JP6219722B2 - Fuel cell power generator and fuel cell system - Google Patents

Description

  The present invention relates to a fuel cell power generation device that generates power by an electrochemical reaction between hydrogen and oxygen, a fuel cell system including the fuel cell power generation device, and a support structure.

  In recent years, fuel cells with high energy conversion efficiency and low environmental impact have attracted attention. As one of such fuel cells, a solid oxide fuel cell that operates at a high temperature of 600 ° C. or higher is known. The fuel cell of the solid oxide fuel cell has various cross-sectional structures such as a cylindrical shape, an elliptical shape, and a rectangular shape as described in Patent Document 1, for example. As a layer structure of a fuel cell, a structure having an anode electrode inside and a cathode electrode outside, and a structure having a cathode electrode inside and an anode electrode outside are generally known.

  For example, a structure disclosed in Patent Document 2 is known as a solid oxide fuel cell. In these structures, a cell stack in which a plurality of fuel cells are arranged with a current collecting member interposed therebetween, and a reformer for performing a reforming reaction are arranged in a box for generating power internally. Has been. Generally, in these structures, a pipe for supplying raw fuel or reformed water to the reformer is inserted through a through hole provided in the box. Further, in this structure, in order to heat the reformer, the combustion heat of the burner for raising the temperature of the cell stack to the operating temperature and the combustion heat of the off gas of the cell stack are used. In this structure, the exhaust gas and unused off gas are filled in the box. Therefore, it is necessary to suppress the combustion exhaust gas and off-gas from leaking out from the gap between the box and the pipe in the through hole provided in the box.

  On the other hand, for example, Patent Document 3 includes a cover plate that covers the outer through hole from the outside, the cover plate has a mounting hole for inserting the insertion tube, and the cover plate and the insertion tube are fixed by welding. The technology to do is described.

JP 2009-021195 A JP 2006-269332 A JP 2010-044992 A

  However, in the conventional structure described above, due to the thermal expansion of the reformer, a stress is generated in the connection portion between the pipe connected to the reformer and the box body, and the connection portion is broken by this stress, and the inside of the box body is damaged. There was a possibility that the combustion exhaust gas and off gas would leak out. In this case, since the heat energy of the leaked combustion exhaust gas or off gas cannot be used for heating the reformer or the like, the energy efficiency of the entire fuel cell is lowered.

  The present invention has been made in view of such problems, and in a fuel cell power generator in which a reformer and a cell stack are arranged inside a box, and a fuel cell system including the fuel cell power generator, It aims at providing the technique which suppresses that a combustion exhaust gas and off-gas leak.

In order to solve the above-described problems, a fuel cell power generation device according to an aspect of the present invention generates a fuel cell that is arranged above a cell stack and that is supplied to the cell stack. Therefore, a reformer extending along the arrangement direction of the fuel cells, a manifold for fixing the cell stack, connected to the reformer, and supplying the generated fuel gas to the cell stack, A reformed gas supply pipe that connects the manifold and the reformer, and a first cell that accommodates the cell stack, the manifold, the reformed gas supply pipe, and the reformer, and is located on the longitudinal extension of the reformer A box having at least one box through hole provided on the side surface, a substantially columnar support member for supporting the reformer in the box by penetrating the box through the box through hole, Portion both is secured to the outer surface of the box in the box through holes comprises a guide portion having an insertion through-hole for slidably inserting the support member through the box body through hole, the. Between the upper part of the fuel battery cell and the reformer is an off-gas combustion part that burns unreacted reformed gas that was not used in power generation of the fuel battery cell, and the guide part allows the support member to be inserted A first housing having a flange portion formed with a first guide through-hole, and a flange portion formed with a second guide through-hole through which the support member is inserted, and fitted to the inner wall of the first housing; a second housing comprising a mating portion for coupling a flange portion of the first housing and the flange portion of the second housing is engaged in close contact, the first guide holes and the second guide holes the support member is inserted or press-fitted into a space formed between the first housing and the second housing in the insertion state, includes a sealing member having heat resistance, and a first housing Said second how Characterized in that does not have a gap between the ring.

According to this aspect, when the reformer is thermally expanded, the support member slides with respect to the guide portion while ensuring airtightness between the support member and the guide portion. Thereby, the stress which arises between a supporting member and a guide part can be reduced, and it is suppressed that damage arises between a supporting member and a guide part. As a result, the airtightness between the support member and the guide portion is sufficiently ensured, so that combustion exhaust gas and the like are prevented from leaking from between the support member and the guide portion. Similarly, when the reformer contracts as the temperature of the reformer decreases, the support member slides in the opposite direction with respect to the guide portion while ensuring airtightness. Thereby, an energy utilization factor can be improved by reducing the leakage of off-gas and combustion exhaust gas to the outside of the box. In addition, since the support member and the guide portion have a simple structure, both slidability and airtightness can be achieved efficiently with a small space and at a low cost.

  According to the present invention, leakage of combustion exhaust gas and off gas from the box can be suppressed.

