JP2002170588A - Deionized water recovery system for fuel battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reclaiming ratio of the steam contained in a gas discharged from a fuel battery stack 12. SOLUTION: A needle valve 31 is provided on the downstream side of a condenser 20 for reclaiming the steam in the gas, so that the pressure in the condenser 20 rises. The deionized water is injected form an injection valve 34 into the gas flowing into the condenser 20, so that the gas temperature is lowered and the gas humidity get high. The above steps allow the steam to be easily condensed in the condenser 20, thus the above purpose is achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell pure water recovery apparatus for condensing and recovering water vapor generated from an air electrode or a hydrogen electrode of a fuel cell mounted on an electric vehicle or the like. This is to lengthen the cycle of replenishing water into the tank storing water for improving power generation efficiency.

[0002]

2. Description of the Related Art The principle of power generation by a fuel cell will be briefly described with reference to FIG. FIG. 8 shows only one cell 1 as a unit of the fuel cell. The middle part of this cell 1
An electrolyte 2 such as phosphoric acid is partitioned by a thin film 5 sandwiched between a hydrogen electrode 3 and an air electrode (oxygen electrode) 4 in a sandwich manner. The thin film 5 has a property of transmitting only hydrogen ions (H ⁺ ). Further, hydrogen gas (H ₂ ) is fed into the first reaction chamber 6 on the side of the hydrogen electrode 3 from a hydrogen supply port 7, and a gas containing unreacted hydrogen gas can be discharged from a hydrogen reflux port 8. Further, air containing oxygen (O ₂ ) is fed into the second reaction chamber 9 on the side of the air electrode 4 from the oxygen supply port 10 and can be freely discharged from the exhaust port 11.

When power is generated, hydrogen gas is supplied from the hydrogen supply port 7 into the first reaction chamber 6 and the oxygen supply port 1 is supplied to the first reaction chamber 6.
From 0, air containing oxygen is supplied into the second reaction chamber 9, respectively. As a result, a reaction of H ₂ → 2H ⁺ + 2e ⁻ occurs in the portion of the hydrogen electrode 3 facing the first reaction chamber 6, and the resulting hydrogen ions pass through the thin film 5 and the second reaction occurs. Enter the room 9. Then, in the air electrode 4 portion facing to the second reaction chamber _{^{9, 2H + + O 2/}} 2 + 2e - → H 2 O reaction occurs. As a result, a potential difference occurs between the hydrogen electrode 3 and the air electrode 4. Since the potential difference generated for each cell 1 is only about 1 V, as shown in FIG.
Are stacked in series to form a fuel cell stack 12 (see FIG. 9 described below) to secure a required voltage. Since the current obtained by the fuel cell stack 12 is a direct current, if an alternating current is required, the current is converted by the inverter 13 (see FIG. 9).

In order to activate the reaction in the hydrogen electrode 3 and the air electrode 4 when power is generated in the cell 1 based on the above-described principle, the hydrogen supply port 7 is required to secure the power generation efficiency.
Therefore, it is necessary to wet (humidify) the hydrogen gas fed into the first reaction chamber 6 and the air containing oxygen sent from the oxygen supply port 10 into the second reaction chamber 9. For this reason, conventionally, the fuel cell has been configured with a circuit as shown in FIG. 9 to humidify the hydrogen gas and the air. A large number of sensors are incorporated in the circuit shown in FIG. 9, and a controller (not shown) controls each component in accordance with the detection signals of these sensors. However, regarding the configuration and operation of this part, various types are conventionally known,
Since there are many things that are not related to the gist of the present invention, only the installation position of the sensor is shown in the drawing, and the detailed description is omitted. still,
In FIG. 9, a sensor in which a symbol “T” is circled is a temperature sensor, a sensor in which a symbol “P” is circled is a pressure sensor, and a sensor in which symbol “H” is circled. Indicates a dew point sensor.

