JP6596856B2 - Reformed water evaporator and power generator - Google Patents

Description

  The present invention relates to a reforming water evaporator that generates steam for reforming, and a power generation apparatus including a fuel cell module having the reforming water evaporator.

  As a configuration for reforming a hydrocarbon-based fuel such as natural gas or LPG and introducing it into a fuel electrode (anode) of a fuel cell, for example, Patent Document 1 discloses a multi-cylindrical combustion section, reforming section, and evaporation section. A configured fuel reforming water device is disclosed. Further, Patent Document 2 discloses a configuration in which steam is superheated by heat exchange between the steam discharged from the reforming water evaporator and the reformed gas at the reformer outlet before being introduced into the CO converter. Yes. In the case of the configurations described in these Patent Documents 1 and 2, in order to prevent pressure fluctuations such as bumping and evaporation vibration in the reforming water evaporator, the reforming water is absorbed into a water absorbing material such as metal felt or steel wool. Heats and produces water vapor.

JP 2007-55892 A JP 2003-192304 A

  By the way, in high-temperature fuel cells such as solid oxide fuel cells (SOFC) and molten carbonate fuel cells (MCFC), fuel cell stacks, reformers, air preheaters, reformed water evaporators, combustion, In some cases, a high-temperature fuel cell module is configured by surrounding the part with a heat insulating casing. In such a fuel cell module, it is important to optimize the installation efficiency of each device inside the heat insulating casing, and to reduce the size and cost of the entire module. Furthermore, it is also necessary to reduce the heat radiation to the outside in order not to reduce the thermal efficiency in the high temperature heat insulation casing.

  However, when the combustion part, the reforming part, and the evaporation part are configured in a multi-cylindrical shape as in Patent Document 1, the structure and heat transfer of each part are complicated, making it difficult to design and manufacture, and the manufacturing cost increases. . In addition, in the configurations of Patent Documents 1 and 2, the reformer and the reformed water evaporator are configured as a cylindrical integrated type. Therefore, such a cylindrical composite device has poor installation efficiency inside the heat insulating casing of the fuel cell module described above, and the entire module is enlarged, and the thermal efficiency in the heat insulating casing is optimized. It is also difficult.

  The present invention has been made in consideration of the above-described conventional problems, and even when a high-temperature fuel cell module is configured, a reformed water evaporator that can be reduced in size and cost, and It aims at providing the electric power generating apparatus provided with the fuel cell module which has this reformed water evaporator.

  A reforming water evaporator according to the present invention is provided in a fuel cell module surrounded by a heat insulating casing, and generates reforming steam to be supplied to a reformer that reforms fuel introduced into a fuel cell stack. A reformed water evaporator, wherein a water vapor generating space is formed inside a box, a water spray pipe for sprinkling reformed water introduced from the outside of the heat insulating housing in the water vapor generating space, and the box A water absorption part capable of absorbing water sprayed from the water spray pipe is provided, and the reformed water sprayed on the water absorption part is heated by receiving heat generated in the heat insulating casing. And a heat transfer plate to be evaporated.

  The power generator according to the present invention includes a fuel cell stack, a reformer that reforms fuel introduced into the fuel cell stack, and reforming water that generates reforming steam to be supplied to the reformer. A power generator including a fuel cell module having an evaporator and a heat insulating casing surrounding the fuel cell stack, the reformer, and the reformed water evaporator, wherein the reformed water evaporator generates steam A box having a space formed therein, a water spray pipe for sprinkling reformed water introduced from the outside of the heat insulating housing in the water vapor generating space, and forming one wall surface of the box, and from the water spray pipe A water absorption part capable of absorbing the sprinkled water is provided, and includes a heat transfer plate that receives the heat generated in the heat insulating casing and heats and evaporates the reformed water sprayed on the water absorption part. And

