JP2019175640A - Fuel cell system - Google Patents

Abstract

To provide a fuel cell system capable of simplifying structure of a hot-water storage apparatus and capable of reducing manufacturing cost.SOLUTION: A fuel cell system includes: a fuel cell body 2 for performing power generation by fuel cell reaction; a hot water storage apparatus 6 for recovering waste heat of the fuel cell body 2 as hot water; and an accommodation housing 8 for accommodating the fuel cell body 2 and the hot water storage apparatus 6. A suction port 74 and an exhaust port 78 are formed in the accommodation housing 8. A ventilation fan 80 is arranged in relation to the exhaust port 78. The hot water storage apparatus 6 includes: a hot water storage tank 56; heat exchangers 60, 62 for performing heat exchange with water from the hot water tank; a radiator 66 arranged on the upstream side of the heat exchanger 60; and a heat recovery circulation passage 58 for circulating water in the hot water tank 56 through the radiator 66 and the heat exchangers 60, 62. The radiator 66 is arranged on the inside of the suction port 74 of the accommodation housing 8.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a fuel cell system including a fuel cell main body that generates power and a hot water storage device that recovers exhaust heat from the fuel cell main body as hot water.

  2. Description of the Related Art As a fuel cell system, a fuel cell system including a fuel cell main body that generates power and a hot water storage device that stores exhaust heat from the fuel cell main body as hot water is known (for example, see Patent Document 1). In such a fuel cell system, a cooling water circulation passage is provided in the fuel cell main body, and the cooling water is circulated through the cooling water circulation passage. The hot water storage device includes a hot water storage tank for storing hot water and a heat recovery circulation channel for circulating water from the hot water storage tank, and a heat exchanger is disposed in the heat recovery circulation channel. . Furthermore, a bypass flow path is provided by bypassing a part of the heat recovery circulation flow path, a radiator is provided in the bypass flow path, and a three-way valve is provided at a connection portion between the bypass flow path and the heat recovery circulation flow path. Is arranged.

  In such a fuel cell system, normally, water from the hot water storage tank is circulated through the heat recovery circulation channel and the heat exchanger, and the water flowing through the heat recovery circulation channel and the cooling water circulation channel in this heat exchanger. Heat is exchanged with the cooling water, and the water heated by this heat exchange is stored in the hot water storage tank through the heat recovery circulation channel. When the hot water storage tank is filled with hot water, the three-way valve is switched so that the heat recovery circulation channel and the bypass channel are communicated, and hot water from the hot water storage tank flows through the bypass channel and the radiator. The hot water (water) whose temperature has decreased is supplied to the heat exchanger, and heat exchange is performed between the hot water whose temperature has decreased in the heat exchanger and the cooling water flowing through the cooling water circulation passage.

JP 2004-296267 A

  However, the fuel cell system described above has the following problems. First, since a three-way valve and a bypass flow path for switching the flow of water (hot water) flowing from the hot water storage tank to the heat exchanger are required, the configuration becomes complicated and becomes a cause of malfunction. There is a problem that the manufacturing cost is also increased.

  Secondly, in such a fuel cell system, the fuel cell main body, the hot water storage device and the like are accommodated in the accommodating housing. In this case, in order to prevent the inside of the accommodating housing from becoming a high temperature, a ventilation port is provided in the accommodating housing. In addition to the radiator fan installed in the radiator, a ventilation fan is required, and the structure is complicated and the manufacturing cost is increased. There is a problem that becomes high.

  The objective of this invention is providing the fuel cell system which can aim at the simplification of the structure in connection with a hot water storage apparatus, and can aim at reduction of manufacturing cost.

The fuel cell system according to claim 1 of the present invention includes a fuel cell main body that generates power by a fuel cell reaction at a fuel electrode and an oxygen electrode, a hot water storage device that recovers exhaust heat of the fuel cell main body as hot water, and the fuel A fuel cell system comprising a battery body and a housing for housing the hot water storage device,
The storage housing is provided with an intake port for sucking outside air into the storage housing, and an exhaust port for discharging the air inside the storage housing to the outside. Relatedly, a ventilation fan for ventilating the air in the housing is provided,
The hot water storage device includes a hot water storage tank for storing hot water, a heat exchanger for exchanging heat between the cooling water and / or exhaust gas flowing from the fuel cell main body and the water flowing from the hot water storage tank. A radiator disposed on the upstream side of the heat exchanger, and a heat recovery circulation passage for circulating water in the hot water storage tank through the radiator and the heat exchanger, the radiator containing the housing It is arrange | positioned inside the said inlet port of a housing, It is characterized by the above-mentioned.

