JP5791071B2 - Solid oxide fuel cell system - Google Patents

Description

  The present invention relates to a solid oxide fuel cell system that generates power by oxidizing and reducing fuel gas and oxidant generated by reforming raw fuel.

  Conventionally, a solid oxide fuel cell system using a solid oxide fuel cell is known (for example, refer to Patent Document 1). The solid oxide fuel cell system includes a fuel cell stack for generating power by oxidation and reduction of fuel gas and oxidant, a heat exchanger for exchanging heat between the exhaust gas from the fuel cell stack and water, and a heat The hot water storage tank for storing the hot water after replacement | exchange, and the hot water storage water circulation channel for circulating water between a heat exchanger and a hot water storage tank are provided.

  The heat exchanger includes a heat exchanger main body and a plurality of partition plates arranged at intervals in the heat exchanger main body. The plurality of partition plates alternately define a plurality of first channels through which exhaust gas from the fuel cell stack flows and a plurality of second channels through which water from the hot water circulation channel flows. An exhaust gas inflow portion communicated with each upstream side of the plurality of first flow paths and an outflow manifold communicated with each downstream side of the plurality of second flow paths are provided at the upper end portion of the heat exchanger body. An exhaust gas outlet that communicates with each downstream side of the plurality of first flow paths and an inflow that communicates with each upstream side of the plurality of second flow paths at the lower end of the heat exchanger body And a manifold. The inflow manifold and the outflow manifold are provided through the plurality of first and second flow paths in the arrangement direction of the plurality of partition plates.

  Exhaust gas from the fuel cell stack flows into the plurality of first flow paths from the exhaust gas inflow part, flows downward through the plurality of first flow paths, and is then discharged to the atmosphere from the exhaust gas outflow part. Further, water from the hot water storage circulation flow path flows into the plurality of second flow paths from the inflow manifold, flows out through the plurality of second flow paths, then flows out from the outflow manifold, and is stored in the hot water storage tank. . Thereby, heat exchange is performed between the exhaust gas flowing through the plurality of first flow paths and the water flowing through the plurality of second flow paths.

JP 2007-273252 A

  However, the conventional solid oxide fuel cell system described above has the following problems. There is a tendency for so-called air accumulation, in which air in the outflow manifold accumulates, in the upper part of the inner periphery of the outflow manifold. Since the high-temperature (for example, 250 ° C. or higher) exhaust gas from the fuel cell stack flows into the exhaust gas inflow portion of the heat exchanger body, the heat accumulated in the inner periphery of the outflow manifold is heated by the heat of the exhaust gas. . Due to the heat of the heated air, a part of the water flowing through the outflow manifold evaporates, whereby scale components (for example, calcium, silica, magnesium, etc.) dissolved in the water become scale. It may precipitate. If the scaled stone adheres to the outflow manifold, corrosion cracks may occur in the outflow manifold.

  Further, in the solid oxide fuel cell system of the type that condenses and recovers the water vapor contained in the exhaust gas flowing through the first flow path, when corrosion cracking occurs as described above, the water flowing in the outflow manifold is the first. There is a risk of leakage into the flow path. In this way, when leaking into the first flow path, the scales adhering to the outflow manifold will be mixed into the condensed water, and if this condensed water is recovered and reused, there will be a problem with the solid oxide fuel cell system. May occur.

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a solid oxide fuel cell system including a heat exchanger that can suppress the formation of scale stones in an outflow manifold.

