JP2018156810A - Solid oxide fuel cell device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid oxide fuel cell device including a module container, where a reformer is fixed internally and multiple fuel battery cells are inserted from the side opening, and realizing improvement of manufacturability and further cost reduction, while restraining pollution and deterioration of the fuel battery cell during manufacture of a module.SOLUTION: A solid oxide fuel cell device includes a first pipeline for making fuel gas outflow from a connected reformer, a second pipeline for making fuel gas flow into a connected gas manifold, and a connection member into which the ends of the first and second pipelines are inserted, and the first and second pipelines are interconnected. The connection member consists of a connection member body for intercepting the interior of the connection member and multiple fuel battery cells, and a connection member lid. In the connection member, the first and second pipelines are joined to the connection member body by welding.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a fuel cell device. In particular, the present invention relates to a fuel cell device using a solid oxide fuel cell that generates power by a reaction between a fuel gas obtained by reforming a raw material gas and an oxidant gas.

  A solid oxide fuel cell device (hereinafter also referred to as “SOFC”) uses an oxide ion conductive solid electrolyte as an electrolyte, and a fuel cell having electrodes attached to both sides thereof in a multi-module container. The fuel gas is supplied to one electrode (fuel electrode) of the fuel battery cell, and the oxidant gas (hereinafter also referred to as air or power generation air) is supplied to the other electrode (air electrode). It is a device that extracts power generated by a power generation reaction. The fuel cell device operates at a relatively high temperature of, for example, about 700 to 1000 ° C. with respect to another fuel cell device such as a polymer electrolyte fuel cell device, and is generally more energy efficient than other fuel cell devices.

  In such a solid oxide fuel cell device, for example, as described in Patent Document 1, fuel gas and power generation air 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. The fuel gas reformed by the reformer is sent to a gas manifold provided below the fuel cell via a fuel gas supply pipe extending in the vertical direction on the side of the fuel cell. To be supplied to the fuel cell.

  Here, Patent Document 1 discloses a device in which a reformer is fixed to a top surface inside a module container. Further, in Patent Document 1, an opening for inserting a plurality of fuel cells is provided on one side surface of the module container, the plurality of fuel cells are slidably inserted into the module container from the opening, and the opening is a lid body. Is hermetically sealed. With such a configuration, the work procedure after the fuel cell is accommodated is reduced compared to the case where a plurality of module container lids are fixed by welding around the plurality of fuel cells. Will improve.

  In addition, when welding work is performed on the module container, welding droplets (metal such as spatter that scatters during bonding) adhere to the surface of the fuel cell, and in the portion where the welding droplets adhere, power generation of the fuel cell. Is impeded, and the power generation performance of the fuel cell is deteriorated. As described above, when a plurality of fuel cells are slidably inserted into the module container and the opening is closed by the lid, the welding procedure after the fuel cells are accommodated is reduced. In addition, the risk of contamination / deterioration of the fuel cell due to welding splashes can be suppressed.

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

JP 2013-257984 A JP 2011-18456 A

  However, a commercially available pipe joint is not assumed to be used in a high temperature environment, and has a lower heat resistance than a fuel gas supply pipe or the like. For this reason, if a pipe joint receives the heat of a combustion chamber, a pipe joint will deteriorate and the surface will peel in powder form. When such exfoliated powder adheres to the fuel cell, the fuel cell is contaminated. For this reason, when a pipe joint having high heat resistance is separately manufactured and used, the cost increases.

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

  Accordingly, the present invention relates to a solid oxide fuel cell device having a module container in which a reformer is fixed and a plurality of fuel cells are inserted from side openings. The present invention provides a solid oxide fuel cell device for improving the manufacturability and further reducing the cost while suppressing the contamination and deterioration of the fuel cell.

  One aspect of a fuel cell device according to the present invention is a solid oxide fuel cell device including a plurality of fuel cells that generate electric power by a power generation reaction between a fuel gas and an oxidant gas. A rectangular parallelepiped module container housed in at least one side surface, a module container lid body covering one side surface, a reformer fixed to the module container and disposed above the inside of the module container; A gas manifold that is provided below the inside of the module container and supplies fuel gas generated by the reformer to a plurality of fuel cells standing on the upper surface, and a reformer that is disposed and connected on one side surface A first pipe that allows fuel gas to flow out of the gas, a second pipe that is arranged on one side surface and that flows into the gas manifold to which the fuel gas is connected, and ends of the first pipe and the second pipe are inserted The A connection member that communicates the first pipe and the second pipe, and the connection member includes a connection member body that shields the inside of the connection member and the plurality of fuel cells, and a connection member lid. In the connection member, the first pipe and the second pipe are welded to the connection member main body.

  Conventionally, a reformer is fixed in the upper part of the module container and one side surface is opened. After inserting a plurality of fuel cells having a gas manifold in the lower part into the module container, the reformer is connected to the reformer. The first pipe and the second pipe connected to the gas manifold are joined by a pipe joint. Since the first pipe and the second pipe are provided so as to hang down the side of the assembly of the plurality of fuel cells, the surface of the pipe joint deteriorates due to the influence of the heat generated by the fuel cells. There was a possibility that it would be adversely affected by being powdered and scattered in the fuel cell.

  Here, since the first pipe and the second pipe are connected in the vicinity of the plurality of fuel cells, when welding them without using the pipe joint, the welding droplets adhere to the fuel cells. This will cause contamination and deterioration of the fuel cell. In addition, when performing welding work so as to prevent welding droplets from adhering to the fuel cell, it is inferior from the viewpoint of workability, and the operator may be damaged or deteriorated by contacting the fuel cell. was there.

