Power generation system and fuel supply system

Abstract

To provide a power generation system and a fuel supply system that can sufficiently reduce power generation cost.SOLUTION: A power generation system comprises: pipelines 5a-5c that supply second gas exhausted from a hydrogen tank 20 to a separator 12; a gas-liquid separation tub 6 that separates water content included in the second gas caused to pass through the separator 12; an ejector 8 that is disposed between the pipelines 5a and 5c, and can suck in gas from an introduction port 8d through the passage of the second gas exhausted from the hydrogen tank 20 and join it to the second gas exhausted from the hydrogen tank 20; and a pipeline 7 that guides the second gas from which the water content is separated in the gas-liquid separation tub 6 to the introduction port 8d of the ejector.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a power generation system configured to generate power by reacting a first gas containing an oxidant with a second gas containing hydrogen, and a fuel supply system configured to supply the second gas to a power generation cell of the power generation system. [Background technology]

[0002] For example, the following patent document discloses a fuel cell system including a fuel cell stack and a fuel supply system that supplies hydrogen gas to the fuel cell stack as fuel. In this case, the fuel supply system (hydrogen tank) is connected to an inlet on the anode side of the fuel cell stack by a hydrogen supply pipe. The hydrogen supply pipe is also provided with a main valve that switches between supplying and stopping hydrogen gas from the hydrogen tank, a pressure reducing valve (regulator) that adjusts the hydrogen pressure, an injector that adjusts the amount of hydrogen gas supplied, and a pressure sensor that measures the pressure of the hydrogen gas injected from the injector.

[0003] A gas-liquid separator that separates exhaust gas (a mixture of unreacted hydrogen gas and water) into hydrogen gas and water is connected to the anode-side exhaust port of the fuel cell stack. An exhaust drain pipe is connected to this gas-liquid separator via an exhaust drain valve, and a configuration is adopted in which the water stored in the gas-liquid separator (water separated from the exhaust gas) is discharged into the exhaust drain pipe together with gas containing impurities by controlling the exhaust drain valve to an open state. A circulation flow path is connected to the gas-liquid separator to return the separated hydrogen gas to the hydrogen supply pipe (to be merged with the hydrogen gas supplied from the hydrogen tank to the fuel cell stack), and a hydrogen pump is disposed in the circulation flow path to pump hydrogen gas from the gas-liquid separator to the hydrogen supply pipe.

[0004] In this fuel cell system, the supply of hydrogen gas from the hydrogen tank is started by controlling the main valve to an open state, and the hydrogen gas is injected from the injector and supplied to the anode side of the fuel cell stack after the pressure is adjusted by the pressure reducing valve. At this time, the control unit controls the injector according to the measurement results by the pressure sensor to adjust the amount of hydrogen gas supplied to the fuel cell stack (anode side).

[0005] Furthermore, the exhaust gas discharged from the fuel cell stack (anode side) is separated into hydrogen gas and water in a gas-liquid separator. Here, the separated water is stored in the gas-liquid separator and is discharged into the exhaust drain pipe together with gas containing impurities when the exhaust drain valve is controlled to be in an open state. Furthermore, the separated hydrogen gas is pumped by a hydrogen pump through a circulation flow path to a hydrogen supply pipe. As a result, the hydrogen gas separated in the gas-liquid separator is merged with the hydrogen gas being supplied from the hydrogen tank to the fuel cell stack, and the unreacted hydrogen gas that did not contribute to power generation is reused as part of the fuel, thereby reducing the amount of hydrogen gas consumed. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2023-038620 A (Pages 4-11, Figures 1-7) Summary of the Invention [Problem to be solved by the invention]

[0007] However, the fuel cell system disclosed in the above-mentioned patent document has the following problems to be solved. Specifically, the above-mentioned fuel cell system generates electricity by supplying hydrogen gas from a fuel supply system (hydrogen tank) to a fuel cell stack (anode side) via a hydrogen supply pipe, and also separates exhaust gas (a mixture of unreacted hydrogen gas and water) from the fuel cell stack into hydrogen gas and water in a gas-liquid separator, and the separated hydrogen gas is merged with the hydrogen gas in the hydrogen supply pipe via a circulation flow path and reused.