First, a circuit for feeding and discharging hydrogen gas into the first reaction chamber 6 (see FIG. 8) of each cell 1 constituting the fuel cell stack 12 will be described. Hydrogen supplied from a tank of a hydrogen storage alloy or the like or from a fuel reformer is jetted from a nozzle of an ejector 14, humidified by a hydrogen humidifier 15, and then sent into the fuel cell stack 12. . Each of the cells 1 is passed through a hydrogen distribution passage provided in the fuel cell stack 12.
From the hydrogen supply port 7 (see FIG. 8). Excess hydrogen gas not consumed in the first reaction chamber 6 is discharged from the hydrogen reflux port 8 (see FIG. 8) of each of the cells 1, and is returned to the suction port of the ejector 14 through the reflux path 16. Sent. The surplus hydrogen gas sucked into the ejector 14 in this manner, together with the hydrogen gas supplied from the tank or the reformer,
It is sent into the first reaction chamber 6 again. In addition, a gate valve 17 is provided in the middle of the reflux passage 16 so that, when a large amount of hydrogen gas is consumed in the first reaction chamber 6, the hydrogen gas in the first reaction chamber 6 is discharged from the ejector 6. 14 so as not to be sucked.

Next, a circuit for sending and discharging air into the second reaction chamber 9 (see FIG. 8) of each cell 1 constituting the fuel cell stack 12 will be described. The air taken in through an air filter (not shown) and discharged from the compressor 18 is humidified by an air humidifier 19,
The fuel is sent into the fuel cell stack 12. And
The oxygen is supplied from the oxygen supply port 10 (see FIG. 8) of each of the cells 1 into the second reaction chamber 9 through an air distribution channel provided in the fuel cell stack 12. Air containing excess oxygen that has not been consumed in the second reaction chamber 9 is discharged from the exhaust port 11 (see FIG. 8) of each of the cells 1 and passes through the condenser 20, and then enters the atmosphere. Is discharged.

The condenser 20 is connected to the exhaust port 1.
It condenses the water vapor contained in the air discharged from 1 and collects it as pure water. For example, it is configured as shown in FIG. The condenser 20 has cooling passages 21 and 21 for flowing air containing water vapor in an upstream portion thereof and pure water and air generated by condensation of the water vapor in a downstream portion thereof. Each of these cooling channels 21,
A gas receiving port 22 is provided at the upstream end of the fuel cell stack 21 so that the gas sent from the air electrode side exhaust port 11 of each cell 1 constituting the fuel cell stack 12 can be freely received. Further, a discharge port 23 is provided at the downstream end of each of the cooling channels 21, 21, and the discharge port 23 communicates with a gas-liquid separator (not shown). Then, the condensed water discharge port of the gas-liquid separator is connected to a water storage tank 24 storing pure water to be supplied to the hydrogen humidifier 15 and the air humidifier 19. Further, the gas discharged from the exhaust port of the gas-liquid separator can be freely discharged into the atmosphere.

On the other hand, the condenser 20 has refrigerant passages 25, 25 adjacent to the cooling passages 21, 21, respectively.
Are provided, and a coolant such as cooling water (coolant) can flow freely in each of the coolant channels 25. For this,
A refrigerant inlet 26 is provided at an upstream end of each of the refrigerant channels 25, 25.
, And a refrigerant outlet 27 at the downstream end.
Then, the refrigerant outlet 27 is connected to an inlet of a radiator 28 for radiating the cooling water, and the refrigerant inlet 26 is connected to a discharge port of a water supply pump 29 for taking out the cooling water from the radiator 28 and discharging the same. ing. When an apparatus equipped with a fuel cell, such as an electric vehicle, is operated, the operation of the water supply pump 29 is accompanied by the operation of the refrigerant flow paths 25, 2, and 2.
Cooling water is circulated in the cooling water passage 5, and condenses and liquefies the water vapor contained in the air flowing in each of the cooling channels 21.
In the illustrated example, the heat is radiated by the radiator 28 and the cooling water discharged from the water pump 29 causes
Cooling of devices that generate heat during operation of the electric vehicle, such as the fuel cell stack 12, the inverter 13, and the electric motor, is also performed.

With the above-described configuration, the second reaction chamber 9
Since the water vapor contained in the air discharged from the fuel cell is condensed and collected in the water storage tank 24, the consumption of pure water required for efficient power generation of the fuel cell can be reduced. That is, it is sent out from the water storage tank 24 and sent to the hydrogen humidifier 15 and the air humidifier 19 by the second water pump 30.
Further, the pure water fed into the first reaction chamber 6 and the second reaction chamber 9 only plays a role of efficiently performing the reaction in each of the reaction chambers 6, 9. ,
It is not consumed within 9. The gas discharged from the second reaction chamber 9 includes the air humidifier 1.
9 in addition to the water vapor supplied into the air,
Resulting in _{^{partial, 2H + + O 2/2}} + 2e - → contains steam generated by H ₂ O becomes reactions. Therefore, conventionally, by providing the condenser 20, the water vapor contained in the air discharged from the second reaction chamber 9 is condensed and collected in the water storage tank 24, so that the efficient power generation of the fuel cell is achieved. It is considered to reduce the consumption of pure water necessary for this purpose.

