JP6821482B2 - Solid oxide fuel cell device - Google Patents

Description

The present invention relates to a fuel cell device. In particular, the present invention relates to a fuel cell apparatus using a solid oxide fuel cell that generates electricity by reacting a fuel gas obtained by reforming a raw material gas with an oxidant gas.

The solid oxide fuel cell (Solid Oxide Fuel Cell: also referred to as "SOFC") uses an oxide ion conductive solid electrolyte as an electrolyte, and a fuel cell with electrodes on both sides thereof is placed in a multi-module container. By disposing and supplying fuel gas to one electrode (fuel electrode) of the fuel cell and supplying oxidizing agent gas (hereinafter, also referred to as air or air for power generation) to the other electrode (air electrode). It is a device that extracts the power generated by the power generation reaction. It operates at a relatively high temperature of, for example, about 700 to 1000 ° C., as compared with other fuel cell devices such as a polymer electrolyte fuel cell device, and has higher overall energy efficiency than other fuel cell devices.

In such a solid oxide fuel cell device, for example, as described in Patent Document 1, the fuel gas and the air for power generation that did not contribute to power generation are burned above the fuel cell inside the module container. A combustion chamber is provided, and a reformer for steam reforming the raw material gas is provided above the combustion chamber. Then, the fuel gas reformed by the reformer is sent to the gas manifold provided below the fuel cell through the fuel gas supply pipe extending in the vertical direction on the side of the fuel cell, and is sent to the gas manifold. Is supplied to the fuel cell.

Here, Patent Document 1 discloses that the reformer is fixed to the top surface inside the module container. Further, in Patent Document 1, one side surface of the module container is provided with an opening for inserting a plurality of fuel cell cells, and the plurality of fuel cell cells are slidably inserted into the inside of the module container through the opening, and the opening is a lid. Air-sealed by. With such a configuration, the welding work procedure after accommodating the fuel cell is reduced and workability is reduced as compared with the case where a plurality of module container lids are welded and fixed around the plurality of fuel cell. Is improved.

In addition, when welding is performed on a module container, welding droplets (metals scattered during joining such as spatter) adhere to the surface of the fuel cell, and the fuel cell generates electricity at the portion where the welding droplets adhere. Is hindered, and the power generation performance of the fuel cell is deteriorated. As described above, if a plurality of fuel cell cells are slidably inserted into the module container and the opening is closed by the lid, the welding operation procedure after accommodating the fuel cell cells is reduced. , The risk of fuel cell contamination / deterioration due to welding droplets can be suppressed.

When assembling such a solid oxide fuel cell device, when the fuel cell is inserted into the module container, the fuel cell and the fuel gas supply pipe connecting the reformer and the gas manifold interfere with each other. Resulting in. Therefore, as in Patent Document 2, the fuel gas supply pipe is divided into upper and lower parts, the fuel cell is arranged in the module container, and then the fuel gas supply pipe divided by the pipe joint is connected. (For example, refer to the pipe joints of pipes 6A and 6B in the drawings of Patent Document 2). In this case, since the two divided fuel gas supply pipes are screwed and fixed to the pipe joint, the pipe joint has a complicated shape such as being threaded.

JP 2013-257984 Japanese Unexamined Patent Publication No. 2011-18456

However, commercially available pipe joints are not supposed to be used in a high temperature environment, and have lower heat resistance than fuel gas supply pipes and the like. Therefore, when the pipe joint receives the heat of the combustion chamber, the pipe joint deteriorates and the surface peels off in powder form. If such peeled powder adheres to the fuel cell, the fuel cell will be contaminated. Therefore, if a pipe joint having high heat resistance is manufactured and used separately, the cost becomes high.

Therefore, after a plurality of fuel cell cells are inserted into the module container, it is desirable to weld and join the divided fuel gas supply pipes without using a pipe joint from the viewpoint of pollution prevention and low cost. However, since the fuel gas supply pipes are welded to each other in the vicinity of a plurality of fuel cell cells stored in the module container, welding droplets adhere to the fuel cell cells, contaminating and deteriorating the fuel cell cells. There is a risk that it will end up.

Therefore, the present invention relates to a solid oxide fuel cell apparatus provided with a module container in which a reformer is fixed inside and a plurality of fuel cell cells are inserted through side openings, and the fuel cell is used when manufacturing a fuel cell module. It is an object of the present invention to provide a solid oxide fuel cell device for improving manufacturing easiness and further reducing the cost while suppressing pollution and deterioration of the fuel cell.

One aspect of the fuel cell device according to the present invention is a solid oxide fuel cell device including a plurality of fuel cell cells that generate power by a power generation reaction between a fuel gas and an oxidizing agent gas, and the plurality of fuel cell cells are used. A rectangular module container housed inside and having at least one side open, a module container lid covering one side, and a reformer fixed to the module container and arranged above the inside of the module container. A gas manifold provided below the inside of the module container to supply the fuel gas generated by the reformer to a plurality of fuel cell cells erected on the upper surface, and a reformer arranged and connected to one side surface. The first pipe that allows the fuel gas to flow out from the gas, the second pipe that is arranged on one side and allows the fuel gas to flow into the connected gas manifold, and the ends of the first pipe and the second pipe are inserted. It is provided with a connecting member for communicating the first pipe and the second pipe, and the connecting member is formed from a connecting member main body that shields the inside of the connecting member and a plurality of fuel cell cells, and a connecting member lid. Therefore, inside the connecting member, the first pipe and the second pipe are welded and joined to the connecting member main body.

Conventionally, in the case where the reformer is fixed above the inside of the module container and one side is open, a plurality of fuel cell cells having a gas manifold below are inserted into the module container and then connected to the reformer. The first pipe and the second pipe connected to the gas manifold were joined by a pipe joint. Since the first pipe and the second pipe are provided so as to hang down the sides of the aggregate of a plurality of fuel cell cells, the surface of the pipe joint deteriorates due to the influence of the generated heat of the fuel cell cells. It becomes powdery, and the powder may be scattered on the fuel cell, which may have an adverse effect.

Here, since the first pipe and the second pipe are connected in the vicinity of a plurality of fuel cell cells, if welding is attempted to join them without using a pipe joint, welding droplets adhere to the fuel cell. It causes pollution and deterioration of the fuel cell. In addition, when welding work is performed so as to prevent welding droplets from adhering to the fuel cell, it is inferior from the viewpoint of workability, and there is a risk that the operator may come into contact with the fuel cell and be damaged or deteriorated. was there.

On the other hand, in the embodiment of the present invention, the ends of the first pipe and the second pipe are inserted into the connecting member that communicates the gas flow paths so as to be continuous, and the inside of the connecting member and the second The first pipe and the end of the second pipe are connected. As a result, the first pipe and the second pipe can be communicated with each other without using a pipe joint.

In particular, in the embodiment of the present invention, since the connecting member is provided so as to shield the inside of the connecting member from the fuel cell, the first pipe and the second pipe are provided inside the connecting member whose circumference is covered. The end of the pipe and the inside of the connecting member can be welded together. Therefore, it is possible to suppress the welding droplets from scattering to the fuel cell and prevent the fuel cell from being contaminated.

In particular, in the mode according to the present invention, since one side surface of the module container is open and the first pipe and the second pipe are also located on one side surface side, the welding work from the outside of the module container is performed from the open side surface. Can be done. As a result, workability can be improved while suppressing the risk of the operator coming into contact with the fuel cell.

As described above, in the embodiment of the present invention, it is possible to improve the ease of manufacture and further reduce the cost while suppressing the contamination and deterioration of the fuel cell during the manufacture of the fuel cell module.

Here, in the present specification, "communication" indicates a state in which fluids are connected so that they can flow. For example, even if the first pipe and the second pipe are not joined, it is sufficient that the fuel gas can flow through the connecting member.

Here, in the present specification, "welded joint" refers to integration in which heat and / or pressure is applied to a joint portion of two or more members, a filler metal is added if necessary, and the joint portion has continuity. It shows the state of being joined by the joining method which makes it one member. For example, fusion welding, pressure welding, and brazing are also included in "welding joints".

In one aspect of the present invention is also the connecting member main body is formed in a rectangular parallelepiped shape, the connecting member main body has an open surface on different sides to the side which is arranged a plurality of fuel cells, the open surface connecting member It is preferably covered with a lid.