In the solid oxide fuel cell system according to claim 1 of the present invention, a fuel cell stack for generating power by oxidation and reduction of fuel gas and oxidant, and heat from exhaust gas and water from the fuel cell stack. Solid oxidation comprising: a heat exchanger for exchanging; a hot water tank for storing hot water after heat exchange; and a hot water circulation path for circulating water between the heat exchanger and the hot water tank A fuel cell system,
The heat exchanger includes a heat exchanger main body and a plurality of partition plates arranged at intervals in the heat exchanger main body, and the plurality of partition plates are exhaust gas from the fuel cell stack. A plurality of first flow paths through which water flows, and a plurality of second flow paths through which water from the hot water storage water circulation flow path flows,
An exhaust gas inflow portion communicated with each upstream side of the plurality of first flow paths and an outflow manifold communicated with each downstream side of the plurality of second flow paths at an upper end portion of the heat exchanger body At the lower end of the heat exchanger main body, exhaust gas outlets communicating with the downstream sides of the plurality of first flow paths, and upstream positions of the plurality of second flow paths. Ri Contact provided with an inlet manifold communicating with the side,
The inflow manifold and the outflow manifold are provided so as to penetrate the plurality of first and second flow paths in the arrangement direction of the plurality of partition plates, in order to prevent air accumulation in the outflow manifold. The accumulation prevention member is arranged ,
The accumulation preventing member has a shape corresponding to a cross-sectional shape of an inner peripheral upper portion of the outflow manifold, and is disposed in an upper inner peripheral portion of the outflow manifold .

In the solid oxide fuel cell system according to claim 2 of the present invention, the accumulation preventing member is formed in an arc shape .

According to the solid oxide fuel cell system of the first aspect of the present invention, since the accumulation preventing member for preventing air accumulation is disposed inside the outflow manifold, the heat exchanger main body When high-temperature (for example, 250 ° C. or higher) exhaust gas flows into the exhaust gas inflow section, it is possible to prevent hot air from accumulating inside the outflow manifold due to the heat of the exhaust gas. As a result, the occurrence of scale stones in the outflow manifold can be suppressed, and the occurrence of corrosion cracks in the outflow manifold can be suppressed.
In addition, the accumulation preventing member has a shape corresponding to the cross-sectional shape of the inner peripheral upper portion of the outflow manifold, and is disposed on the inner peripheral upper portion of the outflow manifold. As a result, it is possible to prevent air accumulation in the outflow manifold more reliably.

In the solid oxide fuel cell system according to claim 2 of the present invention, the pool preventing member is formed in an arc shape, so that the inner peripheral upper portion of the outflow manifold is filled with the pool preventing member. become.

It is a block diagram which shows simply the structure of the solid oxide fuel cell system by one Embodiment of this invention. It is a perspective view which shows the heat exchanger of FIG. It is sectional drawing of the heat exchanger by the AA line in FIG. It is sectional drawing of the heat exchanger by the BB line in FIG. It is sectional drawing of the heat exchanger by CC line in FIG. It is sectional drawing which expands and shows the outflow manifold in FIG. It is a perspective view which shows the accumulation prevention member of FIG. It is a disassembled perspective view which shows the state which decomposed | disassembled the 1st partition plate and 2nd partition plate of FIG. It is a disassembled perspective view which shows the state which decomposed | disassembled the 1st partition plate and outflow manifold of FIG. It is sectional drawing of the heat exchanger in the solid oxide fuel cell system by 1st reference embodiment . It is sectional drawing of the outflow manifold by the DD line in FIG. It is sectional drawing of the heat exchanger in the solid oxide fuel cell system by 2nd reference embodiment .

Embodiments of a solid oxide fuel cell system according to the present invention will be described below with reference to the accompanying drawings.
[One Embodiment of the Present Invention]
First, a solid oxide fuel cell system according to an embodiment will be described with reference to FIGS. FIG. 1 is a block diagram schematically showing the configuration of a solid oxide fuel cell system according to an embodiment of the present invention, FIG. 2 is a perspective view showing the heat exchanger of FIG. 1, and FIG. 2 is a cross-sectional view of the heat exchanger taken along line AA in FIG. 2, FIG. 4 is a cross-sectional view of the heat exchanger taken along line BB in FIG. 2, and FIG. 6 is a cross-sectional view of the heat exchanger taken along line -C, FIG. 6 is an enlarged cross-sectional view showing the outflow manifold in FIG. 5, and FIG. 7 is a perspective view showing the pool preventing member in FIG. 8 is an exploded perspective view showing a state in which the first partition plate and the second partition plate in FIG. 3 are disassembled, and FIG. 9 is a state in which the first partition plate and the outflow manifold in FIG. 3 are disassembled. FIG.