[0008] In this case, the fuel cell system employs a configuration in which hydrogen gas separated in the gas-liquid separator is pumped to a hydrogen supply pipe by a hydrogen pump. In other words, in this fuel cell system, the amount of hydrogen gas consumed is reduced by recovering and reusing hydrogen gas that did not contribute to power generation, but electricity is consumed by the hydrogen pump to return the recovered hydrogen gas to the hydrogen supply pipe, which causes a problem that it is difficult to reduce power generation costs. In addition, the hydrogen pump is expensive, which makes it even more difficult to reduce power generation costs.

[0009] The present invention has been made in consideration of the above problems to be solved, and has as its main object to provide a power generation system and a fuel supply system that can sufficiently reduce the power generation cost. [Means for solving the problem]

[0010] In order to achieve the above object, the power generation system according to claim 1 is a power generation system including a power generation cell, which is configured by stacking and integrating a plurality of flat plate-shaped laminated objects including at least a first separator through which a first gas containing an oxidant is passed, a second separator through which a second gas containing hydrogen is passed, and the membrane electrode assembly disposed between the first separator and the second separator, and capable of generating power by reacting the first gas with the second gas via the membrane electrode assembly, and wherein the second gas is stored in the power generation cell. the second gas discharged from the storage unit is supplied to the second separator; a separation device that separates moisture contained in the second gas that has been passed through the second separator; an ejector that is disposed in the first piping so as to suck in gas from an intake port as the second gas discharged from the storage unit passes through and be able to merge with the second gas discharged from the storage unit; and a second piping that guides the second gas from which moisture has been separated in the separation device to the intake port of the ejector.

[0011] The fuel supply system according to claim 2 is a fuel supply system configured to be capable of supplying the second gas to a power generation cell configured to generate power by reacting the first gas with the second gas via the membrane electrode assembly, the fuel supply system being configured to be capable of supplying the second gas to a power generation cell configured to store the second gas, the power generation cell being configured to stack and integrate a plurality of flat plate-shaped laminated objects including at least a first separator through which a first gas containing an oxidant is passed, a second separator through which a second gas containing hydrogen is passed, and the membrane electrode assembly disposed between the first separator and the second separator. the second gas discharged from the storage unit is supplied to the second separator; a separation device that separates moisture contained in the second gas that has been passed through the second separator; an ejector that is disposed in the first piping so as to be able to suck in gas from an intake port as the second gas discharged from the storage unit passes through and merge with the second gas discharged from the storage unit; and a second piping that guides the second gas from which moisture has been separated in the separation device to the intake port of the ejector. Effect of the Invention

[0012] The power generation system of claim 1 and the fuel supply system of claim 2 include a first pipe that supplies the second gas discharged from the storage unit to a second separator, a separation device that separates moisture contained in the second gas that has passed through the second separator, an ejector arranged in the first pipe so as to suck in gas from an intake port as the second gas discharged from the storage unit passes through and be able to merge with the second gas discharged from the storage unit, and a second pipe that guides the second gas from which moisture has been separated in the separation device to the intake port of the ejector.

[0013] Therefore, according to the power generation system of claim 1 and the fuel supply system of claim 2, by recovering and reusing the unreacted second gas (hydrogen) discharged from the storage unit, not only can the amount of hydrogen consumed for power generation be sufficiently reduced, but also a pump or the like for merging the recovered second gas with the second gas discharged from the storage unit is not required, and no electricity is consumed for the merging, thereby sufficiently reducing the power generation cost. [Brief description of the drawings]

[0014] [Figure 1] 1 is a configuration diagram showing a configuration of a power generation system 1. FIG. [Diagram 2] 2 is an explanatory diagram for explaining the configuration of an ejector 8. FIG. [Diagram 3] FIG. 2 is an explanatory diagram for explaining the configuration of a humidifier 30. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a fuel supply device and a power generation system will be described with reference to the accompanying drawings.

