JP2001351663A - Fuel cell device and electric generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a power generation output efficiencies of a fuel cell device and an electric generator by disusing separate cooling air but cooling the fuel cell device only by compressed air necessary for operation. SOLUTION: A power generation part 20 is cooled at a reaction gas heat exchanger 24 by the fuel and air introduced for the operation of the power generation part 20. Introduction of separate cooling air is disused and only compressed air necessary for the operation is introduced, consequently, power generation ratio against the volume of air is heightened by reducing a motive force of a compressed air blower for the fuel cell device, and power output/ power efficiency of the fuel cell device, and output/efficiency of the electric generator the improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell device and a power generation facility using the fuel cell device.

[0002]

2. Description of the Related Art A fuel cell generates electric energy with high power generation efficiency and also generates heat energy through a cell body and exhaust gas. Therefore, the exhaust heat is transferred to the gas turbine (GT) topping cycle and the steam turbine (S
If collected by a bottoming cycle such as T) and used for power generation, higher power generation efficiency can be obtained. For this reason,
A combined cycle power plant combining a fuel cell and a gas turbine is expected to have a high energy saving effect.

[0003] In a fuel cell, the oxygen required for the reaction of the air electrode is supplied by taking in air, so that it is necessary to increase the oxygen partial pressure. Generally, air taken in from the atmosphere is pressurized by a compressor. Pressurized supply to the air electrode of the fuel cell. As a driving power source for the compressor, a gas turbine is used as a working fluid by burning exhaust gas from the fuel cell, and a compressor is coaxially connected to the gas turbine to drive the gas turbine. There is known a method in which a generator is driven to generate electric power, and a compressor is driven by an electric motor.

[0004]

By the way, the fuel cell device generates electric energy with high power generation efficiency. However, the fuel cell power generation unit has a high temperature due to the effect of the reaction heat at which the fuel and air (oxygen) react at an equivalent ratio. Problem. For this reason, conventionally, the operation air supplied to the air electrode has been taken in a larger amount than required for combustion, thereby suppressing the temperature rise of the fuel cell power generation unit. However, when a large amount of air is taken in, the gas turbine is operated while the residual oxygen in the exhaust gas is large. When the gas turbine is used with the gas turbine inlet temperature set higher than the fuel cell exhaust gas, the remaining oxygen is consumed by the introduction of fuel, but the gas is exhausted from the gas turbine at a considerable concentration. The residual oxygen (that is, the amount of air) that does not contribute to power generation is excessively pressurized. For this reason, a large power is required for the compressor, the blower, and the like, which is a major factor that lowers the power generation efficiency of the entire plant.

The present invention has been made in view of the above circumstances, and does not supply an excessive fluid (air) for cooling to a fuel cell and uses a special cooling device separate from a combustion fluid. It is an object of the present invention to provide a fuel cell device capable of suppressing the temperature of the fuel cell power generation unit from becoming high and a power generation facility using the fuel cell device.

[0006]

According to a first aspect of the present invention, there is provided a fuel cell device comprising: a fuel cell power generation unit for generating power by reacting air and fuel through an electrolyte membrane; A combustion unit that burns an air electrode exhaust gas and a fuel electrode exhaust gas discharged from the fuel cell to generate combustion gas, and at least one of air and fuel for operating the fuel cell power generation unit is introduced to introduce the fuel cell power generation unit And cooling means for cooling the cooling device.

According to another aspect of the present invention, there is provided a fuel cell device for generating power by reacting air and fuel through an electrolyte membrane, and discharging the fuel cell from the fuel cell power generation unit. A combustion unit for burning the cathode exhaust gas and the fuel electrode exhaust gas to generate combustion gas, a heating unit for heating air and fuel for operating the fuel cell power generation unit with exhaust gas from the fuel cell power generation unit, And a cooling means for cooling the fuel cell power generation unit by charging at least one of air and fuel for operating the unit.

