JP5436196B2 - Power generator - Google Patents

Description

  The present invention relates to an apparatus for generating electric power using a solid oxide fuel cell.

  As described in Patent Document 1, a power generation apparatus using a fuel battery cell using a solid oxide is known. In this power generation device, power is generated by reacting a reformed gas and an oxygen-containing gas in a fuel cell.

  A fuel battery cell using a solid oxide efficiently generates power in a high temperature environment of about 800 ° C. Therefore, in this power generation device, the oxygen-containing gas is heated in advance with heat generated in the fuel battery cell, and then the oxygen-containing gas is supplied to the fuel battery cell. Specifically, in this power generation device, a gas supply member for supplying an oxygen-containing gas is disposed between the fuel cells extending in a columnar shape. As a result, the oxygen-containing gas flowing through the gas supply member is heated by the radiant heat and conduction heat from the fuel cells arranged around it, and the heated oxygen-containing gas is supplied to the fuel cells. .

JP 2006-19084 A

  The inventors of the present specification have devised a power generation device illustrated in FIG. 4 in order to make the power generation device more compact. FIG. 4 shows the power generation unit 110 housed inside the casing of the power generation apparatus. In this power generation unit 110, a reformer 140 that reforms steam and fuel gas into reformed gas on a fuel cell unit 120 in which a plurality of fuel cells 122 are erected in parallel; The vaporizer 150 to be generated is placed in order.

  In the fuel cell unit 120, a plurality of fuel cells 122 are erected in parallel, and the intervals between the adjacent fuel cells 122 are narrower than those of the conventional one and are arranged close to each other. Further, in this power generation device, since a space for providing a gas supply member is not provided between adjacent fuel cells 122, oxygen is contained in a plurality of fuel cells 122 on the side of the fuel cell unit 120. A common gas supply member 160 that supplies gas is disposed. In this power generation device, a plurality of fuel cells 122 are shared instead of arranging adjacent fuel cells 122 close to each other and not providing individual gas supply members for each fuel cell 122. By providing the common gas supply member 160, the power generator is made compact.

  The common gas supply member 160 is formed in a hollow flat plate shape. The upper end of the common gas supply member 160 is closed. In the lower half of the common gas supply member 160, a blocking groove 165 for diversion is formed intermittently in the horizontal direction. At the lower end of the common gas supply member 160, an opening 166 that opens downward and a portion that is closed by a branching closing groove 165 are alternately formed in the horizontal direction. Two gas introduction pipes 161 communicating with the inside of the common gas supply member 160 are connected to the upper part of the side surface of the common gas supply member 160. The oxygen-containing gas flows into the common gas supply member 160 through the gas introduction pipe 161 and then flows downward. The oxygen-containing gas is divided so as to be uniformly supplied to each fuel cell 122 by the shunting groove 165. It is ejected from an opening 166 provided at the lower end of the supply member 160 and supplied to each fuel cell 122. The oxygen-containing gas is heated by radiant heat and conduction heat from the fuel cell 122 while flowing downward in the common gas supply member 160.

  When the common gas supply member 160 is used, the outer dimensions of the fuel cell unit 120 can be reduced. However, only one surface of the common gas supply member 160 faces the fuel cell 122. Therefore, in this power generation device, the oxygen-containing gas cannot sufficiently transfer heat from the fuel cell 122 compared to the conventional configuration in which the fuel cell is arranged around the gas supply member, Heating of the oxygen-containing gas becomes insufficient. Therefore, it has been found that the oxygen-containing gas supplied to the fuel battery cell 122 cannot be appropriately heated, and the power generation efficiency in the fuel battery cell 122 may be reduced.

  The present invention has been made in view of such circumstances, and an object of the present invention is to make the fuel cell unit compact and to appropriately heat the oxygen-containing gas to suppress a decrease in power generation efficiency. An object of the present invention is to provide a solid oxide type power generation device that can be used.

Generator according to the invention described herein, the fuel cell unit which a plurality of fuel cells are erected in parallel, supplies the oxygen-containing gas to the plurality of fuel cells, a plurality And a common gas supply member disposed on the side of the fuel cell unit so as to face the side surface of the fuel cell. Each of the plurality of fuel cells is a solid oxide fuel cell having a columnar shape and a reformed gas passage penetrating in the axial direction. The common gas supply member includes an inner plate made of a heat conductive material and disposed on the fuel cell unit side, an outer plate facing the inner plate, and a part of the inner plate and the outer plate over a plurality of stages and rows. than other parts partially meandering oxygen-containing gas by proximity to an obstacle to the flow of oxygen-containing gas, and a plurality of obstruction that cause turbulence.