  In the fuel cell system according to claim 2 of the present invention, a temperature maintenance heater for maintaining the temperature in the housing is disposed in the vicinity of the intake port, or in the radiator or in the vicinity thereof. It is characterized by.

  Furthermore, in the fuel cell system according to claim 3 of the present invention, the intake port is provided at a lower portion or an upper portion of one side wall of the housing housing, and the exhaust port faces the one side wall of the housing housing. It is provided in the upper part or the lower part of the other side wall, and the air flowing in from the intake port flows obliquely in the housing housing toward the exhaust port.

  According to the fuel cell system of the first aspect of the present invention, the housing housing is provided with the intake port and the exhaust port, and the ventilation fan is provided in association with the exhaust port. The hot water storage device includes a hot water storage tank for storing hot water, a heat exchanger for exchanging heat between the water from the hot water storage tank, a radiator disposed upstream of the heat exchanger, and a hot water storage tank. And a heat recovery circulation channel for circulating water, and the water from the hot water storage tank is circulated through the radiator and the heat exchanger, so that water (hot water) is selectively passed through the radiator. Therefore, the manufacturing cost can be reduced by simplifying the configuration related to the hot water storage device without requiring a three-way valve and a bypass flow path. In addition, since this radiator is disposed inside the intake port of the housing housing and the radiator is cooled by the air flow through the intake port by the ventilation fan, a radiator fan or the like is not necessary, and in this connection In addition, the configuration related to the hot water storage apparatus can be simplified and the manufacturing cost can be reduced.

  In the fuel cell system according to claim 2 of the present invention, the temperature maintaining heater is disposed in the vicinity of the intake port (or the radiator or the vicinity thereof). Even when the inside of the housing is ventilated by operating the ventilation fan when the temperature is low, it is possible to prevent freezing in the radiator and the vicinity thereof by operating the heater for maintaining the temperature. Further, since heating is performed using a temperature maintaining heater for maintaining the temperature in the housing, it is not necessary to provide a dedicated heater for preventing freezing, and the configuration is simplified in this connection. The manufacturing cost can be reduced.

  Furthermore, according to the fuel cell system of the third aspect of the present invention, the intake port is provided in the lower part (or upper part) of one side wall of the housing housing, and the exhaust port is the upper part (or lower part) of the other side wall of the housing housing. The air that has flowed in from the air intake vent passes through the radiator, flows diagonally through the housing, and is discharged from the exhaust vent by the action of the ventilation fan. Ventilation in the housing and cooling of the radiator can be performed.

1 is a simplified diagram showing an entire embodiment of a fuel cell system according to the present invention. The figure for demonstrating the driving | running state when the hot water storage tank is filled with warm water in the fuel cell system of FIG.

  Hereinafter, an embodiment of a fuel cell system according to the present invention will be described with reference to the accompanying drawings. In FIG. 1, the illustrated fuel cell system includes a fuel cell main body 2, a reformer 4, and a hot water storage device 6, and the fuel cell main body 2, the reformer 4, and the hot water storage device 6 are contained in a box-shaped housing housing 8. Contained as required. The fuel cell body 2 includes a fuel electrode 10 and an air electrode 12, and generates power by a fuel cell reaction (so-called electrochemical reaction) by oxidation and reduction of the fuel electrode 10 and the air electrode 12. Such a fuel cell main body 2 may be a solid polymer type (PEFC) using a polymer electrolyte membrane as an electrolyte, or an ion conductive ceramic (SOFC) using an electrolyte.

  An introduction side of the fuel electrode 10 of the fuel cell main body 2 is connected to the reformer 4 via a reformed gas supply channel 14, and the reformer 4 is connected to the fuel via a fuel gas supply channel 16. It is connected to a fuel gas supply source (not shown) for supplying gas. Examples of the fuel gas supply source include a buried pipe, a storage tank, and the like. For example, city gas as fuel gas is supplied from the fuel gas supply source. The fuel gas supply channel 16 is provided with a fuel supply pump 18 for supplying the fuel gas toward the reformer 4, and the fuel gas is supplied to the upstream side of the fuel supply pump 18. A fuel on / off valve 20 for stopping supply is provided.

