JP2006294464A - Fuel cell power generation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve energy efficiency of a power generation system while improving the concentration of hydrogen produced from a hydrogen production device without increasing the size of the device nor generating an unnecessary reaction. <P>SOLUTION: This fuel cell power generation system is composed by including a hydrogen production device body 2a for producing a reform gas containing hydrogen by a reform reaction by an incorporated reform catalyst 6 by using a city gas, air and water or steam as a material; a polymer electrolyte fuel cell 1 for generating power by using the produced reform gas as a fuel; and a heat recovery unit 3 for recovering heat by burning an anode exhaust gas of the fuel cell 1. The heat recovery unit 3 is provided with a heat exchanger (reform catalyst) 12 having a heating object fluid passage filled with a granular reform catalyst 23; the city gas and water or steam are supplied to the heating object fluid passage; the heating object fluid passage is heated by combustion heat of the anode exhaust gas; and a material supply tube 42 for guiding a fluid having passed the heating object fluid passage to the hydrogen production device body 2a is provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel cell power generation system, and more particularly to an improvement in the efficiency of a hydrogen production apparatus that supplies a reformed gas rich in hydrogen to a fuel cell.

  BACKGROUND ART A fuel cell, for example, a polymer electrolyte fuel cell (hereinafter referred to as PEFC) used in a household fuel cell power generation system generates power using hydrogen and oxygen as fuel. In order to supply hydrogen to the PEFC, a hydrogen production apparatus that generates a gas containing hydrogen (hereinafter referred to as a reformed gas) from a hydrocarbon fuel such as city gas, kerosene, or LPG is required. In PEFC, 70 to 80% of the supplied hydrogen is used, but the remaining 20 to 30% is discharged as exhaust gas. Therefore, the remaining hydrogen is burned in a heat recovery device that forms a part of the hydrogen production apparatus. Heat recovery.

  Next, conventional configurations of the hydrogen production apparatus and the heat recovery unit will be described. The hydrogen production device includes a hydrogen production device main body (reformed gas generation means) and a heat recovery device, a pipe connecting the two, a hydrogen production device main body and a means for supplying various fluids to the heat recovery device, and a control device. Composed. From the lower part of the main body of the hydrogen production apparatus, hydrocarbon-based fuel (for example, city gas), air, and water (steam) as raw materials are supplied to the raw material mixing section, and the mixed gas is guided to the combustion catalyst. Here, city gas and air in the raw material react to generate heat. The exothermic gas is then guided to the reforming catalyst, where hydrogen is generated by an endothermic reaction in which the city gas and water vapor react. At this time, since a large amount of heat is required, the heat generated by the preceding combustion catalyst is used.

  The reaction at this time is shown in Formula (1), and carbon monoxide (hereinafter referred to as CO) is generated simultaneously with hydrogen. The generated hydrogen and CO-containing gas is called a reformed gas.

CH ₄ + H ₂ O → 3H ₂ + CO (1)
In the PEFC that generates power using hydrogen as the fuel, the performance is reduced by this CO, so the CO concentration must be reduced to 10 ppm or less. Therefore, a CO converter, a CO remover, etc. are generally used.

  In PEFC, after generating electricity using the above reformed gas, anode exhaust gas containing 20 to 30% hydrogen is released. The anode exhaust gas is combusted in the heat recovery unit, and the combustion heat is used for steam generation and preheating of raw materials (city gas, air, etc.).

  The heat recovery unit is composed of a starter burner, a combustion catalyst, and a plurality of heat exchangers through which water, air, and city gas respectively flow. The anode exhaust gas discharged from the PEFC is burned by the combustion catalyst, and the heat is used to The raw material is preheated by a plurality of heat exchangers.

  Patent Document 1 discloses a system in which a preliminary reformer is installed on the upstream side of the main reformer. In Patent Document 2, a pre-reformer is installed in the reformer, and a part of the mixed gas of the raw material and steam charged in the reformer is converted into hydrogen in the pre-reformer, and the remaining in the catalyst layer Have been disclosed which convert to hydrogen. Further, in Patent Document 3, a first reaction chamber filled with a steam reforming catalyst layer is installed upstream of a second reaction chamber filled with a mixed catalyst layer in which a steam reforming catalyst and an oxidation catalyst are mixed. A configuration is disclosed in which a raw material-steam mixture charged in a reformer is reformed in a second reaction chamber.

