JP2006302881A - Fuel cell assembly - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell assembly capable of preparing the most preferable catalyst environment. <P>SOLUTION: The solid fuel battery assembly has a housing defining power generation/burning chambers, a cell stack disposed in the housing, a catalyst containing case 78a, a tube 82a for supplying a gas to be reformed that is disposed in the catalyst containing case 78a, and a fuel gas supply tube 80a. A reforming catalyst is contained in the catalyst containing case 78a. A temperature detection device 105 is provided in the catalyst containing case 78a and the temperature detection device 105 is connected to a measuring device at the outside of the housing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel cell assembly in which raw material gas is reformed and / or desulfurized by the action of a catalyst and supplied to a cell stack, and more particularly, surplus fuel gas burns in a housing to heat a catalyst storage case. The present invention relates to a fuel cell assembly.

  In recent years, various types of fuel cell power generation systems such as solid polymer, phosphoric acid, molten carbonate, and solid oxide have been proposed as next-generation energy.

  2. Description of the Related Art Conventionally, a polymer electrolyte fuel cell includes a housing in which a power generation element is accommodated and a reformer disposed outside the housing, and surplus fuel gas in the fuel gas supplied to the power generation element. Was introduced into the reformer and combusted to heat the reformer in the reformer. Further, since the reformer cannot be heated sufficiently only by surplus fuel gas combustion, the fuel gas is separately introduced into the reformer from the outside and burned, and the temperature of the reformer becomes constant. Had been heated.

  On the other hand, the solid oxide fuel cell power generation system has advantages such as high operating temperature, high power generation efficiency, and use of waste heat, and research and development are being promoted.

A typical example of a fuel cell power generation system includes a fuel cell assembly including a housing that defines a power generation / combustion chamber and a cell stack disposed in the housing, as disclosed in Patent Document 1 below. (For example, refer to Patent Document 1). Recently, it has been proposed to arrange a storage case in which a gas introduction unit and a gas extraction unit are attached to the fuel cell assembly. An appropriate reforming catalyst is accommodated in the storage case, the raw material gas is introduced into the storage case through the gas introduction means, receives the action of the catalyst, and the fuel gas is supplied to the cell stack through the gas outlet means. The cell stack is also supplied with oxygen-containing gas, which may be air, and a required power generation reaction is generated in each cell to generate power.
JP 2000-149976 A

  However, in a solid oxide fuel cell, when a reformer (catalyst storage case) is disposed in the housing, the reformer is heated by the heat generated by the fuel cell or exhaust gas, and the raw material is produced by the catalyst in the reformer. Gas is reformed and supplied to the cell stack as fuel gas. However, it is difficult to control the heating status of the reformer because the reformer is heated by the amount of heat and exhaust gas generated by power generation. As a result, the reforming performance of the raw material gas changes, which has a problem of greatly affecting the power generation performance.

  In particular, when the amount of power generated by the fuel cell is changed according to the power demand (load fluctuation), the amount of heat generated by the power generation also changes, and the amount of exhaust gas also changes. It was difficult to obtain a good reformer environment.

  In recent years, fuel gas is burned in the housing. In this case, the amount of heat generated by the combustion gas fluctuates due to load fluctuations, making it difficult to obtain an optimal catalyst environment.

  An object of the fuel cell assembly of the present invention is to provide a fuel cell assembly capable of obtaining an optimum catalyst environment.

  The fuel cell assembly of the present invention includes a housing defining a power generation chamber, a cell stack disposed in the housing, a catalyst storage case disposed in the housing, and the catalyst storage case. A fuel cell assembly comprising a gas introduction means and a gas lead-out means attached to the catalyst storage case, wherein the catalyst storage case contains a reforming catalyst and / or a desulfurization catalyst, and the gas introduction The raw material gas introduced into the catalyst storage case through the means receives the action of the catalyst and is supplied to the cell stack through the gas outlet means, and the catalyst storage case is provided with temperature detection means and / or pressure detection means. The temperature detecting means and / or the pressure detecting means are connected to a measuring device outside the housing.

  In such a fuel cell assembly, since the temperature detection means and / or the pressure detection means are provided in the catalyst storage case, even when the power generation amount of the fuel cell is changed according to the power demand, the catalyst is also generated by the combustion gas. Even when the storage case is heated, the temperature distribution and pressure distribution in the catalyst storage case can be grasped, and an optimum catalyst environment can be obtained. For example, when an abnormal temperature distribution occurs in the catalyst storage case, the optimum catalyst environment can be controlled by changing the power generation amount, the fuel utilization rate, the air utilization rate, etc., as will be described later. In addition, when an abnormal pressure distribution occurs in the catalyst storage case, it can be controlled to the optimum catalyst environment by changing the fuel supply amount, the water vapor amount, etc., depending on the situation of the fuel cell at that time Provide an optimal catalyst environment. In addition, the catalyst storage case can be monitored and controlled so that no abnormality occurs, and an emergency stop can be performed when improvement by operating condition control is difficult when an abnormality occurs.

  Further, the fuel cell assembly of the present invention is characterized in that the temperature detecting means is provided at a raw material gas inlet and / or a raw material gas outlet in the catalyst of the catalyst storage case.

  When the catalyst acts on the raw material gas, heat generation and endotherm are generated by the catalytic reaction between the raw material gas inlet portion and the raw material gas outlet portion of the catalyst, and various temperature distributions can occur. At this time, the temperatures of the raw material gas inlet and the raw material gas outlet are important for the catalyst performance and the life. By detecting the temperature of at least one of these and feeding it back to operation control, an optimal catalyst environment can be obtained.

  In the fuel cell assembly of the present invention, when the temperature detection means of the catalyst storage case detects that the temperature of the raw material gas inlet deviates from the set temperature range, the temperature of the raw material gas inlet is Can be controlled so as to be within the set temperature range, or the operation can be stopped.

  As described above, the influence of the temperature of the raw material gas inlet of the catalyst on the catalyst performance and life is great. For example, in a reforming catalyst, a temperature fluctuation exceeding an allowable range may occur in the catalyst storage case depending on the operating state of the solid oxide fuel cell. This temperature fluctuation causes an excessive amount of the raw material gas inlet of the catalyst. Increased temperature may cause carbon deposition. However, when the temperature of the raw material gas inlet of the catalyst detected by the temperature detecting means is higher than the predetermined upper limit value, it can be kept within the set temperature range by feeding back to the operation control and changing the operation condition.

  Alternatively, the catalyst can be prevented from being deteriorated by stopping the operation, and the operation can be stopped safely.

  In the fuel cell assembly of the present invention, the catalyst storage case has a water vaporization section, and when the temperature of the raw material gas inlet in the catalyst of the catalyst storage case is higher than a set temperature range, the catalyst storage case is provided. It is characterized by comprising a control device that controls to increase the amount of water supplied to the water vaporization section of the case.