According to this aspect, the entire surface of the rectangular parallelepiped connecting member main body is open. Welding work to the connecting member is performed from the outside of the module container, so workability is poor. However, since the entire surface of the connecting member body is open, welding work inside the connecting member from the outside of one side surface of the module container is easy. It becomes. That is, it is possible to suppress contamination and deterioration of the fuel cell while facilitating production.

Further, in one aspect of the present invention, it is preferable that the connecting member main body has an open surface on one side surface side.

In the joining work from other than one side, the joining tool (for example, a welding torch) may not reach and the welding work may become difficult. However, according to this aspect, since one open side surface of the module container and the open surface of the connecting member main body are on the same side, welding work from the outside of one side surface inside the connecting member main body becomes easy and workability is improved. To do.

In addition, since the connecting member main body is open only on the surfaces facing the fuel cell side surfaces, welding droplets adhere to the fuel cell cells during the welding work of the first pipe and the second pipe. This can be reliably prevented. Further, since the connecting member main body and the connecting member lid are located on one side surface, it is possible to prevent welding droplets from adhering to the fuel cell when the connecting member lid is welded to the connecting member main body. Contamination and deterioration can be suppressed.

Further, in one aspect of the present invention, the connecting member lid is provided inside the open surface of the connecting member main body, and the connecting member lid is provided on the main surface for closing the open surface and on the outer shell of the main surface. It is preferable to have a folded-back portion protruding to one side surface side of the outer surface, and the end portion on the open surface and the end portion on the folded-back portion are welded and joined.

According to this aspect, the end portion of the connecting portion main body and the end portion of the connecting portion lid body are welded and joined. That is, since each end is located on one side surface side, the connection portion main body and the connection portion lid can be joined from one side surface side. As a result, the welding work can be performed on one side surface, and it is possible to prevent welding droplets from adhering to the fuel cell during welding and joining, thereby improving workability and the fuel cell. It is possible to prevent pollution and deterioration of the fuel cell at the same time.

Further, in one aspect of the present invention, it is preferable that the flow path cross-sectional area of the connecting member is larger than the flow path cross-sectional area of the first pipe and / or the second pipe.

According to this aspect, since the flow path cross-sectional area of the connecting member is larger than that of the fuel gas supply pipe, the mixing portion that makes the reforming variation and the supply amount variation inside the reformer uniform. Functions as. As a result, the fuel gas can be evenly supplied to the plurality of fuel cell cells. Further, even if the pressure fluctuates in the fuel gas supply pipe due to an abnormality of the fuel supply source or the like, the inside of the connecting member functions as a buffer, so that the fuel cell on the downstream side is not affected.

Further, in one aspect of the present invention, it is preferable that a combustion chamber is formed above the plurality of fuel cell cells, and the connecting member is located at the height of the combustion chamber.

According to this aspect, since the connecting member is located above the fuel cell, welding work can be performed on the connecting member at a position away from the fuel cell, and welding droplets are suppressed from adhering to the fuel cell. It becomes possible. In addition, the fuel gas circulating inside the connecting member can effectively receive heat from the combustion chamber.

Further, in one aspect of the present invention, it is preferable that an insertion hole is formed in the main body of the connecting member, and the end of the first pipe and / or the second pipe is located inside the insertion hole.

According to this aspect, since the end of the fuel gas supply pipe is provided so as to project toward the inside of the connecting member main body, the fuel gas supply pipe and the insertion hole provided in the connecting member main body are provided inside the connecting member. It becomes easy to weld and join with the vicinity, and the manufacturing workability is improved.

Further, in one aspect of the present invention, a hydrogenated desulfurizer that supplies a part of the fuel gas generated by the reformer is provided, and a pipe for the hydrogenated desulfurizer that supplies the fuel gas to the hydrogenated desulfurizer is connected. It is preferably joined to the member body or the connecting member lid.

When the pipe for the hydrogenated desulfurizer is attached to the reformer, it is necessary to take out the reformed fuel gas, so that it must be arranged on the downstream side of the reformer. However, depending on the shape of the reformer and the flow rate of the gas flowing inside the reformer, the fuel gas may not sufficiently flow into the hydrogenation desulfurization pipe. According to this aspect, since the hydrogenated desulfurizer pipe is provided in the connecting member after passing through the reformer, the gas can be reliably supplied regardless of the gas flow rate and the shape of the reformer.

In a solid oxide fuel cell device equipped with a module container in which a reformer is fixed inside and a plurality of fuel cell cells are inserted through side openings, the fuel cell cells are polluted and deteriorated during fuel cell module manufacturing. It is possible to provide a solid oxide fuel cell device for improving manufacturing ease and further reducing the cost while suppressing the pressure.

It is a perspective view which shows the fuel cell module in one Embodiment of this invention. It is a side sectional view which shows the fuel cell module which has the connection member in one Embodiment of this invention. It is a perspective view which shows the connection member in one Embodiment of this invention. It is a partial cross-sectional view which shows the connection member in one Embodiment of this invention. It is a partial cross-sectional view (A), (B) and (C) which shows the process of welding-connecting a connecting member and a fuel gas supply pipe in one Embodiment of this invention. It is an overall block diagram which shows the solid oxide fuel cell apparatus (SOFC) by one Example of this invention. FIG. 7 is a side sectional view showing a fuel cell module of a solid oxide fuel cell device according to an embodiment of the present invention. It is sectional drawing along the line III-III of FIG. It is an exploded perspective view of a module container and an air passage cover. It is a perspective view which shows the inner surface of the closed side plate which constitutes a module container. It is a perspective view which shows the periphery of the connecting member in an assembled state. It is a partial cross-sectional view which shows the fuel cell unit of the solid oxide fuel cell apparatus according to one Example of this invention. FIG. 7 is a side sectional view showing a fuel cell module of a solid oxide fuel cell device according to an embodiment of the present invention, similar to FIG. 7. FIG. 8 is a cross-sectional view taken along the line III-III of FIG. 7, similar to FIG.

Hereinafter, embodiments of the invention disclosed in the present specification will be described in detail with reference to the drawings. From the following description, many improvements and other embodiments of the present invention will be apparent to those skilled in the art. Therefore, the following description should be construed as an example only and is provided for the purpose of teaching those skilled in the art the best aspects of carrying out the present invention. The details of its structure and / or function can be substantially modified without departing from the spirit of the present invention.

FIG. 1 is a perspective view showing a height direction (H), a width direction (W), and a depth direction (L) of a fuel cell module 1002 having an open surface 1016 on one side surface, and FIG. 2 is a perspective view seen from the W direction. It is a partial cross-sectional view which shows the internal structure of a module container 1018.

First, an embodiment of the present invention will be described with reference to FIGS. 1 and 2. As shown in FIGS. 1 and 2, the fuel cell module 1002 has a plurality of fuel cell cells 1012 provided above the gas manifold 1004 provided inside the module container 1018, and is provided inside the module container 1018. It has a reformer 1024.

Raw fuel gas and steam are supplied to the reformer 1024 (not shown), and fuel gas is generated by a steam reforming reaction. As shown in FIG. 2, the fuel gas generated by the reformer 1024 passes through the fuel gas supply pipe 1006 and is supplied to the inside of the gas manifold 1004. The top surface of the gas manifold 1004 is composed of a lower support plate 1010 having through holes for supporting a plurality of fuel cell 1012s, and fuel is used inside the gas manifold 1004 closed by the lower support plate 1010. Gas is supplied to the plurality of fuel cell cells 1012.

Further, the power generation air (oxidizing agent gas) is supplied from the power generation air introduction pipe 1028 to the air passage 1034 formed between the inner wall of the air passage cover 1022 and the outer wall of the module container 1018. After that, the power generation air is supplied to the power generation chamber 1008 from the air outlet 1026 provided on the side surface of the module container 1018, and the fuel cell 1012 performs a power generation reaction with the supplied power generation air and the fuel gas. The power generation air and fuel gas that did not contribute to power generation are burned in the combustion chamber 1030 provided above and discharged to the outside of the module container 1018 from the exhaust passage 1032.

Here, as shown in FIG. 1, the rectangular parallelepiped module container 1018 is composed of a module container main body 1014 and a closing side plate (module container lid) 1020. Above the inside of the module container body 1014, a reformer 1024 extending in the longitudinal direction (L direction) of the module container body 1014 is fixed to the inner wall surface of the module container body 1014. Although the fixing structure in this embodiment is not shown, the reformer 1024 may be fixed to the inner wall surface of the module container main body 1014 in any way.