  The reformer 4 also includes a steam generation unit 22 for vaporizing the reformed water and a reforming unit 24 for reforming the fuel gas. The reformer 24 converts the fuel gas into steam reformer. A reforming catalyst (not shown) for charging is filled. A fuel gas supply channel 16 is connected to the water vapor generating section 22 of the reformer 4, and a reformed gas supply channel 14 is connected to the reforming section 24. Further, the water vapor generation unit 22 of the reformer 4 is connected to a water tank 28 via a water supply channel 26, and a water supply pump for supplying reformed water to the reformer 4 through the water supply channel 28. 30 is disposed.

  Since it is configured in this way, the reformed water in the water tank 28 is supplied to the water vapor generation part 22 of the reformer 4 through the water supply flow path 26 by the water supply pump 30, and in this water vapor generation part 22 Vaporized into steam. In addition, fuel gas from a fuel gas supply source (not shown) is supplied to the water vapor generation part 22 of the reformer 4 through the fuel gas supply flow path 16 by the fuel supply pump 18. The mixed gas is supplied to the reforming unit 24. In the reforming unit 24 of the reformer 4, the fuel gas is steam reformed, and the steam reformed reformed gas is fed to the fuel electrode 10 side of the fuel cell body 2 through the reformed gas feed channel 14. The

  The introduction side of the air electrode 12 of the fuel gas main body 2 is connected to an air blower 34 via an air supply passage 32. A suction port 38 is provided at a predetermined portion of the housing 8, for example, at an upper portion of the one side wall 36, corresponding to the location of the air blower 34. With this configuration, the external air is sucked through the suction port 38 of the housing 8 by the air blower 34 and then supplied to the air electrode 12 side of the fuel cell main body 2 through the air supply channel 32. .

  The reformed gas is supplied to the fuel electrode 10 side of the fuel cell body 2 as described above, and the air is supplied to the air electrode 12 side as described above. Power generation is performed by a fuel cell reaction (so-called electrochemical reaction) by oxidation and reduction of the electrode 10 and the air electrode 12.

  The reaction fuel gas from the fuel electrode 10 of the fuel cell main body 2 is discharged into the atmosphere through the reaction gas discharge channel 40. Further, the reaction air from the air electrode 12 is discharged into the atmosphere through the reaction air discharge channel 42. In this specification, “exhaust gas” is used as a concept including reaction fuel gas and reaction air.

  In this fuel cell system, a cooling means 46 for cooling the fuel cell main body 2 is provided. The cooling means 46 includes a cooling water tank 48 that contains cooling water, and a cooling water circulation passage 52 for circulating the cooling water in the cooling water tank 48 through the cooling unit 50 of the fuel cell main body 2. A cooling water circulation pump 54 is disposed in the passage 52. With this configuration, the cooling water in the cooling water tank 48 is circulated through the cooling water circulation passage 52 by the cooling water circulation pump 54, and the cooling water 50 is circulated so that the cooling unit 50 of the fuel cell main body 2 is circulated. To be cooled.

  The hot water storage device 6 includes a hot water storage tank 56 for storing hot water, and a heat recovery circulation channel 58 for recovering heat by circulating water (hot water) in the hot water storage tank 56. A first heat exchanger 60 and a second heat exchanger 62 are disposed, and further, a water circulation pump 64 for supplying water (hot water) in the hot water storage tank 56, a heat recovery on-off valve 65, and a radiator 66 are disposed. ing. The first heat exchanger 60 is provided in association with the cooling means 46, and exchanges heat between water (hot water) flowing through the heat recovery circulation channel 58 and cooling water flowing through the cooling water circulation channel 52. The second heat exchanger 62 is provided in association with the discharge side of the fuel cell body 2, and the reaction fuel gas flowing through the reaction gas discharge channel 40 and the reaction air (exhaust gas) flowing through the reaction air discharge channel 42. And water (hot water) flowing through the heat recovery circulation channel 58 are exchanged. The radiator 66 cools water (hot water) flowing through the heat recovery circulation channel 58 as described later, and the heat recovery on / off valve 65 supplies and stops the supply of water (hot water) from the hot water storage tank 56.