JP-A-11-292503 (first page, FIG. 1) JP 2001-031403 A (1st, 2nd page, FIG. 1) JP 2004-137108 A (6th, 9th, 10th pages, FIG. 3)

  In the above-described conventional technology, there is a problem that the effective use of heat generated in the heat recovery device is not sufficiently considered, and usable heat is released. In addition, there is a problem that the hydrogen concentration generated from the hydrogen production apparatus is low.

In order to effectively use the heat generated in the heat recovery unit, a method of increasing the heat transfer efficiency of the heat exchanger installed in the heat recovery unit and increasing the amount of heat supplied to the raw material can be considered. In order to increase the efficiency of the heat exchanger, it is necessary to increase the heat transfer area, resulting in a larger device.
(2) When the amount of heat supply to the raw material is increased, unnecessary reactions such as thermal decomposition of the raw material (CH ₄ → C + 2H ₂ etc.) occur.
There were problems such as.

  Although the thing of the said patent documents 1-3 differs from the said prior art by the point which performs reforming in two places, it does not consider about the effective utilization of the heat | fever of a heat recovery device.

  An object of the present invention is to improve the energy efficiency of a power generation system without increasing the size of the apparatus and causing unnecessary reactions, and at the same time, is generated from a hydrogen production apparatus comprising a reformed gas generation means and a heat recovery device. It is to improve the hydrogen concentration.

  The above-described object is achieved by using the heat generated in the heat recovery device as a heat source for heat necessary for performing the reforming reaction, not simply for preheating the raw material gas.

  Specifically, the above-mentioned problem is a reformed gas generating means for generating a reformed gas containing hydrogen by a reforming reaction by a reforming catalyst using hydrocarbon fuel, oxygen or air and water or steam as raw materials, A fuel cell power generation system comprising: a fuel cell that generates electricity using the generated reformed gas as fuel; and a heat recovery unit that recovers heat by burning the anode exhaust gas of the fuel cell, wherein the heat recovery unit A heat exchanger including a heated fluid channel filled with a reforming catalyst, a means for supplying hydrocarbon fuel and water or steam to the heated fluid channel, and the heated fluid And a conduit that guides the fluid that has passed through the flow path to the reformed gas generation means.

  According to the above configuration, the anode exhaust gas is combusted in the heat recovery unit, and the hydrocarbon-based fuel and water or water vapor are supplied to the heated fluid passage filled with the reforming catalyst of the heat exchanger installed in the heat recovery unit. By supplying, the reforming reaction proceeds inside the heated fluid flow path, and a part of the injected hydrocarbon fuel is converted to hydrogen. Since the reforming reaction is an endothermic reaction, the combustion heat of the anode exhaust gas can be used effectively. That is, the efficiency of the heat exchanger can be improved without increasing the temperature of the raw material more than necessary and without changing the size of the heat exchanger.

  On the other hand, since a part of the hydrocarbon-based fuel charged in the heat exchanger is converted to hydrogen, the amount of reforming reaction is reduced in the reformed gas generating means as compared with the prior art. That is, since the amount of heat to be supplied can be reduced, the amount of air supplied as a heat source can be reduced, and the hydrogen concentration of the reformed gas sent out from the reformed gas generating means, in other words, generated by the hydrogen production apparatus. It is possible to increase the hydrogen concentration of the reformed gas.

  Further, a temperature measuring means for measuring the temperature of the reformed gas is provided at the reformed gas outlet of the reforming catalyst of the reformed gas generating means, and the measured value by the temperature measuring means falls within a predetermined temperature range. Thus, it is desirable to provide a controller for adjusting the amount of air supplied to the reformed gas generating means. By adjusting the amount of air supplied to the reforming catalyst in this way, the start-up time can be shortened and the hydrogen concentration of the reformed gas sent out from the reformed gas generating means during steady operation can be increased.

  An evaporator that evaporates water may be installed on the upstream side of the heating fluid channel of the heat exchanger, and the generated water vapor may be supplied to the heated fluid channel. By configuring in this way, the supplied water can be reliably evaporated and then supplied to the reforming catalyst filled in the heated fluid passage, so that the deterioration of the reforming catalyst due to water evaporation can be prevented. There is.

