JP2014056737A - Fuel cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a solid oxide fuel cell module in which a passage for a fluid circulating between the inside and outside of the module has firm airtightness with respect to an ambient space and is also removably coupled to secure maintainability.SOLUTION: A first vent tube 5 is disposed on the outside of a first case 2 constituting the outermost side of a module, and a second vent tube 6 communicating with the first vent tube 5 is connected to a second case 3 disposed inside the first case 2 via an air gap 4. Then, the first vent tube 5 and the second vent tube 6 are coupled with a screw 9 by sandwiching sealing members 7, 8 between flange parts 5a, 6a bent inward of the first vent tube 5 and the second vent tube 6 and an outer peripheral edge part of a vent hole 2a formed in the first case 2.

Description

  The present invention relates to a fuel cell module including a power generation unit that generates power by a chemical reaction of fuel, and more particularly, to a passage structure that allows fluid to flow in an airtight manner inside and outside the fuel module.

  As a fuel cell system, for example, in a solid oxide fuel cell system (SOFC system), a power generation unit including a fuel cell stack that generates electricity by reacting a hydrogen-containing fuel and an oxidant (air), and the power generation unit as a casing The surplus hydrogen-containing fuel (off-gas) is burned inside and the combustion exhaust gas is purified by the catalyst part, and then the heat of the exhaust gas is recovered by a heat medium and released to the outside of the fuel cell system.

As a pipe connection structure in a fuel cell system, as shown in Patent Document 1, there is one that prevents leakage of gas flowing in two connected pipes to the outside of the pipe (atmosphere side).
On the other hand, as an SOFC system, in Patent Document 2, a space is formed between a first case that constitutes the outermost casing of the module and a second case that surrounds the power generation unit inside the module, and an oxidant is formed in the annular space. (Air) is taken in and supplied to the power generation section (cathode electrode) inside the second case, and the off-gas combustion exhaust gas generated inside the second case is passed through a pipe protruding through the annular space to the outside of the module. Are discharged.

JP 2009-197844 A JP 2011-222136 A JP 2010-192272 A

  In the case of the structure as in Patent Document 2, it is necessary to avoid leakage of exhaust gas and oxidant flowing in the piping to the atmosphere, and mixing of the exhaust gas and oxidant flowing in the annular space. Then, it can cope with the airtightness between the two fluids, but cannot cope with the airtightness between the three fluids.

  If the first case and the second case (pipe) are fixed by welding or the like, the sealing performance is secured, but the second case cannot be attached to and detached from the first case, which is disadvantageous in terms of maintenance. In addition, the manufacturing cost increases.

  Further, as in Patent Document 3, it is conceivable that a flange portion extending radially outward is formed at an end portion of the passage member outside the module, and the flange portions are fastened together via a seal member.

However, with this method, it is impossible to prevent the exhaust gas and oxidant in the module from leaking into the atmosphere through the screw holes penetrating the flange portion, and it is impossible to ensure good sealing performance.
Although the sealing property can be secured by making the wall thickness of the module so thick that the screw hole does not penetrate, the size and weight of the module are increased. Furthermore, it is also conceivable to close the screw hole by welding a cap nut to each screw fastening portion. Even in this case, it is possible to secure sealing performance, but a plurality of expensive cap nuts are required, and the Welding takes time, and an airtight inspection of the cap nut welded portion is required, resulting in high costs.

  The present invention has been made paying attention to such a conventional problem, and while ensuring the airtightness of the passage through which the fluid flows between the inside and the outside of the fuel module with the two spaces adjacent to the passage, An object of the present invention is to provide a fuel cell module having a configuration that can ensure maintainability and can be manufactured simply and at low cost.

In order to achieve the above object, a fuel cell module according to the present invention comprises:
A fuel cell module configured by enclosing a power generation unit that generates power by a chemical reaction of fuel in a casing, and a passage through which fluid flows between the inside and the outside of the fuel cell module A first passage that is disposed; and a second passage that communicates with the first passage and is disposed inside the housing. The outer member constituting the first passage and the second member An inner member constituting the passage is fastened via a seal member in an inner space of the first passage and the second passage, and the inner space of the first passage and the second passage and the inner space of the housing The space outside the two passages and the space outside the first passage are hermetically separated.