  As a specific operation control method for the catalyst overheating at the inlet of the catalyst, the raw material gas and water vapor act on the catalyst (reforming) to generate the fuel necessary for power generation. By increasing the amount of water, the temperature of the raw material gas inlet portion of the adjacent catalyst is lowered by the endotherm accompanying the water vaporization in the water vaporization portion, and the mixed gas temperature of the raw material gas and water vapor supplied to the catalyst is lowered. Thus, carbon deposition can be prevented.

  In the fuel cell assembly of the present invention, when it is detected by the temperature detection means of the catalyst storage case that the temperature of the catalyst source gas outlet deviates from the set temperature range, the catalyst source gas The operating condition can be controlled or the operation can be stopped so that the temperature of the outlet is within the set temperature range.

  As described above, the temperature of the raw material gas outlet of the catalyst has a great influence on the catalyst performance and life. For example, in a reforming catalyst, a temperature fluctuation exceeding an allowable range may occur in the catalyst storage case depending on the operation state, and if the temperature of the raw material gas outlet of the catalyst rises excessively due to this temperature fluctuation, the sintering is performed. May cause catalyst deterioration. Conversely, when the temperature of the catalyst raw material outlet is lower than the predetermined temperature, the predetermined reforming reaction is not performed and a large amount of hydrocarbons is supplied to the fuel cell, and carbon deposition may occur in the fuel cell. There is sex. However, when it is detected that the temperature of the raw material gas outlet of the catalyst deviates from the set temperature range, it can be kept within the set temperature range by feeding back to the operation control and changing the operation conditions. Alternatively, the catalyst can be prevented from being deteriorated by stopping the operation, and the operation can be stopped safely.

  The fuel cell assembly according to the present invention increases the amount of oxygen source supplied to the catalyst in the catalyst storage case when the temperature of the source gas outlet of the catalyst in the catalyst storage case is lower than the set temperature range. A control device for controlling is provided.

  As a specific operation control method for the temperature drop of the raw material gas outlet part, the oxygen source to the catalyst, for example, the amount of water vapor or air is increased, or as described above, when the catalyst storage case has a water vaporization part, By increasing the amount of water to the water vaporization section, the conversion rate of the reforming reaction can be increased, the amount of hydrocarbons supplied to the fuel cell can be reduced, and carbon deposition can be prevented.

  Water vapor and air can be used as the oxygen source. As a specific operation control method for the temperature drop of the raw material gas outlet, the reforming reaction is usually performed by a steam reforming method in which steam and hydrocarbon endothermically react. If a reforming reaction cannot be obtained, a predetermined amount of air is mixed in the hydrocarbon and supplied to the reforming catalyst, and a partial oxidation reaction that exothermicly reacts air and hydrocarbons occurs simultaneously, resulting in a lack of heat in the catalyst. In addition, carbon deposition can be prevented by increasing the oxygen source.

  The fuel cell assembly of the present invention is characterized in that surplus fuel gas that has not been used in the cell stack burns, and the catalyst storage case is heated by the combustion gas. In such a fuel cell assembly, the catalyst storage case can be efficiently heated. However, since the temperature distribution and pressure distribution are likely to occur in the catalyst storage case, the present invention can be used effectively.

  In the fuel cell assembly of the present invention, when the surplus fuel gas burns and the catalyst storage case is heated by the combustion gas, the temperature of the raw material gas outlet in the catalyst of the catalyst storage case is lower than the set temperature range. When it is low, a control device is provided for controlling the fuel utilization rate to decrease.

  As a specific operation control method for the temperature drop at the source gas outlet of the catalyst, more fuel is required to produce the same output by controlling the utilization rate of the fuel used for power generation to be reduced. However, since the surplus fuel amount increases, the amount of combustion heat substantially increases, and the temperature of the raw material gas outlet of the catalyst can be raised.

  Further, the fuel cell assembly of the present invention reduces the air utilization rate when the temperature of the raw material gas inlet and the raw material gas outlet in the catalyst of the catalyst storage case is higher than the set temperature range. If it is too low, a control device is provided for controlling the air utilization rate to be increased.

  As a specific operation control method for the temperature of the raw material gas inlet and the raw material gas outlet, if the temperature of each part detected by the temperature detection means of the catalyst storage case is higher than a predetermined upper limit value, use of air used for power generation By controlling so as to reduce the rate, and by increasing the supply amount of power generation air and cooling the entire fuel cell assembly, the temperature of each part can be lowered and the catalyst overheating can be prevented. In addition, when the temperature of each part detected by the temperature detection means of the catalyst storage case is lower than the predetermined lower limit value, control is performed to improve the utilization rate of air used for power generation, and the supply amount of power generation air is reduced. By raising the temperature of the entire fuel cell assembly, it is possible to raise the temperature of each part and prevent reforming defects and the like.

  The fuel cell assembly of the present invention includes a housing defining a power generation chamber, a cell stack disposed in the housing, a catalyst storage case disposed in the housing, and the catalyst storage case. A fuel cell assembly comprising a gas introduction means and a gas lead-out means attached to the catalyst storage case, wherein the catalyst storage case contains a reforming catalyst and / or a desulfurization catalyst, and the gas introduction The raw material gas introduced into the catalyst storage case through the means is subjected to the action of the catalyst and supplied to the cell stack through the gas outlet means, and the gas introduction means is provided with a pressure detection means, and the pressure detection means When the pressure detected by the pressure detection means is higher than the set pressure range, the catalyst storage case is touched. Characterized by comprising a control device for controlling so as to increase the oxygen source supply to.

  By detecting the pressure loss in the above portion by the pressure detecting means, the carbon deposition state in the reformer and the fuel cell can be monitored. For example, when carbon deposition occurs inside the catalyst storage case, the flow path is narrowed by the carbon, so that the pressure loss inevitably increases, and the differential pressure from the atmospheric pressure exhausted from the system increases. As a result, if the detected pressure loss increases, it can be determined that an unfavorable state has occurred in operation.

  In this case, the present invention provides a control device that controls to increase the amount of oxygen source supplied to the catalyst in the catalyst storage case when the pressure detected by the pressure detecting means is higher than a set pressure range. It is characterized by comprising. That is, when the pressure value detected by the pressure detection means of the catalyst storage case is higher than the predetermined upper limit value, the amount of water vapor or air as an oxygen source is temporarily increased and then returned to the original condition. Is controlled to be less than or equal to a predetermined upper limit value. For example, when carbon deposition occurs on the reforming catalyst and an increase in pressure loss in the reforming section is detected by the pressure detection means as a precursor to gas channel blockage, the supply amount of oxygen sources such as water and air temporarily Is increased to promote the gasification reaction of the precipitated carbon and the oxygen source and remove the precipitated carbon. Thereby, a catalyst life can be extended and reliability can be ensured over a long period of time.

  Moreover, when the value detected by the pressure detection means of the catalyst storage case is out of the predetermined range, the operation of the fuel cell system can be stopped urgently. When a value exceeding a preset range is detected by the detection means, it is determined that a system abnormality has occurred, and an emergency stop is performed before an accident or the like, so that a fuel cell system with excellent safety can be obtained. it can.