Further, as shown in FIGS. 1 and 2, the module container main body 1014 has an open one side surface 1016, and the module container main body is formed from the one side surface 1016 in a state where the fuel cell 1012 is arranged above the gas manifold 1004. It is slidably inserted inside the 1014 (black arrow in FIG. 2). After the fuel cell 1012 is arranged in the module container body 1014, one side surface 1016 of the module container body 1014 is closed by the closing side plate (module container lid) 1020 (black arrow in FIG. 1). Here, the module container main body 1014 and the closing side plate 1020 are joined by welding to keep the inside of the module container 1018 airtight.

After inserting the fuel cell 1012 into the module container body 1014, only the closing side plate (module container lid) 1020 needs to be welded to the module container body 1014, and after the fuel cell 1012 is stored inside. The welding work can be minimized, and the risk of welding droplets adhering to the fuel cell 1012 can be suppressed.

Further, as shown in FIGS. 1 and 2, the reformer 1024 and the gas manifold 1004 are connected by a fuel gas supply pipe 1006. The fuel gas supply pipe 1006 as a fuel gas passage hangs down between the closed side plate 1020 and the plurality of fuel cell 1012, bends near the bottom surface of the module container 1018, and is formed below the plurality of fuel cell 1012. It is connected to the gas manifold 1004.

The fuel gas supply pipe 1006 is divided into a first pipe 1006A connected to the reformer 1020 and a second pipe 1006B connected to the gas manifold 1004 (see FIG. 2). The first pipe 1006A and the second pipe 1006B are connected by a connecting member 1036 (described in detail later). The fuel gas that has passed through the first pipe 1006A passes through the inside of the connecting member 1036 and then flows into the gas manifold through the second pipe 1006B so that the fuel gas flowing inside communicates with the gas manifold ( (Dotted arrow in FIG. 2).

Next, the connecting member 1036 according to the embodiment of the present invention will be described with reference to FIGS. 3 to 5. FIG. 3 is a perspective view of the connecting member main body 1038 connected to the first pipe 1006A and the second pipe 1006B, and the connecting member lid 1040.

As shown in FIG. 3, the connecting member main body 1038 has a rectangular parallelepiped shape with one side open. Specifically, the connecting member main body 1038 has a top surface 1038A, a bottom surface 1038B, three side surface 1038C, and an open open surface 1038D. Further, an insertion hole 1038E into which the ends of the first pipe 1006A and the second pipe 1006B are inserted is formed in the top surface 1038A and the bottom surface 1038B.

Further, the connecting member lid body 1040 closes the open surface 1038D of the connecting member main body 1038. The connecting member lid body 1040 has a quadrilateral main body portion 1040A and a folded-back portion 1040B extending from the edge of the main body portion. The folded-back portion 1040B extends outward of the connecting member 1036.

The opening surface 1038D of the connecting member main body 1030 is closed by the connecting member lid 1040 after the ends of the first pipe 1006A and the second pipe 1006B are fixed to the insertion holes 1038E. As a result, the inside of the connecting member 1036 can be hermetically sealed, and the fuel gas flowing through the first pipe 1006A and the second pipe 1006B can be communicated with each other.

The connecting member 1036 is preferably made of the same material as the material constituting the module container 1018. As a result, it is possible to prevent the connecting member 1036 from being thermally deteriorated.

FIG. 4 is a partial cross-sectional view showing a state in which the first pipe 1006A and the second pipe 1006B and the connecting member 1036 are fixed. The first pipe 1006A and the second pipe 1006B are welded and fixed to the connecting member main body 1038, and the connecting member lid 1040 is also welded and joined to the connecting member main body 1038.

First, the first pipe 1006A is inserted into the insertion hole 1038E formed in the top surface 1038A. The insertion hole 1038E is formed so that the edge is bent at a right angle and extends in the internal direction of the connecting member 1036. Here, the end of the first pipe 1006A is inserted so as to protrude inward from the edge of the insertion hole 1038E, and the first pipe 1006A and the edge of the insertion hole 1038E are welded and joined ( The black part in FIG. 4). That is, since the end of the first pipe 1006A is formed so as to protrude inward from the edge of the insertion hole 1038E, the welding work between the first pipe 1006A and the insertion hole 1038E inside the connecting member main body 1038. Becomes easier.

Similarly, the second pipe 1006B is inserted into the insertion hole 1038E formed in the bottom surface 1038B. The insertion hole 1038E is formed so that the edge is bent at a right angle and extends in the internal direction of the connecting member 1036. Here, the end of the second pipe 1006B is inserted so as to protrude inward from the edge of the insertion hole 1038E, and the second pipe 1006B and the edge of the insertion hole 1038E are welded and joined ( The black part in FIG. 4). That is, since the end of the second pipe 1006B is formed so as to protrude inward from the edge of the insertion hole 1038E, the welding work between the second pipe 1006B and the insertion hole 1038E inside the connecting member main body 1038. Becomes easier.

In this way, the welding work between the first pipe 1006A and the second pipe 1006B and the edge of the insertion hole 1038E inside the connecting member 1036 becomes easy. Further, since welding is performed inside the connecting member 1038 whose circumference is covered other than the open surface 1038D, it is possible to suppress the scattering of droplets to the fuel cell 1012 side, improving workability and improving the workability of the scattered fuel cell 1012. Both pollution and deterioration can be achieved.

Although not shown in the present embodiment, it is also preferable to dispose a hydrogenation desulfurizer pipe for supplying hydrogen to the hydrogenation desulfurizer in the connecting member 1036. When the pipe for the hydrogenated desulfurizer is attached to the reformer 1024, it is necessary to take out the reformed fuel gas, and therefore it is necessary to dispose of it on the downstream side of the reformer 1024. However, depending on the shape of the reformer 1024 and the flow rate of the gas flowing inside, the fuel gas may not sufficiently flow into the hydrogenation desulfurizer piping. According to the present embodiment, since the hydrogenated desulfurizer pipe is provided in the connecting member 1036 after passing through the reformer 1024, the fuel gas is arranged in the hydrogenated desulfurizer regardless of the gas flow rate and the reformer shape. Can be supplied to. Further, according to the connecting member 1036 of the present embodiment, it is possible to prevent the scattering of welding droplets when welding the hydrogenation desulfurization pipe, so that the fuel cell 1012 can be attached while suppressing contamination and deterioration. It becomes. Any surface other than the fuel cell 1012 may be attached to the connecting member 1036.

Next, as shown in FIG. 4, the connecting member main body 1038 and the connecting member lid 1040 are welded and joined. The connecting member main body 1038 has an open surface 1038D on one side surface 1016 side of the module container 1018 (see FIG. 2), and the open surface 1038D is closed by the connecting member lid 1040. Here, the main body portion 1040A of the connecting member lid 1038 is arranged inside the open surface 1038D, and the end portion of the folded-back portion 1040B and the end portion of the open surface 1038D are arranged so as to coincide with each other. By welding and joining the end of the folded-back portion 1040B and the end of the open surface 1038D (black-painted portion in FIG. 4), the inside of the connecting member 1036 is hermetically sealed.

As described above, since the end portion of the open surface 1038 and the end portion of the folded portion 1040B are configured to coincide with each other on one side surface 1016, these welding operations are performed from the outside of one side surface 1011 of the module container 1018. It becomes possible to do it and workability is improved. Further, since the welding work can be performed on one side surface 1016 side, the connecting member 1036 can prevent the welding droplets during the welding work from adhering to the fuel cell.

Further, the inner diameter D3 of the connecting member 1036 is larger than the inner diameter D1 of the first pipe 1006A and the inner diameter D2 of the second pipe 1006B. That is, the flow path cross-sectional area of the connecting member 1036 is larger than the flow path cross-sectional area of the first pipe 1006A and the second pipe 1006B.

As a result, the fuel gas generated by the reformer 1024 is further mixed in the connecting member 1036 having a space wider than the pipeline, and the variation in the reforming of the fuel gas and the variation in the fuel gas supply amount are caused inside the connecting member 1036. Can be uniform. Further, even if the pressure fluctuates in the pipe due to an abnormality in the fuel gas supply or the like, the inside of the connecting member 1036 functions as a buffer, so that the influence does not affect the fuel cell 1012.

The inner diameters D1 and D2 of the first pipe 1006A and the second pipe 1006B may be smaller than the inner diameter D1 of the connecting member 1036, and the magnitude relationship between D1 and D2 may be adjusted as appropriate. Further, the size of the flow path cross-sectional area of the connecting member 1036 can be appropriately adjusted by the length of the folded-back portion 1040B.