  According to such a configuration, since the reforming water evaporator has a box shape by a box, the installation efficiency inside the heat insulating casing forming the fuel cell module is good. Therefore, the fuel cell module can be easily disposed at a desired position and the occupied area is small, and the fuel cell module can be downsized. Further, since the reforming water evaporator can be installed at a desired position in the high-temperature fuel cell module, the thermal efficiency in the heat insulating casing can be easily improved. Furthermore, the reforming water evaporator has a simple structure in which a water spray pipe is arranged inside the box and a water absorption part is provided on the inner surface of the heat transfer plate that is one wall surface of the box. Easy and low manufacturing cost. Moreover, since the water absorbing portion is provided on the surface of the heat transfer plate that evaporates the reforming water, evaporation vibration can be prevented and the reforming water diffuses smoothly, so that the evaporation is stabilized.

  In the reformed water evaporator according to the present invention, when the water absorption part is a metal felt or a metal fabric laid on the inner surface of the heat transfer plate, the water absorbed smoothly from the water sprayed from the water spray pipe. Diffusion and evaporation vibration can be prevented more reliably, and the heat transfer area is dramatically increased, so that the reforming water evaporator can be further downsized.

  In the reformed water evaporator according to the present invention, when the bottom surface of the box is formed by the heat transfer plate, and the water spray pipe is disposed above the heat transfer plate, a heat transfer plate is provided. A heat insulating structure can be constructed between the bottom surface side of the box body and the top surface side of the box body provided with the water spray pipe, and the heat received by the heat transfer plate is radiated from the top surface side of the box body to the outside. This can be suppressed.

  In the reformed water evaporator according to the present invention, the water spray pipe has a discharge hole for discharging the reformed water toward a water absorption portion provided in the heat transfer plate, and the discharge hole is the water spray pipe. A plurality of them may be provided along the longitudinal direction. Then, the reformed water can be dispersed and dispersed toward the water absorption part.

  In the power generator according to the present invention, the reforming water evaporator includes a bottom surface of the box formed by the heat transfer plate, and the water spray pipe is disposed above the heat transfer plate. The hot plate may be installed above the fuel cell stack with the outer surface of the hot plate facing the upper surface of the fuel cell stack. Then, the bottom surface of the box body becomes the heating surface, and the reformed water is introduced and sprinkled from the sprinkler pipe on the top surface side of the box body, so that the temperature of the top surface of the box body is lowered, and from the top of the heat insulating housing to the outside Heat dissipation can be reduced.

  According to the present invention, the fuel cell module can be downsized, and the reforming water evaporator and the fuel cell module can be easily designed and manufactured, so that the manufacturing cost can be reduced.

FIG. 1 is a block diagram illustrating a configuration of a power generation device including a fuel cell module according to an embodiment of the present invention. FIG. 2 is a perspective view showing a configuration example of a fuel cell module including a reforming water evaporator according to an embodiment of the present invention. 3 is a configuration diagram of a reforming water evaporator according to an embodiment of the present invention, FIG. 3 (A) is a plan view, FIG. 3 (B) is a front view, and FIG. C) is a side view. FIG. 4 is an explanatory view showing the internal structure of the reforming water evaporator, FIG. 4 (A) is a plan view, FIG. 4 (B) is a front sectional view, and FIG. FIG. FIG. 5 is a diagram illustrating an installation example of the discharge holes provided in the water spray pipe. FIG. 6 is a cross-sectional explanatory diagram for explaining a state where water is sprayed from the discharge hole provided in the water spray pipe to the water absorption portion and the heat transfer plate.

  Hereinafter, preferred embodiments of the reformed water evaporator according to the present invention will be described in detail with reference to the accompanying drawings with reference to preferred embodiments in relation to a fuel cell module and a power generation device including the reformed water evaporator. To do.

  First, the overall configuration of the power generation device 12 including the fuel cell module 10 will be described with reference to FIG. FIG. 1 is a block diagram illustrating a configuration of a power generation device 12 including a fuel cell module 10 according to an embodiment of the present invention.