  Referring to FIG. 1, the solid oxide fuel cell system of this embodiment includes a solid oxide fuel cell 2, a reformer 4, and an air preheater 6. The solid oxide fuel cell 2 includes a substantially rectangular parallelepiped fuel cell main body 8 and a fuel cell stack 10 for generating power by an electrochemical reaction. The fuel cell body 8 includes a heat shield wall 12, a high temperature space 14 is defined inside the heat shield wall 12, and the fuel cell stack 10 is disposed in the high temperature space 14. The fuel cell stack 10 includes a solid electrolyte 16 that conducts oxygen ions. For example, zirconia doped with yttria is used as the solid electrolyte 16. A fuel electrode (not shown) is provided on one side of the solid electrolyte 16 of the fuel cell stack 10, and an oxygen electrode (not shown) is provided on the other side.

  The introduction side of the fuel electrode side 18 of the fuel cell stack 10 is connected to the reformer 4 via a fuel gas supply line 20, and this reformer 4 is connected to the raw fuel gas via the raw fuel gas supply line 22. Is connected to a raw fuel gas supply source 24 (for example, a buried pipe or a storage tank). The raw fuel gas supply line 22 is provided with a flow rate control valve 26 for controlling the supply amount of the raw fuel gas. Further, the introduction side of the oxygen electrode side 28 of the fuel cell stack 10 is connected to an air preheater 6 for preheating air via an air supply line 30, and the air preheater 6 is connected to an air supply line 34. Via the air blower 36.

  A combustion chamber 38 is provided on each discharge side of the fuel electrode stack 18 on the fuel electrode side 18 and the oxygen electrode side 28, and the reaction fuel gas (including residual fuel gas) discharged from the fuel electrode side 18 and the oxygen electrode side 28. The air (including oxygen) discharged from the fuel is supplied to the combustion chamber 38 and burned. The combustion chamber 38 is connected to the air preheater 6 via an exhaust gas supply line 40, and an exhaust gas discharge line 42 is connected to the air preheater 6. Further, a heat exchanger 44 is disposed in the exhaust gas discharge line 42 and is opened to the atmosphere through the heat exchanger 44.

  The heat exchanger 44 is connected to a hot water circulation line 48 (which constitutes a hot water circulation path) from a hot water tank 46 (which constitutes a hot water tank). The hot water circulation line 48 stores the hot water in the hot water tank 46. A circulation pump 50 is provided for circulating the generated water through the hot water circulation line 48. The hot water storage tank 46 stores heat generated by the operation of the solid oxide fuel cell 2 as hot water. A water supply line 52 is connected to the hot water storage tank 46, and an open / close valve 54 for controlling the supply of water (tap water) is disposed in the water supply line 52. Hot water stored in the hot water storage tank 46 is discharged through a hot water supply line 56.

  Further, a condensed water recovery tank 58 is provided for recovering and storing condensed water obtained by condensing water vapor contained in the exhaust gas. The condensed water recovery tank 58 is connected to the heat exchanger 44 via the condensed water recovery line 60. The condensed water recovery tank 58 is connected to a condensed water supply line 62 for supplying condensed water to the reformer 4. The condensed water supply line 62 includes an impurity removing means 64 and a supply pump. 66 is disposed. The impurity removing means 64 is composed of, for example, an ion exchange membrane and removes impurities contained in the condensed water.