  In the above configuration, since the common gas supply member is arranged on the side of the fuel cell unit, it is necessary to provide a gas supply member between adjacent fuel cells, unlike the conventional individual supply method. Absent. According to the said structure, a space | interval can be narrowed between adjacent fuel cells and a fuel cell unit can be made compact. Furthermore, since a common gas supply member shared by a plurality of fuel cells is provided, the entire power generation apparatus can be made compact compared to the case where a gas supply member is provided for each fuel cell individually. You can also.

  In the above configuration, in the common gas supply member, the inner plate disposed on the fuel cell unit side is first heated by radiant heat and conduction heat from the fuel cell. Since the oxygen-containing gas flows in a meandering manner in the passage formed in the common gas supply member, the flow rate of the oxygen-containing gas is increased, and the flow becomes turbulent. The opportunity for the oxygen-containing gas to contact the inner plate increases. As a result, the heat exchange between the inner plate and the oxygen-containing gas is actively performed, so that the oxygen-containing gas can be appropriately heated by the heat of the fuel cell absorbed by the inner plate, thereby forming the obstacle. The power generation efficiency of the fuel cell can be improved as compared with the case where a common gas supply member that is not used is used. Therefore, it is possible to suppress a reduction in power generation efficiency of the fuel battery cell while achieving compactness.

  In the above configuration, when the inner plate and the outer plate of the common gas supply member are close to each other, a part of at least one of these plates is bent so as to protrude toward the other plate, and the two plates are formed. It is close and other members (projections etc.) attached to at least one of these plates are close to the other plate. Further, the degree of proximity is not limited, and in the obstacle portion, a gap may be formed between the inner plate and the outer plate, or the inner plate and the outer plate may be in contact with each other.

Further, on the common gas supply member of the power generation device described herein, as a portion corresponding to the downstream side of the flow of the reformed gas in the plurality of fuel cells, failure of several are provided densely .

  In the fuel cell, since the reformed gas and the oxygen-containing gas react to generate electricity and generate heat, the high-temperature exhaust gas flows to the downstream side of the gas flow in the fuel cell and is used for this power generation. Gas is heated and flows downstream. Therefore, since these gases flow toward the downstream side while gradually raising the temperature, in the fuel cell, the temperature on the downstream side tends to be higher than the upstream side of the gas flow. In this regard, in the above configuration, in the common gas supply member, since the degree of meandering of the oxygen-containing gas increases corresponding to the portion where the fuel cell becomes high temperature, the heat of the fuel cell passes through the inner plate to the oxygen-containing gas. The part which is supplied more and tends to become high temperature in the fuel battery cell can increase the heat radiation amount. Therefore, the temperature gradient generated in the fuel cell can be corrected to make the temperature of the entire fuel cell uniform, and this part can be deteriorated due to the fuel cell partially becoming too hot. Further, it is possible to prevent the power generation efficiency at this portion from being lowered due to the fuel cell partially becoming too low in temperature.

  According to the power generation device described in the present specification, the fuel cell unit can be made compact, and the oxygen-containing gas can be appropriately heated to suppress a decrease in power generation efficiency.

FIG. 3 is a perspective view illustrating a power generation unit of the power generation apparatus according to the first embodiment. FIG. 2 is an end view schematically showing a cross-sectional structure taken along line II-II in FIG. 1. The end elevation which shows typically the cross-sectional structure corresponding to FIG. 2 of the electric power generating apparatus of Example 2. FIG. The perspective view which shows the electric power generation unit which this inventor devised.

The technical features of the embodiments described below are listed.
(Feature 1) The common gas supply member is made of metal. Thus, the oxygen-containing gas is efficiently heated by the heat from the fuel battery cell.
(Characteristic 2) The common gas supply member of the power generator has an obstacle portion formed close to the outer plate by projecting the outer plate side surface of the inner plate to the outer plate side. The inner plate is recessed toward the outer plate at the site where the obstacle is formed. Thereby, since the area of the inner plate facing the fuel cell can be increased, the inner plate can absorb more conduction heat from the fuel cell.
(Characteristic 3) The common gas supply member extends above the upper end of the fuel cell unit, and the oxygen-containing gas flowing above the common gas supply member is configured to exchange heat with the exhaust gas generated by off-gas combustion. Has been. Thus, the oxygen-containing gas is heated by the exhaust gas when flowing over the common gas supply member.
(Feature 4) The common gas supply member is provided with a plurality of shunting grooves for shunting in parallel with a plurality of fuel cells. As a result, the oxygen-containing gas flowing through the common gas supply member can be evenly supplied to each of the fuel cells.