  On the other hand, in the aspect concerning this invention, the edge part of 1st piping and 2nd piping is inserted in the connection member connected so that each gas flow path may continue, and the inside of a connection member and 1st The first pipe and the end of the second pipe are connected. Thereby, the 1st piping and the 2nd piping can be connected without using a pipe joint.

  In particular, in the aspect according to the present invention, since the connection member is provided so as to shield the inside of the connection member and the fuel cell, the first pipe and the second pipe are provided inside the connection member whose periphery is covered. The end of the pipe and the inside of the connecting member can be welded together. For this reason, it can suppress that a welding splash disperses to a fuel cell, and can suppress that a fuel cell is contaminated.

  In particular, in the aspect according to the present invention, one side of the module container is opened, and the first pipe and the second pipe are also located on the one side, so that the welding work from the outside of the module container is performed from one side opened. Can do. Thereby, workability | operativity can be improved, suppressing the risk that an operator contacts a fuel cell.

  As described above, in the aspect according to the present invention, it is possible to realize improvement in manufacturability and further cost reduction while suppressing contamination / deterioration of the fuel cell in manufacturing the fuel cell module.

  Here, “communication” in this specification indicates a state in which fluids are connected so as to circulate. 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 connection member.

  Here, in this specification, “welded joint” means that heat and / or pressure is applied to a joint part of two or more members, a filler material is added if necessary, and the joint part is integrated with continuity. The state joined by the joining method used as one member made is shown. For example, fusion welding, pressure welding, and brazing are also included in “welded joining”.

  In one embodiment of the present invention, the connection member main body is formed in a rectangular parallelepiped shape, the connection member main body has an open surface on a side different from the side on which the plurality of fuel cells are arranged, and the open surface is a connection portion lid. It is preferable that the body is covered.

  According to this aspect, the entire surface of the rectangular parallelepiped connecting member main body is opened. The welding work for the connecting member is performed from the outside of the module container, so the workability is poor, but since the entire surface of the connecting member main body is open, the welding work inside the connecting member from the outside of one side of the module container is easy. It becomes. That is, contamination and deterioration of the fuel battery cell can be suppressed while facilitating manufacture.

  In one embodiment of the present invention, the connection member body preferably has an open surface on one side surface.

  In a joining operation from other than one side, a joining tool (for example, a welding torch) does not reach and there is a possibility that the welding operation becomes difficult. However, according to this aspect, since the open side surface of the module container and the open surface of the connection member main body are the same side, welding work inside the connection member main body is facilitated from the outside of the one side surface, and workability is improved. To do.

  In addition, since the connection member main body is open only on the surface facing the surfaces on the side of the plurality of fuel cells, welding droplets adhere to the fuel cells during the welding operation of the first pipe and the second pipe. This can be surely prevented. Furthermore, since the connection member main body and the connection member lid are located on one side surface, it is possible to prevent welding splashes from being attached to the fuel cell by welding the connection member lid to the connection member main body. Contamination and deterioration can be suppressed.

  Moreover, in one aspect of the present invention, the connection member lid is provided on the inner side of the open surface of the connection member main body, and the connection member main body is connected to the main surface for closing the open surface and the outer surface of the main surface. It is preferable that the end portion of the open surface and the end portion of the folded portion are welded to each other.

  According to this aspect, the end of the connection portion main body and the end of the connection portion lid are welded. That is, since each edge part is located in one side surface side, joining of a connection part main body and a connection part cover body can be performed from one side surface side. As a result, welding work can be performed on one side, and it is possible to prevent welding splashes from adhering to the fuel cell at the time of welding joining. It is possible to simultaneously prevent contamination and deterioration.

  In one embodiment of the present invention, it is preferable that the flow path cross-sectional area of the connection member is larger than the flow path cross-sectional area of the first pipe and / or the second pipe.

  According to this aspect, the flow path cross-sectional area of the connecting member is configured to be larger than that of the fuel gas supply pipe, so that the mixing section that uniformizes the reform variation and the supply amount variation inside the reformer Function as. Thereby, fuel gas can be supplied equally to a plurality of fuel cells. Further, even when a pressure fluctuation occurs in the fuel gas supply pipe due to an abnormality in the fuel supply source, the inside of the connecting member functions as a buffer, so that the downstream fuel cell is not affected.

  In one aspect of the present invention, it is preferable that a combustion chamber is formed above the plurality of fuel cells, and the connection member is positioned at a height of the combustion chamber.

  According to this aspect, since the connection member is located above the fuel battery cell, welding work can be performed on the connection member at a position away from the fuel battery cell, and welding droplets are prevented from adhering to the fuel battery cell. It becomes possible. Further, the fuel gas flowing through the connection member can effectively receive heat from the combustion chamber.

  In one embodiment of the present invention, it is preferable that an insertion hole is formed in the connection member main body, 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 protrude toward the inside of the connection member main body, the fuel gas supply pipe and the insertion hole provided in the connection member main body inside the connection member It becomes easy to weld and join the vicinity and the manufacturing workability is improved.

  Moreover, in one aspect of the present invention, the hydrodesulfurizer is provided with a hydrodesulfurizer to which a part of the fuel gas generated in the reformer is supplied, and the hydrodesulfurizer pipe for supplying the fuel gas to the hydrodesulfurizer is a connecting member It is preferable to be joined to the main body or the connecting member lid.

  When the hydrodesulfurizer pipe is attached to the reformer, it is necessary to take out the reformed fuel gas, so it is necessary to dispose the reformer downstream. 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 hydrodesulfurizer piping. According to this aspect, since the hydrodesulfurizer pipe is provided in the connecting member after passing through the reformer, it can be reliably supplied regardless of the gas flow rate or the reformer shape.