Next, the manufacturing process up to the construction of the connecting member 1036 will be described with reference to FIG. FIG. 5A shows a cross-sectional view when the fuel cell 1012 provided with the gas manifold 1004 is slidably inserted into the module container main body 1014. FIG. 5B shows a cross-sectional view when the first pipe 1006A and the second pipe 1006B are welded and joined to the connecting member main body 1038. FIG. 5C shows a cross-sectional view when the connecting member lid 1040 is welded to the connecting member main body 1038.

A reformer 1024 is fixed above the inside of the module container main body 1014 shown in FIG. 5 (A), and the reformer 1024 has a first pipe 1006A. In the module container main body 1014 having the reformer 1024 and the first pipe 1006A, a plurality of fuel cell cells 1012 having a gas manifold 1004 and a second pipe 1006B below are slidably slid from one side surface 1016 in which a plurality of fuel cell cells 1012 are opened. It is inserted (thick black arrow in FIG. 5 (A)). Here, the connecting member main body 1038 is inserted into the module container main body 1014 with the connecting member main body 1038 inserted into the second pipe 1006B.

After insertion, as shown in FIG. 5 (B), by sliding the connecting member main body 1038 upward (dotted line arrow in FIG. 5 (B)), the first pipe 1006A is inserted into the insertion hole 1038E of the connecting member main body 1038. And the second pipe 1006B can be inserted. As a result, when the connection member main body 1038 is attached to the first pipe 1006A and the second pipe 1006B, it is avoided from coming into contact with surrounding parts such as the fuel cell 1012, and the parts are attached while suppressing damage and deterioration. Is possible.

As shown in FIG. 5B, after the first pipe 1006A and the second pipe 1006B are inserted into the insertion holes 1038E of the connecting member main body 1038, they are welded and joined inside the connecting member main body 1038 ( (B) in FIG. 5 (B). Here, the inside of the connecting member main body 1038 and the fuel cell 1012 are shielded, and the welding droplets between the first pipe 1006A and the second pipe 1006B and the connecting member main body 1038 are completely blocked by the joining member. Therefore, contamination / deterioration of the fuel cell 1012 due to welding can be reliably suppressed.

Further, since the open surface 1038D of the connecting member main body 1038 is arranged on the one side surface 1016 side of the module container main body 1014, the welding work inside the connecting member main body 1038 performed from the outside of the one side surface 1016 becomes easy. That is, it is possible to improve the ease of welding work while suppressing the scattering of welding droplets on the fuel cell 1012.

As shown in FIG. 5C, the open surface 1038D is closed by the connecting lid 1040. Here, the end portion of the folded portion 1040B of the connecting portion lid 1040 and the end portion of the open surface 1038D are welded and joined on one side surface 1016 side (black coating in FIG. 5C). Since the welding joint between the connecting portion main body 1038 and the connecting portion lid 1040 is performed on the opposite side of the connecting member 1036, the connecting member 1036 can prevent the welding droplets from adhering to the fuel cell 1012. That is, it is possible to form the connecting member 1036 while suppressing contamination / deterioration of the fuel cell 1012 due to welding droplets.

Further, as shown in FIG. 5C, the connecting member 1036 is located at the height of the combustion unit 1030. As a result, since the connecting member 1036 and the combustion chamber 1030 are in close proximity to each other, the fuel gas flowing inside can receive heat directly from the combustion chamber 1030, and the fuel gas can be effectively heated. Further, since it is arranged at a position separated from the fuel cell 1012, it is possible to suppress the risk that the welding droplets generated in the joining member 1036 are scattered on the fuel cell.

Next, the solid oxide fuel cell apparatus according to the embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 6 is an overall configuration diagram showing a solid oxide fuel cell device (SOFC) according to an embodiment of the present invention. As shown in FIG. 6, the solid oxide fuel cell device (SOFC) 1 according to the embodiment of the present invention includes a fuel cell module 2 and an auxiliary machine unit 4.

The fuel cell module 2 includes a housing 6, and a metal module container 8 is built in the housing 6 via a heat insulating material 7. In the power generation chamber 10 which is a lower part of the module container 8 which is a closed space, a fuel cell which performs a power generation reaction with a fuel gas and an oxidant gas (hereinafter, appropriately referred to as “power generation air” or “air”) The cell assembly 12 is housed. The fuel cell assembly 12 is configured by connecting a plurality of fuel cell units 16 in series.

A combustion chamber 18 as a combustion unit is formed above the power generation chamber 10 of the module container 8 of the fuel cell module 2, and the residue not used in the power generation reaction (does not contribute to power generation) in this combustion chamber 18. The fuel gas and the remaining air burn to generate exhaust gas (in other words, combustion gas). Further, the module container 8 is covered with the heat insulating material 7 to suppress the heat inside the fuel cell module 2 from being dissipated to the outside air. A reformer 120 that reforms the fuel gas is arranged above the combustion chamber 18, and the reformer 120 is heated to a temperature at which the reforming reaction is possible by the combustion heat of the residual gas. There is.

Further, an evaporator 140 is provided in the heat insulating material 7 above the module container 8 in the housing 6. The evaporator 140 evaporates water to generate water vapor by exchanging heat between the supplied water and the exhaust gas, and a mixed gas of the water vapor and the raw fuel gas (hereinafter, "fuel gas"). (Sometimes referred to as) is supplied to the reformer 120 in the module container 8.

Next, the auxiliary machine unit 4 has a pure water tank 26 that stores water containing water contained in the exhaust from the fuel cell module 2 and turns it into pure water by a filter, and water supplied from the water storage tank. A water flow rate adjusting unit 28 (such as a "water pump" driven by a motor) for adjusting the flow rate of the water flow rate is provided. Further, the auxiliary machine unit 4 includes a gas shutoff valve 32 that shuts off the fuel supplied from the fuel supply source 30, which is a decrease in the supply of the raw material gas such as city gas, and a desulfurizer 36 for removing sulfur from the fuel gas. , A fuel flow rate adjusting unit 38 (such as a "fuel pump" driven by a motor) that adjusts the flow rate of fuel gas, and a valve 39 that shuts off the fuel gas flowing out of the fuel flow rate adjusting unit 38 in the event of power loss. There is. Further, the auxiliary machine unit 4 includes an electromagnetic valve 42 that shuts off the air supplied from the air supply source 40, a reforming air flow rate adjusting unit 44 that adjusts the air flow rate, and a power generation air flow rate adjusting unit 45 (with a motor). The driven "air blower" etc.), the first heater 46 that heats the reforming air supplied to the reformer 120, and the second heater 48 that heats the power generation air supplied to the power generation chamber. I have. These first heater 46 and second heater 48 are provided in order to efficiently raise the temperature at the time of start-up, but may be omitted. The desulfurization device 36 in this embodiment is a hydrogenated desulfurization device that supplies hydrogen to cause a desulfurization reaction.

In this embodiment, the partial oxidation reforming reaction (POX) and the steam reforming reaction (SR) are carried out from the POX step in which only the partial oxidation reforming reaction (POX) occurs in the reformer 120 when the apparatus is started. It may be configured so that the SR step in which only the steam reforming reaction occurs is performed through the ATR step in which the mixed auto-thermal reforming reaction (ATR) occurs, or the POX step is omitted and the ATR process is changed to the SR process. It may be configured so as to be migrated, or it may be configured so that only the SR step is performed by omitting the POX step and the ATR step. In the configuration in which only the SR process is performed, the reforming air flow rate adjusting unit 44 is unnecessary.

Next, the hot water production device 50 to which the exhaust gas is supplied is connected to the fuel cell module 2. Tap water is supplied to the hot water production apparatus 50 from the water supply source 24, and the tap water becomes hot water by the heat of the exhaust gas and is supplied to a hot water storage tank of an external water heater (not shown). Further, the fuel cell module 2 is provided with a control box 52 for controlling the supply amount of fuel gas and the like. Further, the fuel cell module 2 is connected to an inverter 54 which is a power extraction unit (power conversion unit) for supplying the electric power generated by the fuel cell module to the outside.

Next, the structure of the fuel cell module of the solid oxide fuel cell device according to the embodiment of the present invention will be described with reference to FIGS. 7 to 9. FIG. 7 is a side sectional view showing a fuel cell module of the solid oxide fuel cell apparatus according to an embodiment of the present invention, and FIG. 8 is a sectional view taken along the line III-III of FIG. 9 is an exploded perspective view of the module container and the air passage cover.