  In the first passage and the second passage, the outer member and the inner member constituting the first passage and the second passage are fastened through the seal member inside the passage, so that the fluid in the passage passes through the screw hole for fastening the passage. However, it does not leak out of the passage. Further, the space inside the passage, the space outside the passage inside the module, and the space outside the passage (atmosphere) outside the module are airtightly separated by fastening via a seal member inside the passage, and are in each of these spaces. The sealing function between the three fluids is ensured.

Moreover, the outermost housing | casing which comprises a module, a 2nd channel | path, and the member connected with this are detachable freely, and maintainability is securable.
Furthermore, expensive cap nuts and welding and airtight inspections at a plurality of locations are unnecessary, and the manufacturing cost can be reduced.

The figure which shows the outline of an example of the fuel cell module to which the channel | path structure which concerns on this invention is applied. The figure which shows the outline of another example of the fuel cell module to which the channel | path structure which concerns on this invention is applied. The figure which expands and shows the channel | path structure which concerns on 1st Embodiment applied to the fuel cell module of FIG. 1 or FIG. The figure which expands and shows the channel | path structure which concerns on 2nd Embodiment applied to the fuel cell module of FIG. 1 or FIG. The figure which expands and shows the channel | path structure which concerns on 3rd Embodiment applied to the fuel cell module of FIG. 1 or FIG. The figure which shows the outline of another example of the fuel cell module to which the channel | path structure which concerns on this invention is applied. The figure which expands and shows the channel | path structure which concerns on 4th Embodiment applied to the fuel cell module of FIG. The figure which expands and shows the channel | path structure which concerns on 5th Embodiment applied to the fuel cell module of FIG. The figure which expands and shows the channel | path structure which concerns on 6th Embodiment applied to the fuel cell module of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, a schematic configuration of the fuel cell module will be described.
1 and 2 schematically show an example of a solid oxide fuel cell module to which a passage structure according to the present invention is applied.

  The casing 1 includes a rectangular parallelepiped first case (outer shell member) 2 constituting the outermost side of the casing 1 and a rectangular parallelepiped second case housed in the first case 2 with a first gap 4 therebetween. And a case (inner shell member) 3. These cases 2 and 3 are made of metal. However, the second case may have a configuration in which at least one of both side surfaces in the longitudinal direction has an open end, and the open end is detachably and airtightly connected to the inner wall surface of the first case 2.

  In the second case 3, there are a plurality of cells that generate electric power by a chemical reaction between the hydrogen-containing fuel and the oxidant (air), and excess hydrogen is contained on one end (downstream end in the flow direction of the reaction gas) of the cells. A power generation unit 11 including an off-gas combustion unit that burns fuel (off-gas) and maintains the cell stack at a high temperature is housed.

In the fuel cell module shown in FIG. 1, a reformer 12 for reforming the hydrogen-containing fuel supplied from the fuel supply pipe 14 is housed in the second case 3 in the vicinity of the off-gas combustion unit of the power generation unit 11. The The reformed gas generated in the reformer 12 is supplied to the anode (fuel electrode) of the cell stack via the reformed gas passage 13.
As the hydrogen-containing fuel (raw fuel), for example, a hydrocarbon fuel is used. As the hydrocarbon fuel, a compound containing carbon and hydrogen in its molecule (which may contain other elements such as oxygen) or a mixture thereof is used. For example, hydrocarbons, alcohols, ethers And biofuels. Specific examples of hydrocarbons include methane, ethane, propane, butane, natural gas, LPG (liquefied petroleum gas), city gas, town gas, gasoline, naphtha, kerosene, and light oil. Examples of alcohols include methanol and ethanol. Examples of ethers include dimethyl ether. Examples of biofuels include biogas, bioethanol, biodiesel, and biojet.

  The reforming method in the reformer 12 is not particularly limited, and for example, steam reforming, partial oxidation reforming, autothermal reforming, and other reforming methods can be employed. When steam reforming is used, a water vaporization unit is provided in the reformer 12 (or separately from the reformer 12), and steam is generated by heating and vaporizing water supplied from the outside of the housing 1. .