  The operation of this solid oxide fuel cell system is performed as follows. The raw fuel gas from the raw fuel gas supply source 24 is supplied to the reformer 4 together with condensed water described later through the raw fuel gas supply line 22. In the reformer 4, a part of the raw fuel gas and water (condensed water) undergo a reforming reaction to reform a part of the raw fuel gas, and the fuel gas generated by the reforming is The fuel gas is supplied to the fuel electrode side 18 of the fuel cell stack 10 through the fuel gas supply line 20. Further, the air from the blower 36 is supplied to the air preheater 6 through the air supply line 34, heat is exchanged with the exhaust gas in the air preheater 6 and heated, and then passed through the air supply line 30. It is fed to the oxygen electrode side 28 of the fuel cell stack 10.

  The fuel electrode side 18 of the fuel cell stack 10 oxidizes the reformed fuel gas, and the oxygen electrode side 28 reduces oxygen in the air. Electricity is generated by oxidation of the fuel electrode side 18 and reduction of the oxygen electrode side 28. Electricity is generated by chemical reaction. The electrochemical reaction in the solid oxide fuel cell 2 is performed at a high temperature of about 700 to 1000 ° C.

  The reaction fuel gas from the fuel electrode side 18 and the air from the oxygen electrode side 28 are respectively sent to the combustion chamber 38, and excess fuel gas is combusted using oxygen in the air. The exhaust gas from the combustion chamber 38 is sent to the air preheater 6 through the exhaust gas supply line 40, and is used for heat exchange with the air from the blower 36 in the air preheater 6, and through the exhaust gas discharge line 42, the heat exchanger. 44. In the heat exchanger 44, heat exchange is performed between the water supplied from the hot water storage tank 46 through the hot water circulation line 48 and the exhaust gas flowing through the exhaust gas discharge line 42. Water (hot water) heated by heat exchange is stored in the hot water storage tank 46 through the hot water circulation line 48 by the action of the circulation pump 50.

  Further, when the temperature of the exhaust gas is lowered to the dew point by heat exchange, the water vapor contained in the exhaust gas is condensed and recovered and stored in the condensed water recovery tank 58 through the condensed water recovery line 60, and the exhaust gas after the condensation recovery is discharged into the exhaust gas. It is discharged to the atmosphere through line 68. The condensed water stored in the condensed water recovery tank 58 is fed to the impurity removing means 64 through the condensed water feeding line 62, and impurities contained in the condensed water are removed by the impurity removing means 64. The condensed water after the impurities are removed is fed to the reformer 4 through the condensed water feeding line 62 by the action of the feeding pump 66.

  Next, the configuration of the heat exchanger 44 in the solid oxide fuel cell system according to the present embodiment will be described with reference to FIGS. The heat exchanger 44 includes a horizontally long base 70 and a heat exchanger main body 72 having a substantially rectangular parallelepiped shape standing above the base 70. One end portion of the base 70 extends outward (lateral direction) from the lower end portion of the heat exchanger main body 72, and an exhaust gas outflow pipe 74 extends upward at this one end portion. An exhaust gas passage (not shown) is formed inside the base 70, and the exhaust gas passage communicates with the exhaust gas outlet pipe 74.

  An exhaust gas inflow portion 76 and an exhaust gas outflow portion (not shown) that are opened in a rectangular shape are provided at the upper end and the lower end of the heat exchanger main body 72, respectively. A frame-shaped gas receiving portion 78 for covering the exhaust gas inflow portion 76 from the outside is provided at the upper end portion of the heat exchanger main body 72, and the exhaust gas inflow portion 76 of the heat exchanger main body 72 communicates with the exhaust gas exhaust line 42. Is done. Further, the exhaust gas outflow portion is communicated with the exhaust gas flow path in the base 70. In one side surface of the heat exchanger main body 72, a water inflow pipe 80 is provided to extend to the outside at the lower end portion on the one side end portion side, and a water outflow pipe 82 is provided to the outside on the upper end portion on the other side end portion side. Is provided. The water inflow pipe 80 and the water outflow pipe 82 are connected to the outflow side and the inflow side of the hot water storage tank 46 via the hot water storage water circulation line 48, respectively.

