JP2009161370A - Fuel reforming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel reforming apparatus that can quickly respond when starting the apparatus and rapidly increase the temperature of a catalyst layer to a predetermined temperature appropriate to a catalytic reaction. <P>SOLUTION: The fuel reforming apparatus includes a reforming catalyst, a carbon monoxide modifying catalyst, and a carbon monoxide removing catalyst, and heats these catalysts mainly by a combustion exhaust gas, in which an oxidation heat generating agent 35 that can return to the original state by reduction is disposed at a position adjacent to at least one of the reforming catalyst, the carbon monoxide modifying catalyst and the carbon monoxide removing catalyst, so as to auxiliary heat the at least one of the catalysts with the oxidation heat generating agent 35. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel reformer used in a fuel cell system.

  Conventionally, a resistance electric heater has been provided as a heat source or combustion exhaust gas has been used in order to quickly raise and activate the temperature of the catalyst of the fuel reformer. When a resistance electric heater is used as a heat source, temperature control is easy, but the efficiency of the entire system is reduced due to power consumption. In addition, when using combustion exhaust gas as a heat source, it is difficult to arrange a means for adjusting the flow rate of combustion exhaust gas in a structure at a high temperature, so control of the catalyst temperature is strongly influenced by the structure and operating conditions. It was.

  Basic heat transfer modes for heating the catalyst include heat conduction, heat convection and heat radiation. The catalyst heating method of a fuel reformer that is generally used often uses an electric heater, electromagnetic induction heating, direct or indirect heat conduction or heat convection using combustion exhaust gas as a heat source or heat medium. . When an electric heater is used, the catalyst temperature can be accurately controlled and the temperature controllability is excellent. However, since the electric power is consumed, the efficiency of the fuel cell system is reduced.

  Patent Document 1 describes a fuel reformer (hydrogen generator) that heats a catalyst by electromagnetic induction heating, and heats the inside of a reactor that generates hydrogen gas from a raw material containing a hydrocarbon compound by thermal decomposition. Therefore, a heating element disposed inside the reactor (having a function as a catalyst for thermally decomposing hydrocarbon compounds to generate hydrogen gas), and a heating element disposed outside the reactor, induction heating the heating element The structure provided with the induction heating means which consists of a drive means (induction heating coil) is disclosed.

  However, in the fuel reformer disclosed in Patent Document 1, in order to heat the heating element by induction heating, power must be supplied to the induction heating coil. As a result, the efficiency of the fuel cell system is reduced. In contrast to such a heating mode, a method using combustion exhaust gas can improve the efficiency of the entire system without power consumption for heating the catalyst.

In the fuel reformer disclosed in Patent Document 2 as a catalyst for heating the catalyst using such combustion exhaust gas, as shown in FIG. 5, a combustor 91 is disposed at the center (on the central axis). The steam generation unit 92 and the reforming unit 93 are arranged from the upper position outside the combustor 91 to the lower position, and the carbon monoxide conversion unit 94 and the carbon monoxide removal are further positioned above the reforming unit 93 outside. A combustion exhaust gas passage 91 is formed in the gap between the combustor 91, the steam generation unit 92, and the reforming unit 93. The high-temperature combustion exhaust gas discharged from the combustor 91 flows through the combustion exhaust gas passage 91, and the reforming section 93, the carbon monoxide shift section 94, and the carbon monoxide removal section 95 are heated by the heat of the combustion exhaust gas. As a result, the temperature is maintained at a predetermined temperature suitable for the reaction of the catalyst layers (the reforming portion, the carbon monoxide shift catalyst layer, and the carbon monoxide removal catalyst layer) disposed in each of the components 93 to 95. It is configured.
JP 2003-206102 A JP 2007-057892 A

  In the fuel reformer disclosed in Patent Document 2, fuel off-gas discharged without being used for reaction from the fuel cell is supplied as burner fuel during normal operation, and is also used for reforming at startup. The hydrocarbon-based fuel gas is supplied and burned in the combustor 91. Thus, unlike the fuel reformer disclosed in Patent Document 1, it is not necessary to supply electric power to the electric heater or the induction heating coil, and the efficiency of the fuel cell system can be prevented from decreasing.