[0010]

In the case of the conventional pure water recovery apparatus for a fuel cell which is constructed and operates as described above, the gas flowing through the cooling passages 21 and 21 in the condenser 20 portion is contained in the gas. Condensation of the contained water vapor is not always performed efficiently. The main reasons why the condensation is inefficient and the recovery of pure water is low are as follows.

For example, in summer, the temperature of the cooling water flowing through the refrigerant passages 25 of the condenser 20 ranges from 60 to 7 depending on the outside air temperature that changes depending on the season and the like.
It reaches about 0 ° C. On the other hand, in the case of the conventional structure, the downstream ends of the cooling passages 21 and 21 of the condenser 20 are open to the atmosphere, so that the pressure in the cooling passages 21 and 21 is almost atmospheric pressure. Was. Then, the saturation temperature under atmospheric pressure, which is the temperature at which the gas discharged from the second reaction chamber 9 and flowing through each of the cooling channels 21, 21 starts to condense under atmospheric pressure, is about 80 ° C. . Therefore, the difference between the saturation temperature and the temperature of the cooling water is small,
The condensation of the water vapor contained in the gas flowing through the insides 1, 21 is not efficiently performed, and the recovery rate of the pure water is reduced.

Although it depends on the outside air temperature which changes with the season and the like, for example, in the summer,
The water vapor contained in the air flowing through each of the 0 cooling channels 21 is in an overheated state. The heat transfer between the superheated steam and another fluid is a so-called gas heat transfer state, so that the heat transfer coefficient is low, and it is difficult to cool the superheated steam. Moreover, in order to condense the superheated steam, it is necessary to lower the temperature of the air to the saturation temperature of the steam and then further lower it. Therefore, the condensation of the water vapor contained in the gas flowing through the cooling channels 21 is not efficiently performed, and the recovery rate of the pure water is reduced.

In order to prevent a reduction in the recovery rate of pure water caused by the above-mentioned causes, it is conceivable to increase the size of the condenser 20. This is not preferable because it causes an increase in the size and weight of the device. The pure water recovery device for a fuel cell according to the present invention has been made in view of the above-described circumstances, and has been invented to improve the pure water recovery rate without increasing the size of the condenser 20.

[0014]

Each of the pure water recovering apparatuses for a fuel cell according to the present invention is provided with a condenser, similarly to the conventionally known pure water recovering apparatus for a fuel cell. In order to condense and recover water vapor contained in the gas discharged from the fuel cell stack, the condenser is provided at a cooling flow path through which the gas and the condensed water flow, and at an upstream end of the cooling flow path. A gas receiving port for receiving gas sent out from an exhaust port of the air electrode of the fuel cell stack, and a condensed water discharge port for returning condensed water generated by condensation of the water vapor in the cooling flow path to a water storage tank. A second exhaust port for discharging the gas excluding the condensed water, and a refrigerant flow path for flowing a refrigerant for cooling the gas flowing in the cooling flow path.

In particular, in the pure water recovery apparatus for a fuel cell according to the first aspect, the cooling water flow path is provided with a resistance to the flow of gas flowing through the cooling flow path downstream of the cooling flow path. A resistance portion for increasing the pressure in the flow path is provided. In the pure water recovery device for a fuel cell according to the third aspect, the cooling flow may flow through the gas supply passage in the middle of the gas supply passage between the exhaust port and the gas receiving port. An injection valve for injecting water into the gas sent to the road is provided.

[0016]

According to the pure water recovery apparatus for a fuel cell of the present invention constructed as described above, the pure water recovery rate can be improved without increasing the size of the condenser. First, in the case of the pure water recovery device for a fuel cell according to the first aspect, the saturation temperature of the gas flowing in the cooling flow channel increases as the pressure in the cooling flow channel increases. For this reason, the difference between the saturation temperature and the temperature of the refrigerant flowing in the refrigerant channel can be increased, and accordingly, the water vapor contained in the gas is easily condensed.
Further, in the case of the fuel cell pure water recovery device according to the third aspect, the temperature of the gas flowing through the cooling flow path decreases, and the water vapor in the gas becomes saturated steam or wet steam. Therefore, the heat transfer between the refrigerant flowing through the refrigerant flow path and the water vapor is condensed heat transfer having a high transfer coefficient, and the temperature of the water vapor can be efficiently reduced. Further, since the temperature decrease of the steam directly leads to the condensation of the steam, the condensation and liquefaction of the steam can be performed efficiently.