FIG. 1A is a schematic diagram schematically showing a fuel cell system according to an embodiment. FIG. 1B is a schematic view schematically showing a fuel cell system having a water vaporization section in the reformer. FIG. 2 is a perspective view showing the structure of the fuel cell power generator according to the embodiment. FIG. 3 is a three-sided view schematically showing the fuel cell power generator according to the embodiment. 3A is a side view of the fuel cell power generation device of FIG. 2 as viewed in the positive direction of arrow X. FIG. FIG. 3B is a side view of the fuel cell power generator of FIG. 2 as viewed in the positive direction of the arrow Y. 3C is a plan view of the fuel cell power generation device of FIG. 2 as viewed in the negative direction of arrow Z. FIG. FIG. 4 is a side view showing a state in which the guide portion and the support member are attached to the fuel cell power generator according to the embodiment. FIG. 4A is a side view of the fuel cell power generator of FIG. 2 as viewed from the second side face in the negative direction of the arrow y. FIG. 4B is a side view of the fuel cell power generation device of FIG. 2 as viewed from the first side face in the positive direction of the arrow y. FIG. 5 is a perspective view schematically showing each member of the guide portion and the support member. FIG. 6A is a cross-sectional view illustrating a state before the guide portion and the support member are assembled. FIG. 6B is a cross-sectional view illustrating a state after the guide portion and the support member are assembled to the box. FIG. 7A is a plan view showing, as a reference example, a case where a guide portion is attached to the first side surface of the box and a guide portion is attached to the third side surface of the box perpendicular to the box. On the other hand, FIG. 7 (B) is a plan view showing a case where a guide portion is attached to the first side surface of the box body and a guide portion is attached to the second side surface of the box body opposite thereto as the plan view of FIG. is there. FIG. 8 is a cross-sectional view showing a modified example of the fastening means.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

(Embodiment)
FIG. 1A is a schematic diagram schematically showing a fuel cell system 1 according to an embodiment. FIG. 1B is a schematic view schematically showing the fuel cell system 1 having the water vaporization unit 39 in the reformer 30.

  The fuel cell system 1 includes a fuel cell power generator 10 and a hot water tank unit 11. In the present embodiment, the fuel cell power generation device 10 indicates a structure other than the hot water tank unit 11 in the fuel cell system 1, but may further include at least a part of the hot water tank unit 11, and other than the hot water tank unit 11. The structure may be further included.

  In the present embodiment, the fuel cell power generation apparatus 10 supplies fuel gas (reformed gas) obtained by steam reforming a hydrogen-containing fuel such as a hydrocarbon fuel that is a raw fuel and air that is an oxidant. It is a solid oxide fuel cell that receives and generates electricity. The fuel cell power generation apparatus 10 includes an anode 63, an electrolyte 62, a cell stack 60 having a cathode 64, an off-gas combustion unit 14, a reformer 30, and a water vaporization unit 39. A reformer 30 illustrated in FIG. 1A includes a reforming unit 40. As the cell stack 60, at least one known solid oxide fuel cell stack can be used. The anode 63 is supplied with hydrogen-rich reformed gas generated by reforming the raw fuel by the reforming unit 40. Here, the form which performs steam reforming with the reformer 30 using the steam which vaporized reformed water by the water vaporization part 39 is illustrated. The cathode 64 is supplied with an oxidizing agent such as air. The off gas combustion unit 14 burns off gas that has not been used for the reaction of the cell stack 60. The heat generated by the combustion of the off gas is used for the reforming reaction by the reforming unit 40 (arrow B). Further, this heat may be used for water vaporization by the water vaporization unit 39 (arrow B) or for heating the temperature of the cell stack 60 to the power generation start temperature (arrow A). Note that when the fuel cell system 1 is started, the reformer 30 may be heated using a known method such as separately providing a heater or utilizing an autothermal reforming reaction. Further, as shown in FIG. 1B, the reformer 30 may further include a water vaporization unit 39 in addition to the reforming unit 40. Or in the form which performs partial oxidation reforming instead of steam reforming in reforming part 40, water vaporization part 39 can be omitted.

  In addition, when a fuel containing sulfur such as LPG, city gas, or kerosene is used as the raw fuel for the reformed gas, it is preferable to further provide a desulfurization section 38 upstream of the reforming section 40. When a desulfurization agent that performs desulfurization at a temperature higher than normal temperature is used as the desulfurization agent that fills the desulfurization unit 38, the desulfurization unit 38 may be heated using heat generated by off-gas combustion (arrow B).

  The hot water tank unit 11 includes a hot water tank 13. The hot water tank 13 is supplied with water used as a heat medium and stored. The pump 12 disposed in the fuel cell power generation apparatus 10 circulates water between the heat exchanger 15 disposed in the fuel cell power generation apparatus 10 and the hot water storage tank 13 in the hot water storage tank unit 11. The heat of the high-temperature exhaust gas generated by the off-gas combustion or the exhaust gas heated by the heat generation of the cell stack 60 is heat-exchanged between the heat exchanger 15 and the heat medium (arrow C), and the hot water is stored in the hot water storage tank 13 as hot water. Heat is stored and hot water is supplied as needed.