[0016] The power generation system 1 shown in FIG. 1 is configured to generate electricity by reacting gases for power generation (air (atmosphere: oxygen), which is an example of a "first gas containing an oxidant," and hydrogen gas, which is an example of a "second gas containing hydrogen"). Specifically, the power generation system 1 includes a pump 2, pipes 3a to 3c, a gas-liquid separation tank 4, pipes 5a to 5d, a gas-liquid separation tank 6, pipe 7, an ejector 8, pipes 9a and 9b, a fuel cell 10, a hydrogen tank 20, and a humidifier 30. In the power generation system 1 of this example, the components other than the hydrogen tank 20, the pipe 5b, and the humidifier 30 constitute a "power generation system including a power generation cell configured to be capable of generating power by reacting a first gas with a second gas," and the components other than the pump 2, the pipes 3a to 3c, and the fuel cell 10 constitute a "fuel supply system configured to be capable of supplying a second gas to the power generation cell."

[0017] In this case, the fuel cell 10 is an example of a "power generation cell" and includes a power generation stack made up of separator 11, which is an example of a "first separator," separator 12, which is an example of a "second separator," and MEA 13, which is an example of a "membrane electrode assembly," as well as a separator (not shown) for passing a cooling fluid (air or coolant), and end plates (not shown) disposed at both ends in the stacking direction of each laminate. In this example, each plate such as separators 11 and 12, MEA 13, the cooling separator, and the end plates correspond to "plurality of flat plate-shaped laminated objects," and the fuel cell 10 is configured by stacking and integrating these.

[0018] Separator 11 has a groove (not shown) for passing air (atmosphere), and separator 12 has a groove (not shown) for passing hydrogen gas. Both separators 11 and 12 are stacked so that MEA 13 is sandwiched between them, and air flow path 11c is formed by the groove of separator 11 and one surface of MEA 13, and hydrogen flow path 12c is formed by the groove of separator 12 and the other surface of MEA 13. MEA 13 is configured with an electrolyte membrane, a catalyst layer, a gas diffusion layer, and the like. Note that an actual fuel cell 10 is configured with a plurality of the above-mentioned power generation stacks and cooling separators according to the power generation capacity required for power generation system 1, but in order to facilitate understanding of the configuration and operation of power generation system 1, only one power generation stack is illustrated, and illustration and description of cooling separators and end plates are omitted.

[0019] The hydrogen tank 20 is also an example of a "storage section in which a second gas is stored" and is configured to store hydrogen gas generated at a separate location and transported to the installation location of the power generation system 1 (hydrogen tank 20), or hydrogen gas generated by a hydrogen generation device (not shown) installed together with the power generation system 1 at the installation location of the power generation system 1, and to supply this hydrogen gas to the separator 12 of the fuel cell 10 as "second gas: fuel."

[0020] The humidifier 30 is configured to be capable of humidifying the hydrogen gas supplied from the hydrogen tank 20 to the fuel cell 10 (separator 12). Specifically, as shown in FIG. 3, the humidifier 30 includes a sealed container 31 capable of storing water poured in prior to the start of power generation or water supplied from the gas-liquid separation tanks 4, 6 via a pipe 9a, a nozzle 32 disposed at the tip of a pipe 5b that guides the hydrogen gas discharged from the ejector 8 to the humidifier 30, and a number of spheres 33, 33, etc. contained in the sealed container 31, and is configured to be capable of supplying the hydrogen gas humidified by passing it through water to the fuel cell 10 (separator 12) via the pipe 5c. In this case, the spheres 33 are formed in the shape of small spheres of a material and structure that can generate buoyancy with respect to the water stored in the sealed container 31. The humidification of hydrogen gas by the humidifier 30 will be described in detail later.

[0021] On the other hand, the pump 2 pressure-feeds (supplies) air into the air flow path 11c of the separator 11. The pipe 3a is connected to the intake port of the pump 2, the pipe 3b has one end connected to the exhaust port of the pump 2 and the other end connected to the pipe connection part 11a (intake port) of the separator 11, and the pipe 3c has one end connected to the pipe connection part 11b (exhaust port) of the separator 11 and the other end connected to the gas-liquid separation tank 4. Instead of the above-mentioned configuration of the pump 2 and each of the pipes 3a to 3c, the pipe 3a can be directly connected to the pipe connection part 11a of the separator 11, the other end of the pipe 3c can be connected to the intake port of the pump 2, and the exhaust port of the pump 2 can be connected to the gas-liquid separation tank 4 via another pipe (not shown). When such a configuration is adopted, the pump 2 sucks in the air inside the separator 11 (air flow path 11c), thereby sucking (supplying) new air from the pipe 3a to the separator 11 (air flow path 11c), and the air sucked in by the pump 2 (exhaust air from the separator 11) is pressure-fed to the gas-liquid separation tank 4.

