JP2004071471A - Fuel cell system - Google Patents

Abstract

It is necessary to realize safe operation of a polymer electrolyte fuel cell with lower power consumption, lower cost, and smaller size.
A fuel cell (11) through which fuel gas flows in from a fuel gas inlet and flows out of a fuel gas outlet, and a fuel gas inlet for allowing fuel gas to flow through the fuel cell (11). Passage 13 for bypassing between the fuel gas outlet and the fuel gas, a switching valve 14 for switching whether the fuel gas flows through the fuel cell 11 or the bypass passage 13, And a check valve 15 provided on the fuel gas outlet side to prevent the fuel gas from flowing back to the fuel cell 11 when the switching is performed so that the fuel gas flows through the fuel cell 11. System.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a fuel cell system for generating electric power using a polymer electrolyte fuel cell.
[0002]
[Prior art]
Hereinafter, the configuration and operation of a conventional polymer electrolyte fuel cell system will be described with reference to the drawings.
[0003]
As shown in FIG. 10, which is a configuration diagram showing a conventional polymer electrolyte fuel cell system, the conventional polymer electrolyte fuel cell system includes a fuel cell 1 that generates power using a fuel gas and an oxidant gas, Each path includes a fuel gas supply / discharge system, an air supply / discharge system as an oxidant, and a fuel cell cooling system.
[0004]
In the fuel gas supply / discharge system path, a fuel processor 2 that steam reforms a raw material gas such as natural gas to generate a hydrogen-rich fuel gas on the fuel gas supply side, and a humidifier 3 that humidifies the fuel gas. Is provided. Further, a condenser 4 and a condensed water tank 5 for cooling the exhaust fuel gas discharged from the fuel cell 1 on the discharge side of the fuel gas and condensing water vapor contained therein, and combusting a combustion gas such as natural gas and the exhaust fuel gas. A burner 6 for heating the fuel processor 2 and a combustion fan 7 for supplying air for combustion are provided. Furthermore, a bypass 8 for bypassing the fuel cell 1, a switching valve 9 for switching the fuel gas flow path to the fuel cell 1 or the bypass 8 and a backflow of the fuel gas flowing through the bypass 8 are prevented. Opening / closing valve 10 for
[0005]
The fuel gas generated by the fuel processor 2 contains water vapor, carbon dioxide, and a trace amount of carbon monoxide in addition to hydrogen. The fuel gas generated by the fuel processor 2 is humidified by the humidifier 3 using water supplied from the condensed water tank 5 or the like. The humidified fuel gas is sent to the condenser 4 via the bypass 8 by the switching valve 9 when the fuel gas contains a large amount of carbon monoxide at the time of starting the system or the like.
[0006]
At this time, the on-off valve 10 is closed to prevent the backflow of the fuel gas containing a large amount of carbon monoxide.
[0007]
Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the on-off valve 10 is opened, the gas is supplied to the fuel cell 1 by the switching valve 9, and power is generated together with the supplied air.
[0008]
This is because the polymer electrolyte fuel cell system operates at a very low temperature of about 80 ° C. as compared with the case of the phosphoric acid type (about 200 ° C.). Although there is no problem if a fuel gas containing several percent of carbon monoxide is supplied to the fuel cell 1, in the case of the polymer electrolyte fuel cell, the fuel gas containing several tens ppm or more of carbon monoxide is used. This is because even if the fuel is supplied to the fuel cell 1, the catalyst in the fuel cell 1 is poisoned and the power generation performance is deteriorated.
[0009]
From the fuel cell 1, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged exhaust gas flows through the on-off valve 10, is cooled by the condenser 4 to dehumidify the contained water vapor, and then supplied to the burner 6. The burner 6 burns a combustion gas such as natural gas and an exhaust fuel gas, and maintains the temperature of the fuel processor 2 at a temperature (about 700 ° C.) required to generate a hydrogen-rich fuel gas from a raw material gas.
[0010]
Similarly, the fuel gas that has passed through the bypass 8 by the switching valve 9 at the time of startup is also supplied to the burner 6 after being dehumidified by the condenser 4, and is burned together with the combustion gas or only with the fuel gas.
[0011]
The water dehumidified by the condenser 4 is stored in a condensed water tank 5 and supplied to the humidifier 3 and the like as humidified water. Sometimes, it is supplied to the fuel processor 2 as water for steam reforming.
[0012]
At the time of start-up, all the fuel gas exiting the humidifier 3 passes through the bypass 8 by the switching valve 9 and is then dehumidified by the condenser 4. In addition, the fuel gas containing a large amount of carbon monoxide via the bypass passage 8 is prevented from flowing back to the fuel cell 1 by closing the on-off valve 10.
[0013]
[Problems to be solved by the invention]
However, there has been a problem that an electromagnetic valve or a motor-operated valve must be used as the on-off valve 10 of such a conventional polymer electrolyte fuel cell system.
[0014]
More specifically, since the operation of such an on-off valve requires electric power, power consumption increases when the solenoid valve is kept open or closed or when the electric valve is opened and closed. Further, the cost increases due to an increase in the number of parts, and the system size increases due to the provision of the on-off valve. Further, the on / off valve may be fixed / closed due to electrical / mechanical failure, and the pressure of the fuel cell 1 and the fuel processor 2 may increase.
[0015]
An object of the present invention is to provide a fuel cell system capable of realizing safe operation of a polymer electrolyte fuel cell with lower power consumption, lower cost, and smaller size in consideration of the above conventional problems. Things.
[0016]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a fuel cell in which fuel gas flows from a fuel gas inlet and flows out of a fuel gas outlet,
A bypass passage for bypassing between the fuel gas inlet and the fuel gas outlet, so that the fuel gas can flow by bypassing the fuel cell;
Switching means for switching whether the fuel gas flows through the fuel cell or the bypass path,
A check valve provided on the fuel gas outlet side for preventing the fuel gas from flowing back to the fuel cell side when the switching is performed so that the fuel gas flows through the bypass passage. And a fuel cell system comprising:
[0017]
In a second aspect of the present invention, the check valve includes a valve body for preventing the fuel gas from flowing back to the fuel cell side, and the switching is performed such that the fuel gas flows through the bypass passage. A fuel cell system according to the first aspect of the present invention, comprising: a valve seat against which the valve element is pressed when the fuel cell system is turned off.
[0018]
A third aspect of the present invention is the fuel cell system according to the second aspect of the present invention, wherein the pressing of the valve body is performed using a predetermined elastic body.