  Next, the structure of the fuel cell power generation device 10 of the present embodiment will be described in more detail with reference to FIGS. FIG. 2 is a perspective view showing the structure of the fuel cell power generation device 10 according to the embodiment. FIG. 3 is a three-view diagram illustrating an outline of the fuel cell power generation device 10 according to the embodiment. FIG. 3A is a side view of the fuel cell power generation device 10 of FIG. FIG. 3B is a side view of the fuel cell power generation device 10 of FIG. 2 as viewed in the positive direction of the arrow Y. FIG. 3C is a plan view of the fuel cell power generation device 10 of FIG. 2 as viewed in the negative direction of the arrow Z. FIG. 4 is a side view showing a state in which guide portions 71, 72, 73, 74, 75, and support members 41, 42, 43, 44, 45, and 46 are attached to the fuel cell power generation device 10 according to the embodiment. FIG. 4A is a side view of the fuel cell power generation device 10 of FIG. 2 as viewed from the second side surface 17 in the negative direction of the arrow y. FIG. 4B is a side view of the fuel cell power generation device 10 of FIG. 2 as viewed from the first side face 16 in the positive direction of the arrow y.

  The fuel cell power generator 10 has a box 20 for generating power inside. Inside the box 20, a reformer 30, a cell stack 60, and a manifold 52 are arranged in this order toward the negative direction of the Z-axis. In the present embodiment, the reformer 30 shown in FIG. 1 (A) is used. In FIG. 2, the box body 20 is viewed as transparent for explanation. 2 and 3, the water vaporization section 39 and the desulfurization section 38 shown in FIG. 1 (A) are used, and in FIG. 2 and FIG. 4, the air inlet 27 and the exhaust gas outlet 28 shown in FIG. In FIG. 4, the box through holes 21, 22, 23, 24, 25, and 26 and the guide portions 71, 72, 73, 74, 75, and 76 shown in FIG. 4 are omitted.

  The fuel cell power generator 10 includes at least one cell stack 60. As the cell stack 60, for example, a fuel cell disclosed in Japanese Unexamined Patent Application Publication No. 2009-021195 can be used. The cell stack 60 has a structure in which a plurality of fuel cells are regularly arranged. Each fuel cell includes an anode 63, an electrolyte 62, and a cathode 64 as shown in FIG. A reformed gas is supplied to the anode 63, and an oxidant is supplied to the cathode 64. A current collecting member (not shown) is disposed between adjacent fuel cells. Adjacent fuel cells are continuously arranged so as to be in contact with each other through a current collecting member. Thereby, adjacent fuel cells are electrically connected in series. The fuel cell is provided with a positive current wiring 55 and a negative current wiring 56 extending from the current collecting member and penetrating through support members 45 and 46 described later. The positive current wiring 55 and the negative current wiring 56 are wiring through which an aggregated current flows. The current generated by the fuel battery cell is taken out through the positive current wiring 55 and the negative current wiring 56.

  The reformer 30 shown in FIGS. 2 and 3 reforms the raw fuel supplied from the outside, and generates a reformed gas supplied to the cell stack 60. The reformer 30 is horizontally disposed above the cell stack 60 (in the positive direction of the Z axis) with a predetermined distance from the cell stack 60. This interval corresponds to the off-gas combustion unit 14 in FIG. The reformer 30 of the present embodiment is a steam reformer. Examples of the steam reforming catalyst include a ruthenium catalyst and a nickel catalyst.

  The reformer 30 is connected to the manifold 52 via a reformed gas supply pipe 51. The reformed gas generated by the reformer 30 is supplied to each fuel cell included in the cell stack 60 via the reformed gas supply pipe 51 and the manifold 52.

  Support members 41 and 42 are fixed to the reformer first side surface 36. The support members 41 and 42 have a function of supporting the reformer 30 inside the box body 20. In the present embodiment, the support members 41 and 42 are metal cylindrical members having desired strength. The support member 41 can also serve as a raw fuel, and the support member 42 can also serve as piping (raw fuel introduction part 31 and reformed water introduction part 32) for introducing reformed water into the reformer 30, respectively. In the present embodiment, as shown in FIG. 1A, the reformed water is vaporized in the water vaporization unit 39, then flows through the support member 41 and is introduced into the reforming unit 40. On the other hand, as shown in FIG. 1B, in the case of the structure in which the reforming unit 40 and the water vaporization unit 39 are integrated, the reforming water remains in a liquid state on the support member 41 that is the raw fuel introduction unit 31. It may be distributed.

  In the fuel cell power generator 10 of the present embodiment, LPG gas (liquefied petroleum gas) is used as the raw fuel. As other raw fuels, hydrocarbon fuels such as methane, propane, butane, kerosene, and naphtha, and hydrogen-containing fuels such as methanol, ethanol, and dimethyl ether can be used.

  A part of the support members 43 and 44 is fixed to the reformer second side surface 37 facing the reformer first side surface 36. The support members 43 and 44 have a function of supporting the reformer 30 inside the box body 20. In the present embodiment, the support members 43 and 44 are metal cylindrical members having a desired strength, and the temperatures inside the reformer 30 are monitored at the tips of the support members 43 and 44. A pair of thermocouples 33 and 34 are provided, and thermocouple wiring is laid inside the support members 43 and 44.

  In the present embodiment, the example in which the support members 41, 42, 43, 44 have other functions in addition to the function of supporting the reformer 30 has been shown, but only the function of supporting the reformer 30 is shown. You may have. In that case, for example, the raw fuel introduction part 31 and / or the reforming water introduction part 32 may be provided separately from the support members 41 and 42 which are rod-like members that are not hollow. Further, in the reformer 30 in which the support members 43 and 44 do not include the thermocouples 33 and 34, the support members 43 and 44 that are rod-shaped members that are not hollow may be used.

