JP6587209B2 - Solid oxide fuel cell device - Google Patents

Description

  The present invention relates to a solid oxide fuel cell device, and more particularly to a solid oxide fuel cell device that generates electric power by a reaction between a fuel gas obtained by reforming a raw material gas and an oxidant gas.

  Solid Oxide Fuel Cell (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 cell is arranged to supply a fuel gas to one electrode (fuel electrode) and supply an oxidant gas (air, oxygen, etc.) to the other electrode (air electrode) to generate power by a power generation reaction. It is a device for taking out electric power and operates at a relatively high temperature such as 700 ° C., for example.

  Here, the reformer disposed above the fuel cell by the heat of the exhaust gas generated by burning the remaining fuel gas (off gas) not used for power generation among the fuel gas supplied to the fuel electrode of the fuel cell. A so-called cell burner type thermal self-supporting solid that heats and maintains the reformer temperature at a temperature that allows a predetermined reforming reaction to reform the raw fuel gas into a fuel gas and supply it to the fuel electrode Oxide fuel cell devices are extremely useful in the industry because they have a high overall energy efficiency and can simplify the device configuration by eliminating the need for an external burner that separately heats the reformer. .

  In such a solid oxide fuel cell device, conventionally, the temperature of the oxidant gas is raised using the heat of exhaust gas generated by burning off-gas, and the heated oxidant gas is supplied to the fuel cell. To be done. As a configuration for performing heat exchange between the exhaust gas and the oxidant gas, for example, Patent Document 1 discloses a heat exchange configured by an exhaust gas passage through which the combusted exhaust gas is discharged and an oxidant gas storage chamber. It is disclosed that the portion is formed above the inside of the module container that accommodates the cell stack, and the exhaust gas passage is formed along the oxidant gas accommodating chamber so that heat is exchanged in this portion.

  However, in order to sufficiently heat the oxidant gas until it is supplied to the fuel cell, the volume of the container increases significantly when the heat exchange part is arranged in the module container. This was a factor that hindered downsizing of the solid oxide fuel cell device.

  On the other hand, in Patent Document 2, an evaporator that is configured integrally with a conventional reformer and cools the inside of the module by radiation cooling during water vaporization is separated from the outside of the module container that houses the cell stack. It is disclosed to arrange.

  By arranging the evaporator separately from the outside of the module container in this way, the heat utilization rate in the module container can be improved because the heat of exhaust gas in the module container is not taken away by the evaporator. It becomes. Since it becomes possible to use high-temperature exhaust gas, the oxidant gas can be heated sufficiently even if the heat exchange area is reduced, and while maintaining and improving the performance of the fuel cell module, both miniaturization is achieved. The fuel cell device can be manufactured.

JP 2005-1000068 A JP 2012-221659 A

  As a heat exchanging part, a heat exchanging unit having a wall surface of a module container as a part of a passage as disclosed in Patent Document 2 with respect to a unit-shaped dedicated heat exchanger disposed as a separate unit. In the case of configuring a heat exchanging section using a passage (passage between cases), it can be said that it is particularly advantageous in terms of cost reduction and size reduction of the container.

  By separating the evaporator from the outside of the module container, it is possible to arrange the evaporator limited to the top surface so as to directly receive the exhaust gas rising through the heat exchanging section constituted by the passage between cases. In realizing such a configuration, the present inventors consider that the exhaust gas outlet is provided at the center of the top surface of the module container, considering the symmetry and uniformity of the distribution of the exhaust gas inside the module container. Found that is the best. Then, in order to increase the heat exchange efficiency between the oxidant gas and the exhaust gas, it is necessary to secure a sufficient heat exchange distance (heat exchange area) with the exhaust gas, so the exhaust gas inlet is at the end of the top surface of the module container. It is inevitable to install in the department.

  In the heat exchanging portion on the top surface of the module container arranged under the structural restriction of such a heat exchanging portion, the exhaust gas passage inside the module vessel extends in the horizontal plane direction. For this reason, it is necessary to change the course of the exhaust gas rising from the lower part (combustion part) in the module container so as to proceed in the horizontal direction inside the heat exchange part, but it is an inlet of the exhaust gas to the heat exchange part. Since exhaust gas concentrates in the vicinity of the exhaust gas inlet and convection occurs, smooth entry of the exhaust gas into the heat exchange section is hindered.

  One aspect of a solid oxide fuel cell device according to the present invention is a solid oxide fuel cell device using a plurality of fuel cells that generate power by reaction of a fuel gas and an oxidant gas. A rectangular parallelepiped module container, a heat insulating material that covers the periphery of the module container, a fuel gas supply passage that supplies fuel gas to a plurality of fuel cells, and a fuel container that is disposed in the module container. A reformer that reforms fuel gas and supplies it to the fuel gas supply passage, and combustion that burns fuel gas remaining in power generation of a plurality of fuel cells and heats the reformer provided above by combustion heat And an evaporator that is disposed outside the module container and in the heat insulating material, and that supplies the reformer with a mixed gas of water vapor and raw fuel gas generated by evaporating the supplied water. A heat exchange unit that is provided from one end of the top surface of the container to the other end and exchanges heat between the exhaust gas generated by the combustion of the combustion unit and the oxidant gas supplied from the outside of the module container, and the module from the heat exchange unit An exhaust gas exhaust port provided at the center of the top surface of the module container for exhausting the exhaust gas to the outside of the container, and an oxidant gas supply passage for supplying the oxidant gas discharged from the heat exchange unit to a plurality of fuel cells. The heat exchanging part has exhaust gas flowing through an exhaust gas passage formed by a top surface of the module container and a lower surface made of a plate-like member provided inside the module container, and the top surface of the module container and the module container The oxidant gas flowing through the oxidant gas passage formed by the upper surface made of a cover member provided outside the heat exchanger is configured to exchange heat via the top surface of the module container, The gas inlets are located on both sides of the pair of end portions on the top surface of the module container and are located on a surface orthogonal to the top surface of the module container, and are upstream of the heat exchange unit with respect to the flow of exhaust gas. In the vicinity of the exhaust gas inlet, an exhaust gas guiding part for guiding the exhaust gas to the exhaust gas passage is provided.

  According to the present invention configured as described above, by providing the exhaust gas induction portion at the exhaust gas introduction port of the heat exchange unit provided on the top surface of the module container, the concentration of the exhaust gas generated near the exhaust gas introduction port is caused. It has become possible to suppress the generation of convection and easily introduce exhaust gas into the exhaust gas passage in the heat exchange section. Thereby, the heat exchange function in a heat exchange part can fully be exhibited, and the heat utilization factor inside a module container can be raised.

  In one aspect of the present invention, the exhaust gas guiding portion is a corner wall of the module container in which the top surface of the module container and the side surface of the module container are connected to each other, and the exhaust gas rising inside the module container is introduced into the exhaust gas. It is preferable to have a curvature so as to face the mouth.

  At the corner corner of the module container in the vicinity where the exhaust gas inlet is provided, the direction of the rising exhaust gas is forced to change direction by the heat exchange flow path in the orthogonal direction. An increase has occurred. According to the present invention configured as described above, the corner of the module container has a curved shape, so that the direction of the rising exhaust gas is changed to a horizontal direction that is a direction perpendicular to the direction of the exhaust gas. Guides exhaust gas to the inlet. Thereby, the increase in the pressure loss near the exhaust gas inlet can be suppressed, the exhaust gas can be smoothly introduced into the heat exchange part, and high heat exchange efficiency can be ensured.

  In one embodiment of the present invention, the oxidant gas passage extends in a part of the side surface of the module container by the cover member being bent and extended from the top surface to the side surface of the module container. Is preferably smaller than the curvature of the corner wall of the cover member formed by bending.

  According to the present invention configured as described above, in order to guide the exhaust gas to the heat exchange unit, the corner corner wall of the module container provides a curvature, so that the oxidant gas is at the corner of the corresponding oxidant gas passage. Since it is guided downward along the side surface from the top surface of the module container, an increase in pressure loss at the corner can be mitigated. On the other hand, since the corner portion of the oxidant gas passage formed by bending the cover member has a large curvature, it is possible to secure a large volume of the oxidant gas passage at the location. For this reason, the increase in pressure loss at the corners can be further mitigated.

  In one embodiment of the present invention, the oxidant gas passage extends and bends to a part of the side surface of the module container by the cover member being bent and extending from the top surface to the side surface of the module container. The square walls of the cover member formed in the shape of R are R-shaped, respectively, in the oxidant gas passages formed between the cover member and the top surface of the module container and between the cover member and the side surface of the module container. In this case, a heat transfer plate that divides the oxidant gas passage into two layers of passages parallel to the wall surface of the module container is disposed, and these heat transfer plates are preferably in contact with each other at the square wall.