  However, since the carbon monoxide conversion unit 94 and the carbon monoxide removal unit 95 are heated via the water vapor generation unit 92, even if the fuel gas is burned in the combustor 91 at the time of start-up, the water vapor generation unit 92 is rapidly produced. Even when the temperature is increased by heating the reforming section 93, the carbon monoxide conversion section 94, or the carbon monoxide removal section 95, the carbon oxide conversion section 94 and the carbon monoxide removal section 95 are heated at the temperature of the water vapor generation section 92. Since it is directly affected and cannot exchange heat directly with the flue gas flowing through the flue gas passage 91, it takes a long time to maintain the temperature of each catalyst layer at a predetermined temperature suitable for the reaction there. Become. That is, there has been a problem that it is impossible to respond quickly at the time of startup.

  The present invention has been made in view of the problems as described above. With a simple configuration and operation, the temperature of the catalyst layer is maintained at a predetermined temperature suitable for the catalytic reaction by quickly responding to the start-up. An object of the present invention is to provide a fuel reformer that can perform the above-described process.

  In order to solve the above-mentioned problems, the present invention includes a reforming catalyst, a carbon monoxide conversion catalyst, and a carbon monoxide removal catalyst. In a fuel reformer that mainly heats these with combustion exhaust gas, the reforming catalyst, carbon monoxide conversion An oxidation exothermic agent that can return to its original state upon reduction is disposed at a position adjacent to at least one of the catalyst and the carbon monoxide removal catalyst, and the oxidation exothermic agent assists the at least one catalyst. It is characterized by heating.

  According to the fuel reformer of the present invention, at least one of the reforming catalyst, the carbon monoxide conversion catalyst, and the carbon monoxide removal catalyst is auxiliary-heated by the oxidation exothermic agent disposed in the adjacent position, In addition, since this exothermic agent has a property of rapidly generating heat by supplying oxygen, at the time of starting the fuel reformer, at least one of the reforming catalyst, the carbon monoxide conversion catalyst, and the carbon monoxide removal catalyst is used. The temperature can be quickly raised to an appropriate temperature, and the full operation start time of the apparatus can be shortened. As a result, the operation efficiency of the apparatus can be improved.

  In the present invention, if the oxidation exothermic agent is configured to be reduced by a part of the reformed and generated hydrogen gas, it is not necessary to provide a special hydrogen supply means, so that the structure of the apparatus is not complicated, Is preferred.

  Moreover, when the said oxidation heat generating agent is a catalyst agent containing copper and zinc, the rapid heating performance at the time of oxidation is excellent and suitable.

  According to the fuel reformer of the present invention, at the start of the fuel reformer, the temperature of at least one of the reforming catalyst, the carbon monoxide conversion catalyst, and the carbon monoxide removal catalyst is quickly raised to an appropriate temperature. And the operating efficiency of the apparatus can be improved.

  The fuel reformer according to the first embodiment of the present invention shown in FIG. 1 has the same axial center with the inner heating cylinder 1, reaction cylinder 2, outer heating cylinder 3, and outer cylinder 4 from the center side toward the outer peripheral side. Have on.

  The inside of the top and bottom cylindrical inner heating cylinder 1 formed in the center of the fuel reformer is defined as an inner / outer double structure by a partition wall 5, and a combustion provided with a burner 6 on the inner peripheral side. It becomes the chamber 7, and the outer peripheral side is a combustion gas discharge space 8. The combustion chamber 7 has a bottom plate 10 having a gas circulation port 9, and a gas circulation space 12 is formed between the bottom plate 10 and the bottom plate 11 of the inner heating cylinder 1. Connected to the burner 6 is an off-gas supply pipe 13 that passes through the top plate 16 of the combustion chamber 7 and is introduced into the burner 6. A main portion 14 a of an air supply pipe 14 is connected to an air intake port 17 provided in the top plate 16, and a combustion gas discharge pipe 15 is provided at an upper end portion, that is, a downstream end portion of the combustion gas discharge space 8. It is connected.

  An annular annular space in the reaction cylinder 2 located on the outer peripheral side of the inner heating cylinder 1 is partitioned into an inner annular space 19 and an outer annular space 20 by a partition wall 18 except for a lower end space 28 thereof. ing. The bottom plate 21 of the reaction tube 2 is flush with the bottom plate 11 of the inner heating tube 1. A source gas supply pipe 22 is connected to the upper end of the inner annular space 19. A generated gas take-out pipe 29 is connected to the upper end of the outer annular space 20.

  The upper part of the inner annular space 19 is a water vapor generating part 23, and the lower part is a reforming part 24. The lower part of the outer annular space 20 is a gas passage space 25, the middle height part is a carbon monoxide conversion part 26, and the upper part is a carbon monoxide removal part 27.