A power generation apparatus according to Embodiment 1 will be described with reference to FIGS. 1 and 2.
FIG. 1 is a perspective view showing a power generation unit 10 housed in the power generation apparatus in the power generation apparatus according to this embodiment. In the following description, for the sake of convenience, the direction indicated by the arrow A in FIG.

  The power generation unit 10 is accommodated in a casing formed of a heat insulating agent (not shown). Inside the casing, there are an exhaust gas passage for exhausting the exhaust gas generated in the power generation unit 10 to the outside of the casing, an oxygen-containing gas passage for supplying oxygen-containing gas outside the casing to the common gas supply member 60, and the like. Is formed.

  The power generation unit 10 includes a fuel cell unit 20, a reformer 40, a vaporizer 50, and two common gas supply members 60. In the power generation unit 10, the reformer 40 and the vaporizer 50 are arranged in order from the bottom so as to be stacked on the fuel cell unit 20, and each common gas supply member 60 includes these three members 20, 40. , 50 are arranged facing each other so as to cover both sides thereof. In FIG. 1, the configuration of one of the two common gas supply members 60 on the front side in the drawing is shown in detail, and the internal gas flow is shown by arrows.

  The vaporizer 50 vaporizes water to generate water vapor, and is composed of a metal plate heat exchanger that is bent up and down. As shown in FIG. 1, the vaporizer 50 has substantially the same width as the width of the reformer 40 in the width of both ends in the lateral direction of the fuel cell unit 20 and the width of the center. However, the width of the portion slightly inside from both ends is shorter than the width of the reformer 40. Although not shown, the vaporizer 50 has a water channel through which water or water vapor flows. The vaporizer 50 has a water supply pipe 51 connected to a side surface located on the outer side on one end side, and two water vapor supply pipes 52 connected to a side surface located on the inner side on the other end side.

  As a heat source for vaporizing water in the vaporizer 50, combustion heat of off-gas of the fuel battery cell is used. In other words, the vaporizer 50 is supplied with exhaust gas generated by off-gas combustion in the fuel cell unit 20, as will be described later. Therefore, the water that has flowed into the water channel of the vaporizer 50 through the water supply pipe 51 is heated by exchanging heat with the exhaust gas flowing around the vaporizer 50 to become water vapor. This water vapor flows out of the water vapor supply pipe 52 and is modified. It is supplied to the quality device 40.

  The reformer 40 generates reformed gas used for power generation reaction in the fuel battery cell 22. The reformer 40 has a meandering path formed inside a metal container, and the reforming catalyst is filled in the path. The reformer 40 is formed in the same rectangular shape as the plan view of the fuel cell unit 20 in a plan view, and is disposed above the fuel cell unit 20 so as to be adjacent to the fuel cell unit 20.

  The reformer 40 has a flat shape as a whole and has a stepped shape with only one end projecting. In the reformer 40, a fuel gas supply pipe 45 for supplying fuel gas is connected to a side surface located on the outer side of the protruding one end side. In this embodiment, for example, a gas mainly composed of methane is used as the fuel gas. An example of such a gas is city gas.

  In the reformer 40, the downstream ends of the two steam supply pipes 52 are connected to the side surface located on the inner side of the projecting one end side so as to face the fuel gas supply pipe 45. Thereby, the water vapor generated in the vaporizer 50 is supplied to the reformer 40 through the water vapor supply pipe 52.

  The fuel gas and water vapor that have flowed into the reformer 40 are reformed by the reforming catalyst into a reformed gas composed of hydrogen and carbon monoxide when flowing through the reformer 40. In addition, as shown in FIG. 2, the reformer 40 has an exhaust gas hole 48 penetrating vertically. The exhaust gas hole 48 is for allowing high-temperature exhaust gas generated by the combustion of off-gas in the fuel cell unit 20 to pass from the fuel cell unit 20 side to the vaporizer 50 side.

