JP2006228481A - Exhaust heat processing system for fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust heat processing system 30 capable of supplying another power source needed to an equipment using an air-cooled exhaust heat processing device 6 for processing exhaust heat generated in a fuel cell system power generating system 1 while avoiding difficulties accompanying a stable supply of power by a solar cell to a fuel cell main body, a direct use for control of the fuel cell main body or a direct use for an auxiliary machine concerning reaction of the fuel cell main body, or the like, in a trial for using the fuel cell and the solar cell together. <P>SOLUTION: A solar cell generating device is not used for reaction gas cooling water for an auxiliary power source and a control power source of the fuel cell power generating system 1, but exclusively for air-cooled exhaust heat processing device 6 as an accessory equipment for cooling exhaust heat generated from the fuel cell. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel cell waste heat treatment system for treating waste heat generated in a fuel cell power generation system with a waste heat treatment apparatus.

  Fuel cells such as a phosphoric acid fuel cell (PAFC) and a polymer electrolyte fuel cell (polymer electrolyte fuel cell: PEFC) generate heat when generating electricity. For this reason, it is necessary to cool the heat generation (exhaust heat) in the power generation of the fuel cell, and an exhaust heat treatment apparatus exists as an apparatus therefor.

  There are the following cooling water systems cooled by the exhaust heat treatment device in the fuel cell power generation system. A battery cooling water system that cools the heat generated by the electrode reaction to control the temperature of the fuel cell body, a reformer that reforms a fuel gas such as city gas into a hydrogen-rich gas, and cools the exhaust gas after combustion to water There is an exhaust gas cooling water system for recovery. These cooling water systems are cooled by an external air-cooled exhaust heat treatment apparatus via a heat exchanger.

  FIG. 2 shows an air-cooled exhaust heat treatment apparatus 6 in the conventional fuel cell power generation system 1. In FIG. 2, reference numeral 1 is a fuel cell power generation system, 2 is a high-temperature water heat exchanger for high-temperature water from a battery cooling water system (not shown), 4a is a high-temperature water circulation pump for circulating high-temperature water, and 8 is an air-cooling type. A cooler for high temperature water in the exhaust heat treatment apparatus 6, 5a is a flow control valve for high temperature water, 3 is a low temperature water heat exchanger for low temperature water from an exhaust gas cooling water system (not shown), and 4b is for circulating low temperature water. , A low-temperature water cooler 9 in the air-cooled exhaust heat treatment apparatus 6, a low-temperature water flow control valve 5 b, 7 an air-cooled cooling fan, and 10 a cooling fan motor.

  As shown in FIG. 2, the exhaust heat of the high-temperature water from the battery cooling water system is recovered by the high-temperature water heat exchanger 2 and sent to the cooler 8 for high-temperature water in the air-cooled exhaust heat treatment apparatus 6 by the high-temperature water circulation pump 4a. Is done. Subsequently, after being cooled by the air-cooling type cooling fan 7 rotated by the cooling fan motor 10, it is returned to the high-temperature water heat exchanger 2 via the high-temperature water flow control valve 5a. Similarly, the exhaust heat of the low-temperature water from the exhaust gas cooling water system is recovered by the low-temperature water heat exchanger 3 and sent to the cooler 9 for low-temperature water in the air-cooled exhaust heat treatment apparatus 6 by the low-temperature water circulation pump 4b. Subsequently, after being cooled by the air cooling type cooling fan 7 rotated by the cooling fan motor 10, it is returned to the low temperature water heat exchanger 3 via the low temperature water flow control valve 5b. As described above, the exhaust heat of two kinds of temperatures, that is, the exhaust heat of the high-temperature water in the battery cooling water system and the exhaust heat of the low-temperature water in the exhaust gas cooling system, is cooled by the air-cooling cooling fan 7 of the air-cooling exhaust heat treatment apparatus 6. Then, it is returned to the high temperature water heat exchanger 2 or the low temperature water heat exchanger 3 again and used as a cooling medium for the high temperature water heat exchanger 2 or the low temperature water heat exchanger 3.