[0022] The gas-liquid separation tank 4 is configured to separate the exhaust gas (a mixture of air and water) discharged from the separator 11 and introduced through the pipe 3c into air and water. In this case, when generating electricity in the fuel cell 10, air (oxygen) passing through the separator 11 (air flow path 11c) reacts with hydrogen gas passing through the separator 12 (hydrogen flow path 12c) to generate water in the air flow path 11c, and this water is discharged from the separator 11 together with the exhaust gas (air reacted with hydrogen). Therefore, in the power generation system 1 of this example, a configuration is adopted in which this water is recovered in the gas-liquid separation tank 4 and the recovered water is supplied to the humidifier 30.

[0023] One end of the pipe 5a is connected to the hydrogen tank 20 and the other end is connected to the ejector 8, one end of the pipe 5b is connected to the ejector 8 and the other end is connected to the humidifier 30, one end of the pipe 5c is connected to the humidifier 30 and the other end is connected to a pipe connection part 12a (intake port) of the separator 12, and one end of the pipe 5d is connected to a pipe connection part 12b (exhaust port) of the separator 12 and the other end is connected to the gas-liquid separation tank 6. In this example, the pipes 5a to 5c work together to form "a first pipe that supplies the second gas discharged from the storage part to the second separator."

[0024] The gas-liquid separation tank 6 is an example of a "separation device that separates the moisture contained in the second gas that has been passed through the second separator", and is configured to separate the exhaust gas (a mixture of unreacted hydrogen gas and water) that has been passed through the hydrogen flow path 12c of the separator 12 and discharged from the pipe connection part 12b to the pipe 5d, into hydrogen gas and water.

[0025] In this case, as described below, when hydrogen gas is supplied from the hydrogen tank 20 to the fuel cell 10 (separator 12), the pressure and temperature of the hydrogen gas change successively in the flow path (pipes 5a-5c, ejector 8, and humidifier 30) from the hydrogen tank 20 to the separator 12 and in the separator 12 (hydrogen flow path 12c), which may cause condensation in the flow path and in the separator 12, resulting in liquid moisture (water droplets).

[0026] Moreover, the hydrogen gas discharged from the hydrogen tank 20 is dehumidified to prevent condensation from occurring inside the tank, and its humidity is low. When such low-humidity hydrogen gas is supplied to the fuel cell 10 (separator 12), the MEA 13 dries up and the power generation efficiency decreases, so the power generation system 1 of this example employs a configuration in which the low-humidity hydrogen gas discharged from the hydrogen tank 20 is humidified in a humidifier 30 before being supplied to the fuel cell 10. Here, as will be described in detail later, the power generation system 1 of this example employs a configuration that prevents liquid-phase moisture from being discharged from the humidifier 30 together with the hydrogen gas, but a very small amount of liquid-phase moisture may be discharged together with the hydrogen gas.

[0027] For this reason, when power generation is performed by the power generation system 1, water generated by condensation in the flow paths and separator 12, as described above, and water discharged from the humidifier 30 together with hydrogen gas may be discharged from the pipe connection part 12b together with unreacted hydrogen gas. Therefore, the power generation system 1 of this example employs a configuration in which this water is recovered in the gas-liquid separation tank 6 and the recovered water is supplied to the humidifier 30 for reuse.

[0028] The pipe 7 is an example of "a second pipe for guiding the second gas from which moisture has been separated in the separation device to the intake port of the ejector", and has one end connected to the exhaust port of the gas-liquid separation tank 6 and the other end connected to the inlet 8d of the ejector 8. The ejector 8 is an example of "an ejector arranged in the first pipe so that the gas can be sucked in from the intake port by the passage of the second gas discharged from the storage unit and merged with the second gas discharged from the storage unit", and as shown in Fig. 2, includes a nozzle 8a, a diffuser 8b, a sealed container 8c, and an inlet 8d, and as described above, the nozzle 8a is connected to the hydrogen tank 20 via the pipe 5a, and the diffuser 8b is connected to the humidifier 30 via the pipe 5b.