  According to the present invention configured as described above, the corner portion of the oxidant gas passage formed by bending the cover member is formed into an R shape, thereby maximizing the volume of the oxidant gas passage at the location. In addition, a heat transfer plate having two passages can be disposed in contact with each other at the corners of each of the oxidant gas passages located on the top and side surfaces of the module container. For this reason, since the lower layer of the oxidant gas passage is clearly divided on the top surface and the side surface, the heat exchange efficiency between the oxidant gas and the exhaust gas below the oxidant gas is increased by mainly flowing the oxidant gas to the lower layer. be able to.

  In one embodiment of the present invention, the heat transfer plate includes a main surface that divides the oxidant gas passage into two-layer passages parallel to the wall surface of the module container, and one layer to the other layer of the two-layer passages. An oxidant divided into two layers having a plurality of a plurality of protrusions and vent holes arranged on the main surface for allowing the oxidant gas to flow and conducting heat with the top surface of the module container It is preferable that the convex part of the heat transfer plate is not disposed in the lower layer portion of the corner wall of the cover member in the gas passage.

  According to the present invention configured as described above, at the corner portion of the oxidant gas passage formed by the bending of the cover member, the convex portion included in the main surface of the heat transfer plate partitioned into two layers is not positioned. By arrange | positioning, oxidizing agent gas can be mainly flowed to a lower layer in a corner | angular part. For this reason, oxidant gas can be flowed so that it may touch the wall surface of a module container, and heat exchange efficiency can be improved.

  Moreover, in one aspect of the present invention, a heat transfer plate that divides the exhaust gas passage into two-layer passages parallel to the top surface of the module container is disposed in the exhaust gas passage, and the heat transfer plate is disposed inside the heat exchange section. It is preferable that it is arranged inside the exhaust gas inlet.

  According to the present invention configured as described above, when the heat transfer plate is disposed in the vicinity of the exhaust gas inlet, the heat transfer plate functions as an obstacle to prevent the gas flow, so that pressure loss occurs at the corner where the exhaust gas flows. It will increase. Therefore, by increasing the heat transfer plate with respect to the exhaust gas inlet, the increase in pressure loss at the corner can be mitigated.

  In one embodiment of the present invention, the heat transfer plate includes a main surface that divides the exhaust gas passage into two-layer passages parallel to the top surface of the module container, and one layer to the other layer of the two-layer passages. Among the exhaust gas passages divided into two layers, which have a pair of convex portions and vent holes arranged on the main surface for allowing the exhaust gas to flow and conducting heat with the top surface of the module container, It is preferable that the convex portion of the heat transfer plate is not disposed in the vicinity of the upper layer exhaust gas inlet.

  According to the present invention configured as described above, the corner corner wall is arranged so that the convex portion included in the main surface of the heat transfer plate partitioned into two layers is not positioned, so that the exhaust gas is exhausted to the upper layer in the corner corner wall. Can be made to flow independently. For this reason, heat exchange with oxidant gas can be accelerated | stimulated by flowing waste gas so that the wall surface of a module container may be contacted, and heat exchange efficiency can be improved.

  In a solid oxide fuel cell device, by providing an exhaust gas induction part at the exhaust gas inlet of the heat exchange part provided on the top surface of the module container, convection occurs due to the concentration of the exhaust gas that has occurred near the exhaust gas inlet. This makes it possible to easily introduce exhaust gas into the exhaust gas passage in the heat exchange section. Thereby, the heat exchange function in a heat exchange part can fully be exhibited, and the heat utilization factor inside a module container can be raised.

1 is a side sectional view of a solid oxide fuel cell device according to an embodiment of the present invention. It is an enlarged view about the heat exchange part of side sectional drawing of FIG. It is an enlarged view which shows the heat exchanger plate by one Embodiment of this invention. It is a three-plane figure which shows the heat exchanger plate by one Embodiment of this invention. They are the perspective view (a) which shows the flow of the fluid of the heat exchanger plate by one Embodiment of this invention, the enlarged view (b) of the convex part of a heat exchanger plate, and the enlarged view (c) of a recessed part. It is a top view which shows the flow of the fluid of the heat exchanger plate by one Embodiment of this invention. It is a figure which shows the conventional heat exchanger plate. 1 is a side sectional view of a solid oxide fuel cell device according to an embodiment of the present invention. It is an enlarged view about the heat exchange part of the side sectional view of FIG. It is a figure for demonstrating the flow of gas in FIG. 1 is an overall configuration diagram showing a solid oxide fuel cell apparatus according to an embodiment of the present invention. 1 is a front sectional view showing a fuel cell module of a solid oxide fuel cell device according to an embodiment of the present invention. 1 is a perspective view of a solid oxide fuel cell device according to an embodiment of the present invention with a heat insulating material and a housing removed from a fuel cell module. 1 is an enlarged vertical sectional view showing a part of an exhaust gas passage and an oxidant gas passage of a solid oxide fuel cell device according to an embodiment of the present invention. 1 is a partial cross-sectional view showing a fuel cell unit of a solid oxide fuel cell according to an embodiment of the present invention. 1 is a front sectional view showing a fuel cell module for explaining a gas flow in a fuel cell module of a solid oxide fuel cell device according to an embodiment of the present invention. FIG. 13 is a side cross-sectional view of the fuel cell module taken along line III-III of FIG. 12 for explaining a gas flow in the fuel cell module of the solid oxide fuel cell device according to the embodiment of the present invention.

(Embodiment 1)
In the present embodiment, the heat exchanging portion and the vicinity of the exhaust gas inlet in the solid oxide fuel cell device according to the present invention will be described with reference to FIGS. 1 and 2.

  FIG. 1 is a view showing a side surface of a solid oxide fuel cell device 500 in the present embodiment. A plurality of fuel cells 502 arranged upright on the fuel gas manifold 509 are accommodated inside the module container 503. An evaporator 506 is disposed above the module container 503, and the module container 503 and the evaporator 506 are covered with a heat insulating material 501. A heat insulating material 501 is also disposed between the module container 503 and the evaporator 506. A combustion unit 503 is provided above the plurality of fuel cells 502, and a reformer 504 is provided above the combustion unit 503. In FIG. 1, oxidant gas supply passages for supplying an oxidant gas supplied from the outside to the fuel cell 502 are formed on both side surfaces of the module container. A heat exchanging unit 507 is formed above the reformer 504 and on the top surface of the module container 503. The heat exchanging unit 507 is provided so as to spread horizontally with the top surface of the module container 503, and in the heat exchanging unit 507, an upper portion has an oxidant passage formed by the cover member and the top surface of the module container 503. The lower portion has an exhaust gas passage formed by a top surface of the module container 503 and a plate-like member installed below the top surface.

  The water supplied from the outside is heated inside the evaporator 506, and similarly supplied to the reformer 504 as a mixed gas mixed with the raw material gas supplied from the outside. Further, the raw material gas is reformed into the fuel gas inside the reformer 504 in a high temperature state, and the fuel gas is supplied into the fuel cell 502 through the fuel gas manifold 509. On the other hand, the oxidant gas supplied from the outside passes through the heat exchange unit 507 and is supplied from the oxidant gas supply passage 508 to the outer surface of the fuel cell 502. The fuel cell 502 to which fuel gas is supplied inside and oxidant gas is supplied to the outside generates power by a power generation reaction under a high temperature state of, for example, 600 ° C. or higher.

  On the other hand, the remaining fuel gas (off-gas) that is not used for power generation is discharged from the upper end of the fuel cell 502 and burned in the combustion unit 505 to generate exhaust gas. The exhaust gas rises inside the module container 503 while heating the bottom and side surfaces of the reformer 504. Thus, the reformer 504 can be heated and maintained at the reforming temperature necessary for reforming the raw material gas by heating with the exhaust gas. The exhaust gas rising to the upper part of the module container 503 while heating the reformer 504 is supplied to the heat exchange unit 507 from the exhaust gas inlets located at both upper ends of the module container 503 in a side view of the module container 503. Inside the heat exchanging unit 507, the oxidant gas supplied from the outside of the fuel cell module and the exhaust gas are heat-exchanged, and the oxidant gas heated by the recovered heat amount is transferred from the oxidant gas supply passage 508 to the fuel cell 502. On the other hand, the exhaust gas with reduced heat quantity passes through the inside of the evaporator 506 separated from the module container 503, and is recovered by heat generation for the generation of water vapor and preheating of the raw material gas, and then the solid oxide fuel cell device 500 It is discharged outside.

  FIG. 2 is an enlarged view of the upper left side of the module container 503 in a side view of the module container 503.

  That is, the heat exchanging section 507 shown in FIG. 1 includes the lower exhaust gas passage 550 through which the exhaust gas flows and the upper oxidant gas passage 551a through which the oxidant gas flows. The exhaust gas passage 550 is partitioned and formed with the top surface of the module container 503 as an upper surface and a plate-like member 511 disposed at a substantially equal distance below the top surface as a lower surface. On the other hand, the oxidant gas passage 551a is sectioned with the top surface of the module container 503 as the bottom surface and the cover member 510 disposed at approximately equal distances above the top surface as the top surface.