  In order to operate the above-described air-cooled exhaust heat treatment apparatus 6, the high-temperature water circulation pump 4a and the low-temperature water circulation pump 4b, the cooling fan motor 10, the air-cooling cooling fan 7, the high-temperature water flow control valve 5a and the low-temperature water are used as the equipment used. It is necessary to supply power as a power source for the control flow rate control valve 5b, the air-cooled exhaust heat treatment apparatus 6 as a whole, a freeze prevention heater and the like.

  For example, the equipment required for the air-cooled exhaust heat treatment device 6 of the PAFC 100 KW power generation device includes two 0.5 to 1.5 KW circulation pumps (a high-temperature water circulation pump 4a and a low-temperature water circulation pump 4b), and a 0.5 KW air-cooling type. There are five cooling fans 7, a 200 W external air protection freeze prevention heater, its pond, a flow control valve 5a for high temperature water and a flow control valve 5b for low temperature water, a sequencer, a relay, and the like. The total amount of power required for these devices is 5 to 10 kW, which corresponds to 10% of the generated power of 100 kW. This total electric energy is an electric energy equivalent to 5 to 10% of the electric power lost with auxiliary equipment such as a pump, a control valve and an air blower necessary for the operation of the fuel cell main body.

  On the other hand, attempts have been made to use a fuel cell and natural energy (such as a solar cell) in combination. Patent Document 1 describes an agricultural vinyl house that adjusts a plant cultivation environment for 24 hours by combining a fuel cell and a solar cell. In this agricultural vinyl house, solar cell power is given priority during the daytime. Patent Document 2 describes a power feeding system including a fuel cell and a solar cell. In this power supply system, water is decomposed by surplus power from the solar cell to generate hydrogen, which is supplied to the fuel cell. Patent Document 3 describes a power generation system in which an electrolytic cell of a fuel cell is connected to a solar cell and a wind power generator, and water is electrolyzed to generate hydrogen and supply the fuel cell. As described above, in an attempt to use a conventional fuel cell and a solar cell in combination, electric power from the solar cell is supplied to the fuel cell body, directly used for control of the fuel cell body, or the fuel cell body It was directly used for auxiliary equipment related to the reaction.

JP 2001-258390 A JP 2002-75388 A JP 2001-266923 A

  As described above, when the exhaust heat generated in the fuel cell power generation system 1 is cooled by the air-cooled exhaust heat treatment apparatus 6, the high-temperature water circulation pump 4a and the low temperature are used as the equipment used to operate the air-cooled exhaust heat treatment apparatus 6. The water circulation pump 4b, the cooling fan motor 10, the air cooling type cooling fan 7, the high temperature water flow rate control valve 5a and the low temperature water flow rate control valve 5b, the air cooling type exhaust heat treatment device 6 overall control device, the freeze prevention heater, etc. are required. . Since the total amount of electric power required for these devices used corresponds to 10% of the generated power, another power source corresponding to 10% of the generated electric power is required as energy required for cooling.

  On the other hand, in an attempt to use the above-described conventional fuel cell and solar cell in combination, electric power from the solar cell is supplied to the fuel cell body, directly used for control of the fuel cell body, or the fuel cell body It was directly used for auxiliary equipment related to the reaction. However, since the power generation by solar cells depends on the weather, it is not always possible to maintain a stable power generation amount. For this reason, in an attempt to use a conventional fuel cell power generation system and a solar cell in combination, a stable supply of electric power by the solar cell to the fuel cell main body, direct use for control of the fuel cell main body, or a fuel cell main body There is a problem that it is difficult to directly use it for an auxiliary machine related to the reaction.

  Accordingly, an object of the present invention has been made to solve the above-described problem, and in an attempt to use a fuel cell and a solar cell in combination, a stable supply of electric power by the solar cell to the fuel cell body, a fuel cell Exhaust heat treatment device that treats the exhaust heat generated in the fuel cell power generation system while avoiding difficulties associated with direct use for control of the main body or direct use for auxiliary equipment related to the reaction of the fuel cell main body Another object of the present invention is to provide a waste heat treatment system for a fuel cell capable of supplying a separate power source necessary for the equipment used.