  In the present embodiment, the box-type reformer 30 is exemplified, but the reformer 30 is a cylindrical reformer or a cylindrical double-pipe reformer as disclosed in Japanese Patent Application Laid-Open No. 2008-007371. May be. In this case, one surface is the reformer first side surface 36 and the other surface is the reformer second side surface 37.

  The box body 20 includes a box body first side surface 16 and a box body second side surface 17 that faces the box body first side surface 16. As shown in FIG. 3C, the box body first side surface 16 faces the reformer first side surface 36, and the box body second side surface 17 faces the reformer second side surface 37. Each of the box body first side surface 16 and the box body second side surface 17 is provided with at least one box body through hole. In the present embodiment, the box first side surface 16 is provided with box through holes 21 and 22 that are through holes for inserting support members 41 and 42 that support the reformer 30. The box body second side surface 17 is provided with box body through holes 23 and 24 which are through holes for inserting support members 43 and 44 that support the reformer 30. The support member 41 is inserted through a guide portion 71 fixed to the box through hole 21. Similarly, the support member 42 is in the guide part 72 fixed to the box body through hole 22, the support member 43 is in the guide part 73 fixed in the box body through hole 23, and the support member 44 is in the box body through hole. The guide portions 74 are fixed to the guide portions 74. As a result, the support members 41, 42, 43, and 44 support the reformer 30 that raises the temperature inside the box body 20. The structure of the guide portions 71, 72, 73 and 74 will be described later with reference to FIGS. 5 and 6 taking the guide portion 71 as an example.

  Further, as shown in FIG. 3C, box through holes 25 and 26 for inserting support members 45 and 46 are provided in the box second side surface 17 respectively. The support members 45 and 46 are slidably inserted into guide portions 75 and 76 fixed to the box through holes 25 and 26, respectively. The support members 45 and 46 are made of an insulating member, and are, for example, ceramic insulators having a glaze treatment on the surface. A positive current wiring 55 is laid inside the support member 45, and a negative current wiring 56 is laid inside the support member 46. In the present embodiment, the positive electrode current wiring 55 and the negative electrode current wiring 56 are laid inside the support members 45 and 46. In order to prevent leakage of off-gas, combustion exhaust gas, etc. from the inside of the box 20, at least a part of the inside of the support members 45 and 46 is sealed by a sealing member (not shown) having heat resistance and airtightness. In addition, the positive current wiring 55 and the negative current wiring 56 penetrate the sealing member, so that the airtightness inside the support members 45 and 46 is maintained.

  In the present embodiment, the positive electrode current wiring 55 and the negative electrode current wiring 56 protrude from the box through holes 25 and 26 provided in the box second side surface 17. The positive electrode current wiring 55 and the negative electrode current wiring 56 may protrude from the first side surface 16 by providing the box through holes 25 and 26 on the first side surface 16. Also, any one of the box through holes 25 and 26 is provided on the box first side face 16 so that either the positive current wiring 55 or the negative current wiring 56 is projected from the box first side face 16. May be. The support members 45 and 46 may have a function of supporting at least a part of the power generation unit 50. In the present embodiment, the power generation unit 50 refers to an assembly of the reformed gas supply pipe 51, the manifold 52 and the cell stack 60.

  Next, the flow paths of the fuel gas and the off gas in the box 20 of the fuel cell power generation apparatus 10 will be described with reference to FIGS. 1, 2, 3A, and 3B. 3A and 3B, solid arrows D indicate the flow of raw fuel and reformed gas, and dotted arrows E in FIGS. 3A and 3B indicate the flow of off-gas and combustion exhaust gas. Show. In the present embodiment, a case where LPG is used as a raw fuel will be described as an example.

  The LPG gas supplied from the support member 41 (raw fuel introduction section 31), which is a pipe for supplying raw fuel, is heated in the reforming section 40 by off-gas combustion described later. As a result, the LPG gas is heated to a temperature suitable for the reforming reaction. Similarly, the reformed water supplied from the support member 42 (reformed water introduction unit 32), which is a reforming water supply pipe, is heated in the water vaporization unit 39 shown in FIG. 1 to become steam. Water vapor is supplied from the water vaporization unit 39 to the reforming unit 40 and becomes a fuel gas in which LPG gas and water vapor are mixed. The fuel gas flows downstream in the reformer 30, and is supplied to the anode 63 of each fuel cell through the reformed gas supply pipe 51 and the manifold 52 (FIGS. 3A and 3B). Arrow D). Air is supplied to the cathode 64 of each fuel cell from an air inlet 27 provided at the bottom of the box 20. Thereby, a power generation reaction occurs in the fuel cell.

  Unreacted reformed gas (hereinafter referred to as anode off-gas) that has not been used for power generation of the fuel battery cell is discharged toward the reformer 30 from the upper part of the fuel battery cell. The anode off gas and the air (cathode off gas) which has not been subjected to the reaction among the air introduced from the air introduction port 27 is burned in the off gas combustion unit 14 between the cell stack 60 and the reformer 30. Thus, the reformer 30 is heated to about 600 to about 750 ° C. in a steady state. Since the reforming reaction is promoted by heating the reformer 30, the generation efficiency of the reformed gas is improved. The combustion exhaust gas is discharged from an exhaust gas outlet 28 provided in the ceiling portion of the box body 20 (arrow E in FIGS. 3A and 3B).