  As shown in FIG. 1, the power generator 12 includes a fuel cell module 10 in which a fuel cell stack 14 is provided inside a heat insulating housing 16, fuel supply lines LF <b> 1 and LF <b> 2 that supply fuel and air to the fuel cell module 10, and Air supply lines LA1 and LA2, a hot water heat exchanger 18 that produces hot water using exhaust heat from the fuel cell module 10, and water for generating reforming steam used in the fuel cell module 10 are stored. It is comprised as a cogeneration system provided with the condensed water tank 20 to do.

  The fuel cell module 10 includes a fuel cell stack 14, a reformer 22, an air preheater 24, and a reformed water evaporator 26, and includes a heat insulating casing 16 that defines these heat insulating members in a box shape. It is installed inside (high temperature chamber). A general heat insulating material such as glass wool may be used as the heat insulating member. However, the fuel cell module 10 can be configured more compactly by using a board-shaped high-performance heat insulating material.

  The fuel cell stack 14 has a known configuration in which a plurality of rectangular flat power generation cells that generate power by reacting fuel introduced from the fuel supply line LF2 and air introduced from the air supply line LA2 are stacked. In the case of the present embodiment, the fuel cell stack 14 is constituted by a solid oxide fuel cell (SOFC) in which ion conductive ceramics are interposed as an electrolyte between a fuel electrode (anode) 14a and an air electrode (cathode) 14b. is doing. When the solid oxide fuel cell is configured by a flat stack stack, the fuel cell stack 14 can be configured compactly, and the power generation output per volume can be increased. Other high-temperature fuel cells such as a molten carbonate fuel cell (MCFC) may be used as the fuel cell stack 14. On the side of the fuel cell stack 14, a heater 28 for raising the temperature is installed.

  The raw fuel (for example, hydrocarbon fuel such as natural gas, LPG or city gas) from the fuel supply line LF1 is converted into a reformed fuel containing hydrogen and carbon monoxide via the desulfurizer 30 and the reformer 22, The fuel supply line LF2 introduces the fuel electrode 14a. The reformer 22 may have a known configuration, and various reforming catalysts are provided therein. The reforming water evaporator 26 evaporates the water (reformed water) sent from the flocculated water tank 20 that stores the flocculated water from the hot water heat exchanger 18 to generate steam for reforming. The steam (reforming steam) generated by the reforming water evaporator 26 is introduced from the steam supply line LW into the fuel supply line LF1 immediately before being introduced into the reformer 22, and then introduced into the reformer 22. . As a result, the fuel is mixed with the steam having a high temperature in the reforming water evaporator 26 and heated to, for example, about 300 ° C. and then introduced into the reformer 22 where the temperature rises to about 700 ° C. Steam reforming becomes reformed fuel.

  Air from the air supply line LA1 is introduced into the air preheater 24 by the blower 32, preheated to a desired temperature (for example, about 650 to 700 ° C.), and then introduced from the air supply line LA2 to the air electrode 14b. The

  The exhaust gas discharged from the fuel cell stack 14 is sent to the hot water heat exchanger 18 from the exhaust gas line LG. The hot water heat exchanger 18 produces hot water by heating the water supplied from the water storage tank 36 with the exhaust gas from the exhaust gas line LG, and the produced hot water is returned to the water storage tank 36. In the water storage tank 36, makeup water is supplied and warm water is taken out. Further, the exhaust gas that has passed through the hot water heat exchanger 18 is condensed and removed by the condensed water tank 20 and exhausted. The condensed water is supplied to the reforming water evaporator 26 as reforming water. The condensed water tank 20 is provided with a level meter, and makeup water is supplied when the water is below a certain level. Thereby, unnecessary gas and excess water are exhausted and drained.

  Next, a specific configuration example of the fuel cell module 10 constituting the power generation device 12 as described above will be described.