[0008] The air and the fuel introduced into the cooling means are the air and the fuel heated by the heating unit. Further, the air and the fuel introduced into the heating unit are air and fuel after the cooling unit cools the fuel cell power generation unit.

[0009] In the power generation equipment for achieving the above object, a fuel pump system may be freely configured, but the fuel is pumped by a pump of equipment of another system. Further, the air is pressure-fed by air supply means of equipment of another system. Further, the air supply means is a compressor. Further, the air supply means is a blower. Further, the combustion gas generated in the combustion section is supplied to a power generation facility of another system.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a fuel cell system according to the present invention. 1 shows a schematic configuration of a power generation facility according to an embodiment of the present invention, FIG. 2 shows a schematic configuration of a fuel cell device according to an embodiment of the present invention, and FIG. 3 shows a circulation system of a cooling fluid. It is.

As shown in FIG. 1, a power generation facility 1A according to this embodiment includes a fuel cell device 2 and a gas turbine power generation unit 30.
And an exhaust heat recovery unit 40 that recovers the exhaust heat of the gas turbine power generation unit 30. The fuel cell device 2 includes a fuel cell power generation unit (power generation unit) 20, a combustion unit 22, and a reaction fluid heater 10. The power generation unit 20 generates power by reacting, for example, natural gas as a fuel with air as an oxidant through a solid oxide electrolyte membrane, and has an internal reforming (steam reforming reaction) function. Combustion unit 22, the unburned in the exhaust gas G ₂₀ of the power generation unit 20 is burned to produce hot combustion gases G _22. The reaction gas heater 10 is composed of a fuel gas heater 11 and an air heater 12. The fuel gas heater 11 and the air heater 12 provide heat between the high-temperature combustion gas G ₂₂ from the combustion unit 22. Heated by replacement. A reaction gas heat exchange unit 24 as a cooling unit is provided for the power generation unit 20 and the combustion unit 22.

The reaction gas heat exchanging section 24 comprises a fuel gas heat exchanging section 24a and an air heat exchanging section 24b.
Fuel gas heat exchange portion 24a in its interior, the desired operating temperature the power generation portion 20 by the natural gas F ₂₄ to be supplied to the fuel electrode by recovering heat generated power generation portion 20 is heated to the desired temperature The air heat exchanging unit 24b collects the heat generated by the power generation unit 20 and raises the temperature of the air A ₂₄ supplied to the air electrode to a desired temperature. This is for cooling and maintaining the power generation unit 20 at a desired operating temperature.

On the other hand, the GT power generation section 30 includes a gas turbine (GT) 32, an air compressor 34, a power generator 36, and a heat exchanger 38. The gas turbine 32
The combustion gas G ₂₂ discharged from the combustion unit 22 recovers power as the working fluid. The air compressor 34 is a gas turbine 3
2 and is coaxially connected thereto, and is operated by the power of the gas turbine 32 to suck and compress the air A ₉₀ from an air supply unit 90 (for example, the air is sucked through an air suction chamber). The generator 36 is connected to the gas turbine 32 via the air compressor 34.
And is operated coaxially with the gas turbine 32 to generate electric power. The heat exchanger 60 heats the compressed air A _34a from natural gas F ₈₀ and air compressor 34 from the fuel gas supply unit 80.

The GT exhaust heat recovery system 40 includes a steam generator (HRSG) 41, a steam turbine (ST) 42, a generator 43, a condenser 44, and a chimney 46. Steam generator 41 is, after the exhaust gas G ₃₂ discharged from the gas turbine 32 of the GT power generation portion 30 becomes the exhaust gas G ₆₀ through the heat exchanger 60, to generate steam by utilizing the heat, steam some S _41a is an internal reforming steam to be mixed to the natural gas, most of the steam S _41b to supply to the outside of the steam turbine 42.