  In the present embodiment, for ease of explanation, the air inlet 27 is provided at the bottom of the box 20 and the exhaust gas outlet 28 is provided at the ceiling of the box 20, but the air inlet 27 and the exhaust gas are provided. The position of the outlet 28 is not limited to these. Further, in order to make the supply of the oxidant to the cathode 64 and the derivation of the combustion exhaust gas from the cell stack 60 more efficient, a gas flow path may be formed inside the box 20.

  Next, the structure of a guide part and a supporting member is demonstrated using FIG. 5 and FIG. A guide part is a member which inserts the support member which protrudes from a box body through-hole so that sliding is possible, is connected to a box body through-hole, and is fixed to a box outer surface. Here, the guide portion 71 and the support member 41 shown in FIGS. 3C and 4B will be described. However, the guide portions 72, 73, 74, and 46 of the support members 42, 43, 44, 45, and 46 are described. The same applies to attachment to 75 and 76.

  FIG. 5 is a perspective view schematically showing each member of the guide portion 71 and the support member 41. FIG. 6A is a cross-sectional view showing a state before the guide portion 71 and the support member 41 are assembled. FIG. 6B is a cross-sectional view illustrating a state after the guide portion 71 and the support member 41 are assembled to the box body 20.

  First, each member included in the guide portion 71 will be described with reference to FIGS. 5 and 6A. The guide portion 71 includes a first housing 80 that is a housing case, a sealing member 100, a spacer 110, a second housing 90 that is a housing lid, and a bolt 120. The first housing 80 is a bottomed container in which a flange portion 86 is provided at the end of the opening 85. The first housing 80 includes a first guide through hole 81 through which the support member 41 is inserted at the center of the bottom. The opening 85 has a larger cross-sectional area than the first guide through hole 81. A plurality of fastening holes 82 are provided in the flange portion 86 formed at the flange of the opening 85. In the present embodiment, the first housing 80 having a cylindrical cross section is illustrated, but the cross section of the inside 87 of the first housing 80 is not limited thereto, and may be, for example, a square shape.

The second housing 90 includes a fitting portion 93 inserted inside the first housing 80 and a flange portion 96. The length l ₃ of the fitting portion 93 of the second housing 90 is shorter than the depth l ₁ of the first housing 80. The second housing 90 includes a second guide through hole 91 into which the support member 41 is inserted in a state where the fitting portion 93 is inserted into the first housing 80. In the present embodiment, the second housing 90 in which the fitting portion 93 has a cylindrical shape is illustrated, but the cross section of the fitting portion 93 of the second housing 90 has the same shape as the cross section of the interior 87 of the first housing 80. If it is. For example, if the cross-sectional shape of the inside 87 of the first housing 80 is a hexagon, the cross-sectional shape of the fitting portion 93 is also a hexagon.

  The flange portion 96 of the second housing 90 has a fastening hole 92 at a position where it can be fastened to the fastening hole 82 of the first housing 80 in a state where the fitting portion 93 is inserted into the inside 87 of the first housing 80. Is provided. The first housing 80 and the second housing 90 are fastened by the bolts 120 in the fastening holes 82 and 92. The first housing 80 and the second housing 90 are preferably made of metal having heat resistance and desired strength.

The spacer 110 is a member inserted into the inside 87 of the first housing 80. The spacer 110 is formed with a through hole 111 that can penetrate the support member 41. Since the spacer 110 hardly shrinks in the thickness direction, the axial length l ₅ of the space 112 described later can be adjusted according to the thickness l ₄ (length in the central axis direction) of the spacer 110. In the present embodiment, the spacer 110 having a circular plate shape in cross section is illustrated, but the cross section of the spacer 110 may be the same shape as the cross section of the inside 87 of the first housing 80. For example, if the cross-sectional shape of the inside 87 of the first housing 80 is a hexagon, the spacer 110 is also a hexagonal flat plate.

  The sealing member 100 is a member for filling and sealing the space 112 by being inserted or press-fitted into the space 112 formed by the support member 41, the first housing 80 and the second housing 90. And flexibility. A through hole 101 is formed in the sealing member 100 at least after the guide portion 71 is assembled. Since the sealing member 100 only needs to seal the space 112, the shape before being inserted or press-fitted into the space 112 is not particularly limited.

The sealing member 100 has an outer diameter that can be fitted into the inner portion 87 of the first housing 80, for example, and a through hole 101 into which the support member 41 can be slidably inserted is formed concentrically with the outer diameter. It is a cylindrical body. Considering the deformability of the sealing member 100, the axial length l ₂ of the cylindrical sealing member 100 is a length that can maintain a length ₁₅ described later in a state where the guide portion 71 is assembled. That's fine.

  In addition, when the sealing member 100 before filling is in the form of a sheet, a substantially cylindrical shape is formed by winding the sheet-like sealing member 100 so as to form a through hole 101 through which the support member 41 is slidably inserted. The interior of the space 112 can be easily filled and sealed. In addition, when the sealing member 100 before filling is string-shaped, the string-shaped sealing member 100 is wound in a coil shape so as to form a through hole 101 through which the support member 41 is slidably inserted. A shape can be formed, and the space 112 can be easily filled and sealed. It is also possible to easily fill and seal the interior of the space 112 by winding the sheet-like or string-like sealing member 100 directly around the support member 41 and then inserting or press-fitting the sealing member 100 into the first housing 80. it can.