  A heat exchange space 84 is formed inside the heat exchanger main body 72, and a plurality of first partition plates 86 and second partition plates 88 are alternately arranged in the heat exchange space 84 at intervals. Has been. Each of the first partition plate 86 and the second partition plate 88 is configured by interposing a nickel brazing material between a pair of thin stainless steel plates and brazing and fixing the pair of stainless steel plates. By the plurality of first partition plates 86 and the second partition plates 88, a plurality of first flow paths 90 through which the exhaust gas from the exhaust gas discharge line 42 flows and a plurality of second channels through which water from the hot water storage water circulation line 48 flows. Are alternately defined.

  A circular inflow opening 94 is provided at the lower end on one side end of the first partition plate 86, and a circular outflow opening 96 is provided at the upper end on the other side end. (See FIG. 5).

  The upper end portion of the second partition plate 88 is fixed to the first partition plate 86 adjacent thereto by brazing (see FIGS. 4 and 5). Further, both end portions and lower end portions of the second partition plate 88 are brazed and fixed to the first partition plate 86 adjacent thereto. The upper end portion and the lower end portion of the second partition plate 88 respectively define the upper end portion and the lower end portion of the second flow path 92, and the both end portions of the second partition plate 88 are respectively defined as the second flow path. The both end portions of 92 are defined. The upper end of the second partition plate 88 extends substantially in the horizontal direction (see FIG. 5), and the other side end is brazed and fixed to the upper side of the outflow manifold 98 (described later) ( FIG. 8 and FIG. 9).

  By being configured as described above, the first flow paths 90 and the second flow paths 92 are alternately defined between the plurality of first partition plates 86 and second partition plates 88. In addition, each upstream side of the plurality of first flow paths 90 communicates with the exhaust gas inflow portion 76, and each downstream side thereof communicates with the exhaust gas outflow portion.

  An inflow manifold 102 is provided on the outer periphery of the inflow opening 94 of the first partition plate 86, and an outflow manifold 98 is provided on the outer periphery of the outflow opening 96. The upper part of the outflow manifold 98 is fixed by brazing between a pair of adjacent first partition plates 86, and the lower side part thereof is between the adjacent first partition plate 86 and the second partition plate 88. (See FIGS. 3, 8, and 9). The outflow manifold 98 communicates with each downstream side of the plurality of second flow paths 92, and the plurality of first flow paths 90 and the second flow paths 92 are arranged in the arrangement direction of the plurality of partition plates 86 and 88. And communicates with the water outflow pipe 82 of the heat exchanger main body 72.

  Between the pair of adjacent first partition plates 86, the outflow manifold 98 is enlarged in a predetermined direction (the direction of water flow in the outflow manifold 98). In relation to this, an accumulation preventing member 106 configured in an arc shape (half ring shape) is brazed and fixed to the inner peripheral upper portion 104 of the outflow manifold 98 (see FIGS. 3, 6, and 7). ). Since the cross-section of the accumulation preventing member 106 has a shape corresponding to the cross-sectional shape of the inner circumferential upper portion 104 of the outflow manifold 98, the inner circumferential upper portion 104 of the outflow manifold 98 is filled with the accumulation preventing member 106 almost without any gap. It becomes like.

  Similarly to the outflow manifold 98, the inflow manifold 102 communicates with each upstream side of the plurality of second flow paths 92, and the plurality of first flow paths 90 and the second flow paths 92 are connected to the plurality of second flow paths 92. The partition plates 86 and 88 extend in the arrangement direction and communicate with the water inflow pipe 80 of the heat exchanger main body 72.