  The heated fluid channel may be provided with means for supplying air in addition to hydrocarbon fuel and water or water vapor. With fuel types such as LNG and kerosene, there is an effect that the reforming reaction can proceed stably by introducing a small amount of air into the reforming catalyst section.

  In addition, it is desirable that the combustion part to which the anode exhaust gas of the heat recovery unit is supplied is provided with means for supplying hydrocarbon fuel. If constituted in this way, at the time of start-up, the temperature of the reforming catalyst filled in the heated fluid flow path is increased by supplying hydrocarbon fuel to the combustion part to which the anode exhaust gas of the heat recovery device is supplied, The start of the reforming reaction by the reforming catalyst filled in the heated fluid channel can be promoted. The supply of the hydrocarbon-based fuel may be stopped when the anode exhaust gas is generated.

  In addition, at the time of start-up, the temperature of the reforming catalyst inside the heat exchanger installed in the heat recovery unit that burns the anode exhaust gas is not sufficient to perform the reforming reaction. Therefore, the amount of hydrogen generated from the heated fluid passage filled with the reforming catalyst in the heat exchanger in the heat recovery device is small. In this case, hydrogen is generated in the reforming catalyst section inside the reformed gas generating means. Specifically, the amount of partially oxidized air supplied to the reforming catalyst inside the reformed gas generating means is increased from the steady operation state, and the reforming reaction proceeds. This method makes it possible to generate hydrogen in a short time.

  According to the present invention, it is possible to reduce the amount of heat dissipated in the heat recovery unit without increasing the heat exchanger of the heat recovery unit and without causing thermal decomposition of the raw material. It is possible to improve the efficiency.

(First embodiment)
FIG. 1 shows a main configuration of the fuel cell power generation system according to the first embodiment of the present invention. In the present embodiment, an example in which city gas is used as fuel is shown, but the same applies to other hydrocarbon fuels such as LPG and kerosene.

  The illustrated fuel cell power generation system is connected to the hydrogen production apparatus 2, the reformed gas outlet of the hydrogen production apparatus 2, and connected to the reformed gas supply pipe 34 and the reformed gas supply pipe 34 with a valve 44 interposed therebetween. The polymer electrolyte fuel cell (hereinafter referred to as PEFC) 1, the air blower 20 connected to the PEFC 1 by the air supply pipe 36, the anode exhaust gas supply pipe 26 connected to the anode exhaust gas outlet of the PEFC 1, and the valve 44 upstream The reformed gas supply pipe 34 and the reformed gas bypass pipe 46 connecting the anode exhaust gas supply pipe 26 via a valve 45 are included.

  The hydrogen production apparatus 2 includes a hydrogen production apparatus main body 2a, which is a reformed gas generation means, and a heat recovery unit disposed at the downstream end of the anode exhaust gas supply pipe 26 by connecting the anode exhaust gas inlet of the startup burner 10 installed therein. 3, a city gas blower 16 for supplying city gas from below the activation burner 10, an air blower 15 for supplying air to the activation burner 10 through an air supply pipe 27, and a heat exchanger incorporated in the heat recovery unit 3. (Reforming catalyst) Heat exchange with a city gas blower 17 connected by a city gas supply pipe 24 to the heated fluid flow path entrance side of the reforming catalyst 12 and a water pump 18 connected by a water supply pipe 25 to the city gas supply pipe 24 A raw material supply pipe 42 for connecting the heated fluid flow path outlet side of the reactor (reforming catalyst) 12 and the hydrogen production apparatus main body 2a, an air blower 14 connected to the hydrogen production apparatus main body 2a by an air supply pipe 43, hydrogen Manufacturing The water pump 19 connected to the apparatus main body 2a by the water supply pipe 38, the water vapor supply pipe 39 connecting the hydrogen production apparatus main body 2a and the city gas supply pipe 24, and the gas temperature in the hydrogen production apparatus main body 2a are measured. A temperature measuring device 21 that is a temperature measuring means and a controller 22 that controls the air blower 14 by using the output of the temperature measuring device 21 as an input are configured.