  In a solid oxide fuel cell device having a module container in which a reformer is fixed and a plurality of fuel cells are inserted from side openings, contamination and deterioration of the fuel cells in manufacturing a fuel cell module Thus, it is possible to provide a solid oxide fuel cell device for realizing improvement in manufacturability and further cost reduction while suppressing.

It is a perspective view which shows the fuel cell module in one Embodiment of this invention. It is side surface sectional drawing which shows the fuel cell module which has a 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 fragmentary sectional view which shows the connection member in one Embodiment of this invention. It is partial sectional drawing (A), (B), and (C) which show the process of welding-connecting the connection member and fuel gas supply pipe | tube in one Embodiment of this invention. 1 is an overall configuration diagram showing a solid oxide fuel cell apparatus (SOFC) according to an embodiment of the present 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 III-III line of FIG. It is a disassembled perspective view of a module container and an air passage cover. It is a perspective view which shows the inner surface of the closing side plate which comprises a module container. It is a perspective view which shows the periphery of the connection member in an assembly state. 1 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. FIG. 8 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. 9 is a cross-sectional view taken along line III-III in FIG. 7, similar to FIG. 8.

  Hereinafter, embodiments of the invention disclosed in this specification will be described in detail with reference to the drawings. From the following description, many modifications and other embodiments of the present invention are apparent to persons skilled in the art. Accordingly, the following description is to be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. Details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

  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 viewed from the W direction. 4 is a partial cross-sectional view showing an internal structure of a module container 1018. FIG.

  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 includes a plurality of fuel cell cells 1012 provided above a gas manifold 1004 provided inside the module container 1018 and provided inside the module container 1018. The reformer 1024 is provided.

  The reformer 1024 is supplied with raw fuel gas and steam (not shown), and generates fuel gas 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 into 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 cells 1012, and the fuel is sealed inside the gas manifold 1004 closed by the lower support plate 1010. Gas is supplied to the plurality of fuel cells 1012.

  Further, the power generation air (oxidant 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. Thereafter, the power generation air is supplied to the power generation chamber 1008 from the 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 fuel gas. The power generation air and fuel gas that did not contribute to power generation are combusted in the combustion chamber 1030 provided above and discharged from the exhaust passage 1032 to the outside of the module container 1018.

  Here, as shown in FIG. 1, the rectangular parallelepiped module container 1018 includes a module container main body 1014 and a closed side plate (module container lid) 1020. A reformer 1024 extending in the longitudinal direction (L direction) of the module container main body 1014 is fixed to the inner wall surface of the module container main body 1014 above the inside of the module container main 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 manner.

  As shown in FIGS. 1 and 2, the module container main body 1014 has one open side surface 1016, and the module container main body extends from the one side surface 1016 with the fuel cell 1012 disposed above the gas manifold 1004. It is inserted into the inside of 1014 in a sliding manner (black arrow in FIG. 2). After the fuel cell 1012 is arranged in the module container main body 1014, one side surface 1016 of the module container main body 1014 is closed by a closing side plate (module container lid) 1020 (black arrow in FIG. 1). Here, the module container body 1014 and the closed side plate 1020 are joined together by welding, whereby the inside of the module container 1018 is hermetically maintained.

  After the fuel cell 1012 is inserted into the module container body 1014, only the closed side plate (module container lid) 1020 may be welded to the module container body 1014, and after the fuel cell 1012 is stored inside By minimizing the welding operation, it is possible to suppress the risk of welding droplets adhering to the fuel battery cell 1012.

  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. A fuel gas supply pipe 1006 as a fuel gas passage hangs between the closed side plate 1020 and the plurality of fuel cells 1012, bends near the bottom of the module container 1018, and is formed below the plurality of fuel cells 1012. 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 connection member 1036 (described in detail later). The fuel gas that has passed through the first pipe 1006A passes through the inside of the connection member 1036, and then flows into the gas manifold through the second pipe 1006B so that the fuel gas that flows through the inside communicates ( (Dotted arrow in FIG. 2).

  Next, the connection 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 connection member main body 1038 connected to the first pipe 1006A and the second pipe 1006B, and the connection member lid 1040.

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

  The connection member lid 1040 closes the open surface 1038D of the connection member main body 1038. The connecting member lid 1040 includes a quadrilateral main body 1040A and a folded portion 1040B extending from the edge of the main body. The folded portion 1040 </ b> B extends to the outside of the connection member 1036.

  In the connection member main body 1030, the open surface 1038D is closed by the connection member lid 1040 after the ends of the first pipe 1006A and the second pipe 1006B are fixed to the insertion hole 1038E. Thereby, the inside of the connection member 1036 can be hermetically sealed, and the fuel gas flowing through the first pipe 1006A and the second pipe 1006B can be communicated.

  Note that the connection member 1036 is preferably made of the same material as that of the module container 1018. Thereby, it can suppress that the connection member 1036 heat-deteriorates.

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

  First, the first pipe 1006A is inserted into an 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 toward the inside of the connection 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 joined by welding ( Black portion 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 operation of the first pipe 1006A and the insertion hole 1038E inside the connection member main body 1038 is performed. Becomes easy.

  Similarly, the second pipe 1006B is inserted into an 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 toward the inside of the connection 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 joined by welding ( Black portion 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 operation between the second pipe 1006B and the insertion hole 1038E inside the connection member main body 1038. Becomes easy.

  In this way, the welding operation between the first piping 1006A and the second piping 1006B inside the connection member 1036 and the edge of the insertion hole 1038E is facilitated. Furthermore, since welding is performed inside the connecting member 1038 whose periphery other than the open surface 1038D is covered, it is possible to suppress splashing of the fuel cell 1012 side, improving workability, and improving the scattering fuel cell 1012. Both pollution and deterioration can be achieved.