[0017]

1 and 2 show a first embodiment of the present invention corresponding to claims 1, 2 and 8. FIG.
The feature of the present embodiment is that the pressure in the cooling passages 21 and 21 (see FIG. 10) constituting the condenser 20 is increased in order to improve the recovery rate of the pure water at the condenser 20 portion. Since the structure and operation of the other parts are the same as those of the above-described conventional structure, the description of the equivalent parts will be omitted or simplified, and the following description will focus on the characteristic parts of the present invention.

The resistance to the flow of gas discharged from the discharge port 23 is provided downstream of the discharge port 23 (see FIG. 10) provided at the downstream end of each of the cooling passages 21 constituting the condenser 20. Is provided. This throttle valve 31 is capable of adjusting the flow path area in response to a command from a controller (not shown). When the flow passage area is reduced, the back pressure of each of the cooling flow passages 21 is increased to increase the pressure in each of the cooling flow passages 21. On the other hand, when the flow area is increased,
By lowering the back pressure of each of the cooling channels 21, 21, the pressure in each of the cooling channels 21, 21 is reduced (close to the atmospheric pressure).

A signal from a water level sensor 32 for detecting the water level in the water storage tank 24 is input to the controller.
The controller operates the throttle valve 31 when the water level in the water storage tank 24 detected by the water level sensor 32 is low.
And the pressure in each of the cooling channels 21 is increased.

According to the pure water recovery apparatus for a fuel cell of this embodiment constructed as described above, the pressure in each of the cooling passages 21 is increased by the amount of increase in the pressure in each of the cooling passages 21. The temperature of the saturated gas increases. For this reason, the difference between the saturation temperature and the temperature of the cooling water flowing through each of the coolant flow paths 25, 25 (see FIG. 10) can be increased. Water vapor contained in the generated gas is easily condensed.

FIG. 2 shows the results of an experiment conducted to confirm the effect of this embodiment. In FIG. 2, the horizontal axis represents the flow rate of the gas containing water vapor flowing through each of the cooling channels 21, 21, and the vertical axis represents the water vapor generated by condensation and liquefaction of the water vapor within each of the cooling channels 21, 21. The amount of pure water used is shown. In addition, as the gas containing the water vapor, the temperature at the upstream end portion of each of the cooling passages 21 is 90 ° C.
And air containing 20% by weight of water vapor was used. In FIG. 2 showing the results of the experiment performed under such conditions, the solid line a indicates that the pressure in each of the cooling passages 21 is 1.1 atm (absolute pressure).
, And the dashed line b indicates the case of 1.4 atm. Although this pressure was measured at the inlet of the condenser 20, it is considered that the pressure is almost the same at the outlet.

As is apparent from FIG. 2, by increasing the pressure in each of the cooling passages 21, the amount of condensation and liquefaction of steam in the condenser 20 is increased, and The amount of collection can be increased. The above capacitor 2
In the case where only the recovery amount of pure water in the zero part is considered, the flow path of the throttle valve 31 is kept narrow, and the pressure in the cooling flow paths 21 and 21 is kept high. Just do it. However, in such a case, the power for driving the compressor 18 for sending air into the second reaction chamber 9 (see FIG. 8) of each cell 1 constituting the fuel cell stack 12 always increases. Accordingly, of the electric power generated in the fuel cell stack 12, the amount of consumption inside the fuel cell increases. In addition, the amount of electric power that can be extracted to the outside for running the electric vehicle or the like is reduced. Therefore, in the case of this example, the opening degree of the throttle valve 31 is adjusted in accordance with the amount of water stored in the water storage tank 24, and while suppressing the power consumption,
It is configured such that the amount of water stored in the water storage tank 24 is not insufficient.