As a material of such a sealing member 100, an expanded graphite-containing member containing expanded graphite is preferable from the viewpoints of heat resistance, flexibility, self-lubricating property, durability, airtightness, and cost. As the expanded graphite-containing member, Graseal packing TOMBO series (Nichias Co., Ltd.) in which a metallic wire is sandwiched between expanded graphite materials can be suitably used. The expanded graphite-containing member has flexibility and also has a self-lubricating property inherent to graphite. Therefore, the space 112 can be easily sealed by press-fitting the expanded graphite-containing member, and the support member 41 can be allowed to slide while maintaining airtightness. In addition to the expanded graphite-containing member, a ceramic fiber blanket can also be used. It is desirable to determine the lengths l ₁ to l ₄ and the length l ₅ described later according to the type of these sealing members.

As shown in FIG. 6B, the sealing member 100, the spacer 110, and the fitting portion 93 of the second housing 140 are inserted into the interior 87 of the first housing 80 so that the support member 41 can penetrate. . Then, the flange portion 86 of the first housing 80 and the flange portion 96 of the second housing 90 are fixed by the bolts 120 as fastening means, whereby the insertion through hole 122 is formed. The insertion through hole 122 is a through hole of the guide part 71 in a state where the guide part 71 is assembled. A support member 41 protruding from the box 20 is inserted into the insertion through hole 122. In this case, a space 112 is formed by the first housing 80 and the spacer 110. The length of the space 112 in the direction of the central axis L is l ₅ (= l ₁ −l ₃ −l ₄ ).

The sealing member 100 is filled in the space 112 so that the axial center of the through hole 101 provided in the sealing member 100 is substantially coaxial with the central axis L of the space 112. The length l ₂ in the axial direction of the sealing member 100 before assembly is longer than the length l _{5 in the} direction of the central axis L of the space 112. Therefore, when the second housing 90 is fixed to the first housing 80 by tightening the bolts 120, the sealing member 100 is press-fitted in the direction of the arrow P and contracts. If the support member 41 is not inserted, the through hole 101 may not be a straight hole due to the deformation of the sealing member 100. Therefore, it is sufficient that the axis of the through hole 101 is substantially parallel to the central axis L so that at least the support member 41 can be inserted into the through hole 101.

In the present embodiment, an example in which the spacer 110 is used for the guide portion 71 is shown, but the spacer 110 may not be used. Even in this case, the axial length l ₂ of the sealing member 100 before assembly is the length l in the central axis L direction of the space 112 formed between the first housing 80 and the second housing 90. Longer than ₅ (= l ₁ −l ₃ ).

  In the present embodiment, the total stress generated between the support member and the sealing member due to the thermal expansion of the reformer 30 is about, for example, about both the box first side surface 16 and the box second side surface 17. 3.4 kN. On the other hand, the proof stress of the support member 41 at a high temperature is, for example, about 3.8 kN or more. Therefore, the support member 41 can withstand the stress received from the reformer 30 and the stress received from the sealing member 100 (arrow Q in FIG. 6B) even at high temperatures.

  Further, the total of the reciprocating resistance (the force required when the two members are slid back and forth) with respect to the support member of the sealing member 100 is about 766 N on the box first side surface 16, for example, and the box body second. In the side surface 17, it is about 383N. This value is smaller than the total load applied to the support member due to the thermal expansion of the reformer 30, and smaller than the load at which the support member breaks due to the tensile strength. Therefore, by using the above-described material as the sealing member 100, the support member 41 can slide without breaking with respect to the sealing member 100.

  In the present embodiment, the container-shaped first housing 80 and the lid-shaped second housing 90 are used as the housing of the guide portion 71. However, as long as the space 112 can be formed in the assembled state. The first housing 80 and the second housing 90 are not limited to these shapes. For example, the space 112 may be formed by combining two container-like housings. Further, the number of parts of the housing is not limited to two.

  Further, in the present embodiment, the sealing member 100 is elastically deformed in a state where the airtightness between the support members 41, 42, 43, 44 and the guide portions 71, 72, 73, 74 is ensured. Therefore, each insertion hole (the first guide through hole 81, the second guide through hole 91, the through hole 101, the through hole 111, and the insertion through hole 122 formed from these) and the support member 41 are not necessarily coaxial. Need not be. Further, each insertion hole can allow clearance so that the inserted or press-fitted sealing member 100 does not overflow outside due to the sliding of the support member. However, the axial shift and clearance between the support members 41, 42, 43, and 44 and the members included in the guide portions 71, 72, 73, and 74 are improved by improving the processing accuracy and assembly accuracy of each member. It is preferable to make it as small as possible.