  An exhaust heat treatment system for a fuel cell according to the present invention is an exhaust heat treatment system for a fuel cell in which exhaust heat generated in a fuel cell power generation system is processed by an exhaust heat treatment device, and is generated by a solar cell module as a power source of the exhaust heat treatment device. It is characterized by using the electric power.

  Here, in the exhaust heat treatment system for a fuel cell according to the present invention, the power from the other power device can be used as the power source of the exhaust heat treatment device so that the power generated by the solar cell module can be switched.

  Here, in the exhaust heat treatment system for a fuel cell according to the present invention, the exhaust heat treatment apparatus is air-cooled, and the power source of the exhaust heat treatment apparatus is a circulation pump, a cooling fan, a cooling fan motor, a flow rate of the air-cooled exhaust heat treatment apparatus It can be used for any one or more of a control valve, a control device, and a freeze prevention heater.

  Here, in the exhaust heat treatment system for a fuel cell according to the present invention, when the power generated by the solar cell module generates surplus power more than that used as a power source of the exhaust heat treatment apparatus, the surplus power is used as the fuel cell power generation system. It can be used for charging an auxiliary battery or supplying to an external power system.

  To obtain electrical and thermal energy in a fuel cell power generation system, separate power sources are required for auxiliary equipment such as an air-cooled exhaust heat treatment device that processes exhaust heat generated in the fuel cell power generation system and incidental equipment (use equipment). It becomes. According to the exhaust heat treatment apparatus for a fuel cell of the present invention, in order to save energy that can be said to be a loss, a solar cell power generation apparatus (such as a solar cell module for roof) using sunlight that is natural energy is used. Can do. However, since it is sunlight that depends on the weather, it is related to the supply of power by the solar cell to the fuel cell body, the direct use to control the fuel cell body, or the reaction of the fuel cell body as in the prior art Avoid direct use for auxiliary equipment, etc., and use it exclusively for air-cooled exhaust heat treatment equipment, which is ancillary equipment operating with constant or simple control. As a result, there is an effect that the solar cell power generation system using natural energy that depends on the weather can be effectively used without being interposed in the main body of the fuel cell power generation system 1 that requires a complicated control balance.

  Hereinafter, each embodiment will be described in detail with reference to the drawings.

  Generally, the exhaust heat treatment apparatus for a fuel cell is cooled by using an air-cooling type cooling fan, so that it is usually installed outdoors. Similarly, since a solar cell power generation device uses sunlight, it is usually installed and used outdoors. The exhaust heat treatment system for a fuel cell according to the present invention is a system that uses both of them to use electric power generated by a solar cell power generation device (solar cell module) as a power source of the exhaust heat treatment device for a fuel cell. is there.

  FIG. 1 shows a waste heat treatment apparatus system 30 for a fuel cell according to Embodiment 1 of the present invention. In FIG. 1, the same reference numerals as those in FIG. In FIG. 1, reference numeral 20 denotes sunlight, 21 denotes a building in which the fuel cell power generation system 1 is installed, 22 denotes a solar cell module for roof attached to the roof of the building 21, and 23 denotes a wall attached to the wall of the building 21. The solar cell module 24a is a solar cell module with a device panel attached to the device panel of the air-cooled exhaust heat treatment device 6 installed outside the building 21, and 11 is an outdoor fuel cell main body installed outside the building 21. 24b is a solar cell module with a device panel attached to the device panel of the outdoor fuel cell main body 11, 24c is a solar cell module with a roof attached to the roof of the outdoor fuel cell main body 11, and 25 is outside the building 21. The installed outdoor solar cell module, 32 is a high-temperature water pipe for sending waste heat from the high-temperature water heat exchanger 2, and 33 is a low-temperature hydrothermal exchange A cold water pipe for feeding the waste heat from the vessel 3.

  As shown in FIG. 1, the high-temperature water pipe 32 and the low-temperature water pipe 33 taken out from the high-temperature water heat exchanger 2 and the low-temperature water heat exchanger 3 of the fuel cell power generation system 1 to the air-cooled waste heat treatment apparatus 6 respectively. Then, cooling is performed from 90 ° C. to 40 ° C. on the high-temperature water cooler 8 (see FIG. 1) side, and from 60 ° C. to 40 ° C. on the low-temperature water cooler 9 (see FIG. 1) side.