  In FIG. 2, the exhaust gas enters the heat exchanging portion from the exhaust gas inlet at the left end provided as a plane parallel to the side surface of the module container 503, flows in the horizontal direction substantially horizontally, and then is positioned at the approximate center of the module container 503. The exhaust gas is discharged to the evaporator through the exhaust gas discharge port 552 and the exhaust pipe. On the other hand, the oxidant gas supplied from the outside is supplied to the approximate center of the oxidant gas passage 551a in the heat exchange unit 507 in the top view of the module container via the oxidant gas introduction pipe (not shown). The oxidant gas in the oxidant gas passage 551a flows to the left substantially horizontally and moves to the oxidant gas passage 551b that continues downward at the end of the heat exchange unit 507. In this way, the exhaust gas supplied from the end to the exhaust gas passage 551a in the heat exchange unit 507 moves in the horizontal direction toward the center of the module container 503, while the oxidant gas passage in the center of the module container 503. Since the oxidant gas supplied to 551a moves toward the end of the module container 503, the exhaust gas and the oxidant gas horizontally flow in opposite directions (opposite flow). At this time, since the top surface 554 of the module container 503 functions as a heat exchange surface, the heat of the exhaust gas moves to the oxidant gas, whereby heat exchange between the exhaust gas and the oxidant gas is performed.

  The oxidant gas passage through which the oxidant gas flows may be partially formed on the side surface of the module container in addition to the top surface of the module container. That is, the cover member 510 for defining the oxidant gas passage 551a on the top surface 554 of the module container is further bent and extended to the side surface of the module container, so that the side surface of the module container and the cover member 510 are An oxidant gas passage 551b is formed therebetween.

  The exhaust gas is introduced into the exhaust gas passage 550 from the exhaust gas inlet 555 of the heat exchange unit 507. The exhaust gas inlets 555 are provided at both ends of the top surface 554 of the module container 503 and are formed on surfaces orthogonal to the top surface 554 of the module container 503. By arranging the exhaust gas inlets 555 at the upper ends of the module container 503 in this way, the heat of the hot exhaust gas rising in the module container 503 can be recovered as it is, and the exhaust gas outlet 552 of the heat exchange unit 503 is also collected. Is disposed in the central portion of the module container 503 as viewed from above, so that a sufficient heat exchange distance (area) with the oxidant gas can be secured, so that the heat exchange efficiency can be improved.

  However, in the heat exchanging unit 507 according to the present embodiment arranged on the top surface 554 of the module container 503, the exhaust gas passage in the heat exchanger 507 extends in the horizontal plane direction, so the lower combustion unit 505 in the module container 503 is provided. It is necessary to change the course of the exhaust gas rising from the exhaust gas so that it travels in the horizontal direction inside the heat exchange unit 507, but the exhaust gas is concentrated in the vicinity of the exhaust gas inlet 555 which is the inlet of the exhaust gas to the heat exchange unit 507. However, since convection occurs, there is a problem that the smooth entry of the exhaust gas into the heat exchange unit 507 is hindered.

  In view of this, an exhaust gas induction unit that guides the exhaust gas to the exhaust gas passage 550 is provided on the upstream side of the heat exchange unit 507 with respect to the exhaust gas flow and in the vicinity of the exhaust gas inlet 555. The exhaust gas guiding unit changes the flow direction of the rising exhaust gas in the horizontal direction. For example, a single convex structure for guiding the exhaust gas to the exhaust gas passage 550 is provided on the side surface of the module container 503 in the vicinity of the exhaust gas inlet 555. Alternatively, a plurality can be provided. Further, the corner corner wall of the module container 503 where the top surface 554 and the side surface 558 of the module container 503 are connected can be formed as a tapered surface that is inclined.

  As described above, by providing the exhaust gas guiding member that guides the exhaust gas to the exhaust gas passage 550 of the heat exchange unit 507 in the vicinity of the exhaust gas inlet 555, the heat exchange unit is caused by convection generated by the exhaust gas concentrated in the vicinity of the exhaust gas inlet 555. It is possible to suppress or prevent the entry of the exhaust gas to 507 from being hindered.

  As shown in FIG. 2, in the present embodiment, the exhaust gas guiding portion is a corner corner wall 553 of the module container 503 in which the top surface 554 of the module container 503 and the side surface 558 of the module container are connected to each other. The exhaust gas rising inside 503 is given a curvature so as to go to the exhaust gas inlet.

  In this way, by making the corner corner portion 553 of the module container 503 have a curvature, the direction of the rising exhaust gas is changed to a horizontal direction that is perpendicular to the direction, and the exhaust gas is guided to the exhaust gas inlet 553. can do. In particular, by making the corner corner portion 553 have an arcuate shape, it is possible to eliminate the stagnation of the exhaust gas in the vicinity of the exhaust gas inlet 555 and smoothly introduce the exhaust gas into the exhaust gas passage 550 of the heat exchange unit 507.

  In FIG. 2, the flow of exhaust gas is indicated by solid arrows, and the flow of oxidant gas is indicated by broken arrows. The exhaust gas rises while heating the reformer 504 and is distributed so as to concentrate toward the exhaust gas inlet 555. In FIG. 2, the reformer 504 is configured to have an opening in the central portion in order to improve the temperature rise performance by the exhaust gas, but the present invention is not limited to this, and the exhaust gas is heated by the exhaust gas and the exhaust gas is in the module container 503. If it is the structure which can go to the top | upper surface, the structure and shape of the reformer 504 can be designed appropriately.

  Although the exhaust gas concentrates in the vicinity of the exhaust gas inlet 555, the course is changed in the horizontal direction so as to be introduced into the exhaust gas passage 550 of the heat exchange unit 507 by the curvature surface of the corner corner portion 553 of the module container 503. For this reason, exhaust gas convection does not occur in the vicinity of the exhaust gas inlet 555, and the exhaust gas is smoothly introduced into the heat exchange unit 507.

  As described above, when the corner corner portion 553 of the module container 503 has a curved shape, the oxidant gas passage 551b extending in the direction orthogonal to the oxidant gas passage 551a extending in the horizontal direction at the same time is connected. Pressure loss can also be reduced at the bent portion. For this reason, it becomes possible to change smoothly the course of oxidant gas which flows inside, and efficient heat exchange with exhaust gas can be performed.

  The above-described shape that allows the corner corner portion 553 of the module container 503 to have a curvature is also advantageous in that it does not add a special member, and is a countermeasure for a problem that suppresses an increase in cost. .

  On the other hand, in FIG. 2, the oxidant gas passage extends in a bent manner from the top surface 554 to the side surface 558 of the module container 503 together with the oxidant gas passage 551 a provided on the module top surface 554. As a result, an oxidant gas passage 551b extending to a part of the side surface 558 of the module container 503 is provided. The curvature of the corner angle wall 557 of the cover member 510 formed by bending the oxidant gas passage 551a and the oxidant gas passage 551b is larger than the curvature of the corner angle wall 553. By setting the curvature of the corner corner wall 557 in the oxidant gas flow path to be large, it is possible to secure a large volume of the oxidant gas passage at the location. For this reason, it is possible to further reduce the increase in pressure loss at the corner corners of the oxidant gas passage.

(Embodiment 2)
In this embodiment, first, a heat transfer plate shown as an example of a heat transfer plate used in the present invention will be described while comparing the fluid diffusion mechanism with a conventional structure.

  In general, a heat transfer plate used for a heat exchanger increases the amount of heat exchange of a fluid passing through two thermally connected flow paths, and extends the flow path by meandering the flow path or functions as a flow path resistance. There have been devised measures such as increasing the heat exchange area and increasing the heat exchange time by installing members. For example, the conventional corrugated fin shown in FIG. 7 is obtained by folding a heat transfer plate in a bellows shape, and the folded flow path functions as a flow resistance against the fluid passing through the interior. To do. Further, since the fluid passing through the inside moves in contact with the upper surface, the lower surface, and the side surface (wall surface) of the folded heat transfer plate, heat exchange with other flow paths is promoted through the heat transfer plate.

  However, in the conventional heat transfer plate (fin), the fluid is almost straightly discharged through each of the plurality of divided flow paths. For this reason, since the fluid does not flow in the direction orthogonal to the flow, the temperature diffusivity in the orthogonal direction is low, and it is difficult to make the heat quantity in the entire flow path uniform.

  On the other hand, the heat transfer plate used as an example in the present embodiment has a plurality of convex portions 301 shifted on the surface of the heat transfer plate 300 as shown in FIG. For this reason, when the fluid is introduced from one end of the heat transfer plate 300, the fluid flowing on the upper surface of the heat transfer plate 300 always collides with the convex portion 301 in the initial flow direction, and the direction is forced to change. For this reason, since the fluid does not go straight through the heat transfer plate 300 and always collides with the convex portion 301, the convex portion 301 functions as a flow path resistance. Therefore, the flow velocity of the fluid on the heat transfer plate 300 decreases as a whole, and as a result, heat exchange is promoted.