  A bottomed cylindrical outer heating cylinder 3 disposed so as to surround the side periphery and bottom of the reaction cylinder 2 has an annular side peripheral space 30 on the outer periphery of the reaction cylinder 2, and the bottom plate 29 and the A lower space 31 is formed between the bottom plates 11 and 21. An air supply branch pipe 32 and a heated gas exhaust pipe 33 are connected to the side peripheral space 30. Further, a generated gas return pipe 34 is connected to the upper end portion of the side circumferential space 30. A heat generating agent (oxidation catalyst) 35 is filled in the side circumferential space 30 and the lower space 31 of the outer heating cylinder 3.

  The outer heating cylinder 3 is arranged so that the entire periphery is surrounded by the outer cylinder 4. The outer cylinder 4 has a cylindrical shape having a side peripheral wall 36, a top plate 37, and a bottom plate 38. The space between the side peripheral wall 39 and bottom plate 29 of the outer heating cylinder 3 and the side peripheral wall 36 and bottom plate 38 of the outer cylinder 4, and the top and outer cylinders of the outer heating cylinder 3, the reaction cylinder 2, and the inner heating cylinder 1 A space between the top plate 37 and the top plate 37 is filled with a heat insulating material 40.

  A base end of the off gas supply pipe 13 is connected to an off gas generation unit 42 of the fuel cell 41. A first flow path switching valve 43 is disposed in the middle of the off gas supply pipe 13. The tip of the product gas take-out pipe 29 is connected to the product gas supply unit 44 of the fuel cell 2. In the middle of the product gas take-out pipe 29, a second flow path switching valve 45 is disposed upstream and a third flow path switching valve 46 is disposed downstream.

  An activation gas supply pipe 47 is connected to the first flow path switching valve 43. The first flow path switching valve 43 and the third flow path switching valve 46 are connected by a bypass pipe 48. Further, the base end of the product gas return pipe 34 is connected to the second flow path switching valve 45. The proximal end of the air supply officer 14 is connected to the combustion air supply means 51, and a fourth flow path switching valve 52 is provided in the middle. The fourth flow path switching valve 52 is connected to the air supply main part 14 a connected to the air intake port 17 and the air supply branch pipe 32. A combustion gas discharge means 53 is connected to the tip of the combustion gas discharge pipe 15, and a first flow rate adjustment valve 54 is arranged on the way. A heated gas exhaust means 55 is connected to the tip of the heated gas discharge pipe 33, and a second flow rate adjusting valve 56 is arranged in the middle.

  In FIG. 1, 49 is an air introduction pipe of the fuel cell 41, and 50 is an air discharge pipe of the fuel cell 41. Reference numerals 57, 58, and 59 denote temperature sensors that measure the temperatures of the reforming unit 24, the carbon monoxide conversion unit 26, and the carbon monoxide removal unit 27, respectively.

  The steam generation unit 23 heats a hydrocarbon-based source gas (specifically, city gas 13A) and water supplied from the source gas supply pipe 22 to generate a steam-added gas.

  The reforming unit 24 includes a reforming catalyst layer, and reforms a hydrocarbon gas (for example, methane gas) in a raw material gas by passing the steam-added gas through the reforming catalyst layer, and converts carbon monoxide into a reformed catalyst layer. A reforming gas rich in hydrogen is produced. As the reforming catalyst, a ruthenium-based steam reforming catalyst is used. Instead of this, a nickel-based steam reforming catalyst or the like may be used. The reforming reaction of hydrocarbon gas is an endothermic reaction.

  The carbon monoxide shift section 26 includes a carbon monoxide shift catalyst layer, and the concentration of carbon monoxide in the reformed gas is 1% or less by passing the reformed gas through the carbon monoxide shift catalyst layer. It is to make. A copper-zinc catalyst is used as the carbon monoxide conversion catalyst. Instead of this, a noble metal catalyst may be used. Note that the carbon monoxide shift reaction is an exothermic reaction.

  The carbon monoxide removal unit 27 includes a carbon monoxide removal catalyst layer, and allows the reformed gas having a carbon monoxide concentration of 1% or less to pass through the monoxide removal catalyst layer to selectively select carbon monoxide. The carbon dioxide gas is oxidized to obtain a reformed gas having a carbon monoxide concentration of 10 ppm or less. A noble metal catalyst is used as the carbon monoxide removal catalyst. Note that the carbon monoxide removal reaction is an exothermic reaction.