  As a power source (power source) for this cooling, a solar cell power generator capable of generating power by sunlight 20 only in the daytime (solar cell module 22 for roof, solar cell module 23 for wall, solar cell module with device panel) 24a and 24b, roofed solar cell module 24c, outdoor-installed solar cell module 25, etc.) are installed in the number required for the operation of the air-cooled exhaust heat treatment apparatus 6 and used as a power source. In consideration of the fact that the amount of generated power is not constant due to the weather and cannot be used at night, a fuel cell using a power switching converter that can be used in combination with normal power supply (other power devices) The waste heat treatment apparatus system 30 is provided with a protection function that prevents the system from being stopped.

  When the power generation of the fuel cell power generation system 1 is stopped, the power generated by the solar cell power generation apparatus is charged to the auxiliary battery of the fuel cell power generation system 1 or to the external power system via the power switching converter. It can be used for other equipment by using it to supply to Similarly, when the electric power generated by the solar cell power generation device generates surplus power more than that used as the power source of the air-cooled exhaust heat treatment device 6, the surplus power is similarly used to charge the auxiliary battery of the fuel cell power generation system 1 or to the external power system. It can be used for other equipment by using it to supply to

  Next, specific devices and the like will be described. A solar cell module 22 for roof of about 10 KW is installed for 100 KW PAFC around the air-cooled waste heat treatment apparatus 6 and on the roof, surroundings, or wall of the building 21 where the fuel cell power generation system 1 is installed. Operation control of the air-cooled exhaust heat treatment apparatus 6 is performed through a power switching converter that can be used by switching the power generated by the solar battery power generation apparatus together with normal power supply to the air-cooled exhaust heat treatment apparatus 6.

Next, an outline of the size of each device will be described.
1. The PAFC100KW power generator has a height and width of about 4m x 2m and a height of 2.5m.
2. The air-cooled exhaust heat treatment device 6 for the PAFC power generator has a height and width of about 4.5 m × 1 m and a height of 2 m.
3. The area of the solar cell power generation module 22 for roof equivalent to 10 KW is a flat plate with a vertical and horizontal width of about 8 m × 8 m.

The PAFC main body can be installed outdoors in the same manner as the air-cooled exhaust heat treatment apparatus 6 and the solar cell module 22 for roof. The installation location of the solar cell module 22 for the roof, etc. can be installed in the following places by taking advantage of the flat shape.
1. Since the solar cell module 22 for the roof and the like can be divided and installed in a small size, if there is a building 21 of the PAFC power generation device, the roof solar cell module 22 is divided and installed on the roof or wall of the building 21 to the air-cooled exhaust heat treatment device 6 Supply power.
2. Similarly, when the PAFC main body is installed outdoors, the PAFC main body is dispersedly installed on the panel around the PAFC main body or its roof, in addition to the surrounding buildings installed outdoors. It is also attached to the air-cooled waste heat treatment apparatus 6 itself.
3. When installing only the solar cell module 22 for roofs, etc., it divides | segments and installs in the site | part of the vicinity of a PAFC power generator.

  In order to obtain electric and thermal energy in the fuel cell power generation system 1, separate from auxiliary equipment such as an air-cooled exhaust heat treatment apparatus 6 that processes exhaust heat generated in the fuel cell power generation system 1 and incidental equipment (use equipment). A power supply is required. According to Example 1 of the present invention, in order to save energy for the energy that can be said to be a loss, a solar cell power generation device (such as a solar cell module 22 for roof) that uses sunlight, which is natural energy, can be used. . However, since it is sunlight that depends on the weather, it is related to the supply of power by the solar cell to the fuel cell body, the direct use to control the fuel cell body, or the reaction of the fuel cell body as in the prior art Avoid direct use for auxiliary equipment, etc., and use it exclusively for air-cooled exhaust heat treatment equipment 6 which is ancillary equipment operating with constant or simple control.