  In the present specification, a high-temperature fluid and a low-temperature fluid that are heat exchange targets are collectively referred to as “fluid”. Here, the fluid is not limited to exhaust gas as a high-temperature fluid and oxidant gas as a low-temperature fluid, which will be described in detail below, and includes various gases or liquids that can be used in fuel cell devices and can be heat exchanged. .

  Furthermore, the heat transfer plate 300 used as an example in the present embodiment can be long diffused in a direction orthogonal to the direction in which the fluid flows into the heat transfer plate 300. FIG. 4 is a three-side view showing a heat transfer plate used as an example in the present embodiment. FIG. 4 (a) is a top view, FIG. 4 (b) is a front view (direction in which fluid flows), and FIG. Is shown. As shown in FIG. 4, a plurality of convex portions 301 are provided on the surface of the heat transfer plate 300, and a first region 302 a in which a plurality of convex portions 301 are arranged in a direction orthogonal to the direction in which the fluid flows, The second regions 302b where the convex portions 301 are not provided are provided alternately. For this reason, when the fluid whose direction of flow has been changed by the convex portion 301 enters the second region 302b, the convex portion 301 that is a collision target of the fluid is not provided, so that the fluid can travel straight. Spreads over a wide area without damage. For this reason, since the fluid can be diffused in a wide area, the heat can be made uniform.

  In the example shown in FIG. 6, the convex portions 301 are provided on both surfaces of the heat transfer plate 300, and the convex portions 301 indicated by dotted lines indicate the convex portions provided on the back surface (that is, the concave portions 303 viewed from the front surface). ing. In this case, a convex portion is provided on the back surface of the second region 302b where the convex portion 301 is not provided.

  Furthermore, the heat transfer plate 300 used as an example in the present embodiment can flow in three dimensions while allowing the fluid flowing through the heat transfer plate 300 to reach both the upper and lower surfaces of the heat transfer plate 300. The uniformity of the heat in the path can be improved and the heat exchange rate of the heat exchange part can be improved.

  As described above, in the conventional heat transfer plate 300 shown in FIG. 7, the flow path is partitioned into a plurality of walls by the wall surface of the heat transfer plate folded in a bellows shape, so that the fluid can only go straight through each partition. . Alternatively, even if a vent is provided in the wall surface to allow the passage between the partitioned flow paths, the flow of the fluid is largely blocked by the wall surface of the adjacent partition. It is scarce, and it does not lead to soaking of the whole flow path.

  On the other hand, the heat transfer plate used as an example in the present embodiment includes a vent hole on the upper surface of the heat transfer plate 300 that allows fluid to flow to the lower surface together with the convex portion 301. Therefore, the heat transfer plate 300 is provided with a plurality of air holes so that the heat transfer plate can flow between the upper surface and the lower surface of the heat transfer plate. The fluid that has collided with the portion 301 can flow not only to the upper surface of the heat transfer plate 300 but also to the lower surface. Accordingly, the fluid can be diffused over a wide area by using both surfaces of the heat transfer plate 300, so that the heat exchange efficiency can be improved.

  Here, as shown in FIG. 3, the heat transfer plate 300 according to the present invention forms a convex portion 301 and a vent hole 301 c formed on the heat transfer plate 300 as a pair cut and raised from the heat transfer plate 300. It is possible. That is, since the convex part 301 and the vent hole 301c can be formed in the same area | region, it can form in high density and can improve heat exchange performance by this. In addition, since the plurality of convex portions 301 and the air holes 301c can be formed by cutting and raising once, the manufacturing is very easy and the manufacturing cost can be reduced.

  Note that when the convex portion 301 and the concave portion 303 are formed on the heat transfer plate 300, both sides of the heat transfer plate 300 may be pressed and stamped by pressing with a press machine, or roller processing may be performed. May be performed. Further, the cut and raised may be formed by combining press working and roller working.

  Further, a heat transfer plate 300 used as an example in the present embodiment will be described with reference to FIGS. 4 and 5. As shown in FIG. 4C, both surfaces of the heat transfer plate 300 have a convex portion 301 cut and raised from the heat transfer plate 300 and a concave portion 303 generated on the back surface by the cut and raised, The back surface of the first region 302a corresponds to the second region 302b, and the back surface of the second region corresponds to the first region. That is, the heat transfer plate 300 according to the present invention can form the convex portions 301 and the concave portions 303 on both surfaces by cutting and raising by one press working. As a result, a heat transfer plate that can flow three-dimensionally and that has the same quality of heat exchange performance on both surfaces of the heat transfer plate can be manufactured at low cost.

  FIG. 5 shows an example of the fluid flow on the surface of the heat transfer plate 300. FIG. 5A is a perspective view of the heat transfer plate 300, FIG. 5B is an enlarged view of the convex portion 301, and FIG. 5C is an enlarged view of the concave portion 303. The arrows in the figure indicate the flow of fluid, the solid line arrows indicate an example of fluid flowing on the surface of the heat transfer plate 300, and the dotted line arrows indicate an example of fluid flowing on the back surface of the heat transfer plate 300. An example of the flow of fluid passing through the convex portion 301 will be described with reference to FIGS. 5 (a) and 5 (b). The fluid flowing into the convex portion 301 passes through the convex portion 301 in FIG. 5A and blows through the upper surface of the heat transfer plate 300 as it is, and passes through the vent hole 301c and passes through the lower surface of the heat transfer plate 300. Dispersed into the flow path (304b) that blows through, the flow path (304c) that refracts and collides with the leg portion 301a of the projection 301. The fluid that has passed through the convex portion 301 then diffuses by interfering with other convex portions and concave portions, and these fluids affect each other, thereby presenting a complex and wide-area diffusion as a whole.

  Furthermore, an example of the flow of the fluid flowing into the recess 303 will be shown with reference to FIGS. 5 (a) and 5 (c). The fluid that flows into the recess 303 flows straight through the recess 303 and flows to the other recess 303 (305a) and the recess 303 (the vent hole 301c on the lower surface of the heat transfer plate 300) and flows through the lower surface (305b). ), After passing through the concave portion 303, collides with the leg portion 301 a of the convex portion 301, refracts the flow path (305 c), flows into the concave portion 303, and the leg portion 301 a of the convex portion 301 corresponding to the concave portion 303 They are in contact with each other and dispersed in the flow path (305d) that refracts the lower surface of the heat transfer plate 300 and flows. Therefore, by passing through the recess 303, the fluid is three-dimensionally diffused and heat dispersibility is improved. In addition, although it showed as an example which simplified the flow of the fluid here, naturally the flow of the fluid is naturally complicated, In the heat transfer plate 300 concerning this invention, the fluid is the heat transfer plate 300. As long as it functions so as to diffuse three-dimensionally.

  Further, in the present invention, the convex portion 301 has a long side and a short side in a top view, and has a bridge shape having a girder portion 301b and a leg portion 301a. It is possible to integrally form a girder part 301b that contacts the flow path wall surface and transfers heat and a vent hole 301c that enables movement of fluid to the lower surface. Further, the shape can be formed by a simple manufacturing process at low cost by cutting and raising by one press working.

  Further, as shown in FIG. 6, the plurality of convex portions 301 are arranged such that the long side or the short side is inclined with respect to the direction in which the fluid flows onto the heat transfer plate 300 in a top view. Therefore, by disposing the convex part 301 on the rectangle having the long side and the short side in the top view obliquely in the flow direction, the flow of the fluid colliding with the convex part can be changed in the left-right direction. Fluid can be diffused over a wide area.

  In addition, as shown in FIGS. 4A and 6, one aspect of the configuration of the invention disclosed in this specification is that the plurality of convex portions 301 in the first region have the same direction and angle in a top view. In the first regions 302a adjacent to each other with the first region 302a interposed therebetween, the convex portions are disposed so as to be orthogonal to each other when viewed from above. That is, by arranging the convex portions 301 in the adjacent first regions 302a so as to be orthogonal to each other, the fluid whose direction of flow has changed further collides with the convex portions 301, so that the diffusion performance can be improved. it can.

  By configuring the heat transfer plate 300 as described above, the heat transfer plate 300 functions as a flow path resistance, and the residence time of the fluid passing through the heat exchanger is increased, thereby enabling heat exchange of a necessary amount of heat. Become. That is, by providing the heat transfer plate 300 in the solid oxide fuel cell device that uses exhaust heat, the heat exchange efficiency is maintained and improved with a simple structure, and the heat exchange unit that is easy to manufacture and has a low cost is provided. A solid oxide fuel cell device can be provided.

(Embodiment 3)
In this embodiment, as an example of the embodiment of the present invention using the heat transfer plate, FIGS. 8 to 10 are shown for the solid oxide fuel cell device using the heat transfer plate described in the second embodiment. It explains using.