  At the bottom of the hot water storage tank 56, for example, a water supply channel 68 for supplying tap water is provided, and a supply opening / closing valve 70 is provided in the water supply channel 68. Further, a hot water flow path 72 is connected to the upper end portion of the hot water storage tank 56, and hot water in the hot water storage tank 56 is discharged through the hot water flow path 72.

  With this configuration, the water (hot water) in the hot water storage tank 56 is circulated through the heat recovery circulation channel 58, the radiator 66, the first heat exchanger 60, and the second heat exchanger 62 by the water circulation pump 64. The reaction fuel gas heated by the heat exchange with the cooling water flowing through the cooling water circulation passage 52 in the first heat exchanger 60 and flowing through the reaction gas discharge passage 40 in the second heat exchanger 62 The hot water heated by the heat exchange with the reaction air flowing through the reaction air discharge channel 42 is stored in the hot water storage tank 56. The water contained in the reaction fuel gas and the reaction air (exhaust gas) is condensed by heat exchange in the second heat exchanger 62, and the condensed water thus condensed is recovered in the water tank 28 through the water recovery passage 73. The condensed water thus recovered is used as reforming water.

  This fuel cell system is further configured as follows. In this embodiment, an air inlet 74 is provided in the lower part of the one side wall 36 of the housing 8, and a radiator 66 is disposed inside the air inlet 74. In addition, an exhaust port 78 is provided in the upper portion of the other side wall 76 facing the one side wall 36 of the housing 8, and in relation to the exhaust port 78, a ventilation fan 80 is disposed inside the exhaust port 78. .

  With this configuration, when the temperature in the housing 8 rises and air ventilation is required, the ventilation fan 80 is activated to ventilate the housing 8. Referring also to FIG. 2, when the ventilation fan 80 is operated, the air in the housing housing 8 is discharged to the outside through the exhaust port 78 as indicated by the arrow 82, and accordingly, the intake port 74 is indicated as indicated by the arrow 84. Outside air is introduced through. Then, the air introduced through the intake port 74 flows obliquely upward toward the exhaust port 74 as indicated by a broken line arrow in FIG. 2, and the inside of the housing 8 is ventilated and cooled as required by the flowing air flow, For example, the control devices 85 (control boards) built in the housing 8 are cooled.

  In this embodiment, a temperature maintaining heater 86 for maintaining the temperature of the housing 8 is further provided, and the temperature maintaining heater 86 is provided in the vicinity of the intake port 74 (in the illustrated form, the housing housing 8 It is disposed on the inner side of the one side wall 36 below the intake port 74. Therefore, when the temperature inside the housing 8 is low, the temperature maintaining heater 86 is energized, and the inside of the housing 8 is warmed by the heat from the temperature maintaining heater 86. The temperature maintaining heater 86 may be directly attached to the radiator 66 or may be disposed in the vicinity of the radiator 66 for the reason described later.

  In this fuel cell system, when the hot water tank 56 is filled with hot water, exhaust heat is recovered after the temperature of the hot water flowing from the hot water tank 56 to the first heat exchanger 60 is lowered. . That is, at this time, the ventilation fan 80 is operated to ventilate the housing housing 8, and air from the intake port 74 flows downstream through the periphery of the radiator 66 during this ventilation. Accordingly, when the hot water from the hot water storage tank 56 flows through the radiator 66, it is cooled by the air flowing in from the intake port 74, and the hot water whose temperature has been lowered in this way is the heat recovery circulation channel 58, the first heat exchanger 60. And through the second heat exchanger 52. Therefore, the above-described heat exchange in the first heat exchanger 60 is possible, and the above-described heat exchange in the second heat exchanger 62 is possible. Even when the hot water storage tank 56 is full of hot water, the fuel cell Recovery of exhaust heat from the main body 2 can be performed as required.

  In such an exhaust heat recovery operation, the temperature of the hot water flowing through the radiator 66 (that is, the hot water from the hot water storage tank 56) is lowered by the air flow generated by the operation of the ventilation fan 80, so that it is provided in the conventional radiator. Further, the radiator fan can be omitted, and the configuration related to the hot water storage device 6 can be simplified and the manufacturing cost can be reduced. Further, in such an arrangement connection structure of the radiator 66, it is not necessary to bypass the heat recovery circulation channel 58 and provide a bypass channel, and further, a three-way valve for selectively switching the channel is not required, Also by this, the structure relevant to the hot water storage apparatus 6 can be simplified and the manufacturing cost can be reduced. In addition, since the radiator 66 is disposed inside the intake port 74 of the housing 8, the radiator 66 can be effectively cooled by the air flow flowing through the intake port 74.