  Although not shown in the present embodiment, it is also preferable to provide a hydrodesulfurizer pipe for supplying hydrogen to the hydrodesulfurizer in the connection member 1036. When the hydrodesulfurizer pipe is attached to the reformer 1024, it is necessary to take out the reformed fuel gas, and therefore it is necessary to dispose the reformer 1024 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 hydrodesulfurizer piping. According to this embodiment, since the hydrodesulfurizer pipe is provided in the connecting member 1036 after passing through the reformer 1024, the fuel gas is disposed in the hydrodesulfurizer regardless of the gas flow rate or the reformer shape. Can be supplied to. Furthermore, according to the connection member 1036 of the present embodiment, it is possible to prevent scattering of welding splashes when welding the hydrodesulfurizer pipe, so that the fuel cell 1012 can be attached while suppressing contamination and deterioration. It becomes. Note that any surface other than the fuel cell 1012 may be attached to any surface of the connection member 1036.

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

  Thus, since the end of the open surface 1038 and the end of the folded portion 1040B are configured to coincide with each other on one side 1016, these welding operations are performed from the outside of the one side 1011 of the module container 1018. This makes it possible to improve the workability. Furthermore, since welding work on the side surface 1016 side becomes possible, the connection member 1036 can suppress welding droplets during 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 configured to be larger than the flow path cross-sectional areas of the first pipe 1006A and the second pipe 1006B.

  As a result, the fuel gas generated in the reformer 1024 is further mixed in the connection member 1036 having a space larger than the pipe line, and variations in fuel gas reforming and variations in the amount of supplied fuel gas are caused in the connection member 1036. It can be made uniform. Furthermore, even when pressure fluctuations occur in the piping due to abnormal fuel gas supply or the like, the inside of the connection member 1036 functions as a buffer, so that the fuel cell 1012 is not affected.

  Note that the inner diameters D1 and D2 of the first pipe 1006A and the second pipe 1006B may be configured to be smaller than the inner diameter D1 of the connection 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 connection member 1036 can be appropriately adjusted according to the length of the folded portion 1040B.

  Next, a manufacturing process until the connection member 1036 is configured will be described with reference to FIG. FIG. 5A shows a cross-sectional view when the fuel cell 1012 having the gas manifold 1004 is inserted into the module container main body 1014 in a sliding manner. FIG. 5B is a cross-sectional view when the first pipe 1006A and the second pipe 1006B are welded to the connection member main body 1038. FIG. 5C is a cross-sectional view when the connection member lid 1040 is welded to the connection member main body 1038.

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

  After the insertion, as shown in FIG. 5B, the first pipe 1006A is inserted into the insertion hole 1038E of the connection member main body 1038 by sliding the connection member main body 1038 upward (dotted arrow in FIG. 5B). And the 2nd piping 1006B can be inserted. As a result, when attaching the connection member main body 1038 to the first pipe 1006A and the second pipe 1006B, it is attached while avoiding contact with surrounding parts such as the fuel cell 1012 and suppressing damage and deterioration of the parts. Is possible.

  As shown in FIG. 5B, after the first pipe 1006A and the second pipe 1006B are inserted into the insertion hole 1038E of the connection member main body 1038, these are welded and joined inside the connection member main body 1038 ( Black in FIG. 5B). Here, the inside of the connection member main body 1038 and the fuel cell 1012 are shielded, and the welding splashes between the first pipe 1006A and the second pipe 1006B and the connection member main body 1038 are completely blocked by the joining member. For this reason, the contamination / deterioration of the fuel battery cell 1012 associated with the welding joint can be reliably suppressed.

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

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

  Further, as shown in FIG. 5C, the connection member 1036 is located at the height of the combustion unit 1030. Thereby, since the connection member 1036 and the combustion chamber 1030 are close to each other, the fuel gas flowing inside can receive heat directly from the combustion chamber 1030, and the temperature of the fuel gas can be effectively increased. Furthermore, since it is arranged at a position away from the fuel cell 1012, it is possible to suppress the risk that the welding splash generated by the joining member 1036 is scattered in the fuel cell.

Next, a solid oxide fuel cell device according to an 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 apparatus (SOFC) according to an embodiment of the present invention. As shown in FIG. 6, a solid oxide fuel cell apparatus (SOFC) 1 according to an embodiment of the present invention includes a fuel cell module 2 and an auxiliary 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 the lower portion of the module container 8, which is a sealed space, a fuel cell that performs a power generation reaction using fuel gas and oxidant gas (hereinafter referred to as “power generation air” or “air” as appropriate). A cell assembly 12 is accommodated. The fuel cell assembly 12 includes a plurality of fuel cell units 16 connected in series.

  A combustion chamber 18 as a combustion section is formed above the power generation chamber 10 of the module container 8 of the fuel cell module 2, and in this combustion chamber 18, the remainder not used for power generation reaction (which did not contribute to power generation) The fuel gas and the remaining air are combusted to generate exhaust gas (in other words, combustion gas). Furthermore, the module container 8 is covered with the heat insulating material 7, and the heat inside the fuel cell module 2 is suppressed from being diffused to the outside air. Further, a reformer 120 for reforming the fuel gas is disposed above the combustion chamber 18, and the reformer 120 is heated to a temperature at which a reforming reaction can be performed by the combustion heat of the residual gas. Yes.

  Further, an evaporator 140 is provided in the heat insulating material 7 above the module container 8 in the housing 6. The evaporator 140 performs heat exchange between the supplied water and the exhaust gas, thereby evaporating the water to generate water vapor, and a mixed gas (hereinafter referred to as “fuel gas”) of the water vapor and the raw fuel gas. Is supplied to the reformer 120 in the module container 8.