  The hydrogen production apparatus main body 2a is supplied with a raw material mixing unit 4, a starting burner 9 connected to the raw material mixing unit 4, a combustion catalyst 5 disposed adjacent to the starting burner 9, and a gas that has passed through the combustion catalyst 5. The reforming catalyst 6 disposed at a position where the gas passes through the reforming catalyst 6, the heat exchanger 13 disposed at a position where the gas passing through the reforming catalyst 6 flows in, and the position where the gas passing through the heat exchanger 13 flows in. A CO converter 7 and a CO remover 8 that is disposed at a position where the gas that has passed through the CO converter 7 flows in and that has a reformed gas outlet on the outlet side are included.

  The hydrogen production apparatus main body 2a side of the water supply pipe 38 is connected to the heated fluid inlet side of the heat exchanger 13, and the hydrogen production apparatus main body 2a side of the water vapor supply pipe 39 is connected to the heated fluid outlet side of the heat exchanger 13. It is connected. Both the air supply pipe 43 and the raw material supply pipe 42 are connected to the raw material mixing unit 4 on the hydrogen production apparatus main body 2a side. Further, the measurement end of the temperature measuring device 21 is arranged to measure the gas temperature downstream of the reforming catalyst 6, and the controller 22 receives the temperature measured by the temperature measuring device 21 as an input. The flow rate of air supplied from the upstream of the reforming catalyst 6 is adjusted so that the temperature to be maintained is a constant temperature.

  The heat recovery unit 3 includes a starting burner 10 disposed in the lower part, a combustion catalyst 11 disposed above the starting burner 10, and a heat exchanger disposed above the combustion catalyst 11 and filled with the granular reforming catalyst 23. (Reforming catalyst) 12 is included.

  A specific structure of the heat exchanger (reforming catalyst) 12 is shown in FIG. A heat exchanger (reforming catalyst) 12 prepared by combining two pressed thin plates is provided with a heated fluid channel that snakes in a vertical plane, and a granular reforming catalyst 23 is provided below the heated fluid channel. Is filled. A city gas supply pipe 24 and a water supply pipe 25, which are raw materials, are connected to the heated fluid passage upper side entrance of the heat exchanger. The city gas supply pipe 24 is connected to the city gas blower 17 shown in FIG. The water supply pipe 25 is connected to the water pump 18 shown in FIG.

  The operation procedure of this embodiment is shown below.

  First, at the time of startup, in order to raise the temperature of the combustion catalyst 5 and the reforming catalyst 6, the city gas blower 16 and the air blower 15 are operated to supply city gas and air to the startup burner 9, and the startup burner 9 is ignited. . At the same time, the starting burner 10 is ignited to raise the temperature of the combustion catalyst 11 of the heat recovery unit 3.

  When the temperature of each of the combustion catalyst 5 and the combustion catalyst 11 reaches a predetermined temperature, the amount of air is increased and the combustion field is shifted to the combustion catalyst 5 and the combustion catalyst 11. Thereafter, water is supplied to each heat exchanger, and when each part reaches a predetermined temperature, the amount of city gas supplied to the heat exchanger (reforming catalyst) 12 is increased by the city gas blower 17 and the raw material is mixed by the air blower 14. The amount of air supplied to the unit 4 is decreased, and the condition shifts to a condition where hydrogen is generated in the reforming catalyst 6.

  At this time, since the reformed gas contains a small amount of carbon monoxide (CO) for a while after the transition to the hydrogen generation state, the valve 44 is closed and the valve 45 is opened for a predetermined time to bypass the PEFC 1 and The whole quantity of quality gas is returned to the heat recovery unit 3.

  At the same time as the reformed gas returns to the heat recovery unit 3, the amount of city gas supplied to the combustion catalyst 5 of the heat recovery unit 3 by the city gas blower 16 is reduced or stopped.

  At this time, the supplied water evaporates in the upper part of the heat exchanger (reforming catalyst) 12 of the heat recovery unit 3 to become steam and is mixed with the city gas, and then the heat exchanger (reforming catalyst) of the heat recovery unit 3. ) 12 is supplied to the granular reforming catalyst 23 filled in the lower part of the heated fluid flow path. Here, the granular reforming catalyst 23 is heated by the combustion heat from the combustion catalyst 11 installed in the lower part of the heat exchanger (reforming catalyst) 12. Due to this heat, part of the city gas and water vapor supplied to the granular reforming catalyst 23 proceeds with the following reaction to generate hydrogen.