  As shown in FIG. 2, the reformer does not have to be provided inside the housing 1. For example, there is a form in which a reformer is provided outside the housing 1 and the reformed fuel is supplied from the fuel supply pipe 14 to the power generation unit 11. Alternatively, there is a form in which hydrogen-rich gas that does not require reforming is supplied from the fuel supply pipe 14 to the power generation unit 11. Alternatively, a dehydrogenation discharge pipe for discharging the dehydrogenation product from the dehydrogenation reaction section and the dehydrogenation reaction section is further added between the fuel supply pipe 14 and the power generation section 11, and organic hydride is supplied from the fuel supply pipe 14. There is a form in which the hydrogen-rich gas generated by the dehydrogenation reaction is supplied to the power generation unit 11.

  An oxidant (air) is taken into the gap 4 between the first case 2 and the second case 3 from an oxidant introduction pipe 2 a connected by opening the bottom wall of the first case 2. The oxidant in the gap 4 is introduced into the second case 2 from the oxidant intake port 3a formed by opening the top wall of the second case 3, and the cathode (oxidant electrode) of the cell stack in the power generation unit 11 is introduced. ).

As shown in FIG. 1, a passage for discharging exhaust gas to the outside of the housing 1 is formed in the bottom wall of the second case 3.
Further, as shown in FIG. 2, instead of the bottom wall of the second case 3, a passage for discharging the exhaust gas to the outside of the housing 1 is formed in the exhaust gas box 15 provided at the lower end of the second case. Also good. Specifically, the lower end of the second case 3 is opened, and the exhaust gas box 15 is connected to the lower end of the second case 3. In the exhaust gas box 15, an exhaust gas inlet 15 a communicating with the lower end of the second case is opened on the upper wall, and a passage for discharging the exhaust gas to the outside of the housing 1 is formed on the bottom wall. In the following description, the bottom wall of the second case 3 can be read as the bottom wall of the exhaust gas box 15.

  In the fuel cell module having the housing structure shown above, the exhaust gas generated in the second case 3 is guided to the outside of the first case 2, and the exhaust gas guided to the outside of the first case 2 is separated from the atmosphere. In the state, a fluid passage for leading to an exhaust gas utilization process in the fuel cell system is formed as follows.

  1 or 2, the exhaust gas is discharged out of the first case 2 from the bottom wall of the second case 3 or the bottom wall of the exhaust gas box 15 through a passage passing through the gap 4, To do.

In this case, it is required to prevent the exhaust gas flowing in the passage and the oxidant flowing in the gap 4 from leaking into the atmosphere and mixing due to leakage between the exhaust gas and the oxidant.
In FIG. 1, the second case 3 (and the power generation unit and reformer housed therein) and in FIG. 2 the second case (and the power generation unit housed inside) and the exhaust gas box 15 connected thereto. It is required to ensure maintainability as a structure that can be freely attached to and detached from the first case 2.

FIG. 3 shows an enlarged view of the passage structure according to the first embodiment, which is configured to satisfy each of the above conditions.
A vent hole 2 b is opened in the bottom wall of the first case 2, and the upper end portion of the first vent pipe 5 is connected to the vent hole 2 b outside the first case 2.

  On the other hand, a second vent pipe 6 having an upper end connected to an exhaust gas outlet opening in the bottom wall of the second case 3 or the exhaust gas box 15 is disposed, and a lower end portion of the second vent pipe 6 is disposed inside the first case 2. To connect to the vent 2b.

Here, the upper end portion of the first vent pipe 5 and the lower end portion of the second vent pipe 6 are bent radially inward to form flange portions 5a and 6a.
The first seal member 7 and the second seal member 8 are respectively provided between the flange portions 5a and 6a of the first vent pipe 5 and the second vent pipe 6 and the outer peripheral edge of the vent hole 2b of the bottom wall of the first case 2. And are fastened with screws 9 through a plurality of screw holes formed in the circumferential direction.

  With such a passage structure, the exhaust gas generated in the second case 3 passes through the second vent pipe 6 and the first vent pipe 5 and is discharged to the outside of the first case 2, and the first vent pipe 5 or downstream thereof. After being purified by a catalyst part (not shown) interposed in a passage connected to the side, it is discharged into the atmosphere.