  Since the reforming reaction involves endotherm, the reformer 40 needs to be heated to a suitable temperature. In addition, since the suitable reforming temperature of the fuel gas which has methane as a main component is 600 degreeC or more, in this Example, it is preferable that the reformer 40 is heated so that it may become 600 degreeC or more. In this respect, the reformer 40 is disposed above the fuel cell unit 20 and is disposed on the side of the fuel cell unit 20 where off-gas is combusted, as will be described later. Accordingly, the reformer 40 is directly heated at the lower part thereof by the combustion of the off gas and is also heated by exchanging heat with the exhaust gas flowing through the exhaust gas holes 48, so that the combustion heat of the off gas of the fuel cell unit 20 is reformed. It is used for reforming reaction.

  As shown in FIG. 1, two reformed gas supply pipes 31 are connected to both sides of the side surface of the reformer 40 where there is no step. As a result, the high-temperature reformed gas reformed by the reformer 40 flows through the reformed gas supply pipe 31 and is sent into the manifold 30.

  As shown in FIG. 1, the fuel cell unit 20 includes a plurality of fuel cells 22. Each fuel cell 22 is formed by stacking a plurality of unit fuel cells and extends in a columnar shape. The plurality of fuel cells 22 are erected in parallel on the manifold 30 disposed below the fuel cell unit 20 so as to be close to each other. The plurality of fuel cells 22 are arranged in multiple rows in the horizontal direction of the power generation unit 10, and are arranged in two rows in a direction orthogonal to the horizontal direction of the power generation unit 10. In the present embodiment, the power generation device can be made compact by arranging the fuel cells 22 closely.

  As shown in FIG. 2, a plurality of reformed gas passages 23 penetrating in the direction in which the fuel cell 22 extends, that is, in the vertical direction, are formed in parallel inside the fuel electrode of the fuel cell 22. When the reformed gas is supplied to the reformed gas passage 23, the fuel cell 22 supplies the reformed gas supplied to the reformed gas passage 23 to the oxygen-containing gas existing around the fuel cell 22. To generate electricity. In this embodiment, the reformed gas is composed of hydrogen and carbon monoxide, and air is used as the oxygen-containing gas. An exhaust gas composed of water vapor and carbon dioxide is generated by the power generation reaction. Since this power generation reaction is accompanied by heat generation, the generated exhaust gas has a high temperature.

  Although not shown in the figure, each fuel cell 22 has a little more than half of the peripheral surface of the fuel electrode covered with an oxygen electrode through a solid electrolyte layer, and the remaining peripheral surface is covered with an interconnector. The fuel cell 22 has a plurality of fuel cells 22 connected in series by electrically connecting the oxygen electrode and fuel electrode of adjacent fuel cells via an interconnector and a current collecting member. Are in a relationship.

In the fuel cell, the fuel electrode is porous and made of nickel / YSZ cermet (mixed sintered body) containing nickel (Ni) as one component. The solid electrolyte layer is dense and consists of a mixture of yttria (Y ₂ O ₃ ) and zirconia (ZrO ₂ ). The oxygen electrode is porous and made of LSM (La _1-x Sr _x MnO ₃ ), which is a perovskite oxide. The interconnector is made of a conductive ceramic.

  At the upper end of each fuel cell 22, the reformed gas passage 23 is opened, and surplus reformed gas that has not been consumed for power generation, so-called off-gas, is released. A spark electrode (not shown) is disposed in the vicinity of the upper end of each fuel cell 22 and, as shown in FIGS. 1 and 2, when the spark electrode discharges with a spark, the tip of each fuel cell 22 is shown. The off-gas flowing out from the reactor reacts with the surrounding oxygen-containing gas and burns. In other words, in the present embodiment, the upper ends of the plurality of fuel cells 22 serve as an off-gas combustion region that has passed through the fuel cells 22.

  Although not shown, the manifold 30 has a reformed gas flow path inside, and supplies the reformed gas flowing through the manifold 30 on the upper surface to the plurality of reformed gas passages 23 of the plurality of fuel cells 22. For this purpose, a plurality of pores are opened. As shown in FIG. 1, the manifold 30 is connected to a reformer 40 and two reformed gas supply pipes 31. Therefore, the reformed gas generated in the reformer 40 is supplied to the manifold 30 through the reformed gas supply pipe 31 and is equally supplied to the reformed gas passages 23 of the fuel cells 22 through the manifold 30 as shown in FIG. To be supplied.

  As shown in FIG. 1 and FIG. 2, the two common gas supply members 60 supply air as an oxygen-containing gas to a plurality of fuel cells 22 in common. In this power generation device, by providing a common gas supply member 60 that is commonly used for a plurality of fuel cells 22, compared to a case where a gas supply member is provided for each fuel cell 22 individually, Compactness is achieved.