[0019]
In a fourth aspect of the present invention, the valve body is mounted on the valve seat on the basis of a vertical direction,
In the fuel cell system according to the second aspect of the present invention, the pressing of the valve body is performed using the weight of the valve body.
[0020]
A fifth invention is the fuel cell system according to the first invention, further comprising a first tank provided between the fuel gas outlet and the check valve for storing condensed water. .
[0021]
A sixth invention is a first tank water level detecting means for detecting a water level of the first tank,
A drain valve provided in the first tank for draining water stored in the first tank based on a detection result by the first tank water level detecting means; 1 is a fuel cell system of the present invention.
[0022]
A seventh aspect of the present invention provides a burner to which a fuel gas flowing through the fuel cell or flowing through the bypass path is supplied,
The fuel cell system according to the fifth or sixth aspect of the present invention, further comprising a second tank provided between the end point of the bypass passage and the burner for storing condensed water.
[0023]
Eighth invention is a second tank water level detecting means for detecting a water level of the second tank,
A second drain valve provided in the second tank for draining at least the water stored in the second tank, based on the result of the detection by at least the second tank water level detecting means. 21 is a fuel cell system according to a seventh aspect of the present invention.
[0024]
A ninth aspect of the present invention provides a communication path for communicating the first tank and the second tank,
First tank water level detection means for detecting the water level of the first tank,
A seventh drainage valve provided in the communication passage for draining water stored in the first tank based on a detection result by the first tank water level detection means. Or, the fuel cell system according to the eighth aspect of the present invention.
[0025]
A tenth aspect of the present invention is a communication passage that communicates the first tank and the second tank such that a water level of the second tank is higher than a water level of the first tank.
Second tank water level detection means for detecting the water level of the second tank,
The drainage of water stored in the first tank and the drainage of water stored in the second tank are performed based on the detection result by the second tank water level detection means, A seventh fuel cell system according to the present invention, further comprising a third drain valve provided in the tank.
[0026]
An eleventh invention is the fuel cell system according to the seventh invention, further comprising a condenser provided between the end point of the bypass and the second tank for condensing the water.
[0027]
The twelfth invention is the fuel cell system according to the first invention, wherein the check valve is configured using a water-repellent material.
[0028]
A thirteenth invention is the fuel cell system according to the twelfth invention, wherein the water-repellent material is a fluorine-based material.
[0029]
Embodiment
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0030]
(Embodiment 1)
First, the configuration of the polymer electrolyte fuel cell system of the present embodiment will be described mainly with reference to FIG. FIG. 1 is a configuration diagram illustrating a polymer electrolyte fuel cell system according to Embodiment 1 of the present invention.
[0031]
The polymer electrolyte fuel cell system according to the present embodiment includes a polymer electrolyte fuel cell 11 that generates electric power using a fuel gas and an oxidant gas, and a hydrogen-rich fuel gas obtained by steam reforming a raw material gas such as natural gas. A fuel processor 12 for generating fuel gas, a bypass 13 for bypassing the fuel cell 11 in a fuel gas flow path through which the fuel gas flows, and a switch for switching the fuel gas flow between the fuel cell 11 and the bypass 13 A valve 14, a check valve 15 'for preventing the fuel gas flowing through the bypass passage 13 from flowing back to the fuel cell 11, and a fuel gas flowing through the bypass passage 13 or the exhaust fuel gas discharged from the fuel cell 11 And a burner 16 for burning the fuel and heating the fuel processor.
[0032]
As shown in FIG. 2, the check valve 15 ′ includes a valve seat 17, a valve body 18, a sealing material 19 for preventing flow when the valve seat 17 and the valve body 18 are in contact with each other, and a valve seat 18. A spring 20 that presses the valve 17 and a guide 21 that stabilizes the drive shaft of the valve element 18 are provided.
[0033]
Next, the operation of the polymer electrolyte fuel cell system according to the present embodiment will be described.
[0034]
In the fuel processor 12, in order to promote a reforming reaction for generating a hydrogen-rich fuel gas from a raw material gas such as a natural gas, the fuel is heated by a burner 16 at a temperature of about 700 ° C. At the same time, the fuel processor 12 has a function of removing carbon monoxide contained in the fuel gas to a concentration that does not damage the catalyst of the fuel cell 11.
[0035]
When the fuel gas contains a large amount of carbon monoxide at the time of starting the system, the switching valve 14 closes the fuel cell 11 and opens the bypass 13. At this time, the fuel gas discharged from the fuel processor 12 is guided to the bypass 13 by the switching valve 14 and bypasses the fuel cell 11. The fuel gas flowing through the bypass passage 13 flows only in the direction of the burner 16 by the check valve 15 '. The fuel gas supplied to the burner 16 is burned together with the combustion gas or only with the fuel gas.
[0036]
At this time, the check valve 15 ′ is configured such that the valve body 18 is pressed against the valve seat 17 by the spring 20 and the fuel gas flow path is closed by the sealing member 19, so that the fuel gas flows back to the fuel cell 11. Has been prevented.
[0037]
Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the switching valve 14 opens the fuel cell 11 and closes the bypass 13. The fuel gas discharged from the fuel processor 12 is supplied to the fuel cell 11 by the switching valve 14, and generates electric power together with the supplied air. From the fuel cell 11, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged exhaust fuel gas is supplied to the burner 16 after flowing through the check valve 15 ', and is burned together with the combustion gas or only with the exhaust fuel gas.
[0038]
At this time, in the check valve 15 ′, the fuel gas presses the valve element 18 with a pressure larger than the pressure by the spring 20, and the valve element 18 slides by the guide 21, so that the fuel gas flow path is secured.
[0039]
Therefore, when the configuration of the polymer electrolyte fuel cell system according to the present embodiment is adopted, the fuel gas containing a large amount of carbon monoxide, such as at the time of starting the system, is supplied to the bypass passage 13, the switching valve 14, and the check valve 15 '. , Does not flow into / back flow into the fuel cell 11. Thus, it is possible to prevent the catalyst of the fuel cell 11 from being poisoned by carbon monoxide which is largely contained in the fuel gas when the system is started.
[0040]
In the polymer electrolyte fuel cell system according to the present embodiment, a check valve 15 'is used to prevent backflow. No electric power is used to open and close the check valve 15 '. Further, the structure of the check valve 15 'is extremely simple as shown in FIG. 2, so that the size is small and the cost is low.
[0041]
That is, by employing the configuration of the polymer electrolyte fuel cell system in the present embodiment, a polymer electrolyte fuel capable of safe operation without lowering power consumption, lower cost, smaller size, and not poisoning the catalyst of the fuel cell can be obtained. A battery system can be realized.