  FIG. 8 is a diagram for explaining the solid oxide fuel cell device according to the present embodiment, which is different from FIG. 1 in that only a plurality of heat transfer plates 512 are used. The heat transfer plate 512 is disposed inside the exhaust gas passage and the oxidant gas passage. Since other configurations are the same as those in FIG. 1, the description thereof is omitted.

  9 and 10 are enlarged views of the upper left side of the module container 503 in a side view of the module container 503, and correspond to FIG. 2 in which the heat transfer plate 512 is not disposed. The exhaust gas passage 550 is provided with a heat transfer plate 512a, and the oxidant gas passage 551a provided on the top surface of the module container 503 facing the exhaust gas passage 550 is provided with a heat transfer plate 512b on the side surface of the module container. A heat transfer plate 512c is provided in the oxidant gas passage 551b.

  The heat transfer plate 512 facilitates heat exchange between the exhaust gas flowing through the module container 503 and the wall surfaces of the exhaust gas passage 550 and the oxidant gas passages 551a and 551b, and the oxidant gas. To do. As described in the second embodiment, the heat transfer plate 512 uses a plate member having a plurality of convex portions shifted on the front and back surfaces.

  Such a substantially flat heat transfer plate 512 can be arranged in accordance with the planar extent of the exhaust gas passage 550 and the oxidant gas passages 551a and 551b. As described above, since the heat transfer plate 512 has a plurality of convex portions arranged on the front and back surfaces of the plate-like member, the plate-like member is positioned at the approximate center of the distance between the passages with the convex portion as a support. It is arranged. Thus, by arrange | positioning the heat exchanger plate 512 in each channel | path, the inside of each channel | path can be divided into upper and lower (or right and left) space. In addition, since the heat transfer plate 512 used in the present embodiment has a vent hole formed in accordance with the position where the convex portion is formed, the space divided by the heat transfer plate 512 flows through the inside of the passage. Fluid can go back and forth.

  Here, the exhaust gas flowing through the exhaust gas passage and the oxidant gas flowing through the oxidant gas passage exchange heat with the top surface 554 of the module container 503 that is a common surface constituting a part of each passage. I do. Therefore, in order to increase the heat exchange efficiency, the exhaust gas is made to flow to the upper layer 560a side of the lower layer 560b in the exhaust gas passage 550 divided into two by the heat transfer plate 512a, and the oxidant gas is divided into two by the heat transfer plate 512b. The oxidant gas passage 551a preferably flows to the lower layer 561b rather than the upper layer 561a. Heat exchange efficiency can be improved by flowing exhaust gas and oxidant gas in contact with the top surface of the module container 503 which is a heat exchange surface.

  Here, the oxidant gas passage includes an oxidant gas passage 551 a provided on the top surface 554 of the module container 503 and an oxidant gas passage 551 b provided on the side surface 558 of the module container 503. Each oxidant gas passage is divided into two by heat transfer plates 512b and 512c. At this time, the corner member 557 of the oxidant gas passage formed by bending the cover member 510 at the corner portion of the module container 503 preferably has an R shape. With this configuration, it is possible to suppress an increase in pressure loss due to the oxidant gas at the corner corner portion 557 by maximizing the volume of the oxidant gas passage and to be positioned on the top surface 554 and the side surface 558 of the module container 503. In each of the oxidant gas passages, a heat transfer plate can be disposed in contact with each other at a corner corner portion 557. By arranging the two heat transfer plates in contact with each other at the corner corner portion 557 of the oxidant gas passage so as to be orthogonal to each other, in the continuous oxidant gas passage extending from the oxidant gas passage 551a to the oxidant gas passage 551b, the oxidant The upper layer 561a and the lower layer 561b of the gas passage can be reliably separated. Thus, since the upper and lower layers of the oxidant gas passage are clearly separated, the oxidant gas can flow mainly to the lower layer in order to improve the heat exchange efficiency.

  Further, in the oxidant gas passage, it is preferable that the convex portion of the heat transfer plates 512b and 512c is not arranged in the lower layer 561b portion of the corner corner wall 557 where the cover member 557 is bent. In the corner angle wall 557 of the oxidant gas passage formed by bending the cover member, the convex portions of the heat transfer plates 512b and 512c divided into two layers are arranged so as not to be positioned, so that the lower layer compared to the upper layer 561a. Since the pressure loss of the oxidant gas flowing through 561b is small, the oxidant gas can flow mainly in the lower layer at the corner corner portion 557. For this reason, oxidant gas can be flowed so that the top surface 554 and side 558 of module container 503 may be touched, and heat exchange efficiency can be raised.

  As shown in FIG. 10, a heat transfer plate 512 a that divides the exhaust gas passage 550 into two-layer passages (upper layer 560 a and lower layer 560 b) parallel to the top surface 554 of the module container 503 is disposed in the exhaust gas passage 550. The heat transfer plate 512a is arranged inside the exhaust gas inlet 555 inside the heat exchange unit 507.

  If the heat transfer plate 512a is disposed in the vicinity of the exhaust gas inlet 555, the heat transfer plate 512a functions as an obstacle that prevents gas flow, and pressure loss increases at the corner corner portion 553 into which the exhaust gas flows. . Therefore, by increasing the heat transfer plate 512a with respect to the exhaust gas inlet 555, an increase in pressure loss at the corner corner portion 553 can be mitigated. If the offset distance between the heat transfer plate 512a and the exhaust gas inlet 555 is too short, the pressure loss near the exhaust gas inlet 555 increases, whereas if it is too long, the upper layer that separates the exhaust gas by the heat transfer plate 512a. Since the area for improving the heat exchange efficiency is reduced by concentrating on 560a, it is desirable to appropriately set an appropriate offset distance in accordance with the design of the module container 503, the exhaust gas passage 550, and the like.

  Further, the heat transfer plate 512a includes a main surface that divides the exhaust gas passage 550 into two-layer passages parallel to the top surface 554 of the module container 503, and one of the two-layer passages (upper layer 560a and lower layer 560b). It has a pair of convex portions and a plurality of vents arranged on the main surface to allow the exhaust gas to flow to the other layer and to conduct heat with the top surface 554 of the module container 503, and is divided into two layers. In the exhaust gas passage 550, it is preferable that the convex portion of the heat transfer plate 512a is not disposed in the vicinity of the exhaust gas inlet 555 of the upper layer 560a.

  As described above, in the corner corner wall 553, the exhaust gas is mainly caused to flow to the upper layer 560 a in the corner corner wall by disposing the convex portion on the main surface of the heat transfer plate 512 a partitioned into two layers. be able to. For this reason, it is possible to promote heat exchange with the oxidant gas by flowing the exhaust gas so as to be in contact with the wall surface of the module container 503, and to improve heat exchange efficiency.

  Embodiments of a solid oxide fuel cell device according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 11 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. 11, 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 (see FIG. 15) connected in series. In this example, the fuel cell assembly 12 has 128 fuel cell units 16.

  A combustion section 18 is formed above the power generation chamber 10 of the module container 8 of the fuel cell module 2. In this combustion section 18, the remaining fuel gas that has not been used for power generation reaction (has not contributed to power generation) and The remaining oxidant gas is 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 section 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 for cutting off the oxidant gas supplied from the oxidant gas supply source 40, a reforming oxidant gas flow rate adjusting unit 44 for adjusting the flow rate of the oxidant gas, and an oxidant. A gas flow rate adjusting unit 45 (such as an “oxidant gas blower” driven by a motor), a first heater 46 for heating the reforming oxidant gas supplied to the reformer 120, and an oxidant supplied to the power generation chamber And a second heater 48 for heating the agent gas. 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 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 oxidant gas 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 a water supply source 24, and the tap water is heated by the heat of exhaust gas to be 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. FIG. 12 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. 13 is an exploded perspective view of a module container and an oxidant gas passage cover (cover member). It is.

  As shown in FIG. 12, the fuel cell module 2 includes a fuel cell assembly 12 and a reformer 120 provided inside a module container 8 covered with a heat insulating material 7, and outside the module container 8. In addition, an evaporator 140 provided in the heat insulating material 7 is provided.

  First, as shown in FIG. 13, the module container 8 includes a substantially rectangular top plate 8a, a 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. 12). It consists of a cylindrical body and closed side plates 8d and 8e that close two opposite openings at both ends in the longitudinal direction of the cylindrical body and connect the sides extending in the width direction of the top plate 8a and the bottom plate 8c.

  In the module container 8, the top plate 8 a and the side plate 8 b are covered with an oxidant gas passage cover (also referred to as a cover member) 160. The oxidant gas passage cover 160 has a top plate 160a and a pair of side plates 160b facing each other. An opening 167 for allowing the exhaust pipe 171 to pass therethrough is provided at a substantially central portion of the top plate 160a. The top plate 160a and the top plate 8a of the oxidant gas passage cover 160a and the side plate 160b and the side plate 8b are separated by a predetermined distance. Thereby, between the outer side 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 oxidant gas passage cover 160. The oxidant gas passages 161a and 161b as the oxidant gas supply passages are formed along the outer surfaces of the top plate 160a and the side plates 160b.