  As described above, according to the present embodiment, when the reformer 30 is thermally expanded during the power generation of the cell stack 60, the space between the support members 41, 42, 43, and 44 and the guide portions 71, 72, 73, and 74 is increased. The support members 41, 42, 43, 44 slide with respect to the guide portions 71, 72, 73, 74 while ensuring airtightness. As a result, the stress generated between the support members 41, 42, 43, 44 and the guide portions 71, 72, 73, 74 can be reduced, and the support members 41, 42, 43, 44 and the guide portions 71, 72 can be reduced. , 73 and 74 are prevented from being damaged. As a result, the airtightness between the support members 41, 42, 43, 44 and the guide portions 71, 72, 73, 74 is sufficiently secured, so that the support members 41, 42, 43, 44 and the guide portions 71, Leakage of off-gas, combustion exhaust gas, etc. in the box 20 from between 72, 73, 74 is suppressed. Similarly, when the reformer 30 contracts as the temperature of the reformer 30 decreases, the support members 41, 42, 43, and 44 support the guide portions 71, 72, 73, and 74 while ensuring airtightness. It slides in the opposite direction. Thereby, the energy utilization factor can be improved by reducing leakage of off-gas and combustion exhaust gas in the box 20. Further, since the support members 41, 42, 43, and 44 and the guide portions 71, 72, 73, and 74 have a simple structure, it is possible to achieve both slidability and airtightness efficiently in a small space and at a low cost. it can.

  Similarly, the guide portions 75 and 76 may be attached to the support members 45 and 46 in which the positive current wiring 55 and the negative current wiring 56 are laid. Thereby, the supporting members 45 and 46 slide with respect to the guide parts 75 and 76, and the airtightness between them is sufficiently ensured. Therefore, as with the reformer 30, even if the positive current wiring 55 and the negative current wiring 56 themselves and the power generation unit 50 provided with them expand at a high temperature, they are fixed to the bottom surface of the box 20. The stress generated between the power generation unit 50 and the current wiring fixed to the box second side surface 17 is alleviated, and leakage of combustion exhaust gas or the like is suppressed.

  Further, by using a fuel cell power generator in which airtightness between the support member and the guide portion is sufficiently ensured and combustion exhaust gas or the like is suppressed from leaking between the support member and the guide portion, a fuel cell is obtained. The thermal efficiency of the system can be improved.

  Next, the fixing position of the support member in the box 20 will be described. FIG. 7A shows, as a reference example, a case where guide parts 71 and 72 are attached to the box first side face 16 and guide parts 73 and 74 are attached to the box third side face 18 perpendicular thereto. It is a top view. On the other hand, FIG. 7B is a plan view of FIG. 2, in which guide parts 71 and 72 are attached to the box first side face 16, and guide parts 73 and 74 are attached to the box second side face 17 opposite thereto. It is a top view which shows the case where it was done. In FIG. 7B, the support member 45 and the support member 46 in FIG. 2 are omitted.

  In FIG. 7A, when the fuel cell power generation device 10 generates power and the inside of the box 20 is heated, the reformer 30 expands. As a result, the reformer 30 and the support members 41, 42, 43, 44 are displaced in the oblique direction as indicated by dotted lines, and the box through holes 21, 22, 23, 24 and the guide portions 71, 72, 73, 74. In some cases, stress acts near the guide through hole. In this case, if the support members 41, 42, 43, and 44, the box 20, the guide portions 71, 72, 73, and 74 are deformed or damaged, the airtightness becomes insufficient. As a result, the off-gas, combustion exhaust gas, and the like leak from the box 20, and the energy utilization rate of the fuel cell power generation device 10 may be reduced.

  On the other hand, in FIG. 7B, the guide portions 73 and 74 are attached to the box second side surface 17 facing the box first side surface 16. In this case, the supporting members 41 and 42 and the supporting members 43 and 44 are fixed to the opposing box first side 16 and box second side 17 respectively. In this structure, even when the reformer 30 expands due to heat, only the force parallel to the axis of the guide through-hole acts on the guide portions 71, 72, 73, 74, so the support members 41, 42 and the support member 43 , 44 are smoothly displaced in opposite directions. Therefore, sufficient airtightness is ensured between the support members 41, 42, 43, and 44 and the guide portions 71, 72, 73, and 74. Thereby, it is possible to reduce the stress acting near the box through hole and the guide through hole of the guide portion as shown in FIG. 7A, and the support members 41, 42, 43, 44, the box 20, the guide portion 71, The deformation and damage of 72, 73, 74, etc. can be suppressed. As a result, it is possible to further improve the energy utilization rate in the fuel cell power generation device 10 by reducing the leakage of off gas, combustion exhaust gas, and the like from the inside of the box 20 to the outside.

  In the case of FIG. 7B, when the box 20 is viewed in a plan view from the direction perpendicular to the box first side face 16 and the box second side face 17, that is, from the Y-axis direction in FIG. A part of the cross section of the support member 41 attached to the side face 16 and a part of the cross section of the support member 44 attached to the box second side face 17 are overlapped. Similarly, the cross section of the support member 42 attached to the box first side surface 16 and the cross section of the support member 43 attached to the box second side surface 17 also overlap. This further reduces the stress acting near the box through hole and the guide through hole of the guide part, and the contact position between the support members 41, 42, 43, 44 and the guide parts 71, 72, 73, 74 is further improved. It can be made to shift smoothly.

  A support structure including the above-described support member and guide portion may be used for the structure of the fuel cell power generation device 10 other than the reformer 30 and the power generation unit 50. In the present embodiment, the solid oxide fuel cell is shown as an example, but the above-described support member and guide portion may be used for fuel cell power generators other than the solid oxide fuel cell. As a fuel cell power generator other than the solid oxide type, for example, a phosphoric acid fuel cell or a molten carbonate fuel cell power generator can be used.