  Each common gas supply member 60 is formed in a hollow flat plate shape whose upper end and side are closed. The common gas supply member 60 is preferably formed of a material having high thermal conductivity. In this embodiment, the common gas supply member 60 is formed of metal, but the material is not particularly limited. As described above, the pair of common gas supply members 60 covers both sides of the fuel cell unit 20 in a state where the reformer 40 and the vaporizer 50 are stacked. That is, each common gas supply member 60 is disposed on the side of the fuel cell unit 20 so as to face the side surface of the fuel cell 22.

  As shown in FIG. 1, the common gas supply member 60 has gas introduction pipes 61 connected to both sides in the lateral direction at the top. In each common gas supply member 60, a long through hole 64 is formed in the lateral direction between the parts where the two gas introduction pipes 61 are connected, and the four branching blocking grooves 65 are provided in the lower part. Is provided. At the lower end of the common gas supply member 60, an opening 66 is formed by opening at a portion where the branching blocking groove 65 is not provided. In the common gas supply member 60, a plurality of obstacles 63 are provided between the portions where the through holes 64 and the branching blocking grooves 65 are provided, that is, in a substantially central region in the vertical direction.

  As shown in FIG. 2, each of the obstacles 63 is configured such that the inner plate 67 is partially formed by the inner plate 67 disposed on the fuel cell unit 20 side of the common gas supply member 60 and the outer plate 68 facing the inner plate 67. It protrudes toward the outer plate 68 and is brought into contact with the outer plate 68. As a result, the surface of the inner plate 67 on the fuel cell 22 side is recessed at the site where the obstacle 63 is formed. The obstruction part 63 only needs to obstruct the flow of the oxygen-containing gas flowing through the passage formed between the inner plate 67 and the outer plate 68. In the obstruction part 63, two plates 67 on the inner side and the outer side are provided. , 68 may be bonded or simply abutted. Further, as shown in FIG. 1, the obstacle 63 has a circular cross section parallel to the outer plate 68. Each obstacle part 63 has four rows in the vertical direction, and is provided with four rows, five rows, four rows, and five rows in the horizontal direction in order from the top row. The distance in the horizontal direction between the obstacles 63 is the same length in any stage, and the distance between the stages arranged vertically is also the same. Therefore, the respective obstacles 63 are provided substantially evenly in this substantially central region of the common gas supply member 60. Each of the diversion blocking grooves 65 is also formed by the inner plate 67 partially protruding toward the outer plate 68 and abutting against the outer plate 68. The four branch flow blocking grooves 65 are intermittently arranged in the lateral direction.

  With such a configuration, as shown by the arrow in FIG. 1, the oxygen-containing gas that has flowed into the common gas supply member 60 through the gas introduction pipe 61 flows from the upper side to the lower side through the common gas supply member 60, and the obstacle 63. In order to change the direction of the flow every time they collide with each other, the oxygen-containing gas flows in a meandering manner in the common gas supply member 60. Then, the oxygen-containing gas is diverted by the diversion blocking groove 65, flows out through the opening 66 at the lower end, and is supplied to each fuel cell 22 of the fuel cell unit 20.

Next, the power generation operation of the power generation unit 10 of the power generation apparatus and the fluid flow during the power generation operation will be described.
When water is supplied to the vaporizer 50 through the water supply pipe 51, the water is vaporized by the combustion heat of the off-gas that has passed through the fuel battery cell in the vaporizer 50 to become water vapor. The reformer 40 is supplied with the steam generated in this manner through the steam supply pipe 52 and the fuel gas through the fuel gas supply pipe 45. In the reformer 40, the steam and the fuel gas are mixed, and the mixed gas is reformed to become a reformed gas, and this reformed gas is sent to the manifold 30 through the reformed gas supply pipe 31. The reformed gas sent to the manifold 30 is sent to the reformed gas passages 23 of the respective fuel cells 22 as indicated by broken line arrows in FIG.