  A fastening portion between the first vent pipe 5 and the second vent pipe 6 is provided inside the vent pipes 5 and 6 and sealed by the first seal member 7 and the second seal member 8. The space inside the trachea 5 and the second vent pipe 6 and the space 4 are separated in an airtight manner, and the space between these both spaces and the outer space (atmosphere) of the first vent pipe 5 is also separated in an airtight manner. .

  Therefore, even if the exhaust gas flowing in the inner space of the first vent pipe 5 and the second vent pipe 6 leaks in the screw hole of the fastening portion, it can be prevented from leaking to the outside of the vent pipe, that is, to the atmosphere. Further, leakage of the oxidant flowing through the gap 4 into the atmosphere can be prevented, and leakage between the exhaust gas and the oxidant can also be prevented.

  Thereby, the fall of the power generation performance of the fuel cell module due to the leakage of the oxidant and the mixing accompanying the leakage between the exhaust gas and the oxidant can be suppressed. Further, the exhaust gas can be guided to an arbitrary place determined by the design without leaking the exhaust gas from the joint portion between the first case 2 and the first vent pipe 5. Examples of the arbitrary portion determined by the design include a ventilation port and a flue pipe. Moreover, when the heat exchange part 17 is provided downstream of the 1st ventilation pipe 5, since it can suppress that exhaust gas of high temperature leaks to the atmosphere from the connection part of the 1st case 2 and the 1st ventilation pipe 5, a heat recovery part The heat recovery efficiency from the exhaust gas in 17 can be increased.

  Moreover, since the 1st case 2 and the 2nd case 3 are fastened and detached freely with the screw | thread 9, maintenance property can be ensured simultaneously with the improvement of the said power generation efficiency and heat recovery efficiency. For example, at least one of the side walls or the upper wall of the rectangular parallelepiped first case 2 is a detachable lid member, and the second case 3 is pulled out from the first case 2 in the opening direction of the lid member. What is necessary is just to set it as the structure which can be inserted.

In addition, expensive cap nuts, welding at a plurality of locations, and airtight inspection are not required, and the manufacturing cost can be reduced.
In addition, the 2nd sealing member 8 for suppressing mixing with exhaust gas and an oxidizing material inside the 1st case 2 should just use cheap ceramic fiber etc. with a comparatively low airtight level. On the other hand, since it is necessary to more reliably prevent the exhaust gas and the oxidant from leaking to the outside of the first case 2, it is preferable to use a relatively expensive ceramic fiber having a high hermetic level as the first seal member 7.

FIG. 4 shows an enlarged view of the passage structure according to the second embodiment.
In the present embodiment, the vent hole 2b larger than the outer diameter of the first vent pipe 5 is formed in the first case 2 by burring. And the flange part 5a of the 1st ventilation pipe 5 formed similarly to 1st Embodiment is joined to the inner surface of the ventilation hole 2b, and a joining part periphery is outside the 1st ventilation pipe 5 (atmosphere side). Weld. The vent hole 2b is not limited to the burring process, and may be formed by a simple punching process.

  On the other hand, the flange portion 5a of the first vent pipe 5 and the flange portion 6a of the second vent pipe 6 are sandwiched between the second seal members 8 and fastened with screws 9 in a plurality of screw holes formed in the circumferential direction. To do.

  In the present embodiment, the first vent pipe 5 and the first case 2 are welded and integrated, and the fastening portion between the first vent pipe 5 and the second vent pipe 6 is connected to the vent pipes 5 and 6. By providing the passage structure sealed inside by the second seal member 8, the space between the inner space of the first vent pipe 2 and the second vent pipe and the gap 4 is hermetically separated. The space and the outer space (atmosphere) of the first vent pipe 5 are also airtightly separated.

  Therefore, as in the first embodiment, between the exhaust gas flowing through the inner space of the first vent pipe 5 and the second vent pipe 6, the oxidant flowing through the gap 4, and the atmosphere outside the first vent pipe 5 Leakage can be prevented, oxidant leakage or reduction in power generation performance of the fuel cell module due to mixing with exhaust gas can be suppressed, and heat recovery efficiency from exhaust gas can be improved.