  Further, the fuel cell assembly of the present invention is characterized in that surplus fuel gas that has not been used in the cell stack burns, and the catalyst storage case is heated by the combustion gas. The catalyst storage case is exposed to a combustion flame of excess fuel gas.

  In such a fuel cell assembly, the catalyst storage case can be efficiently heated. However, since the temperature distribution and pressure distribution are likely to occur in the catalyst storage case, the present invention can be used effectively.

  Further, the catalyst storage case is substantially elongated and is located above the cell stack. In such a fuel cell assembly, not only has the structure capable of effectively exposing the catalyst storage case to the combustion gas, but also the fuel gas and the reforming catalyst can be efficiently contacted.

  Further, the fuel cell assembly of the present invention is characterized in that the load fluctuates. It is desirable to be used for distributed generation of 5 kW or less for home use. In such a fuel cell assembly, the heating amount of the catalyst storage case due to the generated heat and combustion gas also fluctuates due to load fluctuations, and the size of the housing becomes small and the temperature in the housing is likely to change. It can be used suitably.

  Furthermore, the fuel cell assembly of the present invention is characterized in that the power generation temperature is 800 ° C. or lower. In such a fuel cell assembly, since the power generation temperature is low, the heating amount of the catalyst housing case is low in the first place, and therefore the present invention can be suitably used.

  In the fuel cell assembly of the present invention, it is desirable that the catalyst storage case is sequentially provided with a water vaporization section, a reforming catalyst section, and a reformed gas preheating section from the portion where the gas introduction means is connected. . In such a fuel cell assembly, it is possible to reduce the size by an integrated structure with the water vaporization unit, and the reformed gas temperature is raised by the reformed gas preheating unit installed downstream of the reforming catalyst unit, so that the cell The reformed gas supply temperature can be increased, and the self-sustained operation can be performed even in a state where the temperature of the power generation unit is likely to decrease, such as during low-load operation.

  Furthermore, in the fuel cell assembly of the present invention, the water vaporization unit is installed in the vicinity of the reforming catalyst unit inlet, and the raw material gas and the water vapor can be mixed in the previous stage of the reforming catalyst unit. In such a fuel cell assembly, it is possible to prevent carbon deposition due to excessive temperature rise of the fuel gas by installing a water vaporization unit in the vicinity of the reforming catalyst inlet.

  Further, in the fuel cell assembly of the present invention, the temperature detection means can be provided on the outer surface of the catalyst storage case and can be connected to a measuring device outside the housing. In such a fuel cell assembly, the exact temperature inside the catalyst storage case cannot be detected. However, by estimating the temperature difference between the inside and the outer wall of the catalyst storage case in advance, the temperature of the catalyst storage case can be very easily determined. I can grasp it.

  The fuel cell assembly of the present invention can grasp the temperature distribution and pressure distribution in the catalyst storage case, so that, for example, even when the power generation amount of the fuel cell is changed according to the power demand, Even when the catalyst storage case is heated by the combustion gas, an optimal catalyst environment can be obtained.

  The fuel cell assembly of the present invention will be described with reference to FIGS. 1, 2, and 3. The fuel cell assembly includes a substantially rectangular parallelepiped housing 2. The outer surface of the six wall surfaces of the housing 2 is a heat insulating wall (heat insulating member) formed of an appropriate heat insulating material, that is, the upper heat insulating wall 4, the lower heat insulating wall 6, the right heat insulating wall 8, the left heat insulating wall 9, and the front A heat insulating wall 10 and a rear heat insulating wall 11 are provided. A power generation / combustion chamber 12 is defined in the housing 2.

  The front heat insulation wall 10 and / or the rear heat insulation wall 11 is detachably or removably attached, and the front heat insulation wall 10 and / or the rear heat insulation wall 11 is detached or opened to access the power generation / combustion chamber 12. be able to. If desired, an outer wall, which may be made of a metal plate, can be disposed on the outer surface of each heat insulating wall.

  An air chamber (gas chamber) 16 is disposed at the upper end of the housing 2. The air chamber 16 is defined in a rectangular parallelepiped case 17 having a relatively small vertical dimension. The air chamber 16 communicates with the upper end of an air introduction pipe (gas supply means) 22 for sending air (oxygen-containing gas) toward the power generation / combustion chamber. There are a plurality of air introduction pipes 22 and the shape thereof may be a cylinder or a hollow plate structure. 1 and 2, a cylindrical air introduction tube 22 is shown. The air introduction pipe 22 is disposed between the cell stacks described later, and has an opening at the lower end portion of the cell, and air is ejected from the opening portion. The air introduction tube 22 is preferably made of a material having high heat resistance such as ceramics.

  A low temperature gas supply pipe 18 is provided in the air chamber 16, and the low temperature gas supply pipe 18 penetrates the upper heat insulating wall 4 and extends to the outside.

  The low-temperature gas supply pipe 18 supplies the same type of gas as that supplied into the air chamber 16, that is, low-temperature air, into the air chamber 16. The air supplied through the low-temperature gas supply pipe 18 is It must be cooler than the temperature of the preheated air. In particular, about room temperature is desirable.

  As shown in FIG. 2, the low temperature gas supply pipe 18 is connected to a position of the air chamber 16 that cools the power generation units 56a, 56b, 56c, and 56d, that is, the central portion of the fuel cell assembly. In other words, the air introduction pipe 22 disposed between the power generation units 56a, 56b, 56c, and 56d has a low temperature so as to open at the position of the opposing case 17 side plate with respect to the center of the opening assembly to the case 17 side plate. A gas supply pipe 18 is provided.

  A heat exchanger 24 having a flat plate shape as a whole is disposed on both sides of the housing 2, more specifically, inside the right heat insulating wall 8 and inside the left heat insulating wall 9. Each of the heat exchangers 24 is constituted by a case 26 having a hollow flat plate shape extending substantially vertically.

  A partition plate 28 located in the middle in the lateral direction is disposed in the case 26, and the inside of the case 26 is partitioned into a discharge path 30 positioned on the inner side and an inflow path 32 positioned on the outer side. Three partition walls 34 and 36 are arranged in the discharge path 30 at intervals in the vertical direction. More specifically, in the discharge passage 30, the front edge is located rearwardly away from the front wall (not shown) of the case 26, but the rear edge is the rear wall (not shown) of the case 26. And a partition wall 36 whose front edge is connected to the front wall of the case 26 but whose rear edge is spaced forward from the rear wall of the case 26. Are alternately arranged, and thus the combustion gas discharge passage 30 is zigzag-shaped. If desired, a form other than the zigzag flow path may be used.

  Similarly, the three partition walls 38 and 40, that is, the front edges thereof are also spaced apart from the front wall (not shown) of the case 26 in the inflow path 32 with a space in the vertical direction. The rear wall is connected to the rear wall (not shown) of the case 26, and the front edge of the partition wall 38 is connected to the front wall of the case 26. The partition walls 40 spaced apart from the front are alternately arranged, and thus the inflow passage 32 is also zigzag-shaped. If desired, a form other than the zigzag flow path may be used.