  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. 13). The oxidant gas is supplied from an oxidant gas introduction pipe 74 provided at a substantially central portion on the closed side plate 8e side of the module container 8 in the top plate 160a of the oxidant gas passage cover 160 through the flow direction adjustment unit 164. It is supplied into the oxidant gas passage 161a (see FIGS. 12 and 13). Then, the oxidant gas is injected into the power generation chamber 10 through the oxidant gas passages 161a and 161b from the outlet 8f toward the fuel cell assembly 12 (see FIG. 13).

  Further, inside the oxidant gas passages 161a and 161b, heat exchange promotion that promotes heat exchange between the exhaust gas in the exhaust gas passage 172 and the exhaust gas passage 173 and the oxidant gas in the oxidant gas passages 161a and 161b. Heat transfer plates 162 and 163 as members are provided (see FIG. 17). The heat transfer plate 162 is 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 oxidant gas passage cover 160. That is, the heat transfer plate 162 is provided in a portion corresponding to an exhaust gas passage 172 described later in the oxidant gas passage 161a. Further, the heat transfer plate 163 is located between the side plate 8b of the module container 8 and the side plate 160b of the oxidant gas passage cover 160 and in a position above the fuel cell unit 16 in the longitudinal direction and the vertical direction. It is provided to extend. That is, the heat transfer plate 163 is provided in a portion corresponding to an exhaust gas passage 177 and an exhaust gas concentration portion 176 described later in the oxidant gas passage 161b.

  The oxidant gas flowing through the oxidant gas passages 161a and 161b is heated between the exhaust gas passing through the module container 8 inside the heat transfer plates 162 and 163, particularly when passing through the heat transfer plates 162 and 163. It will be exchanged and heated. In particular, the portion where the heat transfer plate 162 is provided in the exhaust gas flowing through the exhaust gas passage 173 configured as a narrow passage and the oxidant gas passage 161a functions as a heat exchange portion with high heat exchange efficiency. For this reason, the part in which the heat exchanger plate 162 was provided functions as a main heat exchange part, and the part in which the heat exchanger plate 163 was provided also has a secondary heat exchange function.

  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 portion 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. 12 and 17).

  Specifically, the evaporator 140 supplies fuel and raw fuel gas (which may include reforming oxidant gas) to one side end side in the longitudinal direction (left-right direction in FIG. 12). The pipe 63 and an exhaust gas discharge pipe 82 for discharging exhaust gas are connected, and the upper end 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 oxidant gas passage cover 160, and is connected to the exhaust gas discharge port 111 formed on the top plate 8 a of the module container 8. Yes. The exhaust gas discharge port 111 is an opening through which the exhaust gas generated in the combustion unit 18 in the module container 8 is discharged 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.

  In addition, as shown in FIGS. 12 and 17, the evaporator 140 has a substantially rectangular evaporator case 141 in a 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 supply is supplied in the upper layer portion. An evaporation unit 140B that evaporates water supplied from the 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. ing.

  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, so that water vapor is generated. 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.

  Furthermore, as shown in FIG. 12, 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 so as to extend in the horizontal direction along the longitudinal direction of the module container 8 above the combustion unit 18, and the gas insulating layer 135 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. 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 gas discharge port 111 formed in the top plate 8a in a top view, and preferably, the exhaust gas discharge 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, and the hydrogen desulfurizer hydrogen extraction pipe 65 extending to the desulfurizer 36 is connected to the upper case 121. Therefore, the reformer 120 receives the mixed gas (that is, the raw fuel gas mixed with water vapor (which may include the oxidizing gas for reforming)) from the mixed gas supply pipe 112 and modifies the mixed gas therein. The reformed gas (i.e., fuel gas) is discharged from the fuel gas supply pipe 64 and the hydrogen desulfurizer hydrogen extraction pipe 65.

  The reformer 120 is divided into three spaces by two partition plates 123a and 123b so that the reformer 120 receives a mixed gas from the mixed gas supply pipe 112 into 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. 12). 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.
In the gas discharge unit 120C, the fuel gas is discharged to the fuel gas supply pipe 64 and the hydrogen extraction pipe 65 for the hydrodesulfurizer.

  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. It enters into a manifold 66 formed below the base plate, and further extends horizontally in the manifold 66 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 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 manifold 66, and the fuel gas in the manifold 66 is supplied into the fuel cell unit 16. The An ignition device 83 for starting combustion of fuel gas and oxidant gas is provided in the combustion unit 18.

  The gas heat insulating layer 135 is disposed so as to extend in the horizontal direction along the longitudinal direction of the module container 8 between the reformer 120 and the top plate 8a. The gas heat insulating layer 135 includes a lower surface member 131 and an upper surface member 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 (see FIG. 12). The upper surface member 132 is bent at both ends in the width direction downward and connected to the lower surface member 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 gas heat insulating layer 135 and the reformer 120 to the top plate 8a. Yes.

  As shown in FIG. 17, the lower surface member 131 is formed with a convex step portion 131 a in which the center portion in the width direction protrudes downward. On the other hand, similarly to the lower surface member 131, the upper surface member 132 is formed with a concave portion 132 a 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 in the recess 132a in the module container 8 in the horizontal direction, then bends downward near the closed side plate 8e, penetrates the upper surface member 132 and the lower surface member 131, and is reformed. Connected to the container 120.

  The gas heat insulating layer 135 is formed by a gas reservoir that is an internal space functioning as a heat insulating layer by the upper surface member 132, the lower surface member 131, and the connecting plates 133 and 134. This gas insulation layer 135 is in fluid communication with the combustion section 18. That is, the upper surface member 132, the lower surface member 131, and the connection plates 133 and 134 are connected so as to form a predetermined gap, and are not airtightly connected. The gas heat insulation layer 135 can flow exhaust gas from the combustion section 18 during operation, or can flow oxidant gas from the outside during stoppage. Gas movement is slow.

  The upper surface member 132 that forms the top surface of the gas heat insulating layer 135 is arranged at a predetermined vertical distance from the top plate 8a of the module container, and between the upper surface of the upper surface member 132 and the top plate 8a, An exhaust gas passage 172 extending in the horizontal direction along the longitudinal direction and the width direction is formed. The exhaust gas passage 172 is arranged in parallel with the oxidant gas passage 161a with the top plate 8a of the module container 8 interposed therebetween, and the exhaust gas passage 172 has the same heat transfer plate as the heat transfer plate 162 in the oxidant gas passage 161a. A hot plate 175 is disposed. The heat transfer plate 175 is provided at substantially the same location as the heat transfer plate 162 in a top view, and is opposed in the vertical direction with the top plate 8a interposed therebetween. The upper surface member 132 of the gas heat insulating layer 135 is disposed at a predetermined horizontal distance from the side surface of the upper surface member 132 and the side plate 8b, and between the side surface of the upper surface member 132 and the side plate 8b in the longitudinal direction and the upper and lower sides. An exhaust gas passage 177 extending in the direction is formed. The exhaust gas channel 177 communicates with the exhaust gas channel 172 in the upper part.

  Of the oxidant gas passages 161a and 161b, the exhaust gas passage 172, and the exhaust gas passage 177, efficient heat exchange is performed between the oxidant gas flowing through the oxidant gas passage 161a and the exhaust gas flowing through the exhaust gas passage 172. The oxidant gas is heated by the heat of the exhaust gas. In addition, heat exchange is performed secondarily between the exhaust gas flowing through the oxidant gas passage 161b and the exhaust gas flowing through the exhaust gas flow dew 177, and the temperature of the oxidant gas can also be increased by the heat of the exhaust gas at the relevant location.

  The reformer 120 is disposed at a predetermined horizontal distance from the side plate 8b of the module container 8, and the exhaust gas that allows the exhaust gas to pass from below to above is disposed between the reformer 120 and the side plate 8b. A flow path 173 is formed.

  Further, the lower surface member 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 surface member 131 and the upper case 121 and between the reformer 120. The through hole 120b forms an exhaust gas flow path 174 through which the exhaust gas that has passed through the through hole 120b from the bottom to the top passes. The exhaust gas flow path 174 joins the exhaust gas flow path 173 above the reformer 120 and in the vicinity of the side plate 8b to form an exhaust gas concentration portion 176 where exhaust gas concentrates.

  FIG. 14 is an enlarged vertical sectional view showing the exhaust gas passage 172 and the portion of the oxidant gas passage 161a corresponding thereto. As shown in FIG. 14, the heat transfer plate 175 is disposed between the upper surface member 132 and the top plate 8 a of the module container 8. The heat transfer plate 175 is in contact with the top plate 8b on the upper surface of the convex portion 204, but is in contact with the upper surface of the upper surface member 132 through a protrusion 205 provided on the lower surface of the convex portion protruding downward. Yes.