  As the exothermic agent 35, the same substance as the copper-zinc catalyst used as the carbon monoxide shift catalyst is used. This exothermic agent 35 has a property that it can generate oxidation heat when given oxygen even at low temperatures and can be reduced to its original state when given hydrogen. That is, it is a reversible low temperature oxidation exothermic exothermic agent.

  The water-added raw material gas is supplied into the reaction tube 2 from the raw material supply pipe 22, and is supplied with a steam generation unit 23, a reforming unit 24, a lower end space 28, a gas passage space 25, a carbon monoxide conversion unit 26, While passing through the carbon monoxide removal unit 27, the gas is reformed as described above, and is taken out as a reformed gas (product gas) having a carbon monoxide concentration of 10 ppm or less to the product gas take-out pipe 29. The product gas contains carbon dioxide, water vapor, and carbon monoxide of 10 ppm or less in addition to hydrogen.

  In order for the source gas to be reformed efficiently and satisfactorily, the temperature of each catalyst layer must be maintained appropriately. Therefore, the reforming catalyst layer is heated to 600 to 700 ° C., the carbon monoxide shift catalyst layer is heated to 250 to 350 ° C., and the carbon monoxide removal catalyst layer is heated to a range of 110 to 250 ° C. and maintained in that temperature range. It is hoped that The inner heating cylinder 1 and the outer heating cylinder 3 are provided as means for heating these catalyst layers.

  Off gas (hydrogen, water vapor) from the off gas generating part 42 of the fuel cell 41 is supplied to the inner heating cylinder 1 through the off gas supply pipe 13. And it burns with the burner 6 in the combustion chamber 7, The combustion gas flows in into the gas distribution space 12 from the said gas distribution port 9, then changes direction upwards, raises the combustion gas discharge space 8, and discharges combustion gas It is discharged from the tube 15 to the outside. Since the off gas cannot be used when starting the apparatus, the first switching valve 43 is switched to introduce the city gas supplied from the starting gas supply pipe 47 into the off gas supply pipe 13 and burn it in the burner 6. Like to do.

  The combustion gas mainly heats the steam generation unit 23, the reforming unit 24, the carbon monoxide conversion unit 26, and the carbon monoxide removal unit 27. In particular, the steam generation part 23 and the reforming part 24 arranged so as to be in contact with the combustion gas discharge space 8 are effectively heated.

  Air necessary for the combustion of the burner 6 is supplied from the combustion air supply means 51, and passes through the air supply pipe 14, the fourth flow path switching valve 52, and the air supply pipe main portion 14 a from the air intake port 17 through the combustion chamber 7. Is taken in. The fourth flow path switching valve 52 has a flow rate adjustment function and can adjust the amount of air supplied to the combustion chamber 7 and the amount of air supplied to the outer heating cylinder 3 described later.

  When the apparatus is started, the fourth flow path switching valve 52 sends air to the air supply main pipe 14a and simultaneously sends air to the air supply branch pipe 32 to oxidize the heat generating agent 35 in the outer heating cylinder 3. It is configured to generate heat. The air used for the oxidation heat generation is sucked into the heated gas discharge means 55 and discharged from the heated gas exhaust pipe 33 to the outside.

  The steam generation unit 23, the reforming unit 24, the carbon monoxide conversion unit 26, and the carbon monoxide removal unit 27 are auxiliary-heated by the oxidation heat generated by the heat generating agent 35. In particular, the reforming unit 24, the carbon monoxide conversion unit 26, and the carbon monoxide removal unit 27 disposed so as to be in contact with the side circumferential space 30 filled with the heat generating agent 35 are effectively auxiliary-heated.

  Heating by the heat generating agent 35 is for raising the temperature of the reforming unit 24, the carbon monoxide conversion unit 26, and the carbon monoxide removal unit 27 to a predetermined appropriate temperature in a short time when the apparatus is started. After 20 minutes, the flow path of the fourth flow path switching valve 52 is selected, air is supplied to the outer heating cylinder 3, and the heat generating agent 35 is caused to generate heat by oxidation. Thereafter, the flow path of the fourth flow path switching valve 52 is switched, the supply of air to the outer heating cylinder 3 is stopped, and the heating by the heat generating agent 35 is stopped.