  Furthermore, a support structure including the above-described support member and guide portion may be used for structures other than the fuel cell power generator. The support structure in this case supports the temperature raising member whose temperature rises by heat by the support member. The temperature raising member is housed in the temperature raising member storage container, and the support member is slidably inserted into a guide provided in the temperature raising member storage container. Accordingly, when the temperature raising member is thermally expanded, the support member slides with respect to the insertion member while ensuring airtightness between the support member and the insertion member. Thereby, the stress which arises between a supporting member and an insertion member can be reduced, and it is suppressed that damage arises between a supporting member and an insertion member. Therefore, the temperature raising member whose temperature rises by heat can be stably held in the temperature raising member storage container. In addition, since the support member and the guide portion have a simple structure, both slidability and airtightness can be achieved efficiently with a small space and at a low cost. The temperature raising member may itself be a member that generates heat.

(Modification)
As the fastening means, the structure shown in FIGS. 8A to 8C can be used in place of the bolt 120 shown in FIGS. FIG. 8 is a cross-sectional view showing a modified example of the fastening means. FIG. 8A shows that the first housing 80 and the second housing 90 do not include the flange portions 86 and 96, and a caulking portion 88 is formed by caulking the second housing 90 at the opening 85 of the first housing. It is sectional drawing of the structure made to fix. In FIG. 8B, a female screw part 89 is formed on the inner wall near the opening 85 of the first housing 80, a male screw part 99 is formed on the fitting part of the second housing part, and they are screwed together. It is sectional drawing of the structure made to make. FIG. 8C is a cross-sectional view of a structure in which the first housing 80 and the second housing 90 are fixed by forming the welded portion 124 by welding. In the case of FIG. 8C, the second housing 90 may have a shape including the fitting portion 93 or may be a flat plate not including the fitting portion 93. In any case, the spacer 110 can be omitted.

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added based on the knowledge of those skilled in the art. The form can also be included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 10 Fuel cell power generation device, 20 Box body, 21 Box body through-hole, 41 Support member, 71 Guide part, 80 1st housing, 81 1st guide through-hole, 90 2nd housing, 91 2nd guide through-hole Hole, 100 sealing member, 122 through-hole for insertion

  INDUSTRIAL APPLICABILITY The present invention can be used in fields related to a fuel cell power generation device that generates power by an electrochemical reaction between hydrogen and oxygen, a fuel cell system including the fuel cell power generation device, and a support structure.

Claims (9)

A cell stack in which a plurality of fuel cells are arranged; and
A reformer disposed above the cell stack for generating fuel gas to be supplied to the cell stack and extending along an arrangement direction of the fuel cells;
A manifold for fixing the cell stack and connected to the reformer and supplying the generated fuel gas to the cell stack;
A reformed gas supply pipe connecting the manifold and the reformer;
The cell stack, the manifold, the reformed gas supply pipe, and the reformer are accommodated, and at least a box through-hole provided in a first side surface located on an extension line in the longitudinal direction of the reformer is provided. A box having one;
A substantially columnar support member that supports the reformer in the box by penetrating the box through the box through-hole;
At least a part is fixed to the outer surface of the box body in the box body through hole, and includes a guide portion having an insertion through hole for slidably inserting the support member penetrating the box body through hole. ,
Between the upper part of the fuel cell and the reformer is an off-gas combustion unit that burns unreacted reformed gas that was not used in power generation of the fuel cell,
The guide portion includes a first housing having a flange portion in which a first guide through-hole through which the support member is inserted and a flange portion in which a second guide through-hole through which the support member is inserted are formed. a, the second housing including a fitting portion for fitting with the inner wall of the first housing, and the flange portion of the flange portion of the first housing the second housing is engaged in close contact, is inserted or press-fitted into a space formed between the first guide holes and the second guide holes in the support member and the second housing said first housing and in a state in which is inserted And a sealing member having heat resistance , and there is no gap between the first housing and the second housing . The box body has a second side surface facing the first side surface,
Each of the first side surface and the second side surface is provided with at least one box through hole and the guide portion,
The support member inserted into the guide through hole of the guide portion fixed to the first side surface and the second side surface is attached to the reformer. The fuel cell power generator described in 1.   When the box is viewed in plan from a direction perpendicular to the first side surface and the second side surface, the box is attached to the cross section of the support member attached to the first side surface and the second side surface. The fuel cell power generator according to claim 2, wherein at least a part of a cross section of the support member overlaps.   In each of the first side surface and the second side surface, the total reciprocating resistance in one or more of the support members inserted through each side surface is greater than the total stress generated by thermal expansion of the reformer. The fuel cell power generator according to claim 2, wherein the fuel cell power generator is smaller. Fuel cell power plant of length before Symbol fitting portion according to any one of the preceding claims, characterized in that less than the depth of the inner space of the first housing.   The fuel cell power generator according to any one of claims 1 to 5, wherein the sealing member is a member containing expanded graphite.   The fuel supply pipe for supplying at least one of the support members to the reformer through the box through-hole is a fuel supply pipe. The fuel cell power generator described.   The cell stack further includes a plurality of current wirings for extracting a current generated from the fuel cell, and the current wiring includes a second support member made of an insulating member provided therein. The fuel cell power generator according to any one of the above.   A fuel cell system including the fuel cell power generator according to claim 1.

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