[0029] In this ejector 8, the inlet 8d (an example of an "intake port") is connected to the inside of the sealed container 8c, and the gas-liquid separation tank 6 is connected to the inside of the sealed container 8c via the piping 7 connected to the inlet 8d. In addition, in this ejector 8, the nozzle 8a and the diffuser 8b are arranged in the sealed container 8c so that the exhaust port of the nozzle 8a and the inlet port of the diffuser 8b face each other while being slightly spaced apart from each other in the sealed container 8c. As a result, in this ejector 8, a negative pressure is generated in the sealed container 8c due to the flow of hydrogen gas (hydrogen gas discharged from the hydrogen tank 20 and moving toward the fuel cell 10) moving at high speed from the nozzle 8a toward the diffuser 8b in the sealed container 8c, and this negative pressure causes the hydrogen gas in the gas-liquid separation tank 6 to be sucked into the sealed container 8c from the inlet 8d via the piping 7, and is joined to the hydrogen gas flowing from the nozzle 8a toward the inlet 8d.

[0030] The pipe 9a is disposed so as to be capable of supplying water separated from the exhaust gas in the gas-liquid separation tanks 4, 6 and stored in the tanks to the humidifier 30. Note that in reality, a valve mechanism and the like that permit / restrict the discharge of water from the gas-liquid separation tanks 4, 6 are disposed in the pipe 9a, but illustrations and descriptions thereof are omitted to facilitate understanding of the configuration of the power generation system 1. The pipe 9b is connected to the gas-liquid separation tank 4 so as to be able to release the separated air into the atmosphere.

[0031] In this power generation system 1, as described above, air (atmosphere: oxygen) and hydrogen gas (hydrogen) supplied from the hydrogen tank 20 are reacted in the fuel cell 10 to generate power. Specifically, when an instruction to start generating power is given by operating an operation unit (not shown), the pump 2 starts pumping air (oxygen). At this time, air sucked in through the pipe 3a is supplied to the separator 11 through the pipe 3b. In parallel with the supply of air to the separator 11, the supply of hydrogen gas from the hydrogen tank 20 is started, and the hydrogen gas discharged from the hydrogen tank 20 is supplied to the separator 12 through the pipe 5a, the ejector 8, the pipe 5b, the humidifier 30, and the pipe 5c. As a result, electricity is generated by the reaction between the air (oxygen) passed through the air flow passage 11c and the hydrogen gas (hydrogen) passed through the hydrogen flow passage 12c.

[0032] In this case, in the power generation system 1 of this example, as described above, in order to prevent low-humidity hydrogen gas discharged from the hydrogen tank 20 from being supplied to the fuel cell 10 (separator 12) and causing drying up of the MEA 13, a configuration is adopted in which the hydrogen gas discharged from the hydrogen tank 20 is humidified in the humidifier 30 and then supplied to the fuel cell 10 (separator 12). Specifically, as shown in FIG. 3, the hydrogen gas supplied through the pipe 5b and discharged from the nozzle 32 into the sealed container 31 absorbs moisture as it rises in the water in the sealed container 31, thereby increasing its relative humidity. In addition, the hydrogen gas that has risen to the vicinity of the water surface passes between the spheres 33, 33, and is discharged to the pipe 5c. As a result, hydrogen gas with a sufficiently high humidity is supplied to the fuel cell 10 (separator 12) through the pipe 5c without causing a situation in which a large amount of water in the sealed container 31 is discharged together with the hydrogen gas.

[0033] Meanwhile, during power generation in the fuel cell 10, about 85% of the hydrogen gas introduced from the pipe connection part 12a to the hydrogen flow path 12c is consumed by reaction with air (oxygen), but the remaining hydrogen gas of about 15% does not react with air (oxygen) and is discharged from the pipe connection part 12b to the pipe 5d. Therefore, the power generation system 1 of this example employs a configuration in which the hydrogen gas (unreacted hydrogen) discharged from the pipe connection part 12b is recovered and the recovered hydrogen gas is merged with the hydrogen gas supplied from the hydrogen tank 20 to the separator 12 (pipe connection part 12a) for reuse, thereby reducing the amount of hydrogen gas (hydrogen) consumed by the entire system.