CH ₄ + H ₂ O → 3H ₂ + CO
That is, at the outlet of the heat exchanger (reforming catalyst) 12 of the heat recovery unit 3, a reaction gas containing city gas, water vapor, hydrogen, and carbon monoxide is obtained, and this gas passes through the raw material supply pipe 42 and becomes hydrogen. It is supplied to the manufacturing apparatus main body 2a. This reaction gas is converted into a reformed gas containing more hydrogen by the reforming catalyst 6 inside the hydrogen production apparatus main body 2a. At this time, air is supplied by the air blower 14 in order to ensure the amount of heat necessary for the reforming reaction, and this air amount needs to be adjusted so that the temperature of the reforming catalyst 6 becomes a predetermined temperature. Therefore, the measuring end of the temperature measuring device 21 is installed at the outlet of the reforming catalyst 6, and the air flow rate of the air blower 14 is adjusted by the controller 22 so that the temperature becomes a predetermined temperature (580 to 620 ° C.).

At the time of start-up, since the temperature inside the heat recovery unit 3 is not sufficient for the action of the granular reforming catalyst 23, the granular reforming catalyst 23 installed inside the heat exchanger (reforming catalyst) 12 in the heat recovery unit 3. The hydrogen concentration in the reaction gas that passed through is low, and a large amount of city gas remains. For this reason, a large amount of heat is required to convert CH ₄ remaining in the reaction gas into H _2, and in order to secure this heat, the amount of air supplied to the hydrogen production apparatus main body 2a is made larger than a predetermined value. It is necessary to input.

  On the other hand, in the steady operation, the temperature of the heat recovery unit 3 becomes sufficiently high due to the hydrogen and methane gas contained in the anode exhaust gas supplied from the PEFC 1 via the anode exhaust gas supply pipe 26, and these heats cause the heat recovery unit 3 to have a high temperature. The reforming reaction proceeds inside the heat exchanger (reforming catalyst) 12 installed in, and becomes a reformed gas containing about 40% (dry) hydrogen. At this time, in the heat exchanger (reforming catalyst) 12 inside the heat recovery unit 3, a large amount of heat is consumed by the granular reforming catalyst 23 close to the combustion catalyst 11, and further, that is, the downstream, that is, the granular reforming catalyst 23 is filled. Heat is consumed in evaporation of water supplied to the heat exchanger and preheating of city gas in the heat exchanger part that is not. For this reason, the temperature of the exhaust gas discharged | emitted from the heat recovery device 3 falls to 120 degreeC, and the heat generated by the anode exhaust gas is effectively used.

  Next, the reaction gas generated in the heat exchanger (reforming catalyst) 12 inside the heat recovery unit 3 is supplied to the hydrogen production apparatus main body 2a through the raw material supply pipe 42, and the raw material (city gas and Steam) is converted to hydrogen. At this time, air is supplied by the air blower 14 to the raw material mixing unit 4 of the hydrogen production apparatus main body 2a in order to supplement heat necessary for the reforming reaction. Here, the amount of air to be supplied is controlled by the controller 22 so that the outlet temperature of the reforming catalyst 6 becomes the predetermined temperature (580 to 620 ° C.) as described above. Since the reforming reaction partially proceeds in the internal heat exchanger (reforming catalyst) 12 and the amount of methane in the reaction gas is reduced, the amount of air can be reduced accordingly.

  An example of the specific gas amount and the temperature of each part at this time is shown in FIG. For comparison, an example of the temperature of each part in the prior art is shown in the figure. In the prior art, the amount of heat of 10.2 kcal / min is contained in the anode exhaust gas of PEFC1, and this gas is combusted in the heat recovery unit, and the raw material gas flowing through the heat exchanger incorporated in the heat recovery unit Heat recovery. The temperature of the recovered heat source gas (city gas, air, water vapor) is about 500 ° C, while the exhaust gas temperature of the heat recovery unit is about 300 ° C, and the amount of heat released by the exhaust gas is about 4.0 kcal / min. Met. Further, the hydrogen concentration in the reformed gas obtained by charging the raw material preheated to 500 ° C. into the main body of the hydrogen production apparatus and introducing air of about 14.5 LN / min was about 47%.