  FIG. 2 is a perspective view showing a configuration example of the fuel cell module 10 including the reforming water evaporator 26 according to the embodiment of the present invention. In the following, for the fuel cell module 10 and the reforming water evaporator 26, the front side in FIG. 2 is referred to as the front side (front side), the back side is referred to as the rear side (back side), and the left-right direction is the width direction (left-right width direction). ), The height direction will be referred to as the vertical direction.

  As shown in FIG. 2, in this embodiment, a fuel cell module 10 having a set of four units in which four fuel cell stacks 14 are provided in one heat insulating casing 16 is used. In the fuel cell module 10, two fuel cell stacks 14 are placed on the upper shelf 40a and the lower shelf 40b of the shelf device 40 installed in the heat insulating casing 16, and arranged in two rows and two columns in front view. It has become. Hereinafter, such a set of four fuel cell stacks 14 may be collectively described as the fuel cell stack 14.

  In the fuel cell module 10, a reformer evaporator 26 having a flat box shape is installed above the fuel cell stack 14 placed on the shelf device 40, and surrounds the three surfaces of the back surface and the left and right side surfaces of the fuel cell stack 14. Thus, an air preheater 24 is installed.

  The air preheater 24 includes a main preheater 50 disposed on the back side of the fuel cell stack 14 and a pair of auxiliary preheaters 52 and 52 disposed on the left and right side surfaces of the fuel cell stack 14. The gate shape covers the three surfaces of the fuel cell stack 14. The main preheater 50 and each auxiliary preheater 52 are connected to each other by rectangular tubular pipes provided on the upper and lower sides, respectively, so that air can flow. The air preheater 24 is made of, for example, stainless steel. The inside of the main preheater 50 is partitioned into a front and rear two-layer first preheating part and a second preheating part on the back side and the front side by a flat partition along the vertical direction. Therefore, the air introduced into the air preheater 24 via the air supply line LA1 is transferred to the first preheater of the main preheater 50, the left and right auxiliary preheaters 52 and 52, and the second preheater of the main preheater 50. After sequentially flowing and heated to a desired temperature, the air is introduced from the air supply line LA2 to the air electrode 14b.

  In the fuel cell module 10 in the heat insulating casing 16, the reformer 22 and the air preheater 24 that require higher temperatures are disposed in the vicinity of the fuel cell stack 14, and the reformed water evaporation that requires lower temperatures is possible. The container 26 is disposed above the fuel cell stack 14. By disposing the reforming water evaporator 26 above the fuel cell stack 14, it is possible to efficiently receive the heat generated and raised by the reaction and radiation of the fuel cell stack 14 in the heat insulating casing 16. Thereby, the produced steam for reforming can be sufficiently heated to a desired superheated state.

  Next, a specific configuration example of the reforming water evaporator 26 will be described.

  3 is a configuration diagram of the reforming water evaporator 26 according to an embodiment of the present invention, FIG. 3 (A) is a plan view, FIG. 3 (B) is a front view, and FIG. (C) is a side view.

  As shown in FIGS. 3A to 3C, the reforming water evaporator 26 includes a flat rectangular parallelepiped box 60 having a hollow water vapor generation space 58 therein, and the box 60 as a fuel cell module. 10 and a mounting member 62 that serves as a bracket when installed on the vehicle.

  The box 60 has a configuration in which a metal plate such as stainless steel is formed in a box shape. An inlet pipe 64 for introducing the reforming water from the condensed water tank 20 into the steam generation space 58 is provided on one side surface (right side surface) which is a short side in a plan view of the box body 60 shown in FIG. It protrudes (see also FIG. 2). An outlet to which a steam supply line LW for supplying the reforming steam generated in the steam generating space 58 to the reformer 22 is connected to one side surface (front) having a long side in plan view of the box 60. A tube 66 protrudes (see also FIG. 2).