The steam turbine 42 recovers power using the steam S _{41 b} supplied from the steam generator 41 as a working fluid. The generator 43 is coaxially connected to the steam turbine 42 and operates by the power of the steam turbine 42 to generate electric power. The condenser 44 condenses the steam S ₄₂ discharged from the steam turbine 42 and sends the condensed water W _{42 a} to the steam generator 41. The compressed air A ₃₄ may be used as (1) the compressor discharge as it is, (2) may be used after being heated by the heat exchanger 64, or may be used at a predetermined temperature by using (1) and (2) together. May be used. The exhaust gas G41 that has passed through the steam generator ₄₁ is released from the chimney 46 into the atmosphere.

The natural gas F ₈₀ (about 15 ° C.) supplied from the fuel gas supply unit 80 is supplied to the heat exchanger 6 in the GT power generation unit 30.
2 and preheated. The natural gas F62 that has passed through the heat exchanger ₆₂ is mixed with the internal reforming steam _S41a supplied from the steam generator 41. Alternatively, it may be sprayed mixed natural gas F ₆₂ directly with water without using an internal reforming steam S _41a. Heater 1 mixed with internal reforming steam S _41a
Natural gas F ₅₂ which was heated at 1 is introduced into the fuel gas heat exchange portion 24a of the reaction gas heat exchange section 24. The natural gas F ₂₄ introduced into the fuel gas heat exchange unit 24a is heated to an optimum operating temperature (fuel reforming temperature) by recovering the heat generated by the power generation unit 20, and the heat exchange is performed. The power generation unit 20 is also cooled and maintained at a desired operating temperature.
Then, natural gas F ₂₄ heated to the optimum operating temperature,
It is introduced to the fuel electrode of the power generation unit 20.

On the other hand, from the air supply unit 90 to the GT power generation unit 30
Air A taken in₉₀(Eg, 15 ° C) is empty
The temperature is raised by being compressed by the gas compressor 34. Pressure
Compressed air A₃₄Is supplied to the heat exchanger 64. Heat exchanger 6
4 compressed air A₆₄Was heated in the heat exchanger 12.
After that, it is introduced into the air heat exchange part 24b of the reaction gas heat exchange part 24.
Is done. Compressed air A introduced into the air heat exchange section 24b
_{twenty four}Recovers heat from the heat generated by the FC power generation unit 20 and performs fuel reforming.
The temperature is raised directly to the temperature, and the FC power generation unit 20
Each time it is kept cool. Then raise the temperature to the optimal operating temperature.
Compressed air A _{twenty four}Is introduced into the air electrode of the power generation unit 20
You.

In the power generation unit 20, the fuel is introduced into the fuel electrode.
Mixed gas F of natural gas and steam _{twenty four}Is the fuel electrode
Medium) to produce hydrogen. This internal reforming reaction
Is an endothermic reaction (steam reforming of methane).
The heat generated by the FC power generation unit 20 is absorbed by the reaction. Ma
Compressed air A at the cathode_{twenty four}The oxygen inside is O^2-Ion
Move through the solid electrolyte membrane,
Causes combustion reaction with carbon monoxide. Here, the heat of reaction
Of which, the remaining converted to electrical energy (DC power)
Minutes are generated as heat. The production of water or carbon dioxide
Although it is a thermal reaction, the reaction gas provided in the FC power generation unit 20
FC power generation because it is appropriately absorbed and cooled by the heat exchange unit 24
The temperature of the section 20 is maintained at a predetermined operating temperature.

The anode exhaust and cathode exhaust gas passing through the power generating unit 20 is introduced into the combustion section 22 as an exhaust gas G _20. In this combustion section 22, and the natural gas components and unreacted oxygen remaining in the exhaust gas G _20, readily undergo combustion reaction under elevated temperatures, the combustion gas G _22.

