalyst container 12 Catalyst layer 21 Product gas outlet 22 Heat transfer plate 23 Auxiliary heat transfer plate

Claims (6)

A means for supplying a raw material, a means for supplying water, a heating means, a reforming section filled with a catalyst, a CO conversion section, and a CO removal section are sequentially connected, and the contact section between the heating means and the reforming section. The hydrogen generator is characterized in that a heat transfer plate protruding inside the reforming section is formed. The hydrogen generator according to claim 1, wherein a plurality of heat transfer plates are configured in the reforming section at approximately equal intervals. The hydrogen generator according to claim 1, wherein the heat transfer plate is configured to protrude in parallel with a flow direction of the raw material gas flowing in the catalyst in the reforming section. The hydrogen generator according to any one of claims 1 to 3, wherein the heat transfer plate is configured such that a surface thereof is uneven. The heat transfer plate is provided with an auxiliary heat transfer plate that is convex on the surface thereof, and the thickness of the auxiliary heat transfer plate is made thinner than the plate thickness of the heat transfer plate. The hydrogen generator described in 1. The hydrogen generator according to any one of claims 1 to 5, wherein a wall surface of the reforming portion in contact with the heating means and a heat transfer plate are integrally formed using an extrusion molding material or the like.

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