  Next, the auxiliary unit 4 stores pure water tank 26 that stores water condensed from moisture contained in the exhaust from the fuel cell module 2 and makes it pure water with a filter, and water supplied from the water storage tank. Is provided with a water flow rate adjusting unit 28 (such as a “water pump” driven by a motor). The auxiliary unit 4 includes a gas shutoff valve 32 that shuts off the fuel supplied from the fuel supply source 30 that is a reduction in the supply of raw material gas such as city gas, and a desulfurizer 36 that removes sulfur from the fuel gas. A fuel flow rate adjusting unit 38 (such as a “fuel pump” driven by a motor) for adjusting the flow rate of the fuel gas, and a valve 39 for shutting off the fuel gas flowing out from the fuel flow rate adjusting unit 38 when the power is lost. Yes. Further, the auxiliary 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). Driven "air blower", etc., a first heater 46 for heating the reforming air supplied to the reformer 120, and a second heater 48 for heating the power generating air supplied to the power generation chamber. I have. The first heater 46 and the second heater 48 are provided in order to efficiently raise the temperature at startup, but may be omitted. In this embodiment, the desulfurizer 36 is a hydrodesulfurizer that supplies hydrogen to cause a desulfurization reaction.

  In this embodiment, the partial oxidation reforming reaction (POX) and the steam reforming reaction (SR) are performed from the POX process in which only the partial oxidation reforming reaction (POX) occurs in the reformer 120 when the apparatus is started. The SR process in which only the steam reforming reaction is performed may be performed through the ATR process in which the mixed autothermal reforming reaction (ATR) occurs, or the POX process may be omitted and the ATR process may be changed to the SR process. You may comprise so that it may transfer, and it may comprise so that a POX process and an ATR process may be abbreviate | omitted and only an SR process may be performed. In the configuration in which only the SR step is performed, the reforming air flow rate adjustment unit 44 is unnecessary.

  Next, a hot water production apparatus 50 to which exhaust gas is supplied is connected to the fuel cell module 2. The hot water production apparatus 50 is supplied with tap water from the water supply source 24, and the tap water is heated by the heat of the exhaust gas and supplied to a hot water storage tank of an external hot water heater (not shown). The fuel cell module 2 is provided with a control box 52 for controlling the amount of fuel gas supplied and the like. Furthermore, the fuel cell module 2 is connected to an inverter 54 that is a power extraction unit (power conversion unit) for supplying the 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 one embodiment of the present invention will be described with reference to FIGS. 7 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, and FIG. 8 is a sectional view taken along line III-III in 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 includes a fuel cell assembly 12 and a reformer 120 provided inside the module container 8 covered with the heat insulating material 7, and the module container 8. And an evaporator 140 provided in the heat insulating material 7.

  First, as shown in FIG. 9, the module container 8 includes a substantially rectangular top plate 8a, bottom plate 8c, and a pair of opposing side plates 8b that connect the sides extending in the longitudinal direction (left-right direction in FIG. 7). A closed side plate that closes two opposing openings at both ends in the longitudinal direction of the cylindrical body and connects the sides extending in the width direction (the left-right direction in FIG. 8) of the top plate 8a and the bottom plate 8c. 8d and 8e.

  In the module container 8, the top plate 8 a and the side plate 8 b are covered with an air passage cover 160. The air passage cover 160 includes a top plate 160a and a pair of opposing side plates 160b. An opening 167 for passing through the exhaust pipe 171 and an opening 160c for connecting the power generation air introduction pipe 74 are provided at 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. Thereby, 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 plates 160a and 160b (see FIG. 8).

  At the lower part of the side plate 8b of the module container 8, air outlets 8f that are a plurality of through holes 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 power generation air is injected into the power generation chamber 10 through the air passages 161a and 161b from the outlet 8f toward the fuel cell assembly 12 (see FIGS. 8 and 9).

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

  In addition, the air passages 161a and 161b have heat exchange promoting members that promote 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 8 a of the module container 8 and the top plate 160 a of the air passage cover 160. That is, the plate fin 162 is provided in a portion corresponding to a later-described first exhaust passage 172a in the air passage 161a. Further, the plate fin 163 extends between the side plate 8b of the module container 8 and the side plate 160b of the air passage cover 160 and extends above the fuel cell unit 16 in the longitudinal direction and the vertical direction. Is provided. That is, the plate fins 163 are provided in portions corresponding to a second exhaust passage 172b and an exhaust concentration portion 176, which will be described later, in the air passage 161b.

  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 plate 8b), particularly when passing through the plate fins 162 and 163. Heat exchange is performed with the exhaust gas passing through the exhaust passage). For this reason, the portions where the plate fins 162 and 163 are provided in the air passages 161a and 161b function as a heat exchanger (heat exchange section). The portion provided with the plate fins 162 constitutes a main heat exchanger portion, and the portion provided with the plate fins 163 constitutes a subordinate heat exchanger portion.

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

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

  Further, as shown in FIGS. 7 and 8, the evaporator 140 has an evaporator case 141 that is substantially rectangular in top view. The evaporator case 141 is formed by joining two low-profile bottomed rectangular cylindrical upper case 142 and lower case 143 with an intermediate plate 144 sandwiched therebetween.

  Accordingly, 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 a fuel layer is formed in the upper layer portion. An evaporation unit 140B that evaporates water supplied from the supply pipe 63 to generate water vapor, and a mixing unit 140C that mixes the water vapor generated in the evaporation unit 140B and the raw fuel gas supplied from the fuel supply pipe 63 are provided. It has been.

  The evaporator 140B and the mixer 140C are formed in a space where the evaporator 140 is partitioned by a partition plate provided with a plurality of communication holes (slits). The evaporation unit 140B is filled with alumina balls (not shown).