In the combined power plant 1A, the power generation unit 2
The air is exchanged by the air heat exchanger 24b attached to the
The temperature is directly raised by the heat generated by the power generation unit 20, and the cooling thereof keeps the FC power generation unit 20 at a predetermined operating temperature. Therefore, conventionally, the temperature rise is at most 100 ° C., but in the present technology, the air temperature rise width is several 100 ° C.,
Air flow rate can be reduced. That is, the utilization rate of air in cooling is improved. In other words, F
The C output increases. The fuel gas heat exchanging unit 24a is installed in combination with the air heat exchanging unit 24b. In addition to the air, the fuel gas is also directly heated by collecting the heat generated by the FC power generation unit 20. That is, the FC power generation unit 20 uses two fluids, air and fuel.
Is cooled and maintained at a predetermined operating temperature range.

Furthermore, high temperature exhaust gas G ₂₂ discharged from the combustion unit 22 is supplied to the GT power generation portion 30 then was allowed reduced by heat recovery in the reaction gas heater 10. Greatly improved since obtain a predetermined turbine inlet temperature by the combustor 31 already exhaust gas G ₅₀ is less fuel input in the combustor 31 as is the high temperature, than a conventional combined cycle power plant described a plant efficiency previously Can be done.

On the other hand, the exhaust gas G ₂₂ is a high temperature discharged from the combustion section 22, is introduced into the gas turbine 32 of the GT power generation portion 30, to drive the gas turbine 32. As a result, the gas turbine 32 serves as a driving power source, and the air compressor 34 and the generator 36 connected coaxially with the gas turbine 32 operate. Exhaust gas G ₃₂ discharged from the gas turbine 32 is introduced after the steam generator 41 via the heat exchanger 60,
Part of the steam generated by the steam generator 41 is used as the internal reforming steam S _{41 a} as described above, and most of the remaining steam S _{41 b} is supplied to the steam turbine 42.

The steam S _41b is _supplied to the steam turbine 42
Is a driving power source, and a generator 4 coaxially connected to the driving power source.
3 operates to generate electric power. The steam S _{41 b} is recovered in energy by the steam turbine 42 and discharges the discharged steam S ₄₂ ,
It is introduced into the condenser 44. From condenser 44, condensate W _42a
To the steam generator 41. On the other hand, the exhaust gas G ₄₁ discharged from the steam generator 41 is released from the chimney 46 into the atmosphere.

The schematic configuration of the fuel cell device 2 of the power generation facility 1A shown in FIG. 1 and the circulation of fuel and air as a cooling fluid will be described with reference to FIGS.

As shown in the figure, the natural gas F ₆₂ and the compressed air A ₆₄ are supplied to the fuel gas heater 11 in the combustion section 22.
And the air is heated to a predetermined temperature at which the power generation unit 20 is cooled. Then, the natural gas F ₂₄ and the compressed air A ₂₄ for FC operation are injected into the power generation unit 20 while cooling the FC. . The exhaust gas G ₂₀ of the power generation unit 20 is the heating medium in the fuel gas heater 11 and air heater 12 while being burned in the combustion section 22 as the combustion gas G _22.

As described above, since the power generation unit 20 is cooled by the natural gas F ₆₂ and the compressed air A ₆₄ introduced for the operation of the power generation unit 20, it is not necessary to separately introduce air for cooling. For this reason, only the compressed air necessary for the operation needs to be introduced from the compressor 34, and the power of the compressor 34 for the fuel cell device 2 is reduced. Can be reduced.

Another embodiment of the fuel cell device will be described with reference to FIGS. 4 and 5 show a circulation system of a cooling fluid of a fuel cell device according to another embodiment of the present invention.

As shown in FIG. 4, the natural gas F ₆₂ and the compressed air A ₆₄ are provided in the combustion section 22 by the fuel gas heater 1.
1 and the air heater 12. Fuel gas heater 11
The natural gas heated to the middle temperature in the fuel gas heater 1
4 (the fuel gas heater 11 and the fuel gas heater 14 in FIG. 4 correspond to the fuel gas heater 11 in FIG. 1), and are then supplied to the power generation unit 20 as natural gas for operation. The compressed air heat-exchanged by the air heater 12 is supplied to the air heat exchange section 24b.
After cooling the power generation unit 20 (see the air heater 12 in FIG. 1).
), And at the same time, it is supplied to the power generation unit 20 as compressed air for operation, and at the same time, part of the heat is exchanged by the fuel heater 14 to reduce the temperature and join the upstream side of the air heat exchange unit 24b. The compressed air whose temperature has been reduced by heat exchange in the fuel heater 14 is blower 1
5 to the upstream side of the air heat exchange section 24b.