  On the other hand, according to the present embodiment, the heat exchanger (reforming catalyst) installed in the heat recovery unit 3 when the amount of heat of 10.2 kcal / min is contained in the anode exhaust gas of PEFC1. The reformed gas discharged from the heat exchanger (reforming catalyst) 12 of the heat recovery unit 3 because a part of the reforming reaction (endothermic reaction) proceeds at the portion filled with the 12 granular reforming catalysts 23. Becomes a gas of about 500 ° C. with a hydrogen concentration of 40% (dry) and methane of 45% (dry). Since the heat in the anode exhaust gas is used by the reforming reaction (endothermic reaction) that partially proceeds, the exhaust gas temperature of the heat recovery device 3 becomes 120 ° C., and the amount of heat released by the exhaust gas is 1.7 kcal / Reduced to minutes. Moreover, the hydrogen concentration in the reformed gas obtained by introducing the reformed gas preheated to 500 ° C. into the small hydrogen production device and introducing air of about 10 LN / min is 54%, which is an improvement of 7%. Was confirmed. Moreover, it turned out that a power generation efficiency can be improved by 2.5 points by this Embodiment.

  In the case of the present embodiment, even when the heat amount (hydrogen amount) of the anode exhaust gas changes due to fluctuations in the operation status of the PEFC 1, the reaction amount at the granular reforming catalyst 23 installed inside the heat recovery device 3 is automatically set. There is an advantage that the amount of heat dissipation can be suppressed.

  For example, when the amount of hydrogen consumed in PEFC1 decreases, that is, when the amount of power generation in PEFC1 decreases, the amount of hydrogen in the anode exhaust gas increases. At this time, in the combustion catalyst 5 of the heat recovery unit 3, the combustion temperature increases as the amount of hydrogen increases. In the conventional structure, since the amount of heat exchanged by the heat exchanger is substantially the same, the increased amount of heat was released from the exhaust gas.

  On the other hand, in the present embodiment, when the combustion temperature of the combustion catalyst 5 of the heat recovery device 3 becomes high, the granular reforming catalyst 23 filled in the heated fluid flow path inside the heat exchanger (reforming catalyst) 12. Temperature rises. As the temperature of the reforming reaction increases, the amount of reaction increases, so the amount of reforming reaction (endothermic reaction) in the reforming catalyst portion increases, and heat is absorbed accordingly. Therefore, the exhaust gas temperature hardly changes and the heat dissipation amount does not increase.

According to the present embodiment, it is possible to reduce the amount of heat dissipated in the heat recovery device without increasing the heat exchanger of the heat recovery device and without causing thermal decomposition of the raw material. It has become possible to improve the efficiency of manufacturing equipment.
(Second Embodiment)
Next, a second embodiment according to the present invention will be described with reference to the drawings. The present embodiment is different from the first embodiment only in the structure of the heat recovery unit, and the system configuration is the same as that of the first embodiment. Therefore, only the structure of the heat recovery unit is shown in FIG.

  The heat recovery device 3a of the present embodiment is different from the heat recovery device 3 of the first embodiment in that an evaporator 31 is newly provided between the combustion catalyst 11 and the heat exchanger (reforming catalyst) 12. The installed point and the water supply pipe 25 are connected to the inlet side of the heated fluid passage of the heat exchanger 31a built in the evaporator 31, and the outlet side of the heated fluid passage is the city gas supply pipe 24. It is a point connected to. In this case, the structure becomes complicated, but since the supplied water can be reliably evaporated and then supplied to the granular reforming catalyst 23 packed in the heat exchanger (reforming catalyst) 12, the granular reforming by evaporation of water is possible. There is an effect of preventing deterioration of the catalyst 23 and the like.

According to the present embodiment, in addition to the effect in the first embodiment, an effect of preventing the deterioration of the granular reforming catalyst 23 and the like can be obtained.
(Third embodiment)
FIG. 5 shows a main configuration of the third embodiment based on the present invention. The present embodiment is different from the first embodiment in that an air supply pipe 33 is connected to the city gas supply pipe 24 and air is supplied to the city gas supply pipe 24 through the air supply pipe 33. Is the point where is placed. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted.