  The heating by the heat generating agent 35 is controlled by adjusting the amount of air supplied to the heat generating agent 35 by the flow rate adjusting function of the fourth flow path switching valve 52 or the second flow rate adjusting valve 56 arranged in the heated gas exhaust pipe 33. This can be done by adjusting the amount of discharged air by the flow rate adjusting function.

  The exothermic agent 35 stops its heat generation when oxygen is saturated, but about 20 minutes is appropriate as a time for continuously generating heat efficiently. In order to use it again for heat generation, it is necessary to reduce it by supplying hydrogen. For this reason, by switching the flow path of the second flow path switching valve 45, a part of the generated gas is led from the generated gas take-out pipe 29 to the generated gas return pipe 34, and is transferred to the heat generating agent 35 in the outer heating cylinder 3. Hydrogen in the product gas is given. The reduction of the heat generating agent 35 takes a relatively long time. For example, it is necessary to return a part of the generated gas to the heat generating agent 35 for about 4 hours. Note that the reduction state of the heat generating agent 35 may be detected by a sensor, and the return of the generated gas may be stopped when the reduction is completed.

  The second flow path switching valve 45 is in a first state in which the entire amount of the product gas flows to the downstream side of the product gas extraction pipe 29, and the product gas is supplied to the downstream side of the product gas extraction pipe 29 and the product gas return pipe 34. And a third state in which the total amount of the product gas is allowed to flow through the product gas return pipe 34, and a function of adjusting the respective flow rates.

  The temperature control of each catalyst layer is performed according to the detection signals from the temperature sensors 57, 58, 59, the combustion gas discharge amount by the first and second flow rate adjusting valves 54, 56, and the fourth flow path switching valve 52, heating This is done by adjusting the amount of gas discharged and the amount of combustion air.

  At the time of starting the apparatus, the temperature of each catalyst layer has not risen to an appropriate temperature. First, the city gas from the starting gas supply pipe 47 is introduced into the inner heating cylinder 1 and burned by the burner 6 and air. Each catalyst is heated and heated by introducing air from the supply branch pipe 32 into the outer heating cylinder 3 and causing the heat generating agent 35 to generate heat by oxidation. The first 20 minutes is the first step for heating the catalyst in this way. In particular, the carbon monoxide shift section 26 and the carbon monoxide removal section 27 can be rapidly heated by the auxiliary superheating by the heat generating agent 35 in this step.

  For the next 20 minutes, the city gas from the starting gas supply pipe 47 is continuously introduced into the inner heating cylinder 1 and burned by the burner 6, but the supply of air from the air supply branch pipe 32 is continued. And the second step of stopping heating by the heat generating agent 35. By this step, the temperature of each catalyst can be further increased.

  For the next 20 minutes, with the combustion of the burner 6 continued, a raw material gas to which water has been added is supplied from the raw material gas supply pipe 22 to generate a generated gas. This generated gas is supplied to the fuel cell 41. The third process is not supplied. In this step, since the temperature of each catalyst has not yet risen to an appropriate temperature and its catalytic function is insufficient, the concentration of carbon monoxide in the product gas has not dropped to the specified value, and this is supplied to the fuel cell 41. If it is supplied, the battery performance may be deteriorated. Therefore, the third flow path switching valve 46 and the first flow path switching valve 43 are set to predetermined switching positions, and the third gas switching pipe 29 is configured to perform the third flow switching. The produced gas sent to the flow path switching valve 46 is caused to flow to the bypass pipe 48, then sent to the downstream side of the off-gas supply pipe 13 through the first flow path switching valve 43, and burned by the burner 6. I have to. The first flow path switching valve 43 is also configured to send the city gas from the starting gas supply pipe 47 to the burner 6 as necessary.

  After the preparation period of the first to third steps, the fourth step of full-scale operation is entered. In this step, the temperature of each catalyst is properly maintained, and the product gas is supplied to the fuel cell 41. Further, off-gas (hydrogen, water vapor) is generated from the fuel cell 41 and can be supplied from the off-gas generation unit 42 to the off-gas supply pipe 13. For this reason, the third flow path switching valve 46 and the first flow path switching valve 43 are respectively switched, and the generated gas sent from the generated gas take-out pipe 29 to the third flow path switching valve 46 is converted into fuel. Only the generated gas supply unit 44 of the battery 41 flows and only the off gas from the off gas generation unit 42 can be supplied to the burner 6 through the first flow path switching valve 43. In this step, the exothermic agent 35 is reduced using a part of the generated gas. For this reason, by switching the flow path of the second flow path switching valve 45, a part of the generated gas is led from the generated gas take-out pipe 29 to the generated gas return pipe 34, and is transferred to the heat generating agent 35 in the outer heating cylinder 3. Hydrogen in the product gas is given. This process is set to a length of about 8 hours in consideration of the reduction of the heat generating agent 35.