  A discharge opening 42 is formed at the upper end of the inner wall of the case 26, and the discharge path 30 is communicated with the power generation / combustion chamber 12 through the discharge opening 42. In the illustrated embodiment, heat storage walls (heat shielding members) made of a heat storage material are arranged on the power generation / combustion chamber 12 side of the heat exchanger 24, that is, on the fuel cell side and above and below the fuel cell. Has been. That is, the right heat storage wall 44a, the left heat storage wall 44b, the front heat storage wall 44c, the rear heat storage wall 44d, the lower heat storage wall 44e, and the upper heat storage wall 44f are disposed so as to surround the cell assembly. An opening 45 is formed in the upper part of the right heat storage wall 44 a and the left heat storage wall 44 b so as to be located at substantially the same height as the lower edge of the discharge opening 42, and the discharge opening 42 generates power through the opening 45. -It is connected to the combustion chamber 12.

The heat insulating walls 4, 6, 8, 9, 10, and 11 formed on the outer surface of the six wall surfaces of the housing 2 are formed of an alumina / silica general-purpose heat insulating material so as to surround the cell assembly. The heat storage walls 44 a, 44 b, 44 c, 44 d, 44 e, 44 f are formed from a heat insulating material having a higher alumina purity than the heat insulating materials 4, 6, 8, 9, 10, 11. The heat insulating walls 4, 6, 8, 9, 10, 11 and the heat storage walls 44a, 44b, 44c, 44d, 44e, 44f may be formed of the same material, but the density of the heat storage material is larger than that of the heat insulating material. Is desirable. The heat insulating walls 4, 6, 8, 9, 10, 11 have a density of 0.26 g / cm ³ or less, and the heat storage walls 44a, 44b, 44c, 44d, 44e, 44f have a density of 0.32 g / cm ³ or less. The thermal conductivity of is preferably 0.1 to 0.4 W / (m · K).

  An inflow opening 48 is formed on the outer side of the upper wall of the case 26, and the inflow path 32 is communicated with the air chamber 16 through the inflow opening 48. The heat exchanger 24 and the inflow opening 48 constitute a gas supply channel. A double cylinder 50 (only the upper end portion is shown in FIG. 1) extending in the vertical direction is disposed behind each of the inflow passages 32. The double cylinder 50 is an outer cylinder member. 52 and an inner cylindrical member 54. The lower end of the discharge path 30 is connected to the lower end of the discharge path defined between the outer cylinder member 52 and the inner cylinder member 54, and the lower end of the inflow path 32 is defined in the inner cylinder member 54. Connected to the inflow channel.

  Four power generation units 56a, 56b, 56c and 56d are arranged in the lower part of the above-described power generation / combustion chamber. The power generation units 56a, 56b, 56c, and 56d are respectively positioned between the air introduction pipes 22 described above. In other words, the air introduction pipe 22 is disposed between the power generation units 56a, 56b, 56c and 56d. 3 and 4 together with FIGS. 1 and 2, the power generation unit 56a includes a rectangular parallelepiped fuel gas case 58a extending in the front-rear direction (direction perpendicular to the paper surface in FIG. 1). .

  A cell stack 60a is mounted on the upper surface of the fuel gas case 58a that defines the fuel gas chamber. The cell stack 60a is configured by arranging a plurality of upright cells 62 extending in the vertical direction in the longitudinal direction of the fuel gas case 58a (that is, in the front-rear direction). As clearly shown in FIG. 5, each cell 62 includes an electrode support substrate 64, a fuel electrode layer 66 that is an inner electrode layer, a solid electrolyte layer 68, an oxygen electrode layer 70 that is an outer electrode layer, and an interconnector 72. Has been.

  The electrode support substrate 64 is a columnar plate-like piece that is elongated in the vertical direction, and the cross-sectional shape thereof has both flat surfaces and both sides of a semicircular shape. The electrode support substrate 64 is formed with a plurality (six in the illustrated example) of fuel gas passages 74 penetrating the electrode support substrate 64 in the vertical direction. Each of the electrode support substrates 64 is bonded to the upper wall of the fuel gas case 58a by, for example, a ceramic adhesive having excellent heat resistance.

  On the upper wall of the fuel gas case 58a, a plurality of slits (not shown) extending in the left-right direction are formed at intervals in a direction perpendicular to the paper surface in FIG. A fuel gas passage 74 is communicated with the fuel gas chamber according to each of the slits.

  The interconnector 72 is disposed on one side of the electrode support substrate 64 (upper surface in the cell stack 60a in FIG. 5). The fuel electrode layer 66 is disposed on the other surface (the lower surface in the cell stack 60a of FIG. 5) and both side surfaces of the electrode support substrate 64, and both ends thereof are joined to both ends of the interconnector 72. The solid electrolyte layer 68 is disposed so as to cover the entire fuel electrode layer 66, and both ends thereof are joined to both ends of the interconnector 72. The oxygen electrode layer 70 is disposed on the main part of the solid electrolyte layer 68, that is, on the portion covering the other surface of the electrode support substrate 64, and is positioned to face the interconnector 72 with the electrode support substrate plate 64 interposed therebetween. Yes.

  A current collecting member 76 is disposed between adjacent cells 62 in the cell stack 60a, and connects the interconnector 72 of one cell 62 and the oxygen electrode layer 70 of the other cell 62. Current collecting members 76 are disposed on both ends of the cell stack 60a, that is, on one side and the other side of the cell 62 positioned at the upper end and the lower end in FIG. Electric power extraction means (not shown) is connected to the current collecting members 76 located at both ends of the cell stack 60a, and the electric power extraction means is the front heat insulation wall 10, the rear heat insulation wall 11 or the lower heat insulation wall of the housing 2. The material 6 extends outside the housing 2. If desired, the cell stacks 60a, 60b, 60c and 60d are connected in series with each other by appropriate connection means instead of disposing the power extraction means in each of the cell stacks 60a, 60b, 60c and 60d. Common power extraction means may be provided for the cell stacks 60a, 60b, 60c and 60d.

  More specifically about the cell 62, the electrode support substrate 64 is gas permeable to allow fuel gas to permeate to the anode layer 66, and is also conductive to collect current through the interconnector 72. Can be formed from a porous conductive ceramic (or cermet) that satisfies such requirements.

  In order to manufacture the cell 62 by co-firing with the fuel electrode layer 66 and / or the solid electrolyte layer 68, it is preferable to form the electrode support substrate 64 from the iron group metal component and the specific rare earth oxide. In order to provide the required gas permeability, it is preferred that the open porosity is in the range of 30% or more, in particular 35 to 50%, and the conductivity is also 300 S / cm or more, in particular 440 S / cm or more. Is preferred.

The fuel electrode layer 66 can be formed of a porous conductive ceramic, for example, ZrO ₂ (referred to as stabilized zirconia) in which a rare earth element is dissolved and Ni and / or NiO.