  On the other hand, the oxygen-containing gas flows into the common gas supply member 60 through the gas introduction pipe 61. Here, as shown in FIG. 1, the common gas supply member 60 has a through-hole 64 formed between the gas introduction pipes 61, so that the oxygen content flowing into the common gas supply member 60 through the gas introduction pipe 61 is included. The gas flows from the top to the bottom while the lateral diffusion is restricted. Since a plurality of obstacles 63 are formed in the common gas supply member 60, the oxygen-containing gas passes through the passages in the common gas supply member 60 as shown in FIG. Every time it collides, it changes the direction of flow and meanders. As a result, in this embodiment, the path through which the oxygen-containing gas flows becomes longer, so the flow velocity becomes faster and the flow becomes turbulent. In addition, a multi-directional flow of oxygen-containing gas occurs. Therefore, in this embodiment, the opportunity for the oxygen-containing gas to come into contact with the inner plate 67 is increased as compared with a configuration in which no obstacle is provided. Then, the oxygen-containing gas is diverted by the diversion blocking groove 65 and flows out from the opening 66, and is evenly supplied to each fuel cell 22 in the fuel cell unit 20.

  As shown in FIG. 2, in the fuel cell unit 20, the reformed gas flows through the reformed gas passage 23 from the lower side to the upper side of the fuel cell 22. On the other hand, the oxygen-containing gas flows from the lower side to the upper side on the outer side of the fuel cell 22 and is supplied to the oxygen electrode of the fuel cell. The fuel cell 22 generates power by reacting the reformed gas flowing inside with the oxygen-containing gas flowing around. Moreover, since this electric power generation is an exothermic reaction as mentioned above, the fuel cell 22 becomes high temperature. Thereby, as shown by the chain line arrow in FIG. 2, the inner plate 67 of the common gas supply member 60 is heated by the radiant heat and conduction heat from the fuel cell 22. Here, as described above, since the oxygen-containing gas flowing inside the common gas supply member 60 has many opportunities to come into contact with the inner plate 67 by the obstacle 63, the inner plate 67 and the oxygen-containing gas Heat exchange takes place actively. Therefore, more heat generated by the power generation of the fuel cell 22 can be supplied to the oxygen-containing gas, and the oxygen-containing gas is appropriately heated. Further, in the present embodiment, the inner plate 67 is recessed toward the outer plate 68 at the site where the obstacle 63 is formed, so that the heat transfer area is increased as compared with the case where the inner plate 67 is formed flat. The inner plate 67 can absorb more conduction heat from the fuel cell. Therefore, the oxygen-containing gas can be heated more appropriately also by this.

  At the upper end portion of the fuel cell 22, the off gas that has passed through the fuel cell 22 reacts with the surrounding oxygen-containing gas by the spark discharge of the spark electrode and burns. The lower portion of the reformer 40 is directly heated by the combustion heat of the off gas, and the heat generated by the combustion is heated by flowing through the exhaust gas holes 48. Further, the high-temperature exhaust gas generated by the off-gas combustion is sent to the vaporizer 50 disposed on the upper side of the reformer 40 through the exhaust gas hole 48 of the reformer 40 as shown by the solid thick arrow in FIG. It is used for heating water in the vaporizer 50. Thus, in this embodiment, the combustion heat of off-gas is used as a heat source for both the reforming reaction in the reformer 40 and the vaporization of water in the vaporizer 50.

  The exhaust gas further flows between the vaporizer 50 and the two common gas supply members 60. Thereby, the oxygen containing gas which flows through the upper part of the common gas supply member 60 is heated by exchanging heat with the exhaust gas. As shown in FIG. 1, in the upper part of the common gas supply member 60, after the oxygen-containing gas flows in through the gas introduction pipes 61 on both sides, the diffusion in the lateral direction is restricted by the through-holes 64. Flowing. On the other hand, in the carburetor 50, the width of the portion in the vicinity of both end portions in the lateral direction is narrower than that of the other portions, so that the exhaust gas flowing upward through the exhaust gas hole 48 of the reformer 40 is on the carburetor 50 side. A large amount flows in the vicinity of both ends of the direction. Therefore, a large amount of exhaust gas flows in the vicinity of the portion where the oxygen-containing gas flows in the upper part of the common gas supply member 60, so that heat exchange between the oxygen-containing gas and the exhaust gas is performed efficiently.

  As described above, the oxygen-containing gas is heated by the exhaust gas when flowing through the upper portion of the common gas supply member 60, and meanders when flowing through the region where the obstruction part 63 is formed. It absorbs more heat of 22 and is heated. Therefore, in this embodiment, the oxygen-containing gas can be appropriately heated, and it is possible to suppress a decrease in power generation efficiency in the power generation apparatus.

  Table 1 shows the power generation apparatus in the present embodiment and the example shown in FIG. 4 devised by the inventors of the present application, and the exhaust gas generated by the combustion of the off-gas of the fuel cell and the fuel cell and the oxygen containing gas flowing through the common gas supply member The simulation result of the heat exchange amount with gas is shown.