  Similarly, the exhaust passage portion 140A is 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. The second space is filled with a combustion catalyst (not shown). That is, the evaporator 140 of the present embodiment includes a combustion catalyst device.

  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 is evaporated by 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 a mixed gas to the reformer 120 is connected to the mixing unit 140C. The mixed gas supply pipe 112 is disposed so as to pass through the inside of the exhaust pipe 171, one end is connected to an opening 144 a formed in the intermediate plate 144, and the other end is formed on the top surface of the reformer 120. 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 into the module container 8, where it is bent approximately 90 ° and extends horizontally along the top plate 8a. , Bent downward by approximately 90 ° and connected to the reformer 120.

  Next, the reformer 120 is disposed above the combustion chamber 18 so as to extend in the horizontal direction along the longitudinal direction of the module container 8, and the exhaust gas guiding member 130 is interposed between the reformer 120 and the top plate 8 a of the module container 8. And fixed to the top plate 8a with a predetermined distance therebetween. The reformer 120 has a substantially rectangular outer shape in a top view, but is an annular structure in which a through hole 120b is formed in the center, and has a casing in which an upper case 121 and a lower case 122 are joined. ing. The through hole 120b is positioned 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 in the longitudinal direction of the reformer 120 (closed side plate 8e side of the module container 8), 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 ( On the closed side plate 8 d side), the fuel gas supply pipe 64 is connected to the lower case 122. Therefore, the reformer 120 receives the mixed gas (that is, raw fuel gas mixed with water vapor (may include reforming air)) from the mixed gas supply pipe 112, reforms the mixed gas therein, The reformed gas (ie, fuel gas) is discharged from the fuel gas supply pipe 64.

  The reformer 120 is divided into three spaces by the two partition plates 123a and 123b, so that the reformer 120 receives a mixed gas from the mixed gas supply pipe 112 in the reformer 120. And a reforming section 120B filled with a reforming catalyst (not shown) for reforming the mixed gas, and a gas discharge section 120C for discharging the gas that has passed through the reforming section 120B are formed. (See FIG. 7). The reforming unit 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 are movable through a plurality of communication holes (slits) provided in the partition plates 123a and 123b. As the reforming catalyst, a catalyst obtained by imparting nickel to the alumina sphere surface or a catalyst obtained by imparting ruthenium to the alumina sphere surface is appropriately used.

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

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

  A fuel gas supply pipe 64 as a fuel gas supply passage extends downward in the module container 8 along the closed side plate 8d, bends approximately 90 ° in the vicinity of the bottom plate 8c, and extends in the horizontal direction. The gas gas manifold 66 is formed in the lower part of the gas gas manifold 66 and extends in the horizontal direction to the vicinity of the closed 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. The first pipe 64A and The second pipe 64 </ b> B is configured so that the inside of the pipe communicates with the connection member 190. The connecting member 190 is provided substantially at the height of the combustion portion and is located obliquely above the fuel cell assembly 12.

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

  A plurality of fuel supply holes 64 b are formed in the lower surface of the horizontal portion 64 a of the fuel gas supply pipe 64, and fuel gas is supplied into the gas gas manifold 66 from the fuel supply holes 64 b. 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 enters the fuel cell unit 16. Supplied. An ignition device 83 for starting combustion of fuel gas and air is provided in the combustion chamber 18.

  Further, the entire circumference of the first pipe 64A and the second pipe 64B is surrounded by the connecting member 190. FIG. 11 is an enlarged vertical sectional view of the fuel supply pipe 64 in a state where the connection member 190 is attached.

  FIG. 11 is a perspective view showing the periphery of the connection 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. And in the state which closed the closed side board 8d, the connection member 190 is accommodated in the groove part 180C of the closed side board 8d. The surface of the connecting member 190 on the fuel cell unit 16 side is located on the same plane as the projecting surfaces of the first protruding portion 180A and the second protruding portion 180B of the closing side plate 8d on the fuel cell unit 16 side. . Thereby, it can suppress that the air for electric power generation in the electric power generation chamber 10 flows out into the groove part 180C, and can suppress that the airflow of the electric power generation chamber 10 and the combustion chamber 18 is disturbed.

  A fuel gas supply pipe 64 as a fuel gas supply passage extends downward in the module container 8 along the closed side plate 8d, bends approximately 90 ° in the vicinity of the bottom plate 8c, and extends in the horizontal direction. The gas gas manifold 66 is formed in the lower part of the gas gas manifold 66 and extends in the horizontal direction to the vicinity of the closed side plate 8e on the opposite side. A plurality of fuel supply holes 64 b are formed in the lower surface of the horizontal portion 64 a of the fuel gas supply pipe 64, and fuel gas is supplied into the gas gas manifold 66 from the fuel supply holes 64 b. 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 enters the fuel cell unit 16. Supplied. 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 disposed between the reformer 120 and the top plate 8 a so as to extend in the horizontal direction along the longitudinal direction of the module container 8. The exhaust gas guide member 130 includes a lower guide plate 131 and an upper guide plate 132 that are separated by a predetermined distance in the vertical direction, and connecting plates 133 and 134 to which both ends of the longitudinal direction are attached (FIG. 7). FIG. 8). The upper guide plate 132 is bent at both ends in the width direction downward and is connected to the lower guide plate 131. The connecting plates 133 and 134 have upper ends connected to the top plate 8a and lower ends connected to the reformer 120, thereby fixing the exhaust gas guiding member 130 and the reformer 120 to the top plate 8a. ing.