  The protrusion part 205 is formed so that a contact area becomes smaller than the top-plate part 204b, for example, can be formed by protruding a part of convex part 204 outward. Moreover, the protrusion part 205 can also be made into a member different from the heat exchanger plate with favorable heat conductivity. In this case, it is preferable to form with a material having lower thermal conductivity than the heat transfer plate.

  The protruding portion 205 is not provided on the lower surface of all the convex portions 204 on the upper surface side of the upper surface member 132, but is provided on at least one of the convex portions 204 protruding downward. For this reason, among the convex portions 204 protruding downward, most of the convex portions 204 do not come into contact with the upper surface of the upper surface member 132, and only one or a few of the convex portions 204 are interposed via the protrusions 205. It is in contact with the top surface.

  Thus, although the heat transfer plate 175 is in contact with the top plate 8a via the convex portion 204, the contact area is small with respect to the upper surface of the upper surface member 132, and preferably has thermal conductivity. Contact is made through the low protrusion 205. For this reason, the heat transfer plate 175 can increase the amount of heat transferred to the oxidant gas passage 161a as compared with the upper surface member 132 that defines the gas heat insulating layer 135. Thereby, it is possible to improve the heat exchange efficiency between the exhaust gas in the exhaust gas channel 172 and the oxidant gas in the oxidant gas passage 161a.

  The heat transfer plate 162 is disposed between the top plate 8 a of the module container 8 and the top plate 160 a of the oxidant gas passage cover 160. Similar to the heat transfer plate 175, the heat transfer plate 162 is in contact with the top plate 8a of the module container on the lower surface of the convex portion 202, but the top plate 160a of the oxidant gas passage cover 160 is not in the convex portion 202. Contact is made via a protrusion 203 provided on the upper surface.

  The protrusion 203 is formed to have a smaller contact area than the upper surface of the protrusion 202, and the protrusion 203 can be a separate member from the heat transfer plate with good thermal conductivity. In this case, it is preferable to form with a material having lower thermal conductivity than the heat transfer plate.

  Further, the protrusions 203 are not provided on the upper surfaces of all the protrusions 202 on the top plate 160 a side of the oxidant gas passage cover 160, and only one or a few protrusions 202 are disposed on the side plate via the protrusions 203. It is in contact with 160b.

  For this reason, it becomes possible to suppress heat dissipation (heat loss) from the heat transfer plate 162 to the external heat insulating material 7 through the top plate 160a, and oxidation of the exhaust gas in the exhaust gas passage 172 and the oxidant gas passage 161a. The heat exchange efficiency with the agent gas can be improved. The same applies to the heat transfer plate 163.

  Thus, by arranging the heat transfer plates in the oxidant gas passage 161a and the exhaust gas passage 172, the respective passages can be divided into upper and lower spaces. Here, since the heat exchange surface where the oxidant gas and the exhaust gas exchange heat is the top plate 160a, the oxidant gas in the oxidant gas passage 161a partitioned into upper and lower layers by the heat transfer plate lowers the heat exchange surface. In the heat exchange section, the oxidant gas is mainly flowed to the lower layer and the exhaust gas is mainly flowed to the upper layer having the heat exchange surface as the upper surface of the exhaust gas passage 172 divided into upper and lower layers by the heat transfer plate. Heat exchange efficiency can be improved.

  Next, the fuel cell unit 16 will be described with reference to FIG. FIG. 15 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. 15, 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 the oxidant gas 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. For this reason, a predetermined pressure loss occurs in the flow of the fuel gas flowing from the manifold 66 (see FIG. 12) into the fuel gas passage 88 through the fuel gas passage narrow tube 98 of the lower inner electrode terminal 86. To do. 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 section 18 (see FIG. 12) 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 is, 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 device according to one embodiment of the present invention will be described with reference to FIG. FIG. 16 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. FIG. 16 is a diagram in which an arrow indicating a gas flow is newly added in FIG. 12, and shows a state in which the heat insulating material 7 is removed for convenience of explanation. In the figure, solid arrows indicate the flow of fuel gas, broken arrows indicate the flow of oxidant gas, and alternate long and short dash arrows indicate the flow of exhaust gas.

  As shown in FIG. 16, 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 evaporator 140B is heated by the exhaust gas flowing through the exhaust passage 140A provided in the lower layer of the evaporator 140, and becomes 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 exhaust gas passage 172 in order, the mixed gas in the mixed gas supply pipe 112 is further heated by the exhaust gas flowing through these passages.

  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 branches from the gas discharge part 120 </ b> C into the fuel gas supply pipe 64 and the hydrodesulfurizer hydrogen extraction pipe 65. The fuel gas that has flowed into the fuel gas supply pipe 64 is supplied into the manifold 66 from the fuel supply hole 64 b provided in the horizontal portion 64 a of the fuel gas supply pipe 64, and from the manifold 66 into each fuel cell unit 16. Supplied.

  Also, as shown in FIG. 16, the oxidant gas is supplied from the oxidant gas introduction pipe 74 to the oxidant gas passage 161a. When the oxidant gas passes through the heat transfer plate 162 in the oxidant gas passages 161a and 161b, the oxidant gas passes through the exhaust gas passing through the exhaust passage 172 formed in the module container 8 below the heat transfer plate 162. However, efficient heat exchange is performed, and heating is performed.

  Thereafter, the oxidant gas is injected into the power generation chamber 10 from the plurality of outlets 8f provided at the lower portion of the side plate 8b 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 oxidant gas and the exhaust gas is suppressed at this portion. Therefore, in the side part of the fuel cell assembly 12, it is difficult for the oxidant gas in the oxidant gas passage 161b to have temperature unevenness in the vertical direction.

  Further, the fuel gas that has not been used for power generation in the power generation chamber 10 is burned in the combustion section 18 to become exhaust gas (combustion gas), and rises in the module container 8. Specifically, the exhaust gas flow path 173 that flows between the outer surface of the reformer 120 and the side plate 8 b of the module container 8, and the reformer 120 and the gas heat insulation layer 135 from the through hole 120 b of the reformer 120. It branches into an exhaust gas flow path 174 that flows between them. At this time, the exhaust gas passing through the exhaust gas flow path 174 is divided into two in the width direction by the convex step portion 131a disposed above the through hole 120b of the reformer 120, and does not stay below the gas heat insulating layer 135. It is guided toward the flow path 173 and merges with the exhaust gas flowing through the exhaust gas flow path 173 at the exhaust gas concentration part 176.

  Thereafter, the exhaust gas flows from the exhaust gas concentration part 176 to the exhaust gas flow path 177. The exhaust gas that has passed through the exhaust gas passage 177 flows in the horizontal direction in the exhaust gas passage 172, and flows out from the exhaust gas discharge port 111 formed at the center of the top plate 8 a of the module container 8.

  Here, when the exhaust gas flows through the exhaust gas passage 172, the oxidant is passed through the heat transfer plate 175 provided in the exhaust gas passage 172 and the heat transfer plate 162 provided in the oxidant gas passage 161a. An efficient heat exchange is performed between the gas and the exhaust gas. In this way, the temperature of the oxidant gas is raised by the heat of the exhaust gas.

  The exhaust gas flowing out from the exhaust gas discharge 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.

  According to the solid oxide fuel cell device 1 of the present embodiment, the following effects are exhibited. That is, in the present embodiment, a gas heat insulating layer 135 is provided between the top plate 8a of the module container 8 and the reformer 120, and the periphery is defined by a lower surface member 131 and an upper surface member 132 made of metal. An exhaust gas passage 172 and an exhaust gas passage 177 are formed between the gas heat insulating layer 135 and the top plate 8 a and the side plate 8 b of the module container 8. Thereby, heat is transferred from the high-temperature exhaust gas in the exhaust gas flow path 174 (that is, upstream) that has passed through the through-hole 120b of the reformer 120 to the low-temperature exhaust gas in the exhaust gas passage 172 (that is, downstream). It is possible to suppress the movement, and high-temperature exhaust gas flows from the exhaust gas concentration part 176 into the exhaust gas passage 177 and the exhaust gas passage 172. For this reason, heat exchange performance is improved and sufficient heat exchange can be performed between the exhaust gas and the oxidant gas even at a short heat exchange distance.

  Further, by providing the heat transfer plate 162 in the exhaust gas passage 172, heat exchange between the exhaust gas in the exhaust gas passage 172 and the oxidant gas in the oxidant gas passage 161a can be performed at a short distance.