[0042]
Thus, in the fuel cell system including the bypass passage that bypasses the inlet / outlet of the fuel cell in the fuel gas flow path through which the fuel gas flows, and the flow path switching valve that switches the fuel gas flow path between the fuel cell side and the bypass path side, With a non-return valve that prevents the backflow of fuel gas flowing into the fuel cell into the fuel cell, the solid height allows for safer operation with lower power consumption, lower cost, smaller size, and less poisoning of the fuel cell catalyst. A molecular fuel cell system can be realized.
[0043]
The switching valve 14 corresponds to the switching means of the present invention, and the spring 20 corresponds to the elastic body of the present invention.
[0044]
(Embodiment 2)
First, the configuration of the polymer electrolyte fuel cell system of the present embodiment will be described mainly with reference to FIG. FIG. 3 is a configuration diagram illustrating a polymer electrolyte fuel cell system according to Embodiment 2 of the present invention.
[0045]
The configuration of the polymer electrolyte fuel cell system of the present embodiment is similar to the configuration of the polymer electrolyte fuel cell system of Embodiment 1 described above.
[0046]
However, in the polymer electrolyte fuel cell system of the present embodiment, the check valve 15 is installed in the vertical direction, and the flow direction of the exhaust fuel gas discharged from the fuel cell 11 to the check valve is from below. Looking up.
[0047]
FIG. 4 shows a configuration diagram of the check valve 15 in the present embodiment. The check valve 15 according to the present embodiment differs from the check valve 15 ′ according to the first embodiment (see FIG. 1) in that a spring 20 (see FIG. 2) for pressing the valve body 18 against the valve seat 17 is removed. See).
[0048]
Next, the operation of the polymer electrolyte fuel cell system according to the present embodiment will be described.
[0049]
In the fuel processor 12, in order to promote a reforming reaction for generating a hydrogen-rich fuel gas from a raw material gas such as a natural gas, the fuel is heated by a burner 16 at a temperature of about 700 ° C. At the same time, the fuel processor 12 has a function of removing carbon monoxide contained in the fuel gas to a concentration that does not damage the catalyst of the fuel cell 11.
[0050]
When the fuel gas contains a large amount of carbon monoxide at the time of starting the system, the switching valve 14 closes the fuel cell 11 and opens the bypass 13. At this time, the fuel gas discharged from the fuel processor 12 is guided to the bypass 13 by the switching valve 14 and bypasses the fuel cell 11. The fuel gas flowing through the bypass 13 flows through the check valve 15 only in the direction of the burner 16. The fuel gas supplied to the burner 16 is burned together with the combustion gas or only with the fuel gas.
[0051]
At this time, the check valve 15 has the valve body 18 pressed against the valve seat 17 by the self-weight of the valve body 18 and the back pressure from the downstream of the check valve 15, and the fuel gas flow path is closed by the seal member 19. Therefore, backflow of the fuel gas to the fuel cell 11 is prevented.
[0052]
Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the switching valve 14 opens the fuel cell 11 and closes the bypass 13. The fuel gas discharged from the fuel processor 12 is supplied to the fuel cell 11 by the switching valve 14, and generates electric power together with the supplied air. From the fuel cell 11, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged exhaust fuel gas flows through the check valve 15 and is then supplied to the burner 16 and is burned together with the combustion gas or only with the exhaust fuel gas.
[0053]
At this time, the fuel gas pushes the valve element 18 with a pressure larger than the pressure due to the weight of the valve element 18 and the valve element 18 slides by the guide 21, so that the fuel gas flow path is secured.
[0054]
Therefore, when the configuration of the polymer electrolyte fuel cell system according to the present embodiment is adopted, the check valve 15 closes due to its own weight of the valve element 18 and the reverse pressure from downstream of the check valve 15. Therefore, the spring 20 for closing the valve as shown in FIG. 2 is not required. Further, since the valve body 18 can also be reduced in weight, the pressure loss can be further reduced even in the case of a forward flow.
[0055]
That is, when the configuration of the polymer electrolyte fuel cell system according to the present embodiment is adopted, in addition to the operation shown in the first embodiment, a simpler check valve configuration is possible, and the pressure of the fuel gas flow path is increased. A polymer electrolyte fuel cell system capable of reducing loss can be realized.
[0056]
In FIG. 4, the valve element 18 has a complicated shape, and the sealing material 19 is incorporated on the valve element 18 side. However, the same effect can be obtained even if the valve element 18 is spherical.
[0057]
In addition, the same effect can be obtained by incorporating the sealing material 19 on the valve seat 17 side.
[0058]
Thus, a simpler check valve configuration is possible by installing the check valve in the vertical direction and by allowing the exhaust fuel gas discharged from the fuel cell to flow from the bottom to the top of the check valve. Thus, a polymer electrolyte fuel cell system capable of reducing the pressure loss in the fuel gas flow path can be realized.
[0059]
(Embodiment 3)
First, the configuration of the polymer electrolyte fuel cell system according to the present embodiment will be described mainly with reference to FIG. FIG. 5 is a configuration diagram illustrating a polymer electrolyte fuel cell system according to Embodiment 3 of the present invention.
[0060]
The configuration of the polymer electrolyte fuel cell system of the present embodiment is similar to the configuration of the polymer electrolyte fuel cell system of Embodiment 2 described above.
[0061]
However, the polymer electrolyte fuel cell system of the present embodiment includes a drain tank 22 for storing drain water condensed upstream of the check valve 15 in a fuel gas flow path upstream of the check valve 15, and a drain tank 22. It further includes an electromagnetic valve 23 'for discharging drain water stored in the tank, and a water level sensor 24 for detecting a water level. That is, the drain tank 22, the solenoid valve 23 ', and the water level sensor 24 are the drain mechanism in the present embodiment.
[0062]
Next, the operation of the polymer electrolyte fuel cell system according to the present embodiment will be described.
[0063]
In the fuel processor 12, in order to promote a reforming reaction for generating a hydrogen-rich fuel gas from a raw material gas such as a natural gas, the fuel is heated by a burner 16 at a temperature of about 700 ° C. At the same time, the fuel processor 12 has a function of removing carbon monoxide contained in the fuel gas to a concentration that does not damage the catalyst of the fuel cell 11.
[0064]
When the fuel gas contains a large amount of carbon monoxide at the time of starting the system, the switching valve 14 closes the fuel cell 11 and opens the bypass 13. At this time, the fuel gas discharged from the fuel processor 12 is guided to the bypass 13 by the switching valve 14 and bypasses the fuel cell 11. The fuel gas flowing through the bypass 13 flows through the check valve 15 only in the direction of the burner 16. The fuel gas supplied to the burner 16 is burned together with the combustion gas or only with the fuel gas.