As shown in FIGS. 7 and 8, the fuel cell module 2 has a fuel cell assembly 12 and a reformer 120 provided inside a module container 8 covered with a heat insulating material 7, and also has a module container 8. It has an evaporator 140 provided outside and inside the heat insulating material 7.

First, as shown in FIG. 9, the module container 8 is composed of a substantially rectangular top plate 8a, a bottom plate 8c, and a pair of opposite side plates 8b connecting the sides extending in the longitudinal direction (horizontal direction in FIG. 7). A closing side plate that closes the tubular body and the two opposing openings at both ends of the tubular body in the longitudinal direction, and connects the sides extending in the width direction (horizontal direction in FIG. 8) of the top plate 8a and the bottom plate 8c. It consists of 8d and 8e.

In the module container 8, the top plate 8a and the side plate 8b are covered with the air passage cover 160. The air passage cover 160 has a top plate 160a and a pair of side plates 160b facing each other. An opening 167 for penetrating the exhaust pipe 171 and an opening 160c for connecting the power generation air introduction pipe 74 are provided in a substantially central portion of the top plate 160a. The top plate 160a and the top plate 8a, and the side plate 160b and the side plate 8b are separated by a predetermined distance. As a result, between the outside of the module container 8 and the heat insulating material 7, specifically, between the top plate 8a and the side plate 8b of the module container 8 and the top plate 160a and the side plate 160b of the air passage cover 160. Air passages 161a and 161b as oxidant gas supply passages are formed along the outer surfaces of the plate 160a and the side plates 160b (see FIG. 8).

At the lower part of the side plate 8b of the module container 8, a plurality of through holes 8f are provided (see FIG. 9). The power generation air is supplied into the air passage 161a from the power generation air introduction pipe 74 provided in the substantially central portion of the top plate 160a of the air passage cover 160 on the closed side plate 8e side of the module container 8 (FIG. 7). reference). Then, the air for power generation is injected into the power generation chamber 10 from the outlet 8f toward the fuel cell assembly 12 through the air passages 161a and 161b (see FIGS. 8 and 9).

FIG. 10 is a perspective view showing an inner surface of the closed side plate 8d constituting the module container 8. As shown in the figure, a first protrusion 180A and a second protrusion 180B extending in the vertical direction along the edges on both sides in the width direction are formed on the inner surface of the closing side plate 8d. The first protrusion 180A and the second protrusion 180B each have a rectangular horizontal cross-sectional shape. The inner side surfaces of the first protrusion 180A and the second protrusion 180B form a protrusion that projects toward the fuel cell. A groove 180C having a rectangular cross section is formed between the first protrusion 180A and the second protrusion 180B.

Further, inside the air passages 161a and 161b, as a heat exchange promoting member for promoting heat exchange between the exhaust gas in the first and second exhaust passages 172a and 172b and the air in the air passages 161a and 161b. Plate fins 162 and 163 are provided (see FIG. 8). The plate fins 162 are provided in the horizontal direction so as to extend in the longitudinal direction and the width direction between the top plate 8a of the module container 8 and the top plate 160a of the air passage cover 160. That is, the plate fins 162 are provided in the portion of the air passage 161a corresponding to the first exhaust passage 172a described later. Further, the plate fin 163 extends in the longitudinal direction and the vertical direction between the side plate 8b of the module container 8 and the side plate 160b of the air passage cover 160 and above the fuel cell unit 16. It is provided. That is, the plate fins 163 are provided in the portion of the air passage 161b corresponding to the second exhaust passage 172b and the exhaust concentration portion 176, which will be described later.

The power generation air flowing through the air passages 161a and 161b is inside the module container 8 inside the plate fins 162 and 163 (specifically, along the top plate 8a and the side plates 8b) when passing through the plate fins 162 and 163. It will be heated by exchanging heat with the exhaust gas passing through the provided exhaust passage). For this reason, the portions of the air passages 161a and 161b provided with the plate fins 162 and 163 function as heat exchangers (heat exchange portions). The portion provided with the plate fins 162 constitutes the main heat exchanger portion, and the portion provided with the plate fins 163 constitutes the subordinate heat exchanger portion.

Next, the evaporator 140 is fixed so as to extend in the horizontal direction on the top plate 8a of the module container 8. Further, a part 7a of the heat insulating material 7 is arranged between the evaporator 140 and the module container 8 so as to fill these gaps (see FIGS. 7 and 8).

Specifically, the evaporator 140 has a fuel supply pipe 63 that supplies water and raw fuel gas (may include reforming air) to one side end side in the longitudinal direction (left-right direction in FIG. 7). , An exhaust gas discharge pipe 82 (see FIG. 8) for discharging exhaust gas is connected, and an upper end portion of the exhaust pipe 171 is connected to the other end side in the longitudinal direction. The exhaust pipe 171 penetrates the opening 167 formed in the top plate 160a of the air passage cover 160 and extends downward, and is connected to the exhaust port 111 formed on the top plate 8a of the module container 8. The exhaust port 111 is an opening for discharging the exhaust gas generated in the combustion chamber 18 in the module container 8 to the outside of the module container 8, and is located at substantially the center of the top plate 8a having a substantially rectangular top view of the module container 8. It is formed.

Further, as shown in FIGS. 7 and 8, the evaporator 140 has a substantially rectangular evaporator case 141 when viewed from above. The evaporator case 141 is formed by joining two low-height bottomed rectangular tubular upper cases 142 and lower cases 143 with an intermediate plate 144 sandwiched between them.

Therefore, the evaporator case 141 has a two-layer structure in the vertical direction, and an exhaust passage portion 140A through which the exhaust gas supplied from the exhaust pipe 171 passes is formed in the lower layer portion, and fuel is formed in the upper layer portion. An evaporation unit 140B that evaporates the water supplied from the supply pipe 63 to generate water vapor and a mixing unit 140C that mixes the water vapor generated by the evaporation unit 140B and the raw fuel gas supplied from the fuel supply pipe 63 are provided. Has been done.

The evaporation section 140B and the mixing section 140C are formed in a space in which the evaporator 140 is partitioned by a partition plate provided with a plurality of communication holes (slits). Further, the evaporation portion 140B is filled with alumina balls (not shown).

Further, the exhaust passage portion 140A is similarly partitioned into three spaces from the upstream side to the downstream side of the exhaust gas by two partition plates having a plurality of communication holes. Then, the second space is filled with a combustion catalyst (not shown). That is, the evaporator 140 of this embodiment includes a combustion catalyst.

In such an evaporator 140, heat exchange is performed between the water in the evaporation section 140B and the exhaust gas passing through the exhaust passage section 140A, and the water in the evaporation section 140B evaporates due to the heat of the exhaust gas. Water vapor will be generated. Further, heat exchange is performed between the mixed gas in the mixing section 140C and the exhaust gas passing through the exhaust passage section 140A, and the temperature of the mixed gas is raised by the heat of the exhaust gas.

Further, as shown in FIG. 7, a mixed gas supply pipe 112 for supplying the mixed gas to the reformer 120 is connected to the mixing unit 140C. The mixed gas supply pipe 112 is arranged so as to pass through the inside of the exhaust pipe 171 and has one end connected to the opening 144a formed in the intermediate plate 144 and the other end formed on the top surface of the reformer 120. It is connected to the mixed gas supply port 120a. The mixed gas supply pipe 112 passes through the exhaust passage portion 140A and the exhaust pipe 171 and extends vertically downward to the inside of the module container 8, where it is bent by approximately 90 ° and extends horizontally along the top plate 8a. , It is bent downward by approximately 90 ° and connected to the reformer 120.

Next, the reformer 120 is arranged above the combustion chamber 18 so as to extend horizontally along the longitudinal direction of the module container 8, and the exhaust gas guiding member 130 is placed between the reformer 120 and the top plate 8a of the module container 8. It is fixed to the top plate 8a in a state of being separated by a predetermined distance. The reformer 120 has a substantially rectangular outer shape when viewed from above, but is an annular structure in which a through hole 120b is formed in a central portion, and has a housing in which an upper case 121 and a lower case 122 are joined. ing. The through hole 120b is located so as to overlap the exhaust port 111 formed in the top plate 8a in a top view, and preferably the exhaust port 111 is formed at the center position of the through hole 120b.

On one end side (closed side plate 8e side of the module container 8) of the reformer 120 in the longitudinal direction, the mixed gas supply pipe 112 is connected to the mixed gas supply port 120a provided in the upper case 121, and the other end side (the other end side (closed side plate 8e side). On the closed side plate 8d side), the fuel gas supply pipe 64 is connected to the lower case 122. Therefore, the reformer 120 receives the mixed gas (that is, the raw fuel gas mixed with water vapor (which may include reforming air)) from the mixed gas supply pipe 112, reforms the mixed gas internally, and reforms the mixed gas. It is configured to discharge the reformed gas (that is, the fuel gas) from the fuel gas supply pipe 64.