The solid electrolyte layer 68 has a function as an electrolyte for bridging electrons between electrodes, and at the same time needs to have a gas barrier property in order to prevent leakage between fuel gas and air. In general, it is formed from ZrO ₂ in which ₃ to 15 mol% of a rare earth element is dissolved.

The oxygen electrode layer 70 can be formed of a conductive ceramic made of a so-called ABO ₃ type perovskite oxide. The oxygen electrode layer 70 needs to have gas permeability, and the open porosity is preferably 20% or more, particularly preferably in the range of 30 to 50%.

Although the interconnector 72 can be formed from a conductive ceramic, it needs to have a reduction resistance and an oxidation resistance in order to come into contact with a fuel gas and air that may be hydrogen gas. A perovskite oxide (LaCrO ₃ oxide) is preferably used. The interconnector 72 must be dense in order to prevent leakage of fuel gas passing through the fuel gas passage 74 formed in the electrode support substrate 64 and air flowing outside the electrode support substrate 64, and is 93% or more. In particular, it is desired to have a relative density of 95% or more.

  The current collecting member 76 can be composed of a member having an appropriate shape formed of a metal or alloy having elasticity, or a member obtained by adding a required surface treatment to a felt made of metal fiber or alloy fiber.

  Continuing the description with reference to FIG. 4, the power generation unit 56 a also includes a catalyst storage case 78 a that is preferably a rectangular shape (or a cylindrical shape) that is elongated in the front-rear direction above the cell stack 60 a. ing. One end, that is, the upper end of a fuel gas supply pipe 80a (gas outlet means) is connected to the front surface of the catalyst storage case 78a.

  The fuel gas supply pipe 80a extends downward, then curves and extends rearward, and the other end of the fuel gas supply pipe 80a is connected to the front surface of the fuel gas case 58a. One end of a reformed gas supply pipe 82a (gas introduction means) is connected to the rear surface of the catalyst storage case 78a. The reformed gas supply pipe 82a extends downward from the catalyst storage case, extends under the housing 2 and extends out of the housing 2.

  The to-be-reformed gas supply pipe 82a is connected to a to-be-reformed gas supply source (not shown) which may be a hydrocarbon gas such as city gas, and is connected to the catalyst storage case 78a through the to-be-reformed gas supply pipe 82a. A gas to be reformed (sometimes referred to as a source gas) is supplied. An appropriate reforming catalyst for reforming the raw material gas into a hydrogen-rich fuel gas is housed in the catalyst housing case 78a.

  In the illustrated embodiment, the catalyst storage case 78a is connected to the fuel gas case 58a via the fuel gas supply pipe 80a, and is thereby held at a required position. For example, an appropriate support member 84a can be provided between the lower surface of the reformed gas supply pipe 82a and the lower surface or rear surface of the rear end portion of the fuel gas case 58a.

  In the catalyst storage case 78a, as shown in FIG. 6, a reforming catalyst portion 102a filled with a catalyst suitable for reforming a raw material gas that may be desulfurized city gas into a hydrogen-rich fuel gas is provided. It has been. An example of a catalyst suitable for reforming city gas into hydrogen-rich fuel gas is a nickel-alumina catalyst. If desired, the catalyst storage case 78a can be filled with a desulfurization catalyst in addition to or in place of the reforming catalyst. It is necessary to arrange the reforming means separately downstream).

  A reformed gas supply pipe 82a and a water supply pipe (not shown) are connected to the catalyst storage case 78a, and fuel gas and water are supplied to the water vaporizer 109a. The water vaporized by the water vaporization unit 109a is vaporized and mixed with the raw material gas (sometimes referred to as the gas to be reformed) supplied at the same time, and supplied to the reforming catalyst 102a. The water vaporization part 109a prevents the carbon precipitation generated by the thermal decomposition of the raw material gas by preventing the excessive temperature rise of the raw material gas by the heat of vaporization of water, and obtains a desired temperature distribution in the reforming catalyst part 102a. be able to.

  Further, the same effect can be obtained by providing the water vaporization unit 109a as a separate structure so as to be adjacent to the vicinity of the inlet of the reforming catalyst unit 102a, and jetting and mixing water vapor in the previous stage of the reforming catalyst unit 102a. Although the water vaporization part 109a may have any structure, it is preferable to fill the inside with a heat-resistant member such as ceramics in order to increase the heat capacity. The catalyst is catalyzed by the reforming catalyst 102a and transformed into reformed gas, and then supplied to the reformed gas preheating unit 110a. The reformed gas preheating unit 110a can facilitate the thermal self-sustained operation by increasing the reformed gas temperature supplied to the power generation unit by further heating the reformed gas. Such a structure is more effective in a state where the amount of heat generated in the power generation unit such as low load operation is reduced. The reformed gas preheating unit 110a may have any structure, but it is preferable to fill a heat resistant member such as ceramics in order to increase the heat capacity. The reformed gas is supplied from the reformed gas preheating unit 110a to the fuel gas case (not shown) through the fuel gas supply pipe 80a.

  In addition, since the catalyst storage case 78a is installed in the housing 2, it is strongly influenced by the temperature distribution of the combustion / power generation chamber 12, so that the reforming conditions and the like may change, and the thermal balance of the entire fuel cell may be lost. There is. Therefore, it is important to accurately grasp the temperature and pressure conditions in the catalyst storage case 78a.

  In the present invention, the temperature detection means 105 is disposed in the catalyst storage case 78a, and the temperature detection means 105 is connected to a measuring device (not shown) outside the housing, so that the usage state of the catalyst can be accurately grasped. .

  That is, the temperature of the catalyst can be detected by the temperature detection means 105 in the catalyst storage case 78a, and the temperature distribution of the catalyst can be accurately grasped by accommodating a plurality of temperature detection means. The driving state can be realized. Examples of the temperature detecting means include a thermocouple, a radiation thermometer, etc., and these are connected to a measuring device outside the housing by a cable.

  A pressure detecting means can be provided in place of the temperature detecting means 105 in the catalyst storage case 78a. Thereby, the pressure in the catalyst storage case 78a can be detected, and an appropriate operation state can be realized. An example of the pressure detection means is a micro differential pressure gauge. For example, a pipe having an open end is provided in the catalyst storage case 78a, and this pipe is drawn out and connected to a measuring device outside the housing.

  In such a fuel cell assembly, since the temperature detection means 105 and / or the pressure detection means are provided in the catalyst storage case 78a, the temperature and pressure in the catalyst storage case 78a can be grasped. Even when the power generation amount of the fuel cell is changed in accordance with the power demand, or when the catalyst storage case is heated by the combustion gas, an optimal catalyst environment can be obtained.

  For example, if an abnormal temperature distribution occurs in the catalyst storage case, it can be controlled by changing the power generation amount, fuel utilization rate, air utilization rate, etc., or if an abnormal pressure distribution occurs, the fuel supply amount It can be controlled by changing the amount of water vapor and the like, and an optimal catalyst environment according to the state of the fuel cell at that time can be provided. In addition, the catalyst storage case can be monitored and controlled so that such an abnormality does not occur, and an emergency stop can also be performed if it is difficult to improve by operating condition control when the abnormality occurs.