[0034] In this case, as described above, the hydrogen gas supplied to separator 12 may contain moisture generated by condensation due to changes in pressure and temperature in the flow path from hydrogen tank 20 to separator 12 and in hydrogen flow path 12c, or moisture discharged from ejector 8. For this reason, the hydrogen gas discharged from pipe connection part 12b may contain water droplets, and if such hydrogen gas is reused as is (supplied to separator 12 as is), there is a risk that the amount of moisture flowing from pipe connection part 12a into hydrogen flow path 12c will be very large.

[0035] In such a state, the water droplets that have flowed into the hydrogen flow path 12c act as resistance to the passage of hydrogen gas, and it may become difficult to pass a sufficient amount of hydrogen gas to react with air (oxygen). Therefore, in the power generation system 1 of this example, a configuration is adopted in which the moisture discharged together with hydrogen gas from the pipe connection part 12b to the pipe 5d is separated into water and hydrogen gas in the gas-liquid separation tank 6, and the liquid phase hydrogen gas containing almost no moisture is merged with the hydrogen gas supplied from the hydrogen tank 20 and supplied to the separator 12.

[0036] In the power generation system 1 of this embodiment, which supplies hydrogen gas discharged from the hydrogen tank 20 to the fuel cell 10 to generate power, the pressure of the hydrogen gas in the pipe 5a (the discharge pressure of the hydrogen gas from the hydrogen tank 20) ​​is high, at about 1.0 MPa. Therefore, in the power generation system 1 of this embodiment, as shown in Fig. 2, the high-pressure hydrogen gas discharged from the hydrogen tank 20 is ejected at high speed from the nozzle 8a of the ejector 8 toward the diffuser 8b as shown by the arrow A, thereby generating negative pressure between the nozzle 8a and the diffuser 8b, and this negative pressure is used to merge the hydrogen gas ejected from the nozzle 8a (the hydrogen gas discharged from the hydrogen tank 20) ​​with the hydrogen gas in the sealed container 8c as shown by the arrow Ba, and the hydrogen gas is discharged from the diffuser 8b to the pipe 5b as shown by the arrow C.

[0037] In this case, the gas-liquid separation tank 6 is connected to the inlet 8d of the sealed container 8c via the pipe 7. Therefore, the hydrogen gas in the sealed container 8c is discharged from the diffuser 8b to the pipe 5b together with the hydrogen gas discharged from the hydrogen tank 20, and the hydrogen gas discharged from the pipe connection part 12b and from which moisture has been separated in the gas-liquid separation tank 6 is sucked into the ejector 8 (sealed container 8c) via the pipe 7 and merged with the hydrogen gas from the hydrogen tank 20 as described above. As a result, not only the hydrogen gas discharged from the hydrogen tank 20 but also the hydrogen gas discharged from the separator 12 and from which moisture has been removed in the gas-liquid separation tank 6 are used as hydrogen gas for power generation, so that the amount of hydrogen gas consumed by the power generation system 1 is sufficiently reduced.

[0038] Meanwhile, by continuing power generation in the fuel cell 10 as described above, moisture contained in the exhaust gas from the separator 11 is separated and stored in the gas-liquid separation tank 4, and moisture contained in the exhaust gas from the separator 12 is separated and stored in the gas-liquid separation tank 6. This water is supplied to the humidifier 30 from the gas-liquid separation tanks 4, 6 via the pipe 9a as water for humidifying hydrogen gas in the humidifier 30. As a result, the hydrogen gas is humidified by the supplied water in the humidifier 30, and hydrogen gas of an appropriate humidity that does not cause drying up is continuously supplied to the separator 12. Thereafter, the power generation by the power generation system 1 continues as described above until an instruction to end power generation is given.