  As shown in Table 1, the heat exchange amount is 178 W in the present embodiment in which the common gas supply member 60 includes a plurality of obstacles 63, and the heat exchange amount is 108 W in the configuration shown in FIG. 4 without the obstacles. . As described above, in this embodiment, the common gas supply member 60 includes the plurality of obstacles 63, so that the heat exchange amount is improved by about 70% as compared with the configuration without the obstacles. By causing the oxygen-containing gas to meander in 60, the oxygen-containing gas can be appropriately heated.

  A power generator according to Example 2 will be described with reference to FIG. As shown in FIG. 3, Example 2 is different from Example 1 in the configuration of the common gas supply member 70. In addition, since the other structure is the same as Example 1, it shows using the same code | symbol and the description is abbreviate | omitted.

  As shown in FIG. 3, in the common gas supply member 70 of the power generation unit 11 of the present embodiment, the portion corresponding to the downstream side of the flow of the reformed gas and the oxygen-containing gas in the fuel battery cell 22 snakes around the oxygen-containing gas. The obstacle part 73 is provided so that the degree becomes large. Also in this embodiment, the obstacle 73 is such that the inner plate 77 disposed on the fuel cell unit 20 side of the common gas supply member 60 protrudes toward the outer plate 78 and the plates 77 and 78 come into contact with each other. It is formed by.

  Each obstacle 73 has three stages in the vertical direction, and is arranged in five rows, four rows, and three rows in the horizontal direction in order from the top, and the number of obstacles 73 arranged in the horizontal direction is as low as the bottom. It is running low. Further, the horizontal interval between the obstacles 63 is narrowed toward the top. In addition, the interval between the upper and lower stages is such that the distance between the uppermost stage and the middle stage is smaller than the distance between the middle stage and the lowermost stage. In the present embodiment, instead of providing the plurality of obstacle portions 63 substantially equally in the first embodiment, the plurality of obstacle portions 73 are densely arranged above the lower portion of the common gas supply member 70, thereby allowing the fuel cell unit. The portion corresponding to the downstream side of the gas flow at 22 (the upper portion of the common gas supply member 70) is increased in the meandering degree of the oxygen-containing gas.

  Here, in the fuel cell 22, the reformed gas and the oxygen-containing gas react to generate electricity and generate heat. As described with reference to FIG. 2 in the first embodiment, the reformed gas and the oxygen-containing gas are contained. Gas flows from the bottom to the top. The high-temperature exhaust gas generated by the power generation flows upward, and the gas used for power generation gradually flows upward while being heated by the heat generation. Tends to be hot.

  In this regard, in the common gas supply member 70, as described above, the obstacle portion 73 is provided so that the degree of meandering of the oxygen-containing gas increases toward the top. Therefore, in the common gas supply member 70, heat exchange between the inner plate 77 and the oxygen-containing gas is more actively performed corresponding to the upper portion of the fuel cell 22 that tends to be high temperature, and the inner plate 77 is removed from the fuel cell 22. The absorbed heat is easily released by the oxygen-containing gas. Therefore, the upper side of the common gas supply member 70 allows the inner plate 77 to transfer more and more heat from the fuel cell 22, and the amount of heat released from the upper side of the fuel cell 22 is increased. On the other hand, in the common gas supply member 70, the heat exchange between the inner plate 77 and the oxygen-containing gas is not performed as actively as the upper part corresponding to the lower part where the fuel battery cell 22 is not so hot. The lower part of the heat dissipation is less than the upper part.

  As described above, in this embodiment, the portion of the fuel cell 22 that tends to have a higher temperature can increase the heat radiation amount. Therefore, the temperature gradient generated in the fuel cell 22 is corrected and the temperature of the entire fuel cell 22 is reduced. Uniformity can be achieved. Therefore, this part deteriorates due to the fuel cell 22 partially becoming too hot, or the power generation efficiency at this part is caused by the fuel cell 22 partially becoming too low. It can suppress that it falls.

  In addition, since the flow of oxygen-containing gas in the common gas supply member 70 and the flow of gas used for power generation in the fuel battery cell 22 are in opposite directions, the fuel battery cell 22 has a higher temperature at the top, In the common gas supply member 60, the temperature is lower at the upper part. Accordingly, the temperature difference between the oxygen-containing gas flowing in the upper part of the common gas supply member 60 and the upper part of the fuel cell 22 is larger than the temperature difference in the lower part. More heat can be supplied to the oxygen-containing gas.