  In addition, when the outside of the housing 8 is ventilated by operating the ventilation fan 80 when the outside air is cold, such as in winter, the radiator 66 is supercooled by the air flow flowing through the intake port 74 of the housing 8, and this overcooling causes There is a possibility that water from the hot water storage tank 56 is frozen by the radiator 66. In such a case, the temperature maintaining heater 86 is actuated, and the radiator 66 is heated by the heat from the temperature maintaining heater 86. By controlling in this way, the water flowing through the radiator 66 is frozen. Can be prevented. In such a configuration, the temperature maintaining heater 86 for maintaining the temperature in the housing 8 is used to prevent freezing in the radiator 66, so there is no need to provide a dedicated antifreezing heater. Even in this case, the configuration can be simplified and the manufacturing cost can be reduced.

  As mentioned above, although one embodiment of the fuel cell system according to the present invention has been described, the present invention is not limited to such an embodiment, and various changes or modifications can be made without departing from the scope of the present invention.

  For example, in the above-described embodiment, the first heat exchanger 60 performs heat exchange with the cooling water of the fuel cell main body 2 to recover the exhaust heat, and the second heat exchanger 62 performs the fuel cell main body. Exhaust heat is recovered by exchanging heat between the reaction fuel gas 2 and reaction air (exhaust gas). One of these exhaust heats, that is, exhaust heat from the cooling water or reaction fuel gas and reaction. Exhaust heat from air (exhaust gas) (reactive fuel gas or exhaust heat from reaction air may be used as exhaust gas) may be recovered.

  Further, for example, in the above-described embodiment, for example, city gas is used as the fuel gas. Therefore, the intake port 74 is provided in the lower part of the one side wall 36 of the housing housing 8, and the exhaust port 78 is provided in the upper part of the other side wall 76. However, when LP gas is used as the fuel gas, for example, an intake port 74 is provided on the upper side of the one side wall 36 of the housing housing 8, and an exhaust port 78 is provided on the lower side of the other side wall 76.

  Further, for example, in the above-described embodiment, the hot water storage tank 56 of the hot water storage device 6 is accommodated in the accommodating housing 8, but a hot water storage housing (not shown) is provided separately from the accommodating housing 8 that accommodates the fuel cell main body 2. The hot water storage tank 56 of the hot water storage device 6 may be accommodated in the hot water storage housing.

2 Fuel Cell Body 4 Reformer 6 Hot Water Storage Device 8 Housing Housing 56 Hot Water Storage Tank 58 Heat Recovery Circulation Channel 60, 62 Heat Exchanger 66 Radiator 74 Intake Port 76 Exhaust Port 80 Ventilation Fan 86 Heating Heater

Claims (3)

A fuel cell main body that generates power by a fuel cell reaction at the fuel electrode and the oxygen electrode; a hot water storage device that recovers exhaust heat from the fuel cell main body as hot water; and a housing that houses the fuel cell main body and the hot water storage device. A fuel cell system comprising:
The storage housing is provided with an intake port for sucking outside air into the storage housing, and an exhaust port for discharging the air inside the storage housing to the outside. Relatedly, a ventilation fan for ventilating the air in the housing is provided,
The hot water storage device includes a hot water storage tank for storing hot water, a heat exchanger for exchanging heat between the cooling water and / or exhaust gas flowing from the fuel cell main body and the water flowing from the hot water storage tank. A radiator disposed on the upstream side of the heat exchanger, and a heat recovery circulation passage for circulating water in the hot water storage tank through the radiator and the heat exchanger, the radiator containing the housing A fuel cell system, wherein the fuel cell system is disposed inside the intake port of a housing.   2. The fuel cell system according to claim 1, wherein a heater for maintaining a temperature for maintaining a temperature in the housing is disposed in the vicinity of the intake port or in the radiator or in the vicinity thereof. . The intake port is provided at a lower portion or an upper portion of one side wall of the housing housing, and the exhaust port is provided at an upper portion or a lower portion of the other side wall facing the one side wall of the housing housing, and flows from the intake port. 3. The fuel cell system according to claim 1, wherein air flows obliquely inside the housing housing toward the exhaust port. 4.

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