[0065]
At this time, the check valve 15 has the valve body 18 pressed against the valve seat 17 by the self-weight of the valve body 18 and the back pressure from the downstream of the check valve 15, and the fuel gas flow path is closed by the seal member 19. Therefore, backflow of the fuel gas to the fuel cell 11 is prevented.
[0066]
Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the switching valve 14 opens the fuel cell 11 and closes the bypass 13. The fuel gas discharged from the fuel processor 12 is supplied to the fuel cell 11 by the switching valve 14, and generates electric power together with the supplied air. From the fuel cell 11, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged exhaust fuel gas flows through the check valve 15 and is then supplied to the burner 16 and is burned together with the combustion gas or only with the exhaust fuel gas.
[0067]
At this time, the fuel gas pushes the valve element 18 with a pressure larger than the pressure due to the weight of the valve element 18 and the valve element 18 slides by the guide 21, so that the fuel gas flow path is secured.
[0068]
On the other hand, the drain water condensed upstream of the check valve 15 is separated before the check valve 15 and stored in the drain tank 22. The drain tank 22 has a water level sensor 24 for detecting the water level in the drain tank 22. When the water level rises and exceeds a first certain threshold value X1, the solenoid valve 23 'is opened by control to drain the drain water. When the water level falls and falls below a second certain threshold value X2, the solenoid valve 23 'is closed to stop drain water discharge.
[0069]
Therefore, in the configuration of the polymer electrolyte fuel cell system according to the present embodiment, the drain water condensed upstream of the check valve 15 is separated from the fuel gas upstream of the check valve 15, so that the check valve Only the fuel gas flows through 15. As a result, unstable supply (for example, pulsation) of the fuel gas due to the condensed water remaining in the fuel gas flow path can be prevented, and the operation of the check valve 15 can be performed more stably. (Even if the flow of the fuel gas is vertically upward in the vicinity of the check valve 15, the path will not be blocked by the condensed water).
[0070]
That is, with the configuration of the polymer electrolyte fuel cell system according to the present embodiment, in addition to the action described in the second embodiment, the solid polymer fuel cell system that enables more stable fuel gas supply and stable operation of the check valve Type fuel cell system can be realized.
[0071]
Thus, by providing a drain mechanism for storing and discharging water condensed upstream of the check valve in the fuel gas flow path upstream of the check valve, more stable fuel gas supply and stable operation of the check valve are provided. And a polymer electrolyte fuel cell system that enables the above.
[0072]
The drain tank 22 corresponds to the first tank of the present invention, the solenoid valve 23 'corresponds to the drain valve of the present invention, and the water level sensor 24 corresponds to the first tank water level detecting means of the present invention.
[0073]
(Embodiment 4)
First, the configuration of the polymer electrolyte fuel cell system of the present embodiment will be described mainly with reference to FIG. FIG. 6 is a configuration diagram illustrating a polymer electrolyte fuel cell system according to Embodiment 4 of the present invention.
[0074]
The configuration of the polymer electrolyte fuel cell system of the present embodiment is similar to the configuration of the polymer electrolyte fuel cell system of Embodiment 3 described above.
[0075]
However, the polymer electrolyte fuel cell system according to the present embodiment includes a first drain tank 22 for storing water condensed in a fuel gas flow path upstream of the check valve 15, and a water level sensor 24 for detecting a water level. A second drain tank 25 that stores drain water condensed in the fuel gas flow path in front of the burner 16, a communication path 26 that communicates the first drain tank 22 and the second drain tank 25, It further includes an electromagnetic valve 23 for opening and closing the communication passage 26, an electromagnetic valve 27 for discharging drain water, and a water level sensor 28 for detecting a water level inside the second drain tank 25.
[0076]
Next, the operation of the polymer electrolyte fuel cell system according to the present embodiment will be described.
[0077]
In the fuel processor 12, in order to promote a reforming reaction for generating a hydrogen-rich fuel gas from a raw material gas such as a natural gas, the fuel is heated by a burner 16 at a temperature of about 700 ° C. At the same time, the fuel processor 12 has a function of removing carbon monoxide contained in the fuel gas to a concentration that does not damage the catalyst of the fuel cell 11.
[0078]
When the fuel gas contains a large amount of carbon monoxide at the time of starting the system, the switching valve 14 closes the fuel cell 11 and opens the bypass 13. At this time, the fuel gas discharged from the fuel processor 12 is guided to the bypass 13 by the switching valve 14 and bypasses the fuel cell 11. The fuel gas flowing through the bypass 13 flows through the check valve 15 only in the direction of the burner 16. The fuel gas supplied to the burner 16 is burned together with the combustion gas or only with the fuel gas.
[0079]
At this time, the check valve 15 has the valve body 18 pressed against the valve seat 17 by the self-weight of the valve body 18 and the back pressure from the downstream of the check valve 15, and the fuel gas flow path is closed by the seal member 19. Therefore, backflow of the fuel gas to the fuel cell 11 is prevented.
[0080]
Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the switching valve 14 opens the fuel cell 11 and closes the bypass 13. The fuel gas discharged from the fuel processor 12 is supplied to the fuel cell 11 by the switching valve 14, and generates electric power together with the supplied air. From the fuel cell 11, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged exhaust fuel gas flows through the check valve 15 and is then supplied to the burner 16 and is burned together with the combustion gas or only with the exhaust fuel gas.
[0081]
At this time, the fuel gas pushes the valve element 18 with a pressure larger than the pressure due to the weight of the valve element 18 and the valve element 18 slides by the guide 21, so that the fuel gas flow path is secured.
[0082]
On the other hand, the drain water condensed upstream of the check valve 15 is separated before the check valve 15 and stored in the first drain tank 22.
[0083]
Drain water condensed in the fuel gas flow path before the burner 16 is separated before the burner 16 and stored in the second drain tank 25.
[0084]
The first drain tank 22 has a water level sensor 24 for detecting the water level in the first drain tank 22. When the water level rises and exceeds a first certain threshold value X1, the solenoid valve 23 is opened by control. The drain water is discharged to the second drain tank 25 via the communication passage 26. When the water level falls and falls below a second certain threshold value X2, the solenoid valve 23 is closed to stop the drain water discharge.
[0085]
The second drain tank 25 has a water level sensor 28 for detecting the water level of the second drain tank 25. When the water level rises and exceeds a first certain threshold value X3, the solenoid valve 27 is opened by control. As a result, the drain water is discharged or passed through a water treatment device (not shown) and then supplied to a humidifier (not shown) in the system or a reformer (not shown) of the fuel processor 12. When the water level falls and falls below a second certain threshold value X4, the electromagnetic valve 27 is closed to stop drainage of the drain water from the second drain tank 25.