  The attachment member 62 has a configuration in which a metal plate such as stainless steel is bent and formed into a flat gate shape as shown in FIG. The attachment member 62 includes a support plate 62a on which the lower surface of the box body 60 is placed and fixed, and attachment pieces 62b and 62b that are bent at the left and right ends of the support plate 62a. As shown in FIG. 2, each of the attachment pieces 62 b is fixed across the left and right auxiliary preheaters 52, 52 of the air preheater 24, so that the reforming water evaporator 26 is installed above the fuel cell stack 14. The By installing in this way, the thermal stress generated between the reforming water evaporator 26 and the fixed pipe connected to the reforming water evaporator 26 can be suppressed.

  4 is an explanatory view showing the internal structure of the reforming water evaporator 26, FIG. 4 (A) is a plan view, FIG. 4 (B) is a front sectional view, and FIG. 4 (C). These are side sectional views. In FIG. 4, the mounting member 62 is not shown.

  As shown in FIGS. 4A to 4C, the box 60 has a rectangular parallelepiped shape with an upper plate 60a serving as an upper surface, a bottom plate 60b serving as a bottom surface, and side plates 60c serving as four side surfaces, front, rear, left and right. The hollow water vapor generation space 58 is formed inside. The bottom plate 60b serving as the bottom surface of the water vapor generation space 58 is a portion disposed opposite to the upper surface of the fuel cell stack 14 in the fuel cell module 10, and receives heat generated and raised in the heat insulating casing 16 to generate water vapor. It becomes a heat transfer plate (heat transfer surface, heating surface) 60b for heating the space 58 (see also FIG. 2).

  The heat transfer plate 60b is formed of a metal plate such as stainless steel as described above. Therefore, when the inner surface of the heat transfer plate 60b is formed with a smooth surface, water droplets remain on the surface of the heat transfer plate 60b heated to a high temperature without being in contact with the heat transfer plate 60b using water vapor as a film. It exists on the heat transfer plate 60b, and the evaporation rate may be slow. Then, the evaporation rate is not stabilized, pressure fluctuation (pulsation) occurs, the steam carbon ratio in reforming becomes unstable, and there is a concern that appropriate reforming conditions in the reformer 22 cannot be maintained. That is, in the reformed water evaporator 26 configured in a box shape as in this embodiment, in order to reduce the pressure fluctuation in the steam generation space 58, the reformed water is dispersedly introduced and bumping is performed. In order to prevent this, it is necessary to allow the reforming water to penetrate the surface of the heat transfer plate 60b and penetrate it widely.

  Therefore, in the reformed water evaporator 26 according to the present embodiment, the water spray pipe 68 capable of dispersing and discharging the reformed water is disposed inside the steam generation space 58, and heat transfer serving as the bottom surface of the steam generation space 58. The water absorption part 70 is provided in the inner surface (upper surface) of the board 60b (refer FIG. 4 (B) and FIG.4 (C)).

  The water sprinkling pipe 68 is connected to the inlet pipe 64 in the box body 60, and is a pipe that sprinkles the reformed water supplied from the condensed water tank 20 through the inlet pipe 64 in the steam generation space 58. The water spray pipe 68 is disposed in the water vapor generation space 58 above the heat transfer plate 60 b (the water absorption part 70).