The reformer 120 has a mixed gas receiving unit 120A that receives the mixed gas from the mixed gas supply pipe 112 into the reformer 120 by partitioning the internal space into three spaces by two partition plates 123a and 123b. A reforming unit 120B filled with a reforming catalyst (not shown) for reforming the mixed gas, and a gas discharge unit 120C for discharging the gas that has passed through the reforming unit 120B are formed. (See FIG. 7). The reforming section 120B is a space sandwiched between the partition plates 123a and 123b, and the reforming catalyst is held in this space. The mixed gas and the reformed fuel gas can move through a plurality of communication holes (slits) provided in the partition plates 123a and 123b. Further, as the reforming catalyst, a catalyst in which nickel is added to the surface of an alumina sphere or a catalyst in which ruthenium is added to the surface of an alumina sphere is appropriately used.

The mixed gas supplied from the evaporator 140 via the mixed gas supply pipe 112 is ejected to the mixed gas receiving unit 120A through the mixed gas supply port 120a. This mixed gas is expanded in the mixed gas receiving section 120A to reduce the ejection speed, passes through the partition plate 123a, and is supplied to the reforming section 120B.

In the reforming section 120B, the mixed gas moving at a low speed is reformed into a fuel gas by the reforming catalyst, and this fuel gas passes through the partition plate 123b and is supplied to the gas discharging section 120C.

The fuel gas supply pipe 64 as the fuel gas supply passage extends downward along the closing side plate 8d in the module container 8, is bent by approximately 90 ° near the bottom plate 8c, and extends in the horizontal direction, and the fuel cell assembly 12 It enters the gas gas manifold 66 formed below the above, and further extends in the gas gas manifold 66 in the horizontal direction to the vicinity of the closing side plate 8e on the opposite side. The fuel gas supply pipe 64 is divided into a first pipe 64A connected to the reformer 120 and a second pipe 64B connected to the gas gas manifold 66, and these first pipe 64A and the second pipe 64B are divided. The second pipe 64B is configured so that the inside of the pipe communicates with the connecting member 190. The connecting member 190 is provided at substantially the height of the combustion portion, and is located diagonally above the fuel cell assembly 12.

Further, as shown in FIG. 7, a hydrogenation desulfurizer pipe 65 is attached to the connecting member 190. With this configuration, fuel gas can be supplied from the connecting member 190 to the hydrogenated desulfurizer pipe 65.

A plurality of fuel supply holes 64b are formed on the lower surface of the horizontal portion 64a of the fuel gas supply pipe 64, and fuel gas is supplied into the gas gas manifold 66 from the fuel supply holes 64b. A lower support plate 68 having a through hole for supporting the fuel cell unit 16 is attached above the gas gas manifold 66, and the fuel gas in the gas gas manifold 66 is introduced into the fuel cell unit 16. Will be supplied. Further, an ignition device 83 for starting combustion of fuel gas and air is provided in the combustion chamber 18.

The entire circumference of the first pipe 64A and the second pipe 64B is surrounded by the connecting member 190. FIG. 11 is a vertically enlarged cross-sectional view of the fuel supply pipe 64 with the connecting member 190 attached.

FIG. 11 is a perspective view showing the periphery of the connecting member 190 in the assembled state. The closing side plate 8d is closed after the connecting member 190 is attached to the fuel gas supply pipe 64. Then, in the state where the closing side plate 8d is closed, the connecting member 190 is housed in the groove 180C of the closing side plate 8d. The surface of the connecting member 190 on the fuel cell unit 16 side is located on the same plane as the protruding surface of the closing side plate 8d on the fuel cell unit 16 side of the first protrusion 180A and the second protrusion 180B. .. As a result, it is possible to suppress the outflow of the power generation air in the power generation chamber 10 to the groove 180C, and to prevent the airflow in the power generation chamber 10 and the combustion chamber 18 from being disturbed.

The fuel gas supply pipe 64 as the fuel gas supply passage extends downward along the closing side plate 8d in the module container 8, is bent by approximately 90 ° near the bottom plate 8c, and extends in the horizontal direction, and the fuel cell assembly 12 It enters the gas gas manifold 66 formed below the above, and further extends in the gas gas manifold 66 in the horizontal direction to the vicinity of the closing side plate 8e on the opposite side. A plurality of fuel supply holes 64b are formed on the lower surface of the horizontal portion 64a of the fuel gas supply pipe 64, and fuel gas is supplied into the gas gas manifold 66 from the fuel supply holes 64b. A lower support plate 68 having a through hole for supporting the fuel cell unit 16 is attached above the gas gas manifold 66, and the fuel gas in the gas gas manifold 66 is introduced into the fuel cell unit 16. Will be supplied. Further, an ignition device 83 for starting combustion of fuel gas and air is provided in the combustion chamber 18.

The exhaust gas guiding member 130 is arranged between the reformer 120 and the top plate 8a so as to extend horizontally along the longitudinal direction of the module container 8. The exhaust gas guiding member 130 includes a lower guiding plate 131 and an upper guiding plate 132 separated by a predetermined distance in the vertical direction, and connecting plates 133 and 134 to which both ends in the longitudinal direction are attached (FIG. 7). , See Fig. 8). Both ends of the upper guide plate 132 in the width direction are bent downward and connected to the lower guide plate 131. The upper end of the connecting plates 133 and 134 is connected to the top plate 8a, and the lower end is connected to the reformer 120, whereby the exhaust gas guiding member 130 and the reformer 120 are fixed to the top plate 8a. ing.

The lower guide plate 131 is formed with a convex stepped portion 131a in which the central portion in the width direction (left-right direction in FIG. 8) projects downward. On the other hand, in the upper guide plate 132, like the lower guide plate 131, the concave portion 132a is formed so that the central portion in the width direction is concave downward. The convex step portion 131a and the concave portion 132a extend in the longitudinal direction in parallel in the vertical direction. The mixed gas supply pipe 112 extends horizontally in the recess 132a in the module container 8, then bends downward near the closing side plate 8e, penetrates the upper guide plate 132 and the lower guide plate 131, and penetrates the upper guide plate 132 and the lower guide plate 131. It is connected to the reformer 120.

In the exhaust gas guiding member 130, the gas reservoir (gas heat insulating layer) 135, which is an internal space that functions as a heat insulating layer, is formed by the upper guiding plate 132, the lower guiding plate 131, and the connecting plates 133, 134. The gas reservoir 135 communicates with the combustion chamber 18 in fluid communication. That is, the upper guide plate 132, the lower guide plate 131, and the connecting plates 133 and 134 are connected so as to form a predetermined gap, and are not airtightly connected. Exhaust gas can flow into the gas reservoir 135 from the combustion chamber 18 during operation, and air can flow in from the outside when the gas reservoir 135 is stopped. However, as a whole, gas moves between the inside and outside of the gas reservoir 135. Is gradual.

The upper guide plate 132 is arranged with a predetermined vertical distance from the top plate 8a, and the upper surface of the upper guide plate 132 and the top plate 8a are arranged horizontally along the longitudinal direction and the width direction. An extending first exhaust passage 172a is formed. The first exhaust passage 172a is juxtaposed with the air passage 161a with the top plate 8a of the module container 8 interposed therebetween, and the plate fins 162, 163 in the air passages 161a and 161b are contained in the first exhaust passage 172a. Similar plate fins 175a are arranged. The plate fins 175a are provided at substantially the same position as the plate fins 162 in the top view, and face each other in the vertical direction with the top plate 8a interposed therebetween.

The upper guide plate 132 is arranged at a predetermined horizontal distance from the side surface of the upper guide plate 132 and the side plate 8b, and is arranged in the longitudinal direction and the vertical direction between the side surface of the upper guide plate 132 and the side plate 8b. An extending second exhaust passage 172b is formed. The second exhaust passage 172b communicates with the first exhaust passage 172a at the upper part. Plate fins 175b similar to the plate fins 162 and 163 in the air passages 161a and 161b are also arranged in the second exhaust passage 172b. The lower end of the plate fin 175b extends to the height of the lower guide plate 131.