[0086]
Therefore, in the configuration of the polymer electrolyte fuel cell system according to the present embodiment, the drain water condensed upstream of the check valve 15 is separated from the fuel gas upstream of the check valve 15, so that the check valve Only the fuel gas flows through 15. As a result, unstable supply (for example, pulsation) of the fuel gas due to the condensed water remaining in the fuel gas flow path can be prevented, and the operation of the check valve 15 can be performed more stably. It becomes.
[0087]
Further, only by opening and closing the solenoid valve 27, the drain water of the first and second drain tanks 22 and 25 is effectively discharged, or after the water is passed through a water treatment device (not shown), the humidifier (see FIG. (Not shown) or a reformer (not shown) of the fuel processor 12. Thereby, the drain water condensed in the fuel gas flow path can be centrally managed.
[0088]
That is, with the configuration of the polymer electrolyte fuel cell system according to the present embodiment, in addition to the action described in the third embodiment, the solid polymer fuel cell system can easily manage drain water condensed in the fuel gas flow path. A polymer fuel cell system can be realized.
[0089]
Thus, in a polymer electrolyte fuel cell system for supplying exhaust fuel gas to a burner of a fuel processor, a first drain tank for storing water condensed in a fuel gas flow path upstream of a check valve; A second drain tank that stores condensed water in the exhaust fuel gas and a drain mechanism that has a discharge mechanism that discharges the condensed water. The first drain tank and the second drain tank are communicated with each other. Further, it is possible to realize a polymer electrolyte fuel cell system capable of easily managing drain water condensed in the fuel gas flow path.
[0090]
The solenoid valve 23 corresponds to the first drain valve of the present invention, the drain tank 25 corresponds to the second tank of the present invention, the solenoid valve 27 corresponds to the second drain valve of the present invention, and the water level sensor 28 This corresponds to the second tank water level detecting means of the present invention.
[0091]
(Embodiment 5)
First, the configuration of the polymer electrolyte fuel cell system of the present embodiment will be described mainly with reference to FIG. FIG. 7 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 5 of the present invention.
[0092]
The configuration of the polymer electrolyte fuel cell system according to the present embodiment is similar to the configuration of the polymer electrolyte fuel cell system according to Embodiment 4 described above.
[0093]
However, the polymer electrolyte fuel cell system of the present embodiment does not include the solenoid valve 23 (see FIG. 6) and the water level sensor 24 (see FIG. 6). Instead, the second threshold value X4 of the water level sensor 28 indicates that the water pressure that is larger than the pressure difference between the gases present in the first drain tank 22 and the second drain tank 25 is larger than the communication pressure between the communication passage 26 and the second drain tank 25. It is set to be sufficiently large so as to cover the connecting portion with the above.
[0094]
Next, the operation of the polymer electrolyte fuel cell system according to the present embodiment will be described.
[0095]
In the fuel processor 12, in order to promote a reforming reaction for generating a hydrogen-rich fuel gas from a raw material gas such as a natural gas, the fuel is heated by a burner 16 at a temperature of about 700 ° C. At the same time, the fuel processor 12 has a function of removing carbon monoxide contained in the fuel gas to a concentration that does not damage the catalyst of the fuel cell 11.
[0096]
When the fuel gas contains a large amount of carbon monoxide at the time of starting the system, the switching valve 14 closes the fuel cell 11 and opens the bypass 13. At this time, the fuel gas discharged from the fuel processor 12 is guided to the bypass 13 by the switching valve 14 and bypasses the fuel cell 11. The fuel gas flowing through the bypass 13 flows through the check valve 15 only in the direction of the burner 16. The fuel gas supplied to the burner 16 is burned together with the combustion gas or only with the fuel gas.
[0097]
At this time, the check valve 15 has the valve body 18 pressed against the valve seat 17 by the self-weight of the valve body 18 and the back pressure from the downstream of the check valve 15, and the fuel gas flow path is closed by the seal member 19. Therefore, backflow of the fuel gas to the fuel cell 11 is prevented.
[0098]
Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the switching valve 14 opens the fuel cell 11 and closes the bypass 13. The fuel gas discharged from the fuel processor 12 is supplied to the fuel cell 11 by the switching valve 14, and generates electric power together with the supplied air. From the fuel cell 11, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged exhaust fuel gas flows through the check valve 15 and is then supplied to the burner 16 and is burned together with the combustion gas or only with the exhaust fuel gas.
[0099]
At this time, the fuel gas pushes the valve element 18 with a pressure larger than the pressure due to the weight of the valve element 18 and the valve element 18 slides by the guide 21, so that the fuel gas flow path is secured.
[0100]
On the other hand, the drain water condensed upstream of the check valve 15 is separated before the check valve 15 and stored in the first drain tank 22.
[0101]
Drain water condensed in the fuel gas flow path before the burner 16 is separated before the burner 16 and stored in the second drain tank 25.
[0102]
The second drain tank 25 has a water level sensor 28 for detecting the water level of the second drain tank 25. When the water level rises and exceeds a first certain threshold value X3, the solenoid valve 27 'is opened by control. Drain water or flows through a water treatment unit (not shown) and then supplies it to a humidifier (not shown) inside the system or a reformer (not shown) of the fuel processor 12. When the water level falls and falls below a second certain threshold value X4, the solenoid valve 27 'is closed to stop drainage of the drain water from the second drain tank 25.
[0103]
In the present embodiment, the drain water stored in the first drain tank 22 and the second drain tank 25 is stored in a balanced manner by the pressure difference and the head difference of each gas present in both tanks. Further, since the second threshold value X4 in the water level sensor 28 is set to be sufficiently large, the gas present in the first drain tank 22 does not flow into the second drain tank 25 through the communication passage 26.
[0104]
Therefore, when the configuration of the polymer electrolyte fuel cell system according to the present embodiment is adopted, the operation described in the fourth embodiment described above can be realized with fewer components.
[0105]
Further, with the configuration according to the present embodiment, it is possible to prevent the fuel gas passage from being blocked when the check valve 15 is stuck due to some trouble.