  As shown in FIG. 5, a plurality (eight in FIG. 5) of discharge holes 68a are formed on the lower surface side of the water spray pipe 68 along the longitudinal direction (the flow direction of the reforming water). Each discharge hole 68 a is formed at a position shifted in the circumferential direction from each other in the longitudinal direction of the water spray pipe 68. Thus, the reformed water introduced into the water spray pipe 68 is dispersed from each discharge hole 68a toward the water absorption part 70 of the heat transfer plate 60b, and the surface (heat transfer surface) of the heat transfer plate 60b is widely used effectively. Can do. At this time, since each discharge hole 68a is formed toward the center of the circle of the water spray pipe 68, the reformed water can be sprayed more smoothly (see FIG. 6). For example, when the pressure of the reforming water at the inlet of the sprinkling pipe 68 is 1 kPa or more, preferably about 10 kPa, the distribution of the reforming water from each discharge hole 68a is improved, and smoother water spraying is possible. Of course, the arrangement and the number of the ejection holes 68a can be changed as appropriate. Although FIG. 5 illustrates a configuration in which eight discharge holes 68a are alternately arranged, the arrangement of the discharge holes 68a can be changed as appropriate depending on the operating conditions, such as four in the center. In FIG. 4, the discharge hole 68a is arranged in the upper part of the water vapor generation space 58, but this is for improving the distribution of the reformed water, and may be arranged in the lower part depending on the operating conditions. In addition, by setting the flow rate of the reforming water in the sprinkling pipe 68 to 1 m / s or less, it is possible to sufficiently ensure the distribution of the reforming water from each discharge hole 68a.

  In the present embodiment, the sprinkling pipe 68 of a cylindrical pipe is illustrated, but if the rectangular pipe shape, the hole processing of the discharge hole 68a is facilitated, and the discharge hole 68a having a smaller diameter can be formed. Further, as the water spray pipe 68, a spray nozzle may be used instead of the cylindrical pipe or the rectangular pipe. Here, the structure in which the reforming water discharge portion (the water spray pipe 68 in the present embodiment) is installed or brought into contact with the upper surface 60a of the box body 60 can reduce the temperature of the upper surface 60a, thereby releasing the fuel cell module 10. The heat efficiency can be improved by reducing the amount of heat.

  The heat transfer plate 60b forms the bottom surface of the box body 60, and is a portion that heats and evaporates the reformed water sprayed from the sprinkler pipe 68 disposed above it to generate reforming steam. is there. The heat transfer plate 60b is finely processed on the inner surface, and a water absorbing portion 70 is provided thereon. The fine processing in this case may be formed, for example, by forming grooves of 1 mm or less in a cross shape with a pitch of 1 mm or less, or by knurling.

  In the case of the present embodiment, a metal felt such as stainless steel is spread on the surface of the heat transfer plate 60b as the water absorbing portion 70. As a result, when the reformed water is sprinkled from the sprinkling pipe 68 to the water absorption part 70, it is absorbed here and penetrates a wide area, and at the same time, it is heated and evaporated in a large heat transfer area by heat from the heat transfer plate 60b. The generated reforming steam flows from the outlet pipe 66 to the steam supply line LW and is introduced into the reformer 22.

  As the water absorption part 70, it is good also as a structure which can absorb a modified water widely only by microfabrication of the heat exchanger plate 60b, without providing a metal felt. Further, a metal fabric or the like may be used instead of the metal felt. That is, the water absorption part 70 should just be the structure which can be diffused and osmose | permeated widely using the capillarity phenomenon etc. for the reformed water sprayed from the water spray pipe 68, and liquids, such as a porous shape and a fine shape, permeate. Any structure may be used as long as it has a structure, and the heat transfer plate 60b may be a separate structure or an integral structure.

  As described above, according to the reformed water evaporator 26 according to the present embodiment, the box 60 in which the steam generation space 58 is formed and the reformed water introduced from the outside of the heat insulating casing 16 are steam-generated. A water sprinkling pipe 68 that sprinkles water in the space 58 and a bottom surface that is one wall surface of the box body 60 are formed, and a water absorbing portion 70 that can absorb water sprinkled from the water sprinkling pipe 68 is provided. And a heat transfer plate 60b that heats and evaporates the reformed water sprayed on the water absorption part 70 in response to the heat generated.