  Here, in the vicinity of the exhaust gas inlet to the exhaust gas passage 172 provided between the gas heat insulation layer 135 and the top plate 8a of the module container 8 (exhaust gas channel 177 in FIG. 17), the exhaust gas rising from the combustion unit 18 is exhausted. There was a risk that the concentration of exhaust gas would be hindered. For this reason, in the comparative example, as indicated by an arrow C in FIG. 17, exhaust heat is dissipated from the exhaust gas staying in the exhaust gas flow path 177 to the gas heat insulating layer 135, and the temperature of the exhaust gas is reduced. There is a risk that the efficiency of heat exchange between the oxidant gas and the oxidant gas may be reduced. In view of this, the corner square wall where the top plate 8a and the side plate 8b of the module container 8 are connected to each other has a curved shape so that the rising exhaust gas is smoothly changed to a horizontal path so that the exhaust gas passage 172 can be smoothly formed. It was possible to guide to.

  Furthermore, a heat transfer plate that divides the passage into two upper and lower layers horizontally with respect to the gas traveling direction is disposed inside the exhaust gas passage 172 and the oxidant gas passages 161a and 161b. By disposing the part away from the corner corner wall and offsetting the heat transfer plate from the exhaust gas inlet, the exhaust gas and oxidant gas can flow through the layer that is in direct contact with the heat exchange surface to increase heat exchange efficiency. Can do.

  Thus, according to the present embodiment, the heat exchange between the exhaust gas and the oxidant gas can be efficiently performed by the heat exchange part formed near the top surface of the module container while reducing the size of the fuel cell device. Can be done.

  The solid oxide fuel cell device according to the present invention is widely useful in a solid oxide fuel cell device having a heat exchange part on the top surface of the module container.

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 unit 24 Water supply source 26 Pure water tank 28 Water flow rate adjustment unit 30 Fuel supply source 32 Gas shutoff valve 36 Desulfurizer 38 Fuel flow rate adjustment unit 39 Valve 40 Oxidant gas supply source 42 Electromagnetic valve 44 Reformation Oxidant gas flow rate adjustment unit 45 Power generation oxidant gas flow rate adjustment unit 46 First heater 48 Second heater 50 Hot water production device 52 Control box 54 Inverter 63 Fuel supply pipe 64 Fuel gas supply pipe 64a Horizontal portion 64b Fuel supply hole 65 Hydrogen extraction pipe 66 for hydrodesulfurizer Manifold 68 Lower support plate 74 Acid Agent gas introduction pipe 82 Exhaust gas discharge pipe 83 Ignition device 84 Fuel cell 86 Inner electrode terminal 88 Fuel gas channel 90 Inner electrode layer 92 Outer electrode layer 94 Electrolyte layer 96 Sealing material 98 Fuel gas channel narrow tube 111 Exhaust gas outlet 112 Mixing Gas supply pipe 120 Reformer 120A Mixed gas receiving portion 120B Reforming portion 120C Gas discharge portion 120a Mixed gas supply port 120b Through hole 121 Upper case 122 Lower case 123a Partition plate 123b Partition plate 131 Lower surface member 131a Convex stepped portion 132 Upper surface member 132a Recess 133 Connection plate 134 Connection plate 135 Gas heat insulation layer (gas reservoir)
140 Evaporator 140A Exhaust passage part 140B Evaporation part 140C Mixer part 141 Evaporator case 142 Upper case 143 Lower case 144 Intermediate plate 144a Opening 160 Oxidant gas passage cover 160a Top plate 160b Side plate 161a Oxidant gas passage 161b Oxidant gas passage 161b 162 Heat transfer plate 163 Heat transfer plate 164 Flow path direction adjustment portion 167 Opening portion 171 Exhaust pipe 172 Exhaust gas passage 173 Exhaust gas flow channel 174 Exhaust gas flow channel 175 Heat transfer plate 176 Exhaust gas concentration portion 177 Exhaust gas flow channel 202 Convex portion 203 Protrusion portion 204 Convex part 205 Protrusion part 300 Heat transfer plate 301 Convex part 301a Leg part 301b Girder part 301c Vent hole 302a First region 302b Second region 303 Concave 500 Solid oxide fuel cell device 501 Insulating material 502 Fuel cell 503 Module Container 504 Reformer 505 Fuel Baking part 506 Evaporator 507 Heat exchange part 508 Oxidant gas supply passage 509 Fuel gas manifold 510 Cover member 511 Plate member 512 Heat transfer plate 512a Heat transfer plate 512b Heat transfer plate 512c Heat transfer plate 550 Exhaust gas passage 551a Oxidant gas passage 551b Oxidant gas passage 552 Exhaust gas outlet 553 Corner corner wall, exhaust gas induction section 554 Top surface, heat exchange surface 555 Exhaust gas inlet 556 Mixed gas supply pipe 557 Corner corner wall 558 Side surface 560a Upper layer 560b Lower layer 561a Upper layer 561b Lower layer

Claims (7)

In a solid oxide fuel cell device using a plurality of fuel cells that generate power by reaction of fuel gas and oxidant gas,
A rectangular parallelepiped module container accommodating the plurality of fuel cells;
A heat insulating material covering the periphery of the module container;
A fuel gas supply passage for supplying fuel gas to the plurality of fuel cells, and
A reformer disposed in the module container and reforming raw fuel gas into fuel gas by steam and supplying the fuel gas to the fuel gas supply passage;
A combustion section that burns fuel gas remaining in power generation of the plurality of fuel cells and heats the reformer provided above by combustion heat;
An evaporator which is disposed outside the module container and in the heat insulating material, and supplies a mixed gas of water vapor and raw fuel gas generated by evaporating the supplied water to the reformer;
A heat exchanging unit which is provided from one end to the other end of the top surface of the module container, and exchanges heat between the exhaust gas generated by the combustion of the combustion unit and the oxidant gas supplied from the outside of the module container;
Exhaust gas discharged from the heat exchange part to the outside of the module container, provided in the center of the top surface of the module container,
An oxidant gas supply passage for supplying the oxidant gas discharged from the heat exchange unit to the plurality of fuel cells, and
The heat exchanging unit includes exhaust gas flowing through an exhaust gas passage formed by a top surface of the module container and a lower surface made of a plate-like member provided inside the module container, a top surface of the module container, and the module container An oxidant gas flowing through an oxidant gas passage formed by an upper surface formed of a cover member provided outside the heat exchanger, and configured to exchange heat through the top surface of the module container,
The exhaust gas inlet of the heat exchange part is located on both of the pair of end parts on the top surface of the module container, and is located on a surface orthogonal to the top surface of the module container,
A solid oxide, characterized in that an exhaust gas guiding part for guiding the exhaust gas to the exhaust gas passage is provided in the vicinity of the exhaust gas introduction port on the upstream side of the heat exchange part with respect to the flow of the exhaust gas. Fuel cell device.   The exhaust gas guiding portion is a corner corner wall of the module container where a top surface of the module container and a side surface of the module container are connected to each other, and the exhaust gas rising inside the module container is directed to the exhaust gas inlet. 2. The solid oxide fuel cell device according to claim 1, wherein the solid oxide fuel cell device has a curvature as described above. The oxidant gas passage extends to a part of the side surface of the module container by bending and extending the cover member from the top surface to the side surface of the module container.
3. The solid oxide fuel cell device according to claim 2, wherein a curvature of the corner corner wall is smaller than a curvature of the corner corner wall of the cover member formed by the bending. The oxidant gas passage extends to a part of the side surface of the module container by bending and extending the cover member from the top surface to the side surface of the module container.
The square wall of the cover member formed by bending is R-shaped,
In each of the oxidant gas passages formed between the cover member and the top surface of the module container and between the cover member and a side surface of the module container, the oxidant gas passages are respectively provided in the oxidant gas passages. 3. The solid oxide form according to claim 2, wherein heat transfer plates that are divided into two-layer passages parallel to the wall surface of the module container are disposed, and these heat transfer plates are in contact with each other at the square wall. Fuel cell device. The heat transfer plate includes a main surface that divides the oxidant gas passage into two-layer passages parallel to the wall surface of the module container, and oxidant gas from one layer to the other of the two-layer passages. In order to allow the flow and heat conduction with the top surface of the module container, a plurality of a plurality of convex portions and a vent hole arranged on the main surface,
The convex portion of the heat transfer plate is not disposed in a lower layer portion of the corner wall of the cover member in the oxidant gas passage divided into the two layers. The solid oxide fuel cell device described.   A heat transfer plate that divides the exhaust gas passage into two-layer passages parallel to the top surface of the module container is disposed in the exhaust gas passage, and the heat transfer plate is disposed in the exhaust gas inlet in the heat exchange section. The solid oxide fuel cell device according to claim 2, wherein the solid oxide fuel cell device is disposed on the inner side. The heat transfer plate enables the exhaust gas to flow from one layer to the other of the two layers of the main surface that divides the exhaust gas passage into a two-layer passage parallel to the top surface of the module container. And a plurality of a plurality of convex portions and a vent hole arranged on the main surface for conducting heat with the top surface of the module container,
7. The solid oxide according to claim 6, wherein, in the exhaust gas passage divided into the two layers, a convex portion of the heat transfer plate is not disposed in the vicinity of the upper exhaust gas inlet. Fuel cell device.

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