[0106]
More specifically, in the configuration of the conventional polymer electrolyte fuel cell system (see FIG. 10), when the on-off valve 10 is fixed, the fuel gas flow path is closed and the pressure of the fuel cell 1 and the fuel processor 2 is reduced. Will rise. In the configuration of the polymer electrolyte fuel cell system of the present embodiment (see FIG. 7), if the pressure loss across the check valve 15 exceeds the pressure difference corresponding to the head difference determined by the first threshold value X3, Fuel gas flows from the first drain tank 22 through the communication passage 26, flows into the second drain tank 25, and is guided to the burner 16. Thus, the first drain tank 22, the second drain tank 25, the communication passage 26, and the water level sensor 28 also have a pressure relief function when the pressure of the fuel gas flow path increases.
[0107]
That is, with the configuration of the polymer electrolyte fuel cell system according to the present embodiment, in addition to the operation described in the above-described fourth embodiment, the management of the drain water condensed in the fuel gas flow path can be easily performed with fewer components. A polymer electrolyte fuel cell system that can be realized in a short time.
[0108]
Further, it is possible to realize a polymer electrolyte fuel cell which enables a pressure relief function when the pressure of the fuel gas flow path rises.
[0109]
Thus, the connection between the first drain tank and the second drain tank is set at a position where a water pressure greater than the pressure difference between the gases present in the first drain tank and the second drain tank is applied. A polymer electrolyte fuel cell system that can easily manage drain water condensed in the fuel gas flow path with fewer components can be realized, and a pressure relief function can be provided when the pressure in the fuel gas flow path increases Polymer electrolyte fuel cell that can be realized.
[0110]
Note that the solenoid valve 27 'corresponds to the third drain valve of the present invention.
[0111]
(Embodiment 6)
First, the configuration of the polymer electrolyte fuel cell system according to the present embodiment will be described mainly with reference to FIG. FIG. 8 is a configuration diagram illustrating a polymer electrolyte fuel cell system according to Embodiment 6 of the present invention.
[0112]
The configuration of the polymer electrolyte fuel cell system of the present embodiment is similar to the configuration of the polymer electrolyte fuel cell system of Embodiment 2 described above.
[0113]
However, the polymer electrolyte fuel cell system according to the present embodiment includes a first drain tank 22 for storing water condensed in a fuel gas flow path upstream of the check valve 15, and a water level sensor 24 for detecting a water level. A condenser 29 for condensing water vapor contained in the exhaust fuel gas downstream of the check valve 15, a condensed water tank 30 for storing condensed water condensed in the condenser 29, a first drain tank 22, and a condensed water. A communication passage 31 communicating with the tank 30; an electromagnetic valve 23 for opening and closing the communication passage 31; an electromagnetic valve 32 for discharging mixed water of condensed water and drain water; and a water level for detecting the water level inside the condensed water tank 30 And a sensor 33.
[0114]
After all, the polymer electrolyte fuel cell system according to the present embodiment has a configuration further including a condenser 29 in addition to the components of the polymer electrolyte fuel cell system according to Embodiment 4 described above. ing.
[0115]
Next, the operation of the polymer electrolyte fuel cell system according to the present embodiment will be described.
[0116]
In the fuel processor 12, in order to promote a reforming reaction for generating a hydrogen-rich fuel gas from a raw material gas such as a natural gas, the fuel is heated by a burner 16 at a temperature of about 700 ° C. At the same time, the fuel processor 12 has a function of removing carbon monoxide contained in the fuel gas to a concentration that does not damage the catalyst of the fuel cell 11.
[0117]
When the fuel gas contains a large amount of carbon monoxide at the time of starting the system, the switching valve 14 closes the fuel cell 11 and opens the bypass 13. At this time, the fuel gas discharged from the fuel processor 12 is guided to the bypass 13 by the switching valve 14 and bypasses the fuel cell 11. The fuel gas flowing through the bypass 13 flows through the check valve 15 only in the direction of the burner 16. The fuel gas supplied to the burner 16 is burned together with the combustion gas or only with the fuel gas.
[0118]
At this time, the check valve 15 has the valve body 18 pressed against the valve seat 17 by the self-weight of the valve body 18 and the back pressure from the downstream of the check valve 15, and the fuel gas flow path is closed by the seal member 19. Therefore, backflow of the fuel gas to the fuel cell 11 is prevented.
[0119]
Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the switching valve 14 opens the fuel cell 11 and closes the bypass 13. The fuel gas discharged from the fuel processor 12 is supplied to the fuel cell 11 by the switching valve 14, and generates electric power together with the supplied air. From the fuel cell 11, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged exhaust fuel gas flows through the check valve 15 and is then supplied to the burner 16 and is burned together with the combustion gas or only with the exhaust fuel gas. In this case, the fuel gas pushes the valve element 18 with a pressure greater than the pressure due to the weight of the valve element 18 and the valve element 18 slides by the guide 21, so that the fuel gas flow path is secured.
[0120]
On the other hand, the drain water condensed upstream of the check valve 15 is separated before the check valve 15 and stored in the first drain tank 22.
[0121]
Further, a condenser 29 is provided downstream of the check valve 15, and the exhaust fuel gas is cooled in the condenser 29, and the contained water vapor is condensed into condensed water. The condensed water is separated before the burner 16 and stored in the condensed water tank 30.
[0122]
The first drain tank 22 has a water level sensor 24 for detecting the water level in the first drain tank 22. When the water level rises and exceeds a first certain threshold value X1, the solenoid valve 23 is opened by control. The drain water is discharged to the condensed water tank 30 via the communication passage 31. When the water level falls and falls below a second certain threshold value X2, the solenoid valve 23 is closed to stop the drain water discharge.
[0123]
The condensed water tank 30 has a water level sensor 33 for detecting the water level of the condensed water tank 30. When the water level rises and exceeds a first certain threshold value X3, the condensed water is opened by controlling the solenoid valve 32. The mixed water and drain water are discharged or passed through a water treatment unit (not shown) and then supplied to a humidifier (not shown) in the system or a reformer (not shown) of the fuel processor 12. .
[0124]
Therefore, in the configuration of the polymer electrolyte fuel cell system according to the present embodiment, the drain water condensed upstream of the check valve 15 is separated from the fuel gas upstream of the check valve 15, so that the check valve Only the fuel gas flows through 15. As a result, unstable supply (for example, pulsation) of the fuel gas due to the condensed water remaining in the fuel gas flow path can be prevented, and the operation of the check valve 15 can be performed more stably. It becomes.
[0125]
Further, only by opening and closing the solenoid valve 32, the mixed water of the drain water and the condensed water collected in the condensed water tank 30 is effectively discharged, or the humidification inside the system is performed after flowing to a water treatment device (not shown). The fuel can be supplied to a reformer (not shown) or a reformer (not shown) of the fuel processor 12. Thereby, the drain water condensed in the fuel gas flow path can be centrally managed.