  The next fifth step is a step that continues until the apparatus is stopped. Since the reduction of the heat generating agent 35 is completed in the fourth step, it is not necessary to return the generated gas to the generated gas return pipe 34, and the second switching valve 45 is switched so as to enable this. Other states are the same as in the fourth step. Therefore, the raw material gas supplied from the raw material supply pipe 22 is reformed while passing through the reaction tube 2 to become a product gas, and the entire amount thereof is sent to the product gas supply unit 44 of the fuel cell 41.

As the exothermic agent 35, a composite or simple substance of the following compositions a and b can be used.
a CuO or Cu (copper)
b ZnO or Zn (zinc)
In addition, simple substances of the following compositions c, d, e, and f or composites in which these are appropriately combined can be used as the heat generating agent 35.
c CeO2 or Ce (cerium)
d ZrO2 or Zr (zirconia)
e Mn2O3 or Mn (manganese)
f Fe2O3 or Fe (iron)
In order to reduce the exothermic agent 35, the above embodiment uses a part of the product gas. Instead, hydrogen can be supplied to the exothermic agent 35 from a hydrogen supply means such as a hydrogen cylinder. Also good.

  FIG. 2 shows a second embodiment of the present invention. The difference from the first embodiment is that the outer heating cylinder 3 is formed so as to surround the lower part of the reaction cylinder 2, the side circumferential space 30 is short, and the reforming of the reforming section 24 is performed. This is a point in which only the catalyst is auxiliary-heated by the oxidation exothermic agent 35. In this embodiment, the outer heating cylinder 3 has a side circumferential space 30 and a lower space 31, and the space is filled with the oxidizing exothermic agent.

  FIG. 3 shows a third embodiment of the present invention. The difference from the first embodiment is that the outer heating cylinder 3 is formed so as to surround the intermediate height portion of the reaction cylinder 2 and has a bottomed, top-like annular body having only the side circumferential space 30. This is the point. In this embodiment, only the carbon monoxide conversion catalyst of the carbon monoxide conversion section 26 is auxiliary-heated by the oxidizing exothermic agent 35 filled in the side circumferential space 30.

  FIG. 4 shows a fourth embodiment of the present invention. The difference from the first embodiment is that the outer heating cylinder 3 is formed so as to surround the periphery of the upper part of the reaction cylinder 2, and has a bottomed and topped annular body having only the side circumferential space 30. It is a point. In this embodiment, only the carbon monoxide removal catalyst of the carbon monoxide removal unit 27 is auxiliary-heated by the oxidizing exothermic agent 35 filled in the side circumferential space 30.

1 is a cross-sectional view schematically showing the structure of a fuel reformer according to a first embodiment of the present invention. It is sectional drawing which shows typically the structure of the fuel reformer which concerns on 2nd Example of this invention. It is sectional drawing which shows typically the structure of the fuel reformer which concerns on 3rd Example of this invention. It is sectional drawing which shows typically the structure of the fuel reformer which concerns on 4th Example of this invention. It is sectional drawing which shows the structure of the fuel reformer which concerns on a prior art example typically.

Explanation of symbols

7 Combustion chamber 24 Reforming unit 26 Carbon monoxide conversion unit 27 Carbon monoxide removal unit 35 Oxidation exothermic agent

Claims (3)

  In a fuel reformer having a reforming catalyst, a carbon monoxide conversion catalyst, and a carbon monoxide removal catalyst, and mainly heating them with combustion exhaust gas, the reforming catalyst, the carbon monoxide conversion catalyst, and the carbon monoxide removal catalyst are included. An oxidation exothermic agent that can be returned to its original state by being reduced is disposed at a position adjacent to at least one catalyst, and the at least one catalyst is auxiliary-heated with the oxidation exothermic agent. apparatus.   The fuel reformer according to claim 1, wherein the oxidizing exothermic agent is configured to be reduced by a part of the reformed hydrogen gas.   The fuel reformer according to claim 1 or 2, wherein the oxidizing exothermic agent is a composite containing copper and zinc.

Images