  In this embodiment, although a welding process is required, only one place of welding is required, and the gap between the outer peripheral edge portion of the vent hole 2b of the first case 2 and the flange portion 5a of the first vent pipe 5 is relatively expensive. Since the first seal member 7 can be omitted, the manufacturing cost can be reduced.

  Further, since the first case 2 and the second case 3 are detachably fastened by screws 9, maintenance can be ensured, and expensive cap nuts, welding at a plurality of locations thereof, and airtight inspection are not required. Similarly, the manufacturing cost can be reduced.

FIG. 5 shows an enlarged view of the passage structure according to the third embodiment.
In the present embodiment, as in the first embodiment, the end surface of the first vent pipe 5 is abutted and joined to the bottom wall of the first case 2 in which the vent hole 2b is formed, and the outer peripheral edge portion of the joint portion is attached. Weld. Note that the end face is not limited to the cut face of the first vent pipe 5 as shown in FIG. 5, and may be a flange face extending radially outward.

  Then, the outer peripheral edge of the vent hole 2b of the bottom wall of the first case 2 integrated with the first vent pipe 5 and the flange portion 6a of the second vent pipe 6 are sandwiched between the second seal members 8, and the periphery of these parts. The screw 9 is tightened through a plurality of screw holes formed in the direction.

  Since the third embodiment has a structure in which the flange portion 5a of the first vent pipe 5 is replaced with the outer peripheral edge portion of the vent hole 2b of the bottom wall of the first case 2 in the second embodiment, the functions and effects are as follows. This is the same as in the second embodiment.

FIG. 6 shows an outline of a fuel cell module having an internal structure different from those in FIGS.
The power generation unit 11 and the reformer 12 are housed in the second case 2 in the same manner as in FIG. 1, but are disposed through the bottom wall of the first case 2 and the bottom wall of the second case 3. The oxidant is supplied to the cathode electrode of the cell stack in the power generation unit 11 through the oxidant introduction pipe 16. Further, the reformed gas reformed by the reformer 12 is led out to the gap 4 between the first case 2 and the second case 3 through the reformed gas outlet passage 18. Next, the reformed gas is led from the bottom in the second case 3 to the anode electrode of the cell stack of the power generation unit 11 through the plurality of reformed gas introduction holes 3b opened in the bottom wall of the second case 3.

  In the fuel cell module having such a structure, the off-gas exhaust gas generated in the upper part of the power generation unit 11 is guided to the outside of the first case 2 and purified by the catalyst unit (not shown), and then the fluid passage that is released into the atmosphere is as follows. To form.

In this embodiment, as shown in a dotted line Y portion in FIG. 6, the exhaust gas is discharged from the top wall of the second case 3 to the outside of the first case 2 through a passage that penetrates the gap 4.
In this case, similarly to the first to third embodiments, leakage of the exhaust gas and the reformed gas flowing in the gap 4 adjacent to the exhaust gas into the atmosphere, and mixing due to leakage between the exhaust gas and the reformed gas are prevented. It is required to do.

Similarly, it is required that the second case 3 (and the power generation unit and reformer housed therein) be configured to be detachable from the first case 2 to ensure maintenance.
FIG. 7 shows an enlarged view of the passage structure according to the fourth embodiment, which is configured to satisfy each of the above conditions.

  The structure of the fourth embodiment corresponds to the structure of the first embodiment. A vent hole 2c is opened in the top wall of the first case 2, and the vent hole 2c is formed outside the first case 2 with the first hole. 1 Connect the lower end of the vent pipe 5.

On the other hand, a second vent pipe 6 having a lower end connected to an exhaust gas outlet opening in the top wall of the second case 3 is disposed, and an upper end portion of the second vent pipe 6 is provided inside the first case 2 with a vent hole 2c. Connect to.
Here, the lower end portion of the first vent pipe 5 and the upper end portion of the second vent pipe 6 are bent radially inward to form flange portions 5b and 6b.

  The first seal member 7 and the second seal member 8 are sandwiched between the flange portions 5b and 6b of the first vent pipe 5 and the second vent pipe 6 and the outer peripheral edge of the vent hole 2c of the first case 2, respectively. Then, screws 9 are fastened to a plurality of screw holes formed in the circumferential direction.