Of the air passages 161a and 161b and the first and second exhaust passages 172a and 172b, in the portion where the plate fins 162, 163, 175a and 175b are provided, the power generation air flowing through the air passages 161a and 161b and the first and first Efficient heat exchange is performed with the exhaust gas flowing through the second exhaust passages 172a and 172b, and the heat of the exhaust gas raises the temperature of the power generation air.

Further, the reformer 120 is arranged at a predetermined horizontal distance from the side plate 8b of the module container 8, and exhaust gas is passed between the reformer 120 and the side plate 8b from the lower side to the upper side. A third exhaust passage 173 is formed.

Further, the lower guide plate 131 is arranged at a predetermined vertical distance from the top surface of the upper case 121 of the reformer 120, and is located between the lower guide plate 131 and the upper case 121 and the reformer. The through hole 120b of 120 forms a fourth exhaust passage 174 through which the exhaust gas that has passed through the through hole 120b from below to above passes. The fourth exhaust passage 174 merges with the third exhaust passage 173 above the reformer 120 and in the vicinity of the side plate 8b, and an exhaust concentration portion 176 in which the exhaust gas concentrates is formed.

Next, the fuel cell unit 16 will be described with reference to FIG. FIG. 12 is a partial cross-sectional view showing a fuel cell unit of a solid oxide fuel cell device according to an embodiment of the present invention.
As shown in FIG. 12, the fuel cell unit 16 includes a fuel cell 84 and inner electrode terminals 86 which are caps connected to both ends of the fuel cell 84.

The fuel cell 84 is a tubular structure extending in the vertical direction, and has a cylindrical inner electrode layer 90 forming a fuel gas flow path 88 inside, a cylindrical outer electrode layer 92, an inner electrode layer 90, and an outer side. It includes an electrolyte layer 94 between the electrode layer 92 and the electrode layer 92. The inner electrode layer 90 is a fuel electrode through which the fuel gas passes and has a (−) pole, while the outer electrode layer 92 is an air electrode in contact with air and has a (+) pole.

Since the inner electrode terminals 86 attached to the upper end side and the lower end side of the fuel cell 84 have the same structure, the inner electrode terminals 86 attached to the upper end side will be specifically described here. The upper 90a of the inner electrode layer 90 includes an outer peripheral surface 90b and an upper end surface 90c exposed to the electrolyte layer 94 and the outer electrode layer 92. The inner electrode terminal 86 is connected to the outer peripheral surface 90b of the inner electrode layer 90 via a conductive sealing material 96, and further comes into direct contact with the upper end surface 90c of the inner electrode layer 90 to contact the inner electrode layer 90. It is electrically connected. A fuel gas flow path thin tube 98 communicating with the fuel gas flow path 88 of the inner electrode layer 90 is formed in the central portion of the inner electrode terminal 86.

The fuel gas flow path thin tube 98 is an elongated thin tube provided so as to extend in the axial direction of the fuel cell 84 from the center of the inner electrode terminal 86. Therefore, a predetermined pressure loss is generated in the flow of fuel gas flowing from the gas gas manifold 66 (see FIG. 7) into the fuel gas flow path 88 through the fuel gas flow path thin tube 98 of the lower inner electrode terminal 86. Occur. Therefore, the fuel gas flow path thin tube 98 of the lower inner electrode terminal 86 acts as an inflow side flow path resistance portion, and the flow path resistance is set to a predetermined value. Further, a predetermined pressure loss also occurs in the flow of the fuel gas flowing out from the fuel gas flow path 88 through the fuel gas flow path thin tube 98 of the upper inner electrode terminal 86 to the combustion chamber 18 (see FIG. 7). Therefore, the fuel gas flow path thin tube 98 of the upper inner electrode terminal 86 acts as an outflow side flow path resistance portion, and the flow path resistance is set to a predetermined value.

The inner electrode layer 90 is composed of, for example, a mixture of Ni and zirconia doped with at least one selected from rare earth elements such as Ca, Y, and Sc, and Ni and ceria doped with at least one selected from rare earth elements. It is formed from at least one of a mixture, a mixture of Ni and a lantern garade doped with at least one selected from Sr, Mg, Co, Fe and Cu.

The electrolyte layer 94 is composed of, for example, zirconia doped with at least one selected from rare earth elements such as Y and Sc, ceria doped with at least one selected from rare earth elements, and lanthanum gallate doped with at least one selected from Sr and Mg. Formed from at least one of.

The outer electrode layer 92 is, for example, a lanthanum manganate doped with at least one selected from Sr and Ca, and a lanthanum ferrite doped with at least one selected from Sr, Co, Ni and Cu, Sr, Fe, Ni and Cu. It is formed from at least one of lantern cobaltite, silver, etc. doped with at least one selected from.

In the fuel cell assembly 12, the inner electrode terminal 86 attached to the inner electrode layer 90 which is the fuel electrode of each fuel cell unit 16 is the outer electrode layer 92 which is the air electrode of another fuel cell unit 16. By being electrically connected to the outer peripheral surface, all 128 fuel cell units 16 are connected in series.

Next, with reference to FIGS. 13 and 14, the flow of gas in the fuel cell module of the solid oxide fuel cell apparatus according to the embodiment of the present invention will be described. FIG. 13 is a side sectional view showing a fuel cell module of a solid oxide fuel cell apparatus according to an embodiment of the present invention, which is the same as that of FIG. 7, and FIG. 14 is a side sectional view of FIG. -It is a cross-sectional view along line III. 13 and 14, respectively, are views in which arrows indicating the gas flow are newly added to FIGS. 7 and 8, respectively, and are shown in a state where the heat insulating material 7 is removed for convenience of explanation. In the figure, the solid line arrow indicates the fuel gas flow, the broken line arrow indicates the power generation air flow, and the alternate long and short dash line arrow indicates the exhaust gas flow.

As shown in FIG. 13, water and raw fuel gas (fuel gas) are placed in an evaporator 140B provided on the upper layer of the evaporator 140 from a fuel supply pipe 63 connected to one end side in the longitudinal direction of the evaporator 140. Will be supplied. The water supplied to the evaporation section 140B is heated by the exhaust gas flowing through the exhaust passage section 140A provided in the lower layer of the evaporator 140 to become steam. The steam and the raw fuel gas supplied from the fuel supply pipe 63 flow in the downstream direction in the evaporation section 140B and are mixed in the mixing section 140C. The mixed gas in the mixing portion 140C is heated by the exhaust gas flowing through the lower exhaust passage portion 140A.

The mixed gas (fuel gas) formed in the mixing unit 140C is supplied to the reformer 120 in the module container 8 through the mixed gas supply pipe 112. Since the mixed gas supply pipe 112 passes through the exhaust passage portion 140A, the exhaust pipe 171 and the first exhaust passage 172a in this order, the exhaust gas flowing through these passages further causes the mixed gas in the mixed gas supply pipe 112 to further increase. It is heated.

The mixed gas flows into the mixed gas receiving section 120A in the reformer 120, passes through the partition plate 123a from here, and flows into the reforming section 120B. The mixed gas is reformed in the reforming section 120B to become a fuel gas. The fuel gas thus generated passes through the partition plate 123b and flows into the gas discharge unit 120C.

Further, the fuel gas that has flowed into the fuel gas supply pipe 64 (first pipe 64A) from the gas discharge unit 120C is supplied into the connecting member 190. Inside the connecting member 190, the fuel gas supply pipe 64 (second pipe 64B) and the hydrogenated desulfurizer pipe 65 are branched. The fuel gas flowing out from the connecting member 190 to the fuel gas supply pipe 64 (second pipe 64B) is supplied into the gas gas manifold 66 from the fuel supply hole 64b provided in the horizontal portion 64a, and is supplied from the gas gas manifold 66 to each fuel cell. It is supplied into the unit 16.

Further, as shown in FIGS. 13 and 14, the air for power generation is supplied from the air introduction pipe 74 for power generation to the air passage 161a. When the air for power generation passes through the plate fins 162 and 163 in the air passages 161a and 161b, the first and second exhaust passages 172 and 2 formed in the module container 8 below the plate fins 162 and 163 are formed. Efficient heat exchange with the exhaust gas passing through 173 will result in heating.

After that, the power generation air is injected into the power generation chamber 10 from the plurality of outlets 8f provided in the lower part of the side plate 8b of the module container 8 toward the fuel cell assembly 12. In this embodiment, since the exhaust passage is not formed in the lateral portion of the fuel cell assembly 12, heat exchange between the power generation air and the exhaust gas is suppressed in this portion. Therefore, in the lateral portion of the fuel cell assembly 12, the temperature unevenness in the vertical direction is less likely to occur in the power generation air in the air passage 161b.