Next, FIGS.
5 shows a second example of the embodiment of the present invention corresponding to FIG. The feature of this example is that in order to improve the recovery rate of pure water at the condenser 20, the humidity of the air containing water vapor, which is sent into the cooling passages 21 and 21 (see FIG. 10) constituting the condenser 20, is increased. Is to do. Since the structure and operation of the other parts are the same as the conventional structure described above,
Description of equivalent parts is omitted or simplified.
The following description focuses on features of the present invention.

In the case of this embodiment, the exhaust port 11 of each cell 1 constituting the fuel cell stack 12 (see FIG. 8) and the gas receiving port 22 provided in the condenser 20 (see FIG. 10).
An injection valve 34 is provided in the middle of the gas feed passage 33 between the two. The injection valve 34 allows water to be freely injected into the gas sent to the cooling channels 21 in the gas feed channel 33. That is, the water storage tank 2
Part of the pure water taken out of the pump 4 and pressurized by the second water pump 30 is fed into the injection valve 34, and the gas flowing in the gas feed channel 33 can be humidified.

Further, in the case of the illustrated example, the control valve corresponds to a control valve according to claims 4 and 5 in the middle of a water supply passage 35 for supplying pure water from the water storage tank 24 to the injection valve 34. A flow control valve 36 is provided so that the amount of water sent to the injection valve 34 in the water supply passage 35 can be adjusted. The flow control valve 36 includes the water supply passage 3.
The one that can completely block 5 is used. A water level sensor for detecting the water level in the water storage tank 24 is provided to a controller (not shown) for adjusting the flow path area of the flow rate adjusting valve 36 (including a case where the area is set to zero for blocking). 3
2 and the cooling channels 21 and 2 of the condenser 20.
The temperature sensor and the pressure sensor signal for detecting the temperature and pressure of the gas sent into the apparatus 1 are input.

The controller controls the water level sensor 3
When the water level in the water storage tank 24 detected by 2 is low, the flow control valve 36 is released to allow pure water to be ejected from the injection valve 34 into the gas feed passage 33. In addition, the controller is configured to detect when the water level sensor 32 detects that the amount of water in the water storage tank 24 is small, and that the temperature of the gas detected by the temperature sensor is equal to the temperature of the gas detected by the pressure sensor. When the pressure is equal to or more than the value determined in accordance with the pressure, the flow control valve 36 is released, and water is jetted into the gas feed passage 33. FIG. 4 shows the relationship between the temperature and the pressure at which water is jetted into the gas feed channel 33. The horizontal axis of FIG. 4 represents the pressure of the gas discharged from the exhaust port of the fuel cell stack 12, and the vertical axis similarly represents the temperature. Then, when the temperature of the gas detected by the temperature sensor is above the curve α described in FIG. 4, pure water can be ejected from the injection valve 34 into the gas feed passage 33. .

In the case of the pure water recovery apparatus for a fuel cell according to the present embodiment having the above-described structure, the pure water is ejected from the injection valve 34 into the gas feed passage 33 and the condenser 20 is discharged. The temperature of the gas flowing through each of the cooling passages 21 decreases, and the water vapor in the gas becomes saturated steam or wet steam. For this reason, the heat transfer between the cooling water and the steam flowing in the refrigerant flow paths 25, 25 (see FIG. 10) constituting the condenser 20 becomes a condensation heat transfer with a high transfer coefficient, and the temperature of the steam is efficiently reduced. Can be lowered. Further, since the temperature decrease of the steam directly leads to the condensation of the steam, the condensation and liquefaction of the steam can be performed efficiently.

FIG. 5 shows the results of a first experiment performed to confirm the effect of the present embodiment. In FIG. 5, the horizontal axis represents the flow rate of the gas containing water vapor flowing through each of the cooling channels 21, 21, and the vertical axis represents the water vapor generated by condensation and liquefaction of the steam within each of the cooling channels 21, 21. The amount of pure water used is shown. As the gas containing water vapor, air having a temperature of 90 ° C. at the upstream end of each of the cooling passages 21 and 20 containing 20% by weight of steam and a gas containing 20% by weight of steam having a temperature of 80 ° C. Used with air.

In FIG. 5 showing the results of the first experiment conducted under such conditions, the solid line a indicates the case where the temperature of the gas flowing through the cooling passages 21 is 90 ° C., and the chain line b indicates the case. Similarly, the case where the temperature is 80 ° C. is shown. As is apparent from FIG. 5, if the temperature of the gas flowing through each of the cooling passages 21 is lowered, the amount of condensation and liquefaction of steam at the condenser 20 is increased, and the pure water is recovered. The amount can be increased.