  With such a passage structure, the exhaust gas generated in the second case 3 passes through the second vent pipe 6 and the first vent pipe 5 and is discharged to the outside of the first case 2, and the first vent pipe 5 or downstream thereof. After being purified by a catalyst part (not shown) interposed in a passage connected to the side, it is discharged into the atmosphere.

  And the fastening part of the 1st ventilation pipe 5 and the 2nd ventilation pipe 6 was provided inside these ventilation pipes 5 and 6, and it was set as the structure sealed with the 1st seal member 7 and the 2nd seal member 8, The inner space of the first vent pipe 2 and the second vent pipe and the space 4 are separated in an airtight manner, and the space between both the spaces and the outer space (atmosphere) of the first vent pipe 5 is also airtight. To be separated.

  Therefore, even if the exhaust gas flowing in the inner space of the first vent pipe 5 and the second vent pipe 6 leaks in the screw hole of the fastening portion, it can be prevented from leaking to the outside of the vent pipe, that is, to the atmosphere. Further, it is possible to prevent leakage between the exhaust gas flowing in the inner space of the first vent pipe 5 and the second vent pipe 6, the reformed gas flowing in the gap 4, and the atmosphere outside the first vent pipe 5, and the reforming Reduction in power generation performance of the fuel cell module due to gas leakage or mixing with exhaust gas can be suppressed. Moreover, when the heat exchange part 17 is provided downstream of the 1st ventilation pipe 5, since it can suppress that exhaust gas of high temperature leaks to the atmosphere from the connection part of the 1st case 2 and the 1st ventilation pipe 5, a heat recovery part The heat recovery efficiency from the exhaust gas in 17 can be increased.

Moreover, since the 1st case 2 and the 2nd case 3 are fastened and detached freely with the screw | thread 9, maintenance property can be ensured simultaneously with the improvement of the said power generation efficiency and heat recovery efficiency.
FIG. 8 shows a fifth embodiment corresponding to the second embodiment, and FIG. 9 shows a sixth embodiment corresponding to the third embodiment.

  In these fifth and sixth embodiments, a sealing function similar to that of the fourth embodiment is obtained, and the sealing function reduces the power generation performance of the fuel cell module due to leakage of reformed gas or mixing with exhaust gas. And the efficiency of heat recovery from exhaust gas can be improved.

  In addition, the first case 2 and the second case 3 are detachably fastened with screws 9, so that maintainability can be ensured and secured, and expensive cap nuts, and welding and airtight inspection at a plurality of locations are unnecessary. Similarly, the manufacturing cost can be reduced.

  On the other hand, as in the second and third embodiments, a welding process is required as compared with the fourth embodiment, but the outer peripheral edge of the vent hole 2c of the first case 2 and the flange portion 5b of the first vent pipe 5 It is possible to omit the relatively expensive first seal member 7 that seals the gap.

  As described above, in the embodiment shown in FIGS. 1 to 5, the three fluids that are separated in an airtight manner are exhaust gas, an oxidant, and the atmosphere, whereas in the embodiment shown in FIGS. The three fluids to be separated are exhaust gas, reformed gas (hydrogen-rich gas), and air. Moreover, you may apply to the channel | path which isolate | separates these other 3 fluids. Furthermore, in the above-described embodiment, the present invention is applied to a fluid passage through which fluid such as exhaust gas flows out of the fuel cell module. However, the present invention allows fluid such as gas fuel to flow into the fuel cell module. It can also be applied to passages.

  The illustrated embodiments are merely examples of the present invention, and the present invention includes various improvements and modifications made by those skilled in the art within the scope of the claims in addition to those directly shown by the described embodiments. It goes without saying that it is what you do.

  For example, in FIGS. 1, 2 and 6, the first case 2 and the second case 3 are illustrated as simple configurations. However, a partition plate is disposed inside the housing 1 to provide an oxidant channel and an exhaust gas channel. It can be arbitrarily formed. Depending on the flow path structure, the oxidant introduction pipes 2 a and 16 may be connected to a wall surface other than the lower wall surface of the housing 1. 1 and 2 show a form in which the first and second vent pipes are connected to the bottom walls of the first and second cases 2 and 3, but depending on the flow path structure inside the housing 1, Or you may connect in a side part. Similarly, FIG. 6 shows a form in which the first and second vent pipes are connected to the upper walls of the first and second cases 2 and 3, but depending on the flow channel structure inside the housing 1, May be linked.