[0126]
Further, using the condenser 29 downstream of the check valve 15, the exhaust fuel gas is cooled, the contained water vapor is condensed, the condensed water condensed is separated before the burner 16, and the condensed water tank 30. Can be stored.
[0127]
That is, with the configuration of the polymer electrolyte fuel cell system according to the present embodiment, in addition to the operation described in the above-described second embodiment, the solid-state fuel cell system that makes it possible to easily manage drain water condensed in the fuel gas flow path A polymer fuel cell system can be realized.
[0128]
Thus, a drain tank for storing water condensed in the fuel gas flow path upstream of the check valve, a condenser for condensing water vapor contained in the exhaust fuel gas, and a condensed water tank for storing condensed water are provided. By connecting the drain tank and the condenser, it is possible to realize a polymer electrolyte fuel cell system capable of easily managing drain water condensed in the fuel gas flow path.
[0129]
The condensed water tank 30 corresponds to the second tank of the present invention, the solenoid valve 32 corresponds to the second drain valve of the present invention, and the water level sensor 33 corresponds to the second tank water level detecting means of the present invention.
[0130]
(Embodiment 7)
First, the configuration of the polymer electrolyte fuel cell system of the present embodiment will be described mainly with reference to FIG. FIG. 9 is a configuration diagram illustrating a polymer electrolyte fuel cell system according to Embodiment 7 of the present invention.
[0131]
The configuration of the polymer electrolyte fuel cell system according to the present embodiment is similar to the configuration of the polymer electrolyte fuel cell system according to Embodiment 6 described above.
[0132]
However, the polymer electrolyte fuel cell system of the present embodiment does not include the solenoid valve 23 (see FIG. 8) and the water level sensor 24 (see FIG. 8). Instead, the second threshold value X4 in the water level sensor 33 indicates that the water pressure that is larger than the pressure difference between the gases present in the first drain tank 22 and the condensed water tank 30 is greater than the connection pressure between the communication passage 31 and the condensed water tank 30. Is set to be large enough.
[0133]
Next, the operation of the polymer electrolyte fuel cell system according to the present embodiment will be described.
[0134]
In the fuel processor 12, in order to promote a reforming reaction for generating a hydrogen-rich fuel gas from a raw material gas such as a natural gas, the fuel is heated by a burner 16 at a temperature of about 700 ° C. At the same time, the fuel processor 12 has a function of removing carbon monoxide contained in the fuel gas to a concentration that does not damage the catalyst of the fuel cell 11.
[0135]
When the fuel gas contains a large amount of carbon monoxide at the time of starting the system, the switching valve 14 closes the fuel cell 11 and opens the bypass 13. At this time, the fuel gas discharged from the fuel processor 12 is guided to the bypass 13 by the switching valve 14 and bypasses the fuel cell 11. The fuel gas flowing through the bypass 13 flows through the check valve 15 only in the direction of the burner 16. The fuel gas supplied to the burner 16 is burned together with the combustion gas or only with the fuel gas.
[0136]
At this time, the check valve 15 has the valve body 18 pressed against the valve seat 17 by the self-weight of the valve body 18 and the back pressure from the downstream of the check valve 15, and the fuel gas flow path is closed by the seal member 19. Therefore, backflow of the fuel gas to the fuel cell 11 is prevented.
[0137]
Conversely, when the concentration of monoxide in the fuel gas is sufficiently low, the switching valve 14 opens the fuel cell 11 and closes the bypass 13. The fuel gas discharged from the fuel processor 12 is supplied to the fuel cell 11 by the switching valve 14, and generates electric power together with the supplied air. From the fuel cell 11, a mixed gas of hydrogen, water vapor, carbon dioxide, and carbon monoxide that has not been used for power generation is discharged. The discharged exhaust fuel gas flows through the check valve 15 and is then supplied to the burner 16 and is burned together with the combustion gas or only with the exhaust fuel gas.
[0138]
At this time, the fuel gas pushes the valve element 18 with a pressure larger than the pressure due to the weight of the valve element 18 and the valve element 18 slides by the guide 21, so that the fuel gas flow path is secured.
[0139]
On the other hand, the drain water condensed upstream of the check valve 15 is separated before the check valve 15 and stored in the first drain tank 22.
[0140]
Further, a condenser 29 is provided downstream of the check valve 15, and the exhaust fuel gas is cooled in the condenser 29, and the contained water vapor is condensed into condensed water. The condensed water is separated before the burner 16 and stored in the condensed water tank 30.
[0141]
The condensed water tank 30 has a water level sensor 33 for detecting the water level of the condensed water tank 30. When the water level rises and exceeds a first threshold X3, the solenoid valve 32 'is opened by control to drain water. The mixed water with the condensed water is discharged or passed through a water treatment device (not shown) and then supplied to a humidifier (not shown) in the system or a reformer (not shown) of the fuel processor 12. . When the water level falls and falls below a second certain threshold value X4, the solenoid valve 32 'is closed to stop the discharge of the mixed water of the drain water and the condensed water from the condensed water tank 30.
[0142]
In the present embodiment, the mixed water of the drain water and the condensed water stored in the first drain tank 22 and the condensed water tank 30 is balanced by the pressure difference and the head difference of each gas present in both tanks. Water is stored. Further, since the second threshold value X4 in the water level sensor 33 is set to be sufficiently large, the gas present in the first drain tank 22 does not flow into the condensed water tank 30 through the communication passage 31.
[0143]
Therefore, when the configuration of the polymer electrolyte fuel cell system according to the present embodiment is adopted, the operation described in the sixth embodiment described above can be realized with fewer components.
[0144]
Further, with the configuration according to the present embodiment, it is possible to prevent the fuel gas passage from being blocked when the check valve 15 is stuck due to some trouble.
[0145]
More specifically, in the configuration of the conventional polymer electrolyte fuel cell system (see FIG. 10), when the on-off valve 10 is fixed, the fuel gas flow path is closed and the pressure of the fuel cell 1 and the fuel processor 2 is reduced. Will rise. In the configuration of the polymer electrolyte fuel cell system of the present embodiment (see FIG. 8), if the pressure loss across the check valve 15 exceeds the pressure difference corresponding to the head difference determined by the first threshold value X3, Fuel gas flows from the first drain tank 22 to the condensed water tank 30 through the communication passage 31, and is guided to the burner 16. Thus, the first drain tank 22, the condensed water tank 30, the communication path 31, and the water level sensor 33 also have a pressure relief function when the pressure of the fuel gas flow path increases.