FIG. 6 shows the results of a second experiment conducted to confirm the effect of the present embodiment. This FIG.
The abscissa indicates the flow rate of the gas containing water vapor flowing through the cooling passages 21, 21, and the ordinate indicates the cooling passages 21, 21.
Represents the amount of pure water generated by condensation and liquefaction of water vapor in the inside. As the gas containing water vapor, air having a temperature of 90 ° C. at the upstream end portion of each of the cooling passages 21 and 15 containing 15% by weight of water vapor, and a gas having a temperature of 90 ° C. and containing 15% by weight of water vapor Used with air.

In FIG. 6 showing the results of the second experiment conducted under such conditions, the solid line a indicates the case where the ratio of water vapor in the gas flowing through each of the cooling passages 21 is 15% by weight. , The dashed line b indicates the case where the weight is 20% by weight. As is apparent from FIG. 6, if the proportion of water vapor contained in the gas flowing through each of the cooling passages 21 is increased, the amount of water vapor condensed and liquefied at the condenser 20 can be increased. Moreover, FIG.
As is clear from the above, the rate at which the amount of condensed and liquefied liquid increases is greater than the rate of water vapor contained in the gas. As is evident from this, if an appropriate amount of pure water is injected into each of the cooling passages 21 through the injection valve 34, the amount of condensation and liquefaction is increased more than the injection amount of the pure water. The amount of pure water recovered can be increased. That is, if the pure water is injected through the injection valve 34 in the range shown in FIG. 4 described above, the amount of condensation and liquefaction is increased more than the injection amount, and the reduction of the pure water in the water storage tank 24 is suppressed. Can do things. When the structure of the present embodiment is implemented, not only the flow control valve 36 is controlled to open and close according to the pressure and temperature of the gas discharged from the exhaust port of the fuel cell stack 12, but also the flow path area is reduced. If finely adjusted, the recovery rate of the pure water can be further improved.

Next, FIG. 7 corresponds to claims 6 to 8.
13 shows a third example of the embodiment of the present invention. In the case of this example, a throttle valve 31 is provided to provide each cooling passage 21, 21 (FIG. 1).
0), and the cooling passages 21 and 21 are increased.
By increasing the internal pressure and simultaneously injecting pure water from the injection valve 34 into the gas feed channel 33, the gas flowing through the gas feed channel 33 can be humidified. In the case of the present embodiment, by combining the operation of the first example described above and the operation of the second example described above, the recovery rate of the water vapor contained in the gas discharged from the fuel cell stack 12 is improved. Can be further improved.

[0033]

The pure water recovery apparatus for a fuel cell according to the present invention is constructed and operates as described above. Therefore, the recovery rate of water vapor contained in the gas discharged from the fuel cell stack is improved, Insufficient amount of water can be prevented. Because of this,
During operation of an electric vehicle using a fuel cell as a power source, it is possible to prevent a shortage of pure water at a location where power generation efficiency of the fuel cell is secured, thereby contributing to stable operation of the electric vehicle.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a first example of an embodiment of the present invention.

FIG. 2 is a diagram showing the results of an experiment performed to confirm the effects of the first example.

FIG. 3 is a circuit diagram showing a second example of the embodiment of the present invention.

FIG. 4 is a diagram showing conditions for performing water injection from an injection valve.

FIG. 5 is a diagram showing the results of a first experiment performed to confirm the effect of the second example.

FIG. 6 is a diagram showing the results of the second experiment.

FIG. 7 is a circuit diagram showing a third example of the embodiment of the present invention.

FIG. 8 is used to explain the power generation principle of a fuel cell;
Schematic sectional view of a cell.

FIG. 9 is a circuit diagram showing an example of a structure conventionally considered.