  The lower guide plate 131 is formed with a convex step portion 131a in which a central portion in the width direction (left-right direction in FIG. 8) protrudes downward. On the other hand, as with the lower guide plate 131, the upper guide plate 132 is formed with a recess 132a so that the central portion in the width direction becomes 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 in the recess 132a in the module container 8 in the horizontal direction, then bends downward near the closed side plate 8e, passes through 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, a gas reservoir (gas heat insulating layer) 135, which is an internal space that functions as a heat insulating layer, is formed by the upper guide plate 132, the lower guide plate 131, and the connecting plates 133 and 134. The gas reservoir 135 is in fluid communication with the combustion chamber 18. 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. While it is possible for exhaust gas to flow into the gas reservoir 135 from the combustion chamber 18 during operation, or to allow air to flow in from the outside when stopped, the movement of gas between the inside and outside of the gas reservoir 135 is generally performed. Is moderate.

  The upper guide plate 132 is disposed at a predetermined vertical distance from the top plate 8a. Between the upper surface of the upper guide plate 132 and the top plate 8a, the upper guide plate 132 is horizontally aligned along the longitudinal direction and the width direction. An extended 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. In the first exhaust passage 172a, plate fins 162, 163 in the air passages 161a, 161b and Similar plate fins 175a are arranged. The plate fins 175a are provided at substantially the same location as the plate fins 162 when viewed from above, and face each other in the vertical direction across the top plate 8a.

  The upper guide plate 132 is disposed 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 extended second exhaust passage 172b is formed. The second exhaust passage 172b communicates with the first exhaust passage 172a at the top. Also in the second exhaust passage 172b, plate fins 175b similar to the plate fins 162 and 163 in the air passages 161a and 161b are arranged. The lower end of the plate fin 175b extends to the height of the lower guide plate 131.

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

  The reformer 120 is disposed at a predetermined horizontal distance from the side plate 8b of the module container 8, and the exhaust gas passes between the reformer 120 and the side plate 8b from below to above. A third exhaust passage 173 is formed.

  Further, the lower guide plate 131 is disposed at a predetermined vertical distance from the top surface of the upper case 121 of the reformer 120, and between the lower guide plate 131 and the upper case 121 and the reformer. The 120 through-hole 120b forms a fourth exhaust passage 174 through which the exhaust gas that has passed through the through-hole 120b from the bottom to the top 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 to form an exhaust concentration portion 176 where exhaust gas concentrates.

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 that are caps respectively connected to both ends of the fuel cell 84.

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

  Since the inner electrode terminal 86 attached to the upper end side and the lower end side of the fuel cell 84 has the same structure, the inner electrode terminal 86 attached to the upper end side will be specifically described here. The upper portion 90 a of the inner electrode layer 90 includes an outer peripheral surface 90 b and an upper end surface 90 c 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 through a conductive sealing material 96, and is further in direct contact with the upper end surface 90c of the inner electrode layer 90, thereby Electrically connected. At the center of the inner electrode terminal 86, a fuel gas channel capillary 98 that communicates with the fuel gas channel 88 of the inner electrode layer 90 is formed.

  The fuel gas passage narrow 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 occurs in the flow of the 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 narrow tube 98 of the lower inner electrode terminal 86. Occur. Accordingly, the fuel gas flow passage narrow tube 98 of the lower inner electrode terminal 86 acts as an inflow side flow passage resistance portion, and the flow passage 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 to the combustion chamber 18 (see FIG. 7) through the fuel gas flow path narrow tube 98 of the upper inner electrode terminal 86. Therefore, the fuel gas flow passage narrow tube 98 of the upper inner electrode terminal 86 acts as an outflow side flow passage resistance portion, and the flow passage resistance is set to a predetermined value.

  The inner electrode layer 90 includes, 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. The mixture is formed of at least one of Ni and a mixture of lanthanum garade doped with at least one selected from Sr, Mg, Co, Fe, and Cu.

  The electrolyte layer 94 includes, 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, lanthanum gallate doped with at least one selected from Sr and Mg, Formed from at least one of the following.

  The outer electrode layer 92 includes, for example, lanthanum manganite doped with at least one selected from Sr and Ca, 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 lanthanum cobaltite doped with at least one selected from the group consisting of silver and silver.

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

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

  As shown in FIG. 13, water and raw fuel gas (fuel gas) are fed into an evaporation section 140 </ b> B provided in an 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. 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 water vapor. The water vapor and the raw fuel gas supplied from the fuel supply pipe 63 flow downstream in the evaporation unit 140B and are mixed in the mixing unit 140C. The mixed gas in the mixing section 140C is heated by the exhaust gas flowing through the lower exhaust passage section 140A.

  The mixed gas (fuel gas) formed in the mixing unit 140 </ b> C 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 mixed gas in the mixed gas supply pipe 112 is further increased by the exhaust gas flowing through these passages. Heated.

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

  Further, the fuel gas that has flowed into the fuel gas supply pipe 64 (first pipe 64A) from the gas discharge part 120C is supplied into the connection member 190. In the connection member 190, the fuel gas supply pipe 64 (second pipe 64B) and the hydrodesulfurizer 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 each fuel cell is supplied from the gas gas manifold 66. It is supplied into the unit 16.

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

  Thereafter, the power generation air is injected into the power generation chamber 10 from the plurality of outlets 8 f provided at the lower portion of the side plate 8 b of the module container 8 toward the fuel cell assembly 12. In the present embodiment, since the exhaust passage is not formed in the side 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 side part 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 combusted in the combustion chamber 18 to become exhaust gas (combustion gas), and rises in the module container 8. Specifically, the exhaust gas is branched into a third exhaust passage 173 and a fourth exhaust passage 174, and between the outer surface of the reformer 120 and the side plate 8 b of the module container 8 and the reformer 120. The through-hole 120b passes between the reformer 120 and the exhaust gas guiding member 130. At this time, the exhaust gas passing through the fourth exhaust passage 174 is bisected in the width direction by the convex step portion 131a disposed above the through hole 120b of the reformer 120, and remains in the lower portion of the exhaust gas guiding member 130. Without being guided toward the third exhaust passage 173, the exhaust concentration portion 176 joins the exhaust gas flowing through the third exhaust passage 173. 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 section 176 (A in FIG. 14). Part).