  It can be said that the exhaust heat treatment system 30 for a fuel cell according to the present invention is combined with the fuel cell power generation system 1 which is one of the new energies in order to spread the application field of solar cell power generation devices using natural energy. Since the fuel cell power generation system 1 converts gas energy into electric power, there are complicated controls such as gas flow rate supply, cooling water flow rate control, and DC-AC conversion of generated electric power with different reaction speeds. Therefore, in the exhaust heat treatment system 30 for a fuel cell according to the present invention, the solar cell power generator is not used as an auxiliary power source and a control power source for the reaction gas or cooling water of the fuel cell power generation system 1, but exhaust heat generated from the fuel cell. It is used as a dedicated power source for the air-cooled exhaust heat treatment apparatus 6 which is an auxiliary device for cooling. The power source of the air-cooled exhaust heat treatment apparatus 6 includes a circulation pump 4a of the air-cooled exhaust heat treatment apparatus 6, a cooling fan 7, a cooling fan motor 10, a flow control valve 5a, etc., a control device (not shown), and an anti-freezing heater (not used). 1) or more. As a result, it is possible to effectively use the solar cell power generation system using natural energy that depends on the weather without being interposed in the main body of the fuel cell power generation system 1 that requires a complicated control balance.

  As mentioned above, according to Example 1 of this invention, in the trial which uses a fuel cell and a solar cell together, the stable supply to the fuel cell main body of the electric power by a solar cell, and direct control to the control of a fuel cell main body Use of the air-cooled exhaust heat treatment apparatus 6 for treating exhaust heat generated in the fuel cell power generation system 1 while avoiding difficulties associated with use or direct use of auxiliary equipment related to the reaction of the fuel cell body It is possible to provide the exhaust heat treatment system 30 for a fuel cell that can supply a necessary separate power source.

  As an application example of the present invention, a fuel cell capable of effectively utilizing a solar cell power generation system using natural energy that depends on the weather without interposing it in a fuel cell power generation system body that requires a complicated control balance Application to power generation systems. As the fuel cell, a phosphoric acid fuel cell (PAFC) can be applied.

It is a figure which shows the exhaust-heat-treatment apparatus system 30 for fuel cells in Example 1 of this invention. It is a figure which shows the air-cooling type waste heat processing apparatus 6 in the conventional fuel cell power generation system 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel cell power generation system, 2 High temperature water heat exchanger, 3 Low temperature water heat exchanger, 4a High temperature water circulation pump, 4b Low temperature water circulation pump, 5a Flow control valve for high temperature water, 5b Flow control valve for low temperature water, 6 Air-cooled exhaust Heat treatment device, 7 Air-cooled cooling fan, 8 High-temperature water cooler, 9 Low-temperature water cooler, 10 Cooling fan motor, 11 Outdoor fuel cell body, 20 Sunlight, 21 Building, 22 Solar cell module for roof, 23 Solar cell module for walls, 24a, 24b Solar cell module with device panel, 24c Solar cell module with roof, 25 Outdoor solar cell module, 30 Fuel cell waste heat treatment system, 32 High temperature water piping, 33 Low temperature water piping.

Claims (4)

  An exhaust heat treatment system for a fuel cell that processes exhaust heat generated in a fuel cell power generation system using an exhaust heat treatment device, wherein the power generated by the solar cell module is used as a power source of the exhaust heat treatment device. Waste heat treatment system.   2. The fuel cell exhaust heat treatment system according to claim 1, wherein the power source of the exhaust heat treatment apparatus uses electric power generated by the solar cell module so as to be switchable from another electric power apparatus. Waste heat treatment system.   3. The exhaust heat treatment system for a fuel cell according to claim 1, wherein the exhaust heat treatment apparatus is air-cooled, and the power source of the exhaust heat treatment apparatus is a circulation pump, a cooling fan, a cooling fan motor of the air-cooling exhaust heat treatment apparatus, A waste heat treatment system for a fuel cell, which is used for any one or more of a flow control valve, a control device, and a freeze prevention heater. 4. The fuel cell exhaust heat treatment system according to claim 1, wherein when the electric power generated by the solar cell module generates surplus power more than that used as a power source of the exhaust heat treatment apparatus, the surplus power is An exhaust heat treatment system for a fuel cell, which is used for charging an auxiliary battery of the fuel cell power generation system or supplying the auxiliary battery to an external power system.

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