Further, as shown in FIG. 14, the fuel gas not used for power generation in the power generation chamber 10 is burned in the combustion chamber 18 to become exhaust gas (combustion gas), and rises in the module container 8. Specifically, the exhaust gas branches into the third exhaust passage 173 and the fourth exhaust passage 174, and is between the outer surface of the reformer 120 and the side plate 8b of the module container 8 and the reformer 120. It passes between the reformer 120 and the exhaust gas guiding member 130 through the through hole 120b of the above. At this time, the exhaust gas passing through the fourth exhaust passage 174 is divided in the width direction by the convex step portion 131a arranged above the through hole 120b of the reformer 120, and stays at the lower part of the exhaust gas guiding member 130. It is guided toward the third exhaust passage 173 without any reason, and joins the exhaust gas flowing through the third exhaust passage 173 at the exhaust concentration portion 176. Here, since the plate fins 175b are provided in the second exhaust passage 172, the exhaust gas that has passed through the third exhaust passage 173 and the fourth exhaust passage 174 stays in the exhaust concentration portion 176 (A in FIG. 14). Part).

After that, the exhaust gas is introduced from the exhaust concentration unit 176 into the second exhaust passage 172b. Then, the exhaust gas that has passed through the second exhaust passage 172b flows horizontally through the first exhaust passage 172a and flows out from the exhaust port 111 formed in the center of the top plate 8a of the module container 8.

When the exhaust gas stays in the exhaust concentrated portion 176, heat is generated between the power generation air and the exhaust gas via the plate fins 163 provided in the portion corresponding to the exhaust concentrated portion 176 in the air passage 161b. The exchange will take place. Further, when the exhaust gas flows through the second exhaust passage 172b and the first exhaust passage 172a, the plate fins 175b and 175a provided in the second and first exhaust passages 172b and 172a and the air passages 161a and 161b Efficient heat exchange is performed between the power generation air and the exhaust gas via the plate fins 162 and 163 provided in the portions corresponding to the plate fins 175b and 175a inside. In this way, the heat of the exhaust gas raises the temperature of the power generation air.

Then, the exhaust gas flowing out from the exhaust port 111 passes through the exhaust pipe 171 provided outside the module container 8 and flows into the exhaust passage portion 140A of the evaporator 140, passes through the exhaust passage portion 140A, and then evaporates. It is discharged from the vessel 140 to the exhaust gas discharge pipe 82. When the exhaust gas flows through the exhaust passage portion 140A of the evaporator 140, it exchanges heat with the mixed gas in the mixing portion 140C of the evaporator 140 and the water in the evaporator 140B as described above.

1 Solid oxide fuel cell device 2 Fuel cell module 4 Auxiliary unit 6 Housing 7 Insulation material 8 Module container 8a Top plate 8b Side plate 8c Bottom plate 8d Closed side plate 8e Closed side plate 8f Outlet 10 Power generation chamber 12 Fuel cell assembly 16 Fuel cell cell unit 18 Combustion chamber 24 Water supply source 26 Pure water tank 28 Water flow rate adjustment unit 30 Fuel supply source 32 Gas shutoff valve 36 Desulfurizer (hydrogenated desulfurizer)
38 Fuel flow adjustment unit 39 Valve 40 Air supply source 42 Electromagnetic valve 44 Reform air flow adjustment unit 45 Power generation air flow adjustment unit 46 1st heater 48 2nd heater 50 Hot water production device 52 Control box 54 Inverter 63 Fuel supply piping 64 Fuel gas supply pipe 64a Horizontal part 64b Fuel supply hole 65 Hydrophobic desulfurization pipe 66 Gas manifold 68 Lower support plate 74 Power generation air introduction pipe 82 Exhaust gas discharge pipe 83 Ignition device 84 Fuel cell cell 86 Inner electrode terminal 88 Fuel gas Flow path 90 Inner electrode layer 92 Outer electrode layer 94 Electrolyte layer 96 Sealing material 98 Fuel gas flow path Thin tube 111 Exhaust port 112 Mixed gas supply pipe 120 Reformer 120A Mixed gas receiving part 120B Reforming part 120C Gas discharging part 120a Mixed gas Supply port 120b Through hole 121 Upper case 122 Lower case 123a Partition plate 123b Partition plate 130 Exhaust gas guiding member 131 Lower guiding plate 131a Convex stepped portion 132 Upper guiding plate 132a Recessed portion 133 Connecting plate 134 Connecting plate 135 Gas heat insulating layer (gas) Tame)
140 Evaporator 140A Exhaust passage 140B Evaporation 140C Mixing 141 Evaporator case 142 Upper case 143 Lower case 144 Intermediate plate 144a Opening 160 Air passage cover 160a Top plate 160b Side plate 161a Air passage 161b Air passage 162 Plate fin 163 Plate fin 164 Flow path direction adjustment part 167 Opening 171 Exhaust pipe 172a First exhaust passage 172b Second exhaust passage 173 Third exhaust passage 174 Fourth exhaust passage 175a Plate fin 175b Plate fin 176 Exhaust concentration part 180A First protrusion 180B First 2 protrusion 180C groove 190 connection member 1002 fuel cell module 1004 gas manifold 1006 fuel gas supply pipe 1006A first pipe 1006B second pipe 1010 lower support plate 1012 fuel cell 1014 module container body 1016 one side surface 1018 module container 1020 Closed side plate (module container lid)
1022 Air passage cover 1024 Reformer 1026 Air outlet 1028 Power generation air introduction pipe 1030 Combustion chamber 1032 Exhaust passage 1034 Air passage 1036 Connection member 1038 Connection member body 1038A Upper surface 1038B Lower surface 1038C Side surface 1038D Open surface 1038E Insert hole 1040 Connection member Lid 1040A Main body 1040B Folded part

Claims (8)

It is a solid oxide fuel cell device equipped with a plurality of fuel cell cells that generate electricity by a power generation reaction between a fuel gas and an oxidant gas.
A rectangular parallelepiped module container containing the plurality of fuel cell cells and having at least one side open.
The module container lid that covers one side surface and
A reformer fixed to the module container and arranged above the inside of the module container,
A gas manifold provided below the inside of the module container and supplying the fuel gas generated by the reformer to the plurality of fuel cell cells erected on the upper surface.
A first pipe arranged on the one side surface side and allowing fuel gas to flow out from the connected reformer, and
A second pipe arranged on the one side surface side to allow fuel gas to flow into the connected gas manifold, and
A connecting member into which the first pipe and the end of the second pipe are inserted to communicate the first pipe and the second pipe.
With
The connecting member comprises a connecting member main body that shields the inside of the connecting member and the plurality of fuel cell cells, and a connecting member lid.
A solid oxide fuel cell device, wherein the first pipe and the second pipe are welded and joined to the connecting member main body inside the connecting member. The connecting member main body is formed in a rectangular parallelepiped shape, the connecting member main body has an open surface on different sides to the side where the plurality of fuel cells are arranged, the open surface is covered with the connecting member cover body The solid oxide fuel cell device according to claim 1, wherein the fuel cell device is characterized by the above. The fuel cell device according to claim 2, wherein the connecting member main body has the open surface on one side surface side. The connecting member lid is provided inside the open surface of the connecting member main body, and the connecting member lid is provided on the main surface for closing the open surface and on the outer shell of the main surface outside the connecting member main body. The solid oxide according to claim 3, which has a folded-back portion protruding to one side surface side, and the end portion on the open surface and the end portion on the folded-back portion are welded and joined. Type fuel cell device. The solid oxide fuel cell according to claim 4, wherein the flow path cross-sectional area of the connecting member is larger than the flow path cross-sectional area of the first pipe and / or the second pipe. apparatus. The solid oxide fuel cell device according to claim 5, wherein a combustion chamber is formed above the plurality of fuel cell cells, and the connecting member is located at the height of the combustion chamber. The connection member main body is formed with an insertion hole, and the end portion of the first pipe and / or the second pipe is located inside the insertion hole, according to claims 1 to 6. The solid oxide fuel cell apparatus according to any one of the following items. The pipe for the hydrogenated desulfurizer, which is provided with a hydrogenated desulfurizer to which a part of the fuel gas generated by the reformer is supplied and supplies the fuel gas to the hydrogenated desulfurizer , is the connecting member main body or the connection. The solid oxide fuel cell apparatus according to any one of claims 1 to 7, wherein the solid oxide fuel cell apparatus is joined to a member lid.

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