  Thereafter, the exhaust gas is introduced from the exhaust concentration portion 176 into the second exhaust passage 172b. The exhaust gas that has passed through the second exhaust passage 172 b flows in the horizontal direction through the first exhaust passage 172 a and flows out from the exhaust port 111 formed at the center of the top plate 8 a of the module container 8.

  When the exhaust gas stays in the exhaust concentration 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 concentration portion 176 in the air passage 161b. Exchange is performed. 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. Through the plate fins 162 and 163 provided at portions corresponding to the inner plate fins 175b and 175a, efficient heat exchange is performed between the power generation air and the exhaust gas. In this way, the temperature of the power generation air is raised by the heat of the exhaust gas.

  The exhaust gas flowing out from the exhaust port 111 passes through the exhaust pipe 171 provided outside the module container 8, flows into the exhaust passage part 140A of the evaporator 140, passes through the exhaust passage part 140A, and then evaporates. From the vessel 140 to the exhaust gas discharge pipe 82. As described above, the exhaust gas exchanges heat with the mixed gas in the mixing section 140C of the evaporator 140 and the water in the evaporation section 140B when flowing through the exhaust passage section 140A of the evaporator 140.

DESCRIPTION OF SYMBOLS 1 Solid oxide fuel cell apparatus 2 Fuel cell module 4 Auxiliary machine unit 6 Housing 7 Heat insulating 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 unit 18 Combustion chamber 24 Water supply source 26 Pure water tank 28 Water flow rate adjustment unit 30 Fuel supply source 32 Gas shut-off valve 36 Desulfurizer (hydrogenated desulfurizer)
38 Fuel flow rate adjustment unit 39 Valve 40 Air supply source 42 Solenoid valve 44 Reforming air flow rate adjustment unit 45 Power generation air flow rate adjustment unit 46 First heater 48 Second heater 50 Hot water production device 52 Control box 54 Inverter 63 Fuel supply piping 64 Fuel gas supply pipe 64a Horizontal portion 64b Fuel supply hole 65 Hydrodesulfurization 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 86 Inside 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 narrow tube 111 Exhaust port 112 Mixed gas supply pipe 120 Reformer 120A Mixed gas receiving part 120B Reformed part 120C Gas exhaust 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 the lower guide plate 131a projecting shoulder 132 the upper guide plate 132a recess 133 connecting plate 134 connecting plate 135 gas insulation layer (gas reservoir)
140 Evaporator 140A Exhaust passage part 140B Evaporation part 140C Mixing part 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 adjusting portion 167 Opening portion 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 portion 180A First protrusion 180B First Two projections 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 Insertion hole 1040 Connection member lid 1040A Main unit 1040B Folding part

Claims (8)

A solid oxide fuel cell device comprising a plurality of fuel cells that generate electricity by a power generation reaction between a fuel gas and an oxidant gas,
A rectangular parallelepiped module container in which the plurality of fuel cells are housed and at least one side surface is opened;
A module container lid covering the one side surface;
A reformer fixed to the module container and disposed above the module container;
A gas manifold that is provided below the inside of the module container and supplies the fuel gas generated by the reformer to the plurality of fuel cells standing on the upper surface;
A first pipe that is arranged on the one side surface and that allows fuel gas to flow out from the connected reformer;
A second pipe arranged on the one side surface and allowing fuel gas to flow into the connected gas manifold;
Ends of the first pipe and the second pipe are inserted, and a connection member that communicates the first pipe and the second pipe;
With
The connection member includes a connection member body that shields the inside of the connection member and the plurality of fuel cells, and a connection member lid.
The solid oxide fuel cell device, wherein the first pipe and the second pipe are welded to the connection member main body inside the connection member.   The connection member main body is formed in a rectangular parallelepiped shape, the connection member main body has an open surface on a side different from a side on which the plurality of fuel cells are arranged, and the open surface is covered with the connection portion lid. The solid oxide fuel cell device according to claim 1, wherein the solid oxide fuel cell device is provided.   The fuel cell device according to claim 2, wherein the connection member main body has the open surface on the one side surface side.   The connection member lid is provided on the inner side of the open surface of the connection member main body, and the connection member cover has a main surface for closing the open surface, and an outer periphery of the main surface of the connection member main body. 4. The solid oxide according to claim 3, further comprising: a folded portion that protrudes toward the one side surface, wherein an end portion of the open surface and an end portion of the folded portion are weld-joined. Fuel cell device.   5. The solid oxide fuel cell according to claim 4, wherein a flow path cross-sectional area of the connection member is larger than a flow path cross-sectional area of the first pipe and / or the second pipe. apparatus.   6. The solid oxide fuel cell device according to claim 5, wherein a combustion chamber is formed above the plurality of fuel cells, and the connecting member is positioned at a height of the combustion chamber.   An insertion hole is formed in the connection member main body, and an end of the first pipe and / or the second pipe is located inside the insertion hole. The solid oxide fuel cell device according to any one of claims.   The hydrodesulfurizer is provided with a hydrodesulfurizer to which a part of the fuel gas generated in the reformer is supplied, and the hydrodesulfurizer pipe for supplying fuel gas to the hydrodesulfurizer is the connecting member body or the connecting member The solid oxide fuel cell device according to any one of claims 1 to 7, wherein the solid oxide fuel cell device is joined to a lid.

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