[0039] Thus, this power generation system 1 includes pipes 5a-5c that supply hydrogen gas discharged from the hydrogen tank 20 to the separator 12, a gas-liquid separation tank 6 that separates moisture contained in the hydrogen gas that has passed through the separator 12, an ejector 8 disposed between pipes 5a, 5b so that hydrogen gas discharged from the hydrogen tank 20 can be sucked into the sealed container 8c from an inlet 8d (intake port) through the passage of hydrogen gas discharged from the hydrogen tank 20 and merged with the hydrogen gas discharged from the hydrogen tank 20, and a pipe 7 that guides the hydrogen gas from which moisture has been separated in the gas-liquid separation tank 6 to the inlet 8d of the ejector 8.

[0040] Therefore, with this power generation system and fuel supply system, by recovering and reusing the unreacted hydrogen gas discharged from the separator 12, not only can the amount of hydrogen gas consumed for power generation be sufficiently reduced, but also a pump or the like is not required to combine the recovered hydrogen gas with the hydrogen gas discharged from the hydrogen tank 20, and no electricity is consumed to combine the gases, thereby significantly reducing power generation costs.

[0041] The configurations of the "power generation system" and the "fuel supply system" are not limited to the example configuration of the power generation system 1 described above.

[0042] For example, the configuration of the power generation system 1 including the hydrogen tank 20 (hydrogen gas supply source) has been described as an example, but the configuration of the present invention can also be applied to a "power generation system" that generates power using hydrogen gas supplied from a "storage unit" serving as an external device instead of the hydrogen tank 20. The configuration of the present invention can also be applied to a "fuel supply system" that supplies hydrogen gas as fuel to a power generation unit serving as an external device similar to the pump 2, pipes 3a-3c, and fuel cell 10. Furthermore, the configuration has been described as an example in which the water recovered in the gas-liquid separation tanks 4, 6 is used to humidify the hydrogen gas in the humidifier 30, but a "humidifier" that humidifies the hydrogen gas without using the water discharged from the separators 11 and 12 can also be employed. [Explanation of symbols]

[0043] 1. Power generation system 2. Pump 3a~3c, 5a~5d, 7, 9a, 9b Piping 4,6 Gas-liquid separation tank 8 Ejector 8a Nozzle 8b Diffuser 8c airtight container 8d Introduction 10 Fuel Cell 11,12 Separator 11a, 11b, 12a, 12b Piping connection parts 11c Air passage 12c Hydrogen flow path 13 MEA 20 Hydrogen Tank 30 Humidifier 31 Airtight containers 32 Nozzles 33 Sphere

Claims

1. A power generation system including a power generation cell which is configured to generate power by stacking and integrating a first separator through which a first gas containing an oxidant is passed, a second separator through which a second gas containing hydrogen is passed, and a plurality of flat plate-like laminated objects including at least the membrane electrode assembly disposed between the first separator and the second separator, and which is capable of generating power by reacting the first gas with the second gas via the membrane electrode assembly, a first pipe that supplies the second gas discharged from a storage unit in which the second gas is stored to the second separator; a separation device that separates moisture contained in the second gas that has passed through the second separator; an ejector disposed in the first pipe so as to suck in gas from an intake port by the passage of the second gas discharged from the storage unit and to be able to merge with the second gas discharged from the storage unit; a second pipe that guides the second gas from which moisture has been separated in the separation device to the intake port of the ejector.

2. A fuel supply system comprising a plurality of flat plate-like laminated objects, each of which includes at least a first separator through which a first gas containing an oxidant is passed, a second separator through which a second gas containing hydrogen is passed, and a membrane electrode assembly disposed between the first separator and the second separator, stacked and integrated together, and configured to supply the second gas to a power generation cell configured to generate power by reacting the first gas with the second gas via the membrane electrode assembly, a storage unit that stores the second gas; a first pipe that supplies the second gas discharged from the storage unit to the second separator; a separation device that separates moisture contained in the second gas that has passed through the second separator; an ejector disposed in the first pipe so as to suck in gas from an intake port by the passage of the second gas discharged from the storage unit and to be able to merge with the second gas discharged from the storage unit; a second pipe that guides the second gas from which moisture has been separated in the separation device to the intake port of the ejector.

Images