  The heat exchange between the exhaust gas and water in the heat exchanger 44 described above will be described as follows. Exhaust gas from the exhaust gas discharge line 42 flows into the plurality of first flow paths 90 from the exhaust gas inflow portions 76 of the heat exchanger main body 72, and as indicated by white arrows in FIGS. One flow path 90 flows downward. After that, it flows out from the exhaust gas outflow part, flows through the exhaust gas flow path, and is discharged to the atmosphere through the exhaust gas outflow pipe 74. Further, the water from the hot water circulation line 48 flows into the inflow manifold 102 from the water inflow pipe 80 of the heat exchanger main body 72, and as shown by the black arrows in FIGS. 3 and 4, a plurality of second flow paths. It flows up 92. After that, it flows through the outflow manifold 98 and flows out from the water outflow pipe 82, and is stored in the hot water storage tank 46 through the hot water circulation line 48. As described above, the exhaust gas flows downward through the plurality of first flow paths 90 and the water flows upward through the plurality of second flow paths 92, whereby heat exchange is performed between the exhaust gas and water.

The heat exchanger 44 of the present embodiment has the following characteristics because the accumulation preventing member 106 is disposed on the inner peripheral upper portion 104 of the outflow manifold 98. When there is no accumulation preventing member 106 as in the prior art, a so-called air accumulation, in which the air in the outflow manifold 98 accumulates in the inner peripheral upper portion 104 of the outflow manifold 98 occurs. On the other hand, in the heat exchanger 44 of the present embodiment provided with the accumulation preventing member 106, there is substantially no space in which the air is accumulated in the inner peripheral upper portion 104 of the outflow manifold 98. Air is prevented from accumulating at 104. Therefore, when high-temperature (for example, 250 ° C. or higher) exhaust gas flows into the exhaust gas inflow portion 76 of the heat exchanger main body 72, the heat of the exhaust gas causes high-temperature air to accumulate in the inner peripheral upper portion 104 of the outflow manifold 98. Can be prevented. As a result, the occurrence of scale stones in the outflow manifold 98 can be suppressed, and the occurrence of corrosion cracks in the outflow manifold 98 can be suppressed.
[ First Reference Embodiment ]
Next, the solid oxide fuel cell system of the first reference embodiment will be described with reference to FIGS. 10 and 11. In the above-described embodiment , air is not accumulated in the inner peripheral upper portion 104 of the outflow manifold 98, whereas in the first reference embodiment , the air in the outflow manifold 98 is affected by the heat of the exhaust gas. By making it difficult to receive, the formation of scale stones in the outflow manifold 98 is suppressed. FIG. 10 is a cross-sectional view of the heat exchanger in the solid oxide fuel cell system according to the first reference embodiment , and FIG. 11 is a cross-sectional view of the outflow manifold taken along line DD in FIG. Note that in the present embodiment , the same reference numerals are given to substantially the same components as those in the above-described embodiment , and the description thereof is omitted.

In the solid oxide fuel cell system of the present embodiment , arc-shaped (half-ring) first and second surrounding portions 108 and 110 as the surrounding means are disposed in the first flow path 90. ing. The first surrounding portion 108 is disposed in the first flow path 90 so as to surround the upper side of the outer peripheral surface of the outflow manifold 98. Further, the second surrounding part 110 is disposed in the first flow path 90 so as to surround the lower side of the outer peripheral surface of the outflow manifold 98. Each of the first and second surrounding portions 108 and 110 is formed by projecting a part of the first partition plate 86A toward the first flow path 90 by pressing, and the first partition plate. It is configured integrally with 86A.

  Thus, since the upper and lower sides of the outer peripheral surface of the outflow manifold 98 are respectively surrounded by the first and second surrounding portions 108 and 110, the exhaust gas flowing from the exhaust gas inflow portion 76 is the first and second. The surrounding portions 108 and 110 prevent the flow to the outflow manifold 98 side, and the high temperature exhaust gas is prevented from contacting the outer peripheral surface of the outflow manifold 98. Thereby, it is possible to suppress the air accumulated in the inner peripheral upper portion 104 of the outflow manifold 98 from being heated, and hence it is possible to suppress the formation of scale stones in the outflow manifold 98, and The occurrence of corrosion cracking in 98 can be suppressed.