  2 shows the embodiment in which the exhaust gas box 15 is connected to the lower end of the second case 3 in the fuel cell module that does not include the reformer. However, the fuel cell module that includes the reformer as shown in FIG. The exhaust gas box 15 may be connected to the lower end of the second case 3.

  6 shows a form in which the reformed gas flows through the gap 4. However, when the reformer is not provided inside the housing 1, the reformer gas is supplied to the power generation unit 11 by means other than the reformer. Hydrogen rich gas may be circulated.

  The catalyst part for purifying the exhaust gas is not particularly shown, but for example, inside the first vent pipe 5, downstream of the first vent pipe 5, inside the second vent pipe 6, or upstream of the second vent pipe. Can be provided.

DESCRIPTION OF SYMBOLS 1 ... Housing | casing 2 ... 1st case 2b, 2c ... Ventilation hole 3 ... 2nd case 3a ... Oxidant intake 4 ... Cavity 5 ... 1st ventilation pipe 5a, 5b ... Flange part 6 ... 2nd ventilation pipe 6a, 6b DESCRIPTION OF SYMBOLS ... Flange part 7 ... 1st sealing member 8 ... 2nd sealing member 11 ... Power generation part 12 ... Reformer 13 ... Reformed gas passage 14 ... Fuel supply pipe 15 ... Exhaust gas box 15a ... Exhaust gas inlet 16 ... Oxidant introducing pipe 17 ... Heat recovery section 18 ... Reformed gas outlet passage

Claims (8)

A fuel cell module configured by enclosing a power generation unit that generates power by a chemical reaction of fuel in a housing,
A passage for allowing fluid to flow between the inside and the outside of the fuel cell module is provided inside the housing in communication with the first passage disposed on the outside of the housing and the first passage. A second passage and an outer member constituting the first passage and an inner member constituting the second passage through a seal member in the inner space of the first passage and the second passage. Conclude,
A fuel cell module, wherein an inner space of the first passage and the second passage, a space outside the second passage inside the housing, and a space outside the first passage are hermetically separated. .   The outer member constituting the first passage and the inner member constituting the second passage are respectively a flange portion in which an end on the housing side is bent inward, and an outer peripheral edge portion of a vent hole opened in the housing The fuel cell module according to claim 1, wherein a screw member is screwed between each flange portion and an outer peripheral edge portion of the vent hole.   The outer member that constitutes the first passage and the inner member that constitutes the second passage are screw-fastened with flange portions, each having an end portion on the housing side bent inward, with a seal member interposed therebetween, and 2. The fuel cell module according to claim 1, wherein an outer periphery of an outer member constituting the first passage is joined to a peripheral portion of a vent hole opened in the housing, and the joined portion is welded.   A flange portion in which an end on the housing side of the inner member constituting the second passage is bent inward and an outer peripheral edge portion of a vent hole opened in the housing sandwich a seal member therebetween. The end of the outer member that constitutes the first passage outside the fastening portion is joined to the outer wall of the housing, and the joint is welded. A fuel cell module according to claim 1. The second passage is connected to a second casing containing the power generation unit inside the casing or a connecting body to the second casing,
The fluid flowing in the inner space of the first passage and the second passage is combustion exhaust gas of surplus fuel in the power generation unit, and the fluid flowing in the space outside the second passage inside the housing inside the housing. The fuel cell module according to any one of claims 1 to 4, wherein is an oxidant. The second passage is connected to a second casing containing the power generation unit and a reformer for reforming fuel inside the casing or a connection body to the second casing,
The fluid flowing in the inner space of the first passage and the second passage is combustion exhaust gas of surplus fuel in the power generation unit, and the fluid flowing in the space outside the second passage is reformed by the reformer. The fuel cell module according to any one of claims 1 to 4, wherein the fuel cell module is a quality gas.   The fuel cell module according to any one of claims 1 to 6, further comprising a heat recovery unit downstream of the first passage.   The fuel cell module according to any one of claims 1 to 7, wherein the fuel cell module is a solid oxide fuel cell module.