The fuel cell device shown in FIG.
Compressed air A for operation in section 24b₆₄Departs only by
The cooling of the electric unit 20 is performed. Natural gas F₆₂Heating
A part of the compressed air heated by the electric
The compressed air whose temperature has been reduced due to heat is recirculated to the air heat exchange section.
Reheated at 24b. For this reason, the compressed air for operation A ₆₄
Only the cooling of the entire power generation unit 20 is performed,
Natural gas F₆₂The amount of heating for
You.

As shown in FIG. 5, the fuel gas heater 1 in which the natural gas F ₆₂ and the compressed air A ₆₄ are formed in the combustion section 22.
1 and the air heater 12. The power generation unit 20 includes a cooling unit (the fuel gas heat exchange unit 24a, the air heat exchange unit 24 in FIG. 1).
A cooling gas (steam or air) circulating through the heat exchanger 19 is introduced into the cooling unit 17 by the blower 18. Fuel gas heater 11
And natural gas F ₆₂ and compressed air A ₆₄ which has been heated in the middle of the temperature in the air heater 12 is introduced to the power generation unit 20 as the natural gas and compressed air for operating is heat exchanged in heat exchanger 19. That is, the cooling of the power generation unit 20 is performed by the circulating fluid in which heat is exchanged with the working natural gas and the compressed air, and the working natural gas and the compressed air indirectly contribute to the cooling.

In the combined cycle power plant 1A shown in FIG. 1, the combustion section 22 is provided outside the reaction gas heat exchange section 24.
Thus, the reaction gas heater by the heat of the combustion gas G ₂₂ 1
At 0, the fuel gas and air can be heated to a high temperature. The GT power generation unit 30 includes a gas turbine 3
A combustor 31 is provided on the gas line on the upstream side of 2. Combustor 31, the exhaust gas G ₅₀ discharged from the reaction gas heater 10 provided for the hot gas of a predetermined temperature prior to introduction into the gas turbine 32, by heat exchange of the reaction gas heater 10, the reduction was raised was discharged gas G ₅₀ increase the temperature again.

Power generation equipment 1 according to another embodiment of the present invention
B will be described. FIG. 6 is a schematic configuration of a power generation facility according to another embodiment of the present invention, FIG. 7 is a schematic configuration of a fuel cell device according to another embodiment of the present invention, and FIG. Is shown. Note that the same components as those of the power generation facility 1A shown in FIGS. 1 to 5 are denoted by the same reference numerals, and redundant description is omitted.

The natural gas F ₈₀ (for example, 15 ° C.) supplied from the fuel gas supply section 80 is introduced into the fuel gas heat exchange section 24 a of the reaction gas heat exchange section 24. The natural gas F ₈₀ introduced into the fuel gas heat exchange unit 24 a is directly heated by the heat generated by the power generation unit 20. Fuel gas heat exchange section 2
Natural gas F _24a discharged from 4a is introduced into the fuel gas heater 11 of the reaction gas heater 10, further raising the temperature by the heat exchanger combustion gases G _22. Fuel gas heater 1
1 natural gas F ₅₂ that has passed through the is mixed with internal reforming steam S _41a supplied from the steam generator 41. Natural gas F ₅₂ intermingled with internal reforming steam S _41a is introduced to the fuel electrode of the power generation unit 20. Depending on the steam temperature conditions, the natural gas mixed with the steam may be natural gas F ₈₀ or natural gas F
_24a .