Also in this embodiment, the oxygen-containing gas is heated by the exhaust gas when flowing through the upper part of the common gas supply member 70 and flows meandering when flowing through the region where the obstacle 73 is formed. The cell 22 is heated by absorbing more heat. As described above, in this embodiment, the power generation efficiency of the power generation apparatus can be improved by appropriately heating the oxygen-containing gas as compared with the case where the common gas supply member having no obstacle is used. Therefore, it can suppress that power generation efficiency falls, achieving compactness.
(Other examples)

  In each of the above embodiments, the reformer and the vaporizer are arranged in this order on the fuel cell unit. However, the vaporizer and the reformer may be arranged in this order on the fuel cell unit. Further, without disposing these members on the fuel cell unit in this way, the combustion heat of the off gas may be used for heating these members. Further, the power generation device may have a structure in which the reformed gas and the oxygen-containing gas are supplied to the fuel battery cell, and it is not necessary to generate the reformed gas by the vaporizer and the reformer. It may be a thing which does not have. The oxygen-containing gas may be oxygen as long as it contains oxygen.

  In each of the above-described embodiments, the common gas supply member is formed in a flat plate shape. However, the common gas supply member and the overhanging portion that protrudes above the fuel cell from the upper end of the flat plate member. The oxygen-containing gas flowing through the overhanging portion is heated by the exhaust gas flowing upward from the vaporizer shown in FIG. 2 by allowing the oxygen-containing gas to flow through the overhanging portion and the plate-shaped member. You may make it do. In each of the above embodiments, in the common gas supply member, the oxygen-containing gas is first heated by the off-gas exhaust gas and then heated by the heat generated by the power generation of the fuel cell. You may make it heat only with the heat | fever of the electric power generation of a fuel cell, without heating with waste gas. Further, in each of the above embodiments, the flow-off flow of the oxygen-containing gas is controlled by providing the common gas supply member with a closed groove or through-hole for diversion. It is good also as a simple structure which does not provide a hole.

  In each of the above embodiments, the cross-sectional shape of the obstacle portion is circular, but the shape of the obstacle portion is not particularly limited. Further, in each of the above embodiments, the inner plate is protruded toward the outer plate to form an obstruction, and the surface of the inner plate facing the fuel cell side is recessed at the portion where the obstruction is formed. However, the inner plate may be formed flat at the site where the obstacle is provided, and the outer plate may be recessed toward the inner plate. Moreover, you may make it adjoin by projecting so that both an inner side board and an outer side board may mutually approach. Moreover, you may make it adjoin these plates by interposing a member between both plates, without making both an inner side board and an outer side board protrude. Further, the inner plate and the outer plate may not be in contact with each other at the obstacle portion, and a part of the inner plate and the outer plate may be adjacent to each other with a minute gap therebetween.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  In addition, the technical elements described in the present specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

10, 11, 110: power generation unit 20, 120: fuel cell unit 22, 122: fuel cell 23: reformed gas passage 30: manifold 31: reformed gas supply pipe 40, 140: reformer 45: fuel gas supply Pipe 48: Exhaust gas hole 50, 150: Vaporizer 51: Water supply pipe 52: Water vapor supply pipe 60, 70, 160: Common gas supply member 61, 161: Gas introduction pipe 63, 73: Obstacle 64: Through hole 65: Blocking grooves 66, 166 for diversion: openings 67, 77: inner plates 68, 78: outer plates

Claims (2)

A fuel cell unit in which a plurality of fuel cells are erected in parallel;
Supplying a gas containing oxygen to the plurality of fuel cells, and a common gas supply member disposed on a side of the fuel cell unit so as to face a side surface of the plurality of fuel cells. Has
Each of the plurality of fuel cells is a solid oxide fuel cell having a columnar shape and having a reformed gas passage penetrating in the axial direction,
The common gas supply member is made of a thermally conductive material and is disposed on the fuel cell unit side, an outer plate facing the inner plate, the inner plate and the outer plate across a plurality of rows and rows. that some than other parts partially meandering oxygen-containing gas by proximity to an obstacle to the flow of oxygen-containing gas, and a plurality of obstruction that cause turbulence A featured power generator. Wherein in the common gas supply member according to claim, characterized in that as the portion corresponding to the downstream side of the flow of the reformed gas, the previous SL multiple failures portions are provided densely in the plurality of fuel cells 1 The power generator described in 1.

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