  The reason why the air is sent to the city gas supply pipe 24 is that, for fuel types such as LNG and kerosene, the reforming reaction can proceed stably by introducing a small amount of air into the reforming catalyst section. The basic concept and effect are the same as those of the first embodiment.

1 is a system diagram showing a main configuration of a fuel cell power generation system according to a first embodiment of the present invention. It is sectional drawing which shows the structure of the heat recovery device of 1st Embodiment shown in FIG. It is a figure which compares and shows the state characteristic of each part of the fuel cell power generation system of the 1st Embodiment of this invention, and the conventional fuel cell power generation system. It is a block diagram which shows the structure of the heat recovery device of the fuel cell power generation system which concerns on the 2nd Embodiment of this invention. It is a systematic diagram which shows the principal part structure of the fuel cell power generation system which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

1 PEFC
DESCRIPTION OF SYMBOLS 2 Hydrogen production apparatus 3 Heat recovery device 4 Raw material mixing part 5 Combustion catalyst 6 Reforming catalyst 7 CO converter 8 CO remover 9 Startup burner 10 Startup burner 11 Combustion catalyst 12 Heat exchanger (reforming catalyst)
DESCRIPTION OF SYMBOLS 13 Heat exchanger 14,15 Air blower 16,17 City gas blower 18,19 Water pump 20 Air blower 21 Temperature measuring device 22 Controller 23 Granular reforming catalyst 24 City gas supply pipe 25 Water supply pipe 26 Anode exhaust gas supply pipe 27 Air Supply pipe 28 Water heat exchanger 29 City gas heat exchanger 30 Air heat exchanger 31 Evaporator 32 Air blower 33 Air supply pipe 34 Reformed gas supply pipe 36 Air supply pipe 38 Water supply pipe 39 Water vapor supply pipe 42 Raw material supply pipe 43 Air supply pipe 44, 45 Valve 46 Reformed gas bypass pipe

Claims (7)

  Hydrocarbon fuel, reformed gas generating means for generating reformed gas containing hydrogen by a reforming reaction by a reforming catalyst using oxygen or air and water or steam as raw materials, and the generated reformed gas as fuel A fuel cell power generation system comprising: a fuel cell for generating electricity; and a heat recovery device for recovering heat by burning anode exhaust gas of the fuel cell, wherein the heat recovery device is covered with a reforming catalyst. A heat exchanger including a heated fluid flow path, a means for supplying hydrocarbon fuel and water or water vapor to the heated fluid flow path, and a fluid passing through the heated fluid flow path A fuel cell power generation system comprising: a conduit leading to the quality gas generating means.   2. The fuel cell power generation system according to claim 1, further comprising: a temperature measuring unit that measures the temperature of the reformed gas at a reformed gas outlet of the reforming catalyst of the reformed gas generating unit; and further, a measured value by the temperature measuring unit. A fuel cell power generation system provided with a controller for adjusting the amount of air supplied to the reformed gas generation means so that is in a predetermined temperature range.   3. The fuel cell power generation system according to claim 1, further comprising means for supplying air in addition to the hydrocarbon fuel and water or water vapor to the heated fluid flow path.   The fuel cell power generation system according to any one of claims 1 to 3, wherein an evaporator for evaporating water is installed upstream of the heating fluid channel of the heat exchanger, and the generated water vapor flows into the heated fluid channel. It is comprised so that it may be supplied to, The fuel cell power generation system characterized by the above-mentioned.   5. The fuel cell power generation system according to claim 1, further comprising means for supplying hydrocarbon fuel to a combustion part to which anode exhaust gas of the heat recovery unit is supplied. Power generation system.   6. A fuel cell power generation system operating method for operating the fuel cell power generation system according to claim 1, wherein an amount of air supplied to the reformed gas generating means is increased at startup than during steady operation. A method for operating a fuel cell power generation system. 6. A fuel cell power generation system operating method for operating the fuel cell power generation system according to claim 5, wherein at the time of start-up, a hydrocarbon-based fuel is supplied to a combustion section to which anode exhaust gas of the heat recovery unit is supplied, and anode exhaust gas A method for operating a fuel cell power generation system, comprising a step of stopping the supply of the hydrocarbon-based fuel at the time when the occurrence of the fuel is generated.

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