FIG. 10 is a schematic perspective view showing an example of a condenser for collecting pure water.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 cell 2 electrolyte 3 hydrogen electrode 4 air electrode 5 thin film 6 first reaction chamber 7 hydrogen supply port 8 hydrogen reflux port 9 second reaction chamber 10 oxygen supply port 11 exhaust port 12 fuel cell stack 13 inverter 14 ejector 15 hydrogen humidifier 16 Annular flow path 17 Gate valve 18 Compressor 19 Air humidifier 20 Condenser 21 Cooling flow path 22 Gas receiving port 23 Discharge port 24 Water storage tank 25 Refrigerant flow path 26 Refrigerant inlet 27 Refrigerant outlet 28 Radiator 29 Water pump 30 Second water pump 31 Restrictor Valve 32 Water level sensor 33 Gas feed passage 34 Injection valve 35 Water supply passage 36 Flow control valve

Claims (8)

[Claims] A cooling flow path for circulating the gas and condensed water for condensing and recovering water vapor contained in a gas discharged from the fuel cell stack; and a cooling flow path provided at an upstream end of the cooling flow path. A gas receiving port for receiving gas sent out from an exhaust port of the air electrode of the fuel cell stack;
A condensed water discharge port for returning condensed water generated by condensation of the water vapor in the cooling channel to the storage tank, a second exhaust port for discharging gas excluding the condensed water, In a fuel cell pure water recovery device provided with a condenser having a refrigerant flow path for flowing a refrigerant for cooling gas flowing in the cooling flow path, on the downstream side from the cooling flow path, A pure water recovery device for a fuel cell, comprising: a resistance portion for increasing the pressure in the cooling flow path as a resistance to the flow of gas flowing through the cooling flow path. And a controller for adjusting the flow path area of the throttle valve, wherein a signal of a water level sensor for detecting a water level in the water storage tank is provided. 2. The controller according to claim 1, wherein when the water level in the water storage tank detected by the water level sensor is low, the controller reduces the flow path area of the throttle valve to increase the pressure in the cooling flow path. 2. The pure water recovery device for a fuel cell according to 1. 3. A cooling flow path through which the gas and the condensed water flow to condense and recover water vapor contained in the gas discharged from the fuel cell stack, and an upstream end of the cooling flow path, A gas receiving port for receiving gas sent out from an exhaust port of the air electrode of the fuel cell stack;
A condensed water discharge port for returning condensed water generated by condensation of the water vapor in the cooling channel to the water storage tank, a second exhaust port for discharging gas excluding the condensed water, In a fuel cell pure water recovery device provided with a condenser having a refrigerant flow path for flowing a refrigerant for cooling a gas flowing in a cooling flow path, the exhaust port and the gas receiving port A fuel injection valve for injecting water into the gas sent through the gas feed passage toward the cooling flow passage in the middle of the gas feed flow passage between the two. apparatus. 4. A control valve for controlling whether or not water is supplied to the injection valve through the water supply passage is provided in a water supply passage for supplying water to the injection valve. The signal of the water level sensor for detecting the water level in the water storage tank is input to the controller for controlling the opening and closing of the water tank, and this controller is used when the water level in the water storage tank detected by the water level sensor is low. 4. The pure water recovery device for a fuel cell according to claim 3, wherein the control valve is released to eject water into the water supply passage. 5. A control valve for controlling whether water is sent to the injection valve through the water supply passage is provided in a water supply passage for supplying water to the injection valve. The controller for controlling the opening and closing of the is input with the signals of the temperature sensor and the pressure sensor for detecting the temperature and the pressure of the gas discharged from the exhaust port of the fuel cell stack. When the temperature of the gas detected by the temperature sensor is equal to or higher than a value determined according to the pressure of the gas detected by the pressure sensor, the control valve is released,
The pure water recovery device for a fuel cell according to any one of claims 3 to 4, wherein water is jetted into the gas feed passage. 6. A cooling device further comprising a resistance portion provided downstream of the cooling passage to increase the pressure in the cooling passage as a resistance to the flow of gas flowing through the cooling passage.
The pure water recovery device for a fuel cell according to any one of the above. 7. A throttle valve whose resistance section is adjustable in flow path area. A controller for adjusting the flow path area of the throttle valve outputs a signal of a water level sensor for detecting a water level in the water storage tank. 7. The controller according to claim 6, wherein when the water level in the water storage tank detected by the water level sensor is low, the controller reduces the flow path area of the throttle valve to increase the pressure in the cooling flow path. 2. The pure water recovery device for a fuel cell according to 1. 8. A condensed water discharge port and a second exhaust port are provided as a single discharge port at a downstream end of a cooling flow path provided in the condenser body. 8. The pure water recovery device for a fuel cell according to claim 1, wherein the exhaust port is provided at a downstream end of a gas-liquid separator provided downstream of the single discharge port. .