[0034] Thus, by utilizing a fuel gas heat exchanger section 24a and the fuel gas heater 11, it can be heated to the optimum operating temperature of the natural gas F ₉₀ introduced at low temperatures, F
When the C power generation unit 20 is maintained at a predetermined operating temperature, the power generation unit 20 can be cooled more efficiently with lower-temperature fuel than the power generation equipment 1A.

On the other hand, from the air supply unit 90 to the GT power generation unit 30
Compressed air A ₃₄ supplied via the air compressor ₃₄
Even in the same manner as the above natural gas is introduced into the air heat exchanger section 24b, it is introduced to the air electrode of the power generation unit 20 through the air heater 12 as the compressed air A _54.

When the plant is started, the power generation unit 20
Can be instantaneously heated to a predetermined operating temperature by effectively utilizing its own exhaust heat, that is, the heat of the reaction gas heat exchange unit 24. This makes it easier to control the stabilization of the FC at the time of starting the plant, and shortens the time required to reach a steady operation state. When the plant is in a steady operation state, a large amount of heat is generated from the power generation unit 20 by the air heat exchange unit 24b.
And the fuel gas heat exchange section 24a, the amount of heat to be given to the air and the fuel gas from the air heater 12 and the fuel gas heater 11 is a minimum required.

Thus, for example, when the plant enters a steady state, the heat exchange rate of the reaction gas heater 10 can be changed, and the gas line can be switched between fuel gas and air paths. Or burning part 2
By adopting a possible configuration and the like switching the path 2 of the combustion gas G _22, can be supplied to the GT power generation portion 30 while maintaining as much as possible to the hot combustion gases in the combustion section 22.
In this case, the combustor 31 of the GT power generation unit 30 may not be necessary, and these effects can further improve the plant efficiency.

The schematic configuration of the fuel cell device 2 of the power generation facility 1B shown in FIG. 6 and the circulation of fuel and air as a cooling fluid will be described with reference to FIGS.

As shown in the figure, the natural gas F ₈₀ and the compressed air A ₃₄ are introduced into the fuel gas heat exchange section 24a and the air heat exchange section 24b of the power generation section 20 to cool the power generation section 20.
The natural gas F _24a and the compressed air A _24b that have cooled the power generation unit 20 are provided in the combustion unit 22 by the fuel gas heater 11
And is introduced into air heater 12, is introduced into the power generation unit 20 as the natural gas F ₅₂ and compressed air A ₅₄ for working. The exhaust gas G ₂₀ of the power generation unit 20 is burned in the combustion portion 22 the combustion gas G
₂₂ becomes a heating medium for the fuel gas heater 11 and the air heater 12.

[0040] In this manner, cooling of the power generation section 20 by cold natural gas F ₆₂ and compressed air A ₆₄ to be introduced for operation of the power generation unit 20, the natural gas F ₆₂ and compressed air after the cooling since the a ₆₄ is heated to a predetermined temperature for operating at a fuel gas heater 11 and air heater 12, it is not necessary to separately introducing air for cooling. Therefore, only the air necessary for the combustion operation needs to be introduced from the compressor 34, and the power of the compressor 34 for the fuel cell device 2 is reduced. Since the temperature difference between the power generation unit 20 and the cooling fluid (the natural gas _F62 and the compressed air _A64 ) can be increased, the cooling of the power generation unit 20 is facilitated. Further, the control for raising the temperature to the predetermined temperature for operation becomes easy.

Another embodiment of the fuel cell device will be described with reference to FIGS. 9 and 10 show a circulation system of a cooling fluid of a fuel cell device according to another embodiment of the present invention.

As shown in FIG. 9, natural gas F₈₀Is a fuel gas
Natural gas F _24aBecome fuel gas
To the heater 11. Heated by fuel gas heater 11
Natural gas for operation is natural gas F_{twenty four}Power generation unit 20
It is thrown into. Also, compressed air A₃₄Is the air heat exchange unit 24
After cooling the power generation unit 20 in b, the fuel gas heater 8
The heat is exchanged and the pressure is increased by the blower 9 to the air heater 12.
Sent. Compressed air A heated by air heater 12₅₄Is
The power is supplied to the power generation unit 20 for operation.