The surrounding portion 108 (110) may be configured in a ring shape, and the surrounding portion of the outflow manifold 98 may be surrounded by the surrounding portion 108 (110).
[ Second Reference Embodiment ]
Next, a solid oxide fuel cell system according to a second reference embodiment will be described with reference to FIG. FIG. 12 is a cross-sectional view of a heat exchanger in the solid oxide fuel cell system according to the second reference embodiment .

In the solid oxide fuel cell system according to the present embodiment , the first flow passage 90 is provided with a plate-shaped surrounding member 112 as the surrounding means. The surrounding member 112 is disposed in the first flow path 90 so as to surround the lower side of the outer peripheral surface of the outflow manifold 98, and is brazed and fixed between the first and second partition plates 86 and 88. ing.

  Thus, since the lower side of the outer peripheral surface of the outflow manifold 98 is covered by the surrounding member 112, the exhaust gas flowing in from the exhaust gas inflow portion 76 is discharged by the surrounding member 112 by the surrounding member 112, as in the second embodiment described above. The flow to the 98 side is suppressed, and the high temperature exhaust gas is prevented from contacting the outer peripheral surface of the outflow manifold 98. Thereby, it is possible to suppress the air accumulated in the inner peripheral upper portion 104 of the outflow manifold 98 from being heated, and hence it is possible to suppress the formation of scale stones in the outflow manifold 98, and The occurrence of corrosion cracking in 98 can be suppressed.

Having described an embodiment of a solid oxide fuel cell system according to the present invention, the present invention is not limited to such embodiments, and various modifications to modifications without departing from the scope of the present invention Is possible.

It should be noted that the technique according to one embodiment of the present invention (the accumulation preventing member 106) and the technique according to the first or second reference embodiment (the surrounding means 108, 110, 112) may be applied in combination.

DESCRIPTION OF SYMBOLS 10 Fuel cell stack 44, 44A, 44B Heat exchanger 46 Hot water storage tank 48 Hot water circulating line 72 Heat exchanger main body 76 Exhaust gas inflow part 86, 86A 1st partition plate 88 2nd partition plate 90 1st flow path 92 1st Two flow paths 98 Outflow manifold 102 Inflow manifold 106 Accumulation prevention member 108 First enclosure 110 Second enclosure 112 Enclosure

Claims (2)

A fuel cell stack for generating power by oxidizing and reducing fuel gas and oxidant, a heat exchanger for exchanging heat between the exhaust gas from the fuel cell stack and water, and for storing hot water after heat exchange A solid oxide fuel cell system comprising a hot water storage tank, and a hot water storage circulation path for circulating water between the heat exchanger and the hot water storage tank,
The heat exchanger includes a heat exchanger main body and a plurality of partition plates arranged at intervals in the heat exchanger main body, and the plurality of partition plates are exhaust gas from the fuel cell stack. A plurality of first flow paths through which water flows, and a plurality of second flow paths through which water from the hot water storage water circulation flow path flows,
An exhaust gas inflow portion communicated with each upstream side of the plurality of first flow paths and an outflow manifold communicated with each downstream side of the plurality of second flow paths at an upper end portion of the heat exchanger body At the lower end of the heat exchanger main body, exhaust gas outlets communicating with the downstream sides of the plurality of first flow paths, and upstream positions of the plurality of second flow paths. Ri Contact provided with an inlet manifold communicating with the side,
The inflow manifold and the outflow manifold are provided so as to penetrate the plurality of first and second flow paths in the arrangement direction of the plurality of partition plates, in order to prevent air accumulation in the outflow manifold. The accumulation prevention member is arranged ,
The solid oxide fuel cell system , wherein the accumulation preventing member has a shape corresponding to a cross-sectional shape of an inner peripheral upper portion of the outflow manifold, and is disposed in an upper inner peripheral portion of the outflow manifold . The solid oxide fuel cell system according to claim 1, wherein the accumulation preventing member is formed in an arc shape .

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