  This will be described in detail with reference to FIG. The temperature detection means 105 can be provided at the raw material gas inlet part a and the raw material gas outlet part b in the reforming catalyst part 102a (catalyst) of the catalyst storage case 78a. FIG. 6 shows an example in which the temperature detection means 105 is provided at the source gas outlet b. The reforming catalyst portion 102a of the catalyst storage case 78a is configured by partitioning the inside of the catalyst storage case 78a with a mesh and storing the catalyst between the meshes, and the inlet side where the source gas of the catalyst is introduced is the source gas inlet portion. The outlet side from which the source gas is led out is a source gas outlet b.

  The temperature of the raw material gas inlet a of the catalyst has a great influence on the catalyst performance and life. For example, in a reforming catalyst, a temperature fluctuation exceeding an allowable range may occur in the catalyst housing case depending on the operating state of the solid oxide fuel cell, and the temperature fluctuation of the raw material gas inlet a of the catalyst is excessive due to this temperature fluctuation. When the temperature rises, it may cause carbon deposition. Therefore, in the present invention, when the temperature of the raw material gas inlet part a in the catalyst of the catalyst storage case 78a is higher than the set temperature range, the controller 130 supplies the water supply amount to the water vaporization part 109a of the catalyst storage case 78a. Control to increase.

  For example, under normal conditions, S / C, which is the ratio of water vapor to carbon in the raw material gas, is set to about 1.5 to 3.5, but the temperature of the raw material gas inlet a is higher than the set temperature range. At the time of detection, control is performed so that the S / C is about 2.5 to 4.5 by increasing the amount of water to the water vaporization unit 109a.

  By increasing the amount of water supplied for reforming in this way, the temperature of the raw material gas inlet part a of the adjacent catalyst is lowered by the endotherm accompanying water vaporization in the water vaporization part 109a and supplied to the catalyst. By reducing the mixed gas temperature, carbon deposition can be prevented.

  Also, when it is detected that the temperature of the catalyst source gas outlet b is deviating from the set temperature range, the operating condition control is performed so that the temperature of the catalyst source gas outlet b falls within the set temperature range, or Stop operation. For example, when the temperature of the raw material gas outlet b is lower than the set temperature range, the control device 130 controls to increase the oxygen source to the catalyst.

For example, S / C is set to about 1.5 to 3.5 under normal conditions, but when it is detected that the temperature of the source gas outlet b is lower than the setting, S / C is set to 2.5 to Control is performed to be about 4.5. In order to increase the S / C, the amount of water to the water vaporization unit 109a is increased, but the temperature of the raw material gas outlet b may further decrease due to an increase in the heat of vaporization. Therefore, it is also possible to supply air as an oxygen source instead of increasing the amount of water vapor. In this case, O ₂ / C, which is the ratio of oxygen to carbon in the source gas, is set to about 0.1 to 1.0 so that backfire and carbon deposition do not occur.

  Thus, by increasing the amount of oxygen source to the catalyst, such as water vapor and air, the conversion rate of the reforming reaction can be increased, the amount of hydrocarbons supplied to the fuel cell can be reduced, and carbon deposition can be prevented. Can do. In addition, the said setting conditions are an example and a setting temperature range and a supply water amount setting value can be changed arbitrarily.

  Further, when the temperature of the raw material gas outlet b in the catalyst of the catalyst storage case 78a is lower than the set temperature range, the controller 130 controls the fuel utilization rate to be lowered. For example, the fuel utilization rate under normal conditions is set to about 60 to 90%, but when it is detected that the temperature of the source gas outlet b is lower than the setting, the fuel utilization rate is set to about 20 to 60%. Control is performed as follows. As a result, even when the same power generation amount is performed, the fuel utilization rate is low, so that more fuel supply is required than in normal conditions. However, the surplus fuel amount not used for power generation is usually 40 to 80% compared to 10 to 40%. Therefore, the amount of combustion heat increases, and the temperature of the catalyst storage case 78a can be raised.

  In this way, by controlling so as to reduce the utilization rate of the fuel used for power generation, the amount of surplus fuel increases, so the amount of combustion heat substantially increases, and combustion occurs from the outside of the catalyst storage case 78a. Heated by the gas, the temperature of the catalyst source gas outlet b can be raised. The above setting conditions are merely examples, and the set temperature range and the fuel utilization rate set value can be arbitrarily changed. The fuel utilization rate is defined as the ratio of the amount of fuel gas used for power generation to the total amount of fuel gas supplied.

  When the temperature on both sides of the raw material gas inlet part a and the raw material gas outlet part b in the catalyst is higher than the set temperature range, that is, when the temperature of the entire catalyst storage case 78a is high, the air utilization rate is lowered and is low. Is controlled by the control device 130 so as to increase the air utilization rate. When the temperature on both sides of the raw material gas inlet part a and the raw material gas outlet part b is higher than a predetermined upper limit value, control is performed to reduce the utilization rate of air used for power generation, and the supply amount of power generation air is increased. By cooling the entire fuel cell assembly, it is possible to reduce the temperature of each part and prevent excessive catalyst temperature rise. In addition, when the temperature of each part is lower than the predetermined lower limit value, control is performed to improve the utilization rate of air used for power generation, and the supply amount of power generation air is decreased to raise the temperature of the entire fuel cell assembly. It is possible to raise the temperature of each part and to prevent poor reforming and the like. The air utilization rate is defined as the ratio of the amount of air used for power generation to the total amount of air supplied.

  For example, the air utilization rate under normal conditions is set to about 20 to 40%, but when it is detected that the temperatures on both sides of the source gas inlet part a and the source gas outlet part b are higher than a predetermined upper limit value, Control is performed so that the air utilization rate is about 5 to 20%. Thereby, the whole fuel cell assembly can be cooled by the increase in heat transfer of air. Conversely, when it is detected that the temperatures on both sides of the source gas inlet part a and the source gas outlet part b are lower than a predetermined lower limit value, the air utilization rate is controlled to be about 35 to 60%. Thus, the entire fuel cell assembly can be heated by reducing the heat transfer of air.

  The pressure detection means can be provided in the same manner as the temperature detection means 105. However, as shown in FIG. 7, the reformed gas supply pipe 82a is drawn upward, and the pressure detection means 135 is provided at the tip. it can. According to such a pressure detection means 135, the pressure in the catalyst storage case 78a can be easily detected. When the pressure detected by the pressure detecting means 135 is higher than the set pressure range, the control device 130 controls the oxygen storage source such as water vapor or air to the catalyst in the catalyst storage case to increase. . Thereby, for example, when carbon deposition or the like occurs on the reforming catalyst and an increase in the pressure loss of the reforming unit is detected by the pressure detecting means as a precursor to the gas channel blockage, oxygen such as water or air is temporarily used. By increasing the amount of the source, it is possible to accelerate the gasification reaction of the precipitated carbon and the oxygen source and remove the precipitated carbon, thereby extending the catalyst life and ensuring the long-term reliability.