In the fuel cell device shown in FIG. 9, the power generation unit 20 is cooled only by the operating air A ₃₄ in the air heat exchange unit 24b. Compressed air heated at the power generation unit 20 is used for heating the natural gas F ₈₀ , and the compressed air whose temperature has been reduced as a result of fuel heating is recirculated and reheated by the air heater 12, and the compressed air A ₅₄ for operation is used. Becomes Therefore, only the cooling of the power generation section 20 in the compressed air A ₃₄ for working is performed. The power generation unit 20
Is cooled by low-temperature compressed air, so that the temperature of the compressed air passing through the fuel gas heater 8 can also be reduced, and the temperature of the compressed air pressurized by the blower 9 can be reduced. Therefore, the power of the blower 9 can be reduced, and the power of the auxiliary machine can be minimized.

As shown in FIG. 10, the power generation unit 20 includes a cooling unit (the fuel gas heat exchange unit 24a and the air heat exchange unit 24 shown in FIG. 6).
b), and a fluid (for example, steam or air) circulated through the heat exchanger 5 by the blower 6 in the cooling unit 7
Is introduced. The natural gas F ₈₀ and the compressed air A _{34 undergo} heat exchange in the heat exchanger 5 and are introduced into the fuel gas heater 11 and the air heater 12 configured in the combustion section 22. Natural gas and compressed air in the fuel gas heater 11 and the air heater 12 is heated to a predetermined temperature, it is charged to the power generation unit 20 as the compressed air A ₅₄ natural gas F ₂₄ and for operating for operating.

That is, the cooling of the power generation unit 20 is performed by the circulating fluid in which heat is exchanged with the working natural gas and the compressed air, and the working natural gas and the compressed air indirectly contribute to the cooling. Then, the heat exchanger 5, because the low-temperature natural gas F ₈₀ and compressed air A ₃₄ and the circulating fluid to the heat exchanger, can suppress the temperature of the circulating fluid itself cool.
As a result, the power of the blower 6 can be reduced, and the power of the auxiliary machine can be minimized.

In the embodiment described above, the GT power generation unit 30
Although the example in which the fuel cell device 2 is applied to the combined power generation facility in which the fuel cell system 2 is combined with the GT exhaust heat recovery system 40 has been described, the invention can be applied to other power generation facilities. In this case, the fuel is pumped by a pump of another facility, and the compressed air is introduced by a compressor (for a pressurized facility) or a blower (for a normal pressure facility) of the other facility. Further, the combustion gas generated by the fuel cell device 2 is collected by another facility.

[0047]

As described above, the fuel cell device of the present invention and the power generation equipment to which the fuel cell device is applied include a fuel cell power generation unit for generating power by reacting air and fuel via an electrolyte membrane, and a discharge unit from the fuel cell power generation unit. The combustion unit that generates the combustion gas by burning the air electrode exhaust gas and the fuel electrode exhaust gas, and the air or both air and fuel for operating the fuel cell power generation unit are introduced by introducing the fuel cell power generation unit. There is no need to separately introduce extra cooling air as compared with combustion air. As a result, only the compressed air necessary for the operation needs to be introduced, the power of the pneumatic pressure source for the fuel cell device becomes relatively small, and the ratio of the power generation output to the air amount can be increased. And the output / efficiency of the entire power generation facility is improved.