  Thus, since the reforming water evaporator 26 has a box shape formed by the box body 60, the installation efficiency inside the heat insulating casing 16 forming the fuel cell module 10 is good. Therefore, the fuel cell module 10 can be easily disposed at a desired position and the occupied area is small, and the fuel cell module 10 can be downsized. In addition, since the reforming water evaporator 26 can be installed at a desired position in the high-temperature fuel cell module 10, the thermal efficiency in the heat insulating casing 16 can be easily improved. Furthermore, the reforming water evaporator 26 has a simple structure in which a water spray pipe 68 is disposed inside the box body 60, and a metal felt is provided as a water absorbing portion 70 on the inner surface of the heat transfer plate 60 b that is one wall surface of the box body 60. Since it consists of a structure, design and manufacture are easy and manufacturing cost is low. Moreover, since the water absorbing portion 70 is provided on the surface of the heat transfer plate 60b that evaporates the reforming water, evaporation vibration (pulsation) can be prevented, and the reforming water diffuses smoothly, so that the evaporation is stabilized. At this time, since the metal felt is used as the water absorbing portion 70, the heat transfer area is remarkably increased, and the reformed water evaporator 26 can be further downsized.

  By the way, when the reforming steam and the hydrocarbon-based raw fuel are introduced into the reformer 22, if the reforming steam condenses and adheres to the reforming catalyst, it causes deterioration of the reforming catalyst. Therefore, it is necessary to set the overheated state at, for example, 180 ° C. or higher, desirably 200 ° C. or higher so that the reforming water vapor does not condense after the reforming water vapor and raw fuel mixed from the reforming water evaporator 26 are mixed. More desirably, when it is introduced into the reformer 22 at 300 to 500 ° C., the heat exchange amount necessary for the reformer 22 can be reduced. Here, when the temperature is set to 500 ° C. or higher, an inexpensive stainless steel member such as SUS304 may cause the constituent material Cr or the like to elute into the modified water. However, the impurity elution can be prevented by setting the temperature to 500 ° C. or lower. . As described in Patent Documents 1 and 2, the reformed water and the raw fuel can be mixed and introduced into the reformed water evaporator. However, the amount of heat for heating the raw fuel is required, and the heat transfer area is reduced. There is a need to enlarge. On the other hand, since only the reforming water is introduced into the reforming water evaporator 26 according to the present embodiment to perform the evaporation heat transfer, the heat transfer coefficient becomes higher than the heating of the gaseous hydrocarbon raw fuel. There is an advantage that a necessary heat transfer area can be reduced. Moreover, in the case of the present embodiment, since the water absorption part 70 is provided on the surface of the heat transfer plate 60b of the reforming water evaporator 26, a sufficient heat transfer area can be secured while reducing the size of the structure, and a desired The reforming steam that has become overheated can be efficiently generated.

  Further, the power generation device 12 according to the present embodiment includes the fuel cell module 10 having such a reformed water evaporator 26, a fuel cell stack 14, and a heat insulating casing 16 surrounding them. In this power generation device 12, the reformed water evaporator 26 is installed above the fuel cell stack 14, so that the heat that has risen in the heat insulating casing 16 can be efficiently received by the reformed water evaporator 26. . Therefore, the reforming steam can be smoothly heated to a desired superheated state. In addition, since the reformed water evaporator 26 can reduce heat radiation from the upper part of the heat insulating casing 16 to the outside, it is possible to maintain heat self-supporting in the module. Thereby, the fall of the fuel utilization rate in the fuel cell stack 14 is prevented, and the power generation efficiency of the entire apparatus can be maintained.

  At this time, in the reformed water evaporator 26 according to the present embodiment, the bottom surface of the box body 60 is formed by the heat transfer plate 60b, and the water spray pipe 68 is disposed above the heat transfer plate 60b. In addition, the reforming water evaporator 26 is installed above the fuel cell stack 14 with the outer surface of the heat transfer plate 60 b facing the upper surface of the fuel cell stack 14. As a result, the bottom surface (heat transfer plate 60b) of the box body 60 serves as a heating surface, and the reforming water is introduced and sprinkled from the water spray pipe 68 on the top surface (ceiling surface) side of the box body 60. A heat insulating structure can be built inside to lower the temperature of the upper surface, and heat radiation from the upper part of the heat insulating housing 16 to the outside can be further reduced.