  Such a catalyst in the catalyst storage case 78a is replaced by a method described later when a certain time has elapsed or when the integrated flow rate of the raw material gas introduced into the catalyst storage case becomes constant. Furthermore, it is also replaced when a unique temperature distribution that indicates deterioration of the catalyst occurs. Further, by disposing an indicator for notifying the replacement timing of the catalyst storage case 78a where it is easily noticeable, deterioration of the fuel cell performance can be prevented. As described above, the exchange can be performed with the front heat insulation wall 10 or the rear heat insulation wall 11 removed.

  As shown in FIG. 3, the power generation unit 56c is substantially the same as the power generation unit 56a described above, and the power generation units 56b and 56d are disposed opposite to the power generation units 56a and 56c in the front-rear direction. Fuel gas supply pipes (not shown) connecting the catalyst storage cases 78b and 78d and the fuel gas cases 58b and 58d are arranged on the rear side, and the reformed gas supply pipes 82b and 82d are located below the catalyst storage case. And extends under the housing 2 and out of the housing 2.

  The to-be-reformed gas supply pipes 82 a to 82 d are connected to a to-be-reformed gas supply device 91 for supplying the to-be-reformed gas outside the housing 2. The reformed gas supply device 91 supplies the reformed gas to the reformed gas supply pipes 82a to 82d at a predetermined pressure.

  In the fuel cell assembly as described above, the gas to be reformed is supplied to the reforming cases 78a, 78b, 78c and 78d via the gas to be reformed supply pipes 82a, 82b, 82c and 82d, and the catalyst storage case 78a. , 78b, 78c and 78d, the fuel defined in the fuel gas cases 58a, 58b, 58c and 58d through the fuel gas supply pipes 80a, 80b, 80c and 80d after being reformed into hydrogen-rich fuel gas. It is supplied to the gas chamber and then supplied to the cell stacks 60a, 60b, 60c and 60d.

In each of the cell stacks 60a, 60b, 60c and 60d, at the oxygen electrode,
1 / 2O ₂ + 2e ⁻ → O ²⁻ (solid electrolyte)
The electrode reaction of
O ²⁻ (solid electrolyte) + H ₂ → H ₂ O + 2e ⁻
The electrode reaction is generated and power is generated.

  Fuel gas and air that have flown upward from the cell stacks 60a, 60b, 60c and 60d without being used for power generation are ignited by an ignition means (not shown) disposed in the power generation / combustion chamber 12 at the time of startup. It is ignited and burned. As is well known, the power generation / combustion chamber 12 has a high temperature of, for example, about 800 ° C. due to power generation in the cell stacks 60a, 60b, 60c and 60d, and also due to combustion of fuel gas and air. The catalyst storage cases 78a, 78b, 78c and 78d are disposed in the power generation / combustion chamber 12, and are positioned immediately above the cell stacks 60a, 60b, 60c and 60d, and are directly heated by the combustion flame. Thus, the high temperature generated in the power generation / combustion chamber 12 is effectively used for reforming the reformed gas.

  The combustion gas generated in the power generation / combustion chamber 12 flows into the discharge passage 30 from the discharge opening 42 formed in the heat exchanger 24, and flows through the discharge passage 30 extending in a zigzag shape. 50 is discharged through a discharge passage defined between the outer cylinder member 52 and the inner cylinder member 54. When the combustion gas flows through the discharge path in the double cylinder 50, air flows through the inflow path in the double cylinder 50, and heat exchange is performed between the combustion gas and air.

  Further, when the combustion gas is caused to flow in the exhaust passage 30 of the heat exchanger 24 in a zigzag manner, the air is caused to flow so as to face the inflow passage 32 of the heat exchanger 24 in a zigzag manner. Thus, heat is effectively exchanged between the combustion gas and air to preheat the air.

  When part or all of the cell stacks 60a, 60b, 60c and 60d deteriorates due to power generation over a long period of time, the front heat insulation wall 10 or the rear heat insulation wall 11 of the housing 2 is detached or opened. Part or all of the power generation units 56 a, 56 b, 56 c and 56 d are taken out from the housing 2.

  Then, replace some or all of the power generation units 56a, 56b, 56c and 56d with new ones, or only the cell stacks 60a, 60b, 60c and 60d in some or all of the power generation units 56a, 56b, 56c and 56d. May be replaced with a new one and mounted again at a required position in the housing 2. Even when it is necessary to replace the reforming catalyst stored in the catalyst storage cases 78a, 78b, 78c and 78d in some or all of the power generation units 56a, 56b, 56c and 56d, the power generation units 56a, 56b , 56c and 56d are removed from the housing 2, and the catalyst storage cases 78a, 78b, 78c and 78d in the power generation units 56a, 56b, 56c and 56d are replaced with new ones or catalyst storage cases. Only the reforming catalyst in 78a, 78b, 78c and 78d may be replaced with a new one.

  In order to be able to perform the replacement of the reforming catalyst in the catalyst storage cases 78a, 78b, 78c and 78d sufficiently easily, a part of the catalyst storage cases 78a, 78b, 78c and 78d can be opened and closed as desired. It can be put on the door.

  On the other hand, air is supplied to the inflow path 32 of the heat exchanger 24 through the inflow path defined in the inner cylinder member 54 of the double cylinder 50, and is preheated (heated) through the heat exchanger 24. Is temporarily stored in the air chamber 16 and supplied between the cell stacks of the combustion / power generation chamber 12 through the air introduction pipe 22. At this time, the air introduction pipe 22 passes through the combustion gas atmosphere that burns in the vicinity of the fuel gas passage 74 at the upper end of the fuel cell 62 of the cell stack 60. Accordingly, the preheated air in the air chamber 16 is further heated in the combustion region above the cell stack 60, and the air heated to a high temperature is supplied to the cell.

  During normal operation, air preheated by the heat exchanger 24 is introduced into the air chamber 16, and air is introduced from the air chamber 16 into the combustion / power generation chamber 12 using the air introduction pipe 22. When the temperature rises more than expected, the low-temperature air that has passed through the low-temperature gas supply pipe 18 that does not pass through the heat exchanger 24 is introduced into the air chamber 16 and preheated through the heat exchanger 24. And the air temperature of the air chamber 16 is reduced to some extent. By supplying this air between the power generation chambers 12, that is, between the cell stacks, air having a lower temperature than that during normal operation is introduced between the cell stacks. Therefore, a good fuel cell assembly that can appropriately control the temperature in the power generation chamber is provided.

  Moreover, since the air temperature in the air chamber 16 is mixed with the outside air supplied from the low temperature gas supply pipe 18 and the air preheated through the heat exchanger 24, the air temperature is not as low as room temperature. Even if the fuel cell 60 is supplied to the hot fuel cell 60, problems such as cracking of the fuel cell 60 and thermal shock destruction can be avoided, so that the deterioration of the function of the entire fuel cell can be suppressed and the life can be extended.