[0146]
That is, with the configuration of the polymer electrolyte fuel cell system according to the present embodiment, in addition to the operation described in the above-described sixth embodiment, the management of the drain water condensed in the fuel gas flow path can be easily performed with fewer components. A polymer electrolyte fuel cell system that can be realized in a simple manner can be realized.
[0147]
Further, it is possible to realize a polymer electrolyte fuel cell which enables a pressure relief function when the pressure of the fuel gas flow path rises.
[0148]
Thus, by setting the connection portion of the condensed water tank with the drain tank to a position where a water pressure that is larger than the pressure difference of each gas present in the drain tank and the condensed water tank is applied, the drain water condensed in the fuel gas passage is A polymer electrolyte fuel cell system that enables easy management with fewer components can be realized, and a polymer electrolyte fuel cell that enables a pressure relief function when the pressure in the fuel gas flow path increases can be realized. .
[0149]
Note that the solenoid valve 32 'corresponds to the third drain valve of the present invention.
[0150]
In the above, Embodiments 1 to 7 have been described in detail.
[0151]
Since a large amount of water vapor contained in the exhaust fuel gas may condense at the check valve 15, the valve seat 17, the valve body 18, the sealing member 19, the spring 20, the guide 21 Is made of a water-repellent material or a material coated with a water-repellent agent, which is useful because it prevents the check valve 15 from sticking. When collecting and reusing drain water and condensed water inside the polymer electrolyte fuel cell system, metal ions and organic substances contained in the water are problematic, but the water-repellent material and water-repellent are fluorine-based materials. This can solve such a problem, and is useful for stable operation of the water recovery unit of the polymer electrolyte fuel cell system.
[0152]
Further, in the present embodiment described above, the first tank of the present invention and the second tank of the present invention are connected, but the present invention is not limited to this, and the first tank and the second tank may not be connected (the first tank and the second tank). If the second tank is not in communication, the water stored in the first tank is drained only based on the detection result by the first tank water level detecting means of the present invention, and stored in the second tank. The draining of the water is performed based only on the detection result by the second tank water level detecting means of the present invention).
[0153]
Further, a fuel cell flowing step for flowing the fuel gas so that the fuel gas flows from the fuel gas inlet and flows out of the fuel gas outlet, so that the fuel gas can flow by bypassing the fuel cell. A bypass step of bypassing between the fuel gas inlet and the fuel gas outlet; a switching step of switching whether the fuel gas flows through the fuel cell or the bypass; and the fuel gas bypasses the fuel cell. A backflow preventing step of preventing the fuel gas from flowing back to the fuel cell side by utilizing a check valve provided on the fuel gas outlet side when the switching is performed as described above. The fuel cell control method is included in the invention related to the present invention.
[0154]
【The invention's effect】
As is apparent from the above description, the present invention has an advantage that safe operation of, for example, a polymer electrolyte fuel cell can be realized with lower power consumption, lower cost, and smaller size.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 1.
FIG. 2 is a configuration diagram of a check valve according to the first embodiment.
FIG. 3 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 2.
FIG. 4 is a configuration diagram of a check valve according to a second embodiment.
FIG. 5 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 3.
FIG. 6 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 4.
FIG. 7 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 5.
FIG. 8 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 6.
FIG. 9 is a configuration diagram showing a polymer electrolyte fuel cell system according to Embodiment 7.
FIG. 10 is a configuration diagram showing a conventional polymer electrolyte fuel cell system.
[Explanation of symbols]
1,11 fuel cell
2,12 fuel processor
3 Humidifier
4,29 Condenser
5, 30 Condensate tank
6, 16 burners
7. Combustion fan
8, 13 Bypass road
9,14 switching valve
10 On-off valve
15, 15 'check valve
17 Valve seat
18 Valve
19 Sealing material
20 spring
21 Guide
22, 25 Drain tank
23, 27, 27 ', 32, 32' Solenoid valve
24, 28, 33 Water level sensor
26, 31 communication passage

Claims (13)

A fuel cell that flows so that fuel gas flows in from a fuel gas inlet and flows out of a fuel gas outlet;
A bypass passage for bypassing between the fuel gas inlet and the fuel gas outlet, so that the fuel gas can flow by bypassing the fuel cell;
Switching means for switching whether the fuel gas flows through the fuel cell or the bypass path,
A check valve provided on the fuel gas outlet side for preventing the fuel gas from flowing back to the fuel cell side when the switching is performed so that the fuel gas flows through the bypass passage. A fuel cell system comprising: The check valve includes a valve body for preventing the fuel gas from flowing back to the fuel cell side, and the valve when the switching is performed such that the fuel gas flows through the bypass passage. The fuel cell system according to claim 1, further comprising a valve seat against which a body is pressed. 3. The fuel cell system according to claim 2, wherein the pressing of the valve body is performed using a predetermined elastic body. The valve body is mounted on the valve seat on the basis of a vertical direction,
The fuel cell system according to claim 2, wherein the pressing of the valve element is performed by using the weight of the valve element. 2. The fuel cell system according to claim 1, further comprising a first tank provided between the fuel gas outlet and the check valve for storing condensed water. First tank water level detection means for detecting the water level of the first tank,
6. A drain valve provided in the first tank for draining water stored in the first tank based on a detection result by the first tank water level detecting means. A fuel cell system as described. A burner to which fuel gas that has flowed through the fuel cell or fuel gas that has flowed through the bypass path is supplied;
7. The fuel cell system according to claim 5, further comprising a second tank provided between the end point of the bypass passage and the burner for storing condensed water. Second tank water level detection means for detecting the water level of the second tank,
A second drain valve provided in the second tank for draining at least the water stored in the second tank, based on the result of the detection by at least the second tank water level detecting means. The fuel cell system according to claim 7, further comprising: A communication passage communicating the first tank and the second tank,
First tank water level detection means for detecting the water level of the first tank,
A first drain valve provided in the communication path for draining water stored in the first tank based on a detection result by the first tank water level detecting means. 9. The fuel cell system according to 7 or 8. A communication passage communicating the first tank and the second tank such that the water level of the second tank is higher than the water level of the first tank;
Second tank water level detection means for detecting the water level of the second tank,
The drainage of water stored in the first tank and the drainage of water stored in the second tank are performed based on the detection result by the second tank water level detection means, The fuel cell system according to claim 7, further comprising a third drain valve provided in the tank. The fuel cell system according to claim 7, further comprising a condenser provided between the end point of the bypass and the second tank for condensing the water. The fuel cell system according to claim 1, wherein the check valve is configured using a water-repellent material. The fuel cell system according to claim 12, wherein the water-repellent material is a fluorine-based material.

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