Further, the fuel cell device of the present invention and the power generation equipment to which the fuel cell device is applied include a fuel cell power generation unit for generating power by reacting air and fuel through an electrolyte membrane, A combustion unit that burns the air electrode exhaust gas and the fuel electrode exhaust gas to generate combustion gas, and a heating unit that heats the operating air or both air and fuel of the fuel cell power generation unit with the exhaust gas of the fuel cell power generation unit. And a cooling means for cooling the fuel cell power generation section by at least one of the air and fuel for operating the fuel cell power generation section being supplied, wherein the air for cooling is additionally provided in excess of the air for combustion. No need to introduce. As a result, only the compressed air necessary for the operation needs to be introduced, the power of the pneumatic pressure source for the fuel cell device becomes relatively small, and the ratio of the power generation output to the air amount can be increased. And the output / efficiency of the entire power generation facility is improved. The fuel and air supplied from the gas turbine are supplied to the fuel cell at a low temperature without any heating. At this time, since the temperature rise of the air (air and fuel) as the cooling medium is widened, the cooling operation of the fuel cell becomes very easy,
Further, the heat transfer area of the heat exchange portion can be reduced (that is, the heat exchange area can be made compact).

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a power generation facility according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a fuel cell device according to an embodiment of the present invention.

FIG. 3 is a diagram of a circulation system of a cooling fluid.

FIG. 4 is a circulation system diagram of a cooling fluid of a fuel cell device according to another embodiment of the present invention.

FIG. 5 is a circulating system diagram of a cooling fluid of a fuel cell device according to another embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of a power generation facility according to another embodiment of the present invention.

FIG. 7 is a schematic configuration diagram of a fuel cell device according to another embodiment of the present invention.

FIG. 8 is a circulation system diagram of a cooling fluid.

FIG. 9 is a circulating system diagram of a cooling fluid of a fuel cell device according to another embodiment of the present invention.

FIG. 10 is a circulating system diagram of a cooling fluid of a fuel cell device according to another embodiment of the present invention.

[Description of Signs] 1A, 1B Power generation equipment 2 Fuel cell device 5,19 Heat exchanger 6,9,15,18 Blower 7,17 Cooling unit 8 Fuel gas heater 10 Reaction gas heater 11 Fuel gas heater 12 Air Heater 14 Fuel gas heater 20 Fuel cell power generation unit (power generation unit) 22 Combustion unit 24 Reaction gas heat exchanger 30 GT power generation unit 32 Gas turbine 34 Air compressor 36 Generator 38 Heat exchanger 40 GT exhaust heat recovery system

Claims (9)

[Claims] 1. A fuel cell power generation unit for generating power by reacting air and fuel through an electrolyte membrane, and burning an air electrode exhaust gas and a fuel electrode exhaust gas discharged from the fuel cell power generation unit to generate a combustion gas. A fuel cell device, comprising: a combustion section that performs cooling; and cooling means that cools the fuel cell power generation section by introducing at least one of air and fuel for operating the fuel cell power generation section. 2. A fuel cell power generation unit for generating power by reacting air and fuel through an electrolyte membrane, and burning an air electrode exhaust gas and a fuel electrode exhaust gas discharged from the fuel cell power generation unit to generate a combustion gas. And a heating unit for heating the operating air and fuel of the fuel cell power generation unit with the exhaust gas of the fuel cell power generation unit, and at least one of the operating air and fuel for operating the fuel cell power generation unit. And a cooling means for cooling the fuel cell power generation section. 3. The fuel cell device according to claim 2, wherein the air and fuel introduced into the cooling means are air and fuel heated by a heating unit. 4. The fuel cell device according to claim 2, wherein the air and the fuel introduced into the heating unit are the air and the fuel after the cooling unit cools the fuel cell power generation unit. 5. A power generation facility to which the fuel cell device according to any one of claims 1 to 4 is applied, wherein the fuel is pumped by a pump of a facility of another system. 6. The power generation equipment according to claim 1, wherein the air is pressure-fed by air supply means of equipment of another system. 7. The power generation facility according to claim 6, wherein said air supply means is a compressor. 8. The power generation facility according to claim 6, wherein said air supply means is a blower. 9. The power generation equipment according to claim 1, wherein the combustion gas generated in the combustion part is supplied to a power generation equipment of another system.