  Furthermore, by supplying the supply of the low temperature gas from the low temperature gas supply pipe 18 toward the center of the opening of the air supply pipe 22, the air heated from the heat exchangers on both sides is further directed to the center of the opening. The air supplied through the air supply pipe 22 to the center of the cell assembly that is most easily heated can be at the lowest temperature, and the temperature can be increased as the distance from the center increases. can do.

  Further, the right heat storage wall 44a, the left heat storage wall 44b, the front heat storage wall 44c and the rear heat storage wall 44d, the lower heat storage wall 44e, and the upper heat storage wall 44f are disposed in the housing 2 around the cell assembly. By arranging the upper heat insulating wall 4, the lower heat insulating wall 6, the right heat insulating wall 8, the left heat insulating wall 9, the front heat insulating wall 10 and the rear heat insulating wall 11, the high temperature heat around the cell is stored by the heat storage wall, The heat dissipation to the outside can be effectively suppressed together with the heat storage wall and the heat insulating material, and in the fuel cell assembly for distributed power generation, the power generation temperature is effectively reduced even during partial load operation with a small amount of heat generation. Can be maintained.

  In other words, the fuel cell assembly for distributed power generation is small because the power generation amount is small, and is self-sustaining in the normal operation and generates power effectively. However, if the power generation amount is reduced by reducing the fuel gas amount, In the present invention, the heat is effectively confined in the housing by the heat insulating wall, the high-temperature heat in the steady operation is absorbed by the heat storage wall, the partial load operation is performed, and the heat generation amount is reduced. When the temperature decreases, heat can be dissipated and the temperature inside the housing can be effectively maintained.

  In the present invention, the catalyst storage case may be provided other than above the cell stack.

  Further, in the above embodiment, a case has been described in which low temperature gas supply means is provided in the air chamber and air is supplied to the outer surface of the fuel cell by the air supply pipe. However, air is supplied to the inside of the fuel cell by the air supply pipe. Of course, it may be made to do. In this case, it goes without saying that an air electrode is formed inside the fuel cell and a fuel electrode is formed outside.

  Although the fuel cell assembly shown in FIGS. 1 to 7 has been described in the above embodiment, it is not particularly limited.

Sectional drawing which shows suitable embodiment of the fuel cell assembly of this invention. The top view of FIG. FIG. 2 is a perspective view showing a power generation unit assembly used in the fuel cell assembly of FIG. 1. The perspective view which shows the electric power generation unit of FIG. Sectional drawing which shows the cell stack of FIG. It is a partial cross section figure which shows a catalyst storage case. It is a partial sectional view showing other catalyst storage cases.

Explanation of symbols

2: Housing 12: Power generation / combustion chamber 16: Air chamber (gas chamber)
22: Air supply pipe (gas supply pipe)
24: Heat exchangers 56a, 56b, 56c and 56d: Power generation units 58a, 58b, 58c and 58d: Fuel gas cases 60a, 60b, 60c and 60d: Cell stack 62: Fuel cell 78a, 78b, 78c and 78d: Catalyst Storage case 80a: Fuel gas supply pipe (gas outlet means)
82a: Reformed gas supply pipe (gas introduction means)
102a: reforming catalyst section 105: temperature detection means 109a: water vaporization mixing section 110a: reformed gas preheating section 130: control device 135: pressure detection means a: catalyst source gas inlet section b: catalyst source gas outlet section

Claims (14)

A housing defining a power generation chamber, a cell stack disposed in the housing, a catalyst storage case disposed in the housing, a gas introduction means attached to the catalyst storage case, and the catalyst storage case A reforming catalyst and / or a desulfurization catalyst is contained in the catalyst storage case, and is introduced into the catalyst storage case through the gas introduction means. The raw material gas is subjected to the action of the catalyst and supplied to the cell stack through the gas deriving means, and the catalyst storage case is provided with a temperature detecting means and / or a pressure detecting means, and the temperature detecting means and / or the pressure is provided. A fuel cell assembly comprising a detecting means connected to a measuring device outside the housing. 2. The fuel cell assembly according to claim 1, wherein the temperature detecting means is provided at a raw material gas inlet and / or a raw material gas outlet in the catalyst of the catalyst storage case. The catalyst storage case has a water vaporization unit, and when the temperature of the raw material gas inlet in the catalyst of the catalyst storage case is higher than a set temperature range, water supply to the water vaporization unit of the catalyst storage case 3. The fuel cell assembly according to claim 1, further comprising a control device that controls the amount to increase. A control device that controls to increase the amount of oxygen source supplied to the catalyst in the catalyst storage case when the temperature of the source gas outlet in the catalyst in the catalyst storage case is lower than a set temperature range; The fuel cell assembly according to claim 1, wherein the fuel cell assembly is a fuel cell assembly. 3. The fuel cell assembly according to claim 1, wherein surplus fuel gas that has not been used in the cell stack burns and the catalyst storage case is heated by the combustion gas. 6. The control device according to claim 5, further comprising a control device that controls the fuel utilization rate to be lowered when the temperature of the raw material gas outlet in the catalyst of the catalyst storage case is lower than a set temperature range. Fuel cell assembly. When the temperature of the source gas inlet and the source gas outlet in the catalyst of the catalyst storage case is higher than the set temperature range, the air utilization rate is reduced, and when the temperature is lower than the set temperature range, the air usage rate is improved. The fuel cell assembly according to claim 1, further comprising a control device that controls the operation of the fuel cell assembly. A housing defining a power generation chamber, a cell stack disposed in the housing, a catalyst storage case disposed in the housing, a gas introduction means attached to the catalyst storage case, and the catalyst storage case A reforming catalyst and / or a desulfurization catalyst is contained in the catalyst storage case, and is introduced into the catalyst storage case through the gas introduction means. The raw material gas is acted on by the catalyst and supplied to the cell stack through the gas deriving means. The gas introducing means is provided with a pressure detecting means, and the pressure detecting means is connected to a measuring device outside the housing. When the pressure detected by the pressure detection means is higher than the set pressure range, the oxygen source supply amount to the catalyst in the catalyst storage case is increased. Fuel cell assembly, characterized by comprising a control device for controlling the so that. The fuel cell assembly according to any one of claims 1 to 8, wherein the catalyst storage case is exposed to a combustion flame of excess fuel gas. The fuel cell assembly according to any one of claims 1 to 9, wherein the catalyst storage case is substantially elongated and is positioned above the cell stack. The fuel cell assembly according to any one of claims 1 to 10, wherein the load fluctuates. 12. The fuel cell assembly according to claim 1, wherein the fuel cell assembly is used for distributed power generation. The fuel cell assembly according to any one of claims 1 to 12, wherein the fuel cell assembly is used for home use. The fuel cell assembly according to any one of claims 1 to 13, wherein the power generation temperature is 800 ° C or lower.

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