  It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that the present invention can be freely changed without departing from the gist of the present invention.

  For example, in the above-described embodiment, the configuration in which the fuel cell stacks 14 are used as one set is illustrated. However, the number of the fuel cell stacks 14 can be changed as appropriate. Further, the fuel cell stack 14 may have a configuration in which one or a plurality of cylindrical power generation cells are provided instead of the rectangular laminated shape.

DESCRIPTION OF SYMBOLS 10 Fuel cell module 12 Power generation device 14 Fuel cell stack 14a Fuel electrode 14b Air electrode 16 Heat insulation housing 22 Reformer 24 Air preheater 26 Reformed water evaporator 58 Steam generation space 60 Box 60a Top plate 60b Bottom plate (Heat transfer) Board)
60c Side plate 62 Mounting member 64 Inlet pipe 66 Outlet pipe 68 Sprinkling pipe 68a Discharge hole 70 Water absorption part LA1, LA2 Air supply line LF1, LF2 Fuel supply line LW Water vapor supply line

Claims (5)

A reforming water evaporator that is provided in a fuel cell module surrounded by a heat insulating casing and generates reforming steam to be supplied to a reformer that reforms fuel introduced into the fuel cell stack,
A box that is formed and used above the fuel cell stack in a state where a water vapor generation space is formed inside and a bottom surface of the space is opposed to the upper surface of the fuel cell stack ;
A sprinkler pipe for sprinkling reformed water introduced from the outside of the heat insulating housing in the steam generation space,
The reformed water that forms the bottom surface of the box body and is provided with a water absorption portion capable of absorbing water sprayed from the water spray pipe, and receives heat generated in the heat insulating casing and is sprinkled into the water absorption portion. A heat transfer plate that heats and evaporates,
Equipped with a,
The water spray pipe is installed along the longitudinal direction of the water absorption part by being installed above the heat transfer plate,
The water spray pipe, reforming, characterized in Rukoto a discharge hole for discharging reformed water toward the water absorbing portion provided on the heat transfer plate, Yusuke plurality along the longitudinal direction of the diverging water tube Water evaporator. The reformed water evaporator according to claim 1, wherein
The water-absorbing part is a metal felt or metal fabric laid on the inner surface of the heat transfer plate. The reformed water evaporator according to claim 1 or 2,
The watering pipe is used by being installed on the upper surface of the box,
The box body, the upper plate of the box body forming the upper surface, the reforming water evaporator, wherein Rukoto installed exposed to the heat insulating housing. A fuel cell stack;
A reformer for reforming the fuel introduced into the fuel cell stack;
A reforming water evaporator for generating reforming steam to be supplied to the reformer;
A heat insulating enclosure surrounding the fuel cell stack, the reformer and the reformed water evaporator;
A power generation device including a fuel cell module having
The reformed water evaporator has a box that is installed above the fuel cell stack in a state where a steam generation space is formed inside and the bottom surface of the reformed water evaporator is opposed to the upper surface of the fuel cell stack ;
A sprinkler pipe for sprinkling reformed water introduced from the outside of the heat insulating housing in the steam generation space,
The reformed water that forms the bottom surface of the box body and is provided with a water absorption portion capable of absorbing water sprayed from the water spray pipe, and receives heat generated in the heat insulating casing and is sprinkled into the water absorption portion. A heat transfer plate that evaporates by heating ,
The water spray pipe is installed along the longitudinal direction of the water absorption part by being installed above the heat transfer plate,
The water spray pipe, the power generation device according to claim Rukoto a discharge hole for discharging reformed water toward the water absorbing portion provided on the heat transfer plate, Yusuke plurality along the longitudinal direction of the diverging water tube . The power generator according to claim 4,
The watering pipe is installed on the upper surface of the box,
The power generator according to claim 1, wherein an upper plate of the box forming the upper surface is exposed in the heat insulating casing.

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