JPH08138708A - Water treatment system of fuel cell power generating facility - Google Patents

Abstract

PURPOSE: To provide a water treatment system of a fuel cell power generating facility with high efficiency by efficiently utilizing exothermic energy of a fuel cell and preventing deterioration in performance of a conductivity improving device. CONSTITUTION: A heat exchanger 35 for cooling blow-down water is installed in one piping path 34a of two piping paths 34a, 34b for taking out as blow-down water part of cooling water from a cell cooling water line 200 of a fuel cell 21. Flow rate of blow-down water having different temperature flowing in each piping path is controlled with motor operated valves 36a, 36b so that water temperature in an inlet of a conductivity improving device 26 for lowering conductivity exists within a specified range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water treatment system for fuel cell power generation equipment for suppressing the electric conductivity of cooling water for fuel cells.

[0002]

2. Description of the Related Art FIG. 7 is a system diagram showing a water treatment system of a conventional fuel cell power generation facility disclosed in, for example, Japanese Unexamined Patent Publication (Kokai) No. 5-315002, where 1 is a fuel cell,
Reference numeral 2 is a water vapor separator that separates the cooling water of the fuel cell 1 from water to water, 3 is a cell cooling water circulation pump that supplies the cell cooling water from the water vapor separator 2 to the fuel cell 1, and 100 is water that passes through the fuel cell 1. The battery cooling water system that handles the battery cooling water to be cooled and has the steam separator 2 and the battery cooling water circulation pump 3 is blowdown water from the steam separator 2 (cooling water taken out from the battery cooling water system to the water treatment system). Is referred to as blowdown water. The same shall apply hereinafter). 5 is a water receiving tank for storing the blowdown water and city water used as supplementary water, and 6 is the conductivity of the water stored in the water receiving tank. A conductivity improving device having a reverse osmosis membrane 7 for improving the conductivity and an ion exchange resin 8 for further improving the conductivity of the regenerated water that has passed through this film, and 9 is supplied from the water receiving tank 5 to the conductivity improving device 6. For supplying raw water, 10 is a makeup water supply pump for sending the regenerated water that has passed through the conductivity improving device 6 to the steam separator 2, 11 is a control valve for controlling the amount of makeup water according to the water level of the steam separator 2, and 12 is A heat exchanger that cools the water that flows through the conductivity improving device 6, and 13 is a safety valve for releasing the pressure when the outlet side pressure of the makeup water supply pump 10 rises.

Next, the operation will be described. Since the cell cooling water passes through the fuel cell 1 to cool it, the cell cooling water receives heat from the fuel cell 1 and becomes a gas-liquid mixed state, so that the steam separation gas 2
Come back to. In the steam separator 2, the cell cooling water in a gas-liquid mixed state is separated into gas and water, and only the liquid phase portion is sent to the fuel cell 1 by the cell cooling water circulation pump 3. The battery cooling water needs to have a low electric conductivity in order to prevent a ground fault of the battery and corrosion of the cooling pipe. Therefore, it is necessary to blow down part of the water in the steam separator 2 and replace it with water having a low conductivity. Generally, in order to save water, blowdown water is recycled through a water treatment system.

The blowdown water is blowdown water pipe line 4
It is collected in the water receiving tank 5 through the. The city water used as replenishment water and blowdown water are mixed and stored in the water receiving tank 5, and the water stored in the water receiving tank 5 is sent to the conductivity improving device 6 by the raw water pump 9 to form a reverse osmosis membrane. 7 and the ion exchange resin 8 improve the conductivity. Since the reverse osmosis membrane 7 has a low heat resistance of about 40 ° C. and the temperature of blowdown water is as high as about 170 ° C., the temperature is lowered by mixing city water supplemented in the water receiving tank 5, and the mixed water is further It is necessary to lower the temperature below a predetermined temperature by the heat exchanger 12. As cooling water for the heat exchanger 12, city water or industrial water is used. The regenerated water thus obtained is supplied by the makeup water supply pump 10.
The pressure is increased by and is returned to the water vapor separator 2. Usually, the steam in the steam separator 2 is also used as the raw material steam for reforming, so the water in the steam separator 2 is always consumed, and the consumed amount is used as makeup water in the water receiving tank 25.
It is supplied by city water mixed in and is replenished by a water treatment system. The amount of the makeup water is controlled by the control valve 11 so that the water level in the steam separator 2 is always constant. Due to the supplementary water that has been surplus by the control, the discharge pressure of the supplementary water supply pump 10 becomes high, and when it exceeds a predetermined value, it is discharged as surplus water by the safety valve 13.

[0005]

Since the conventional water treatment system for the fuel cell power generation facility is constructed as described above, it has the following problems. The water temperature at the entrance of the reverse osmosis membrane is not stable depending on the season because it depends on the temperature of city water mixed as supplementary water, city water for cooling the heat exchanger, or industrial water. If the temperature exceeds the upper limit of 40 ° C, the reverse osmosis membrane will not have an adequate desalting effect, and the reverse osmosis membrane will have an extremely short life, or the temperature will be too low and the water resistance of the reverse osmosis membrane will increase. However, there was a problem that the flow rate of water could not be secured, the amount of makeup water became insufficient, the water level of the steam separator dropped, and the entire fuel cell power generation facility stopped.

Further, since the makeup water returning to the steam separator has a low temperature and is directly supplied to the steam separator, it acts to lower the temperature of the steam separator and reduces the amount of heat retained. Therefore, there is a drawback that the amount of heat that can be taken out from the steam separator as excess heat is small and the total thermal efficiency is lowered. In addition, the water pressure after leaving the ion exchange resin depends on the degree of clogging of the reverse osmosis membrane and ion exchange resin, so the water pressure decreases at the end of the life of the reverse osmosis membrane and ion exchange resin, and the makeup water supply pump cavitation. And the pump was damaged. In addition, since the control valve regulates the amount of makeup water by the fluctuation of the water level of the water vapor separator, there is a drawback in that the amount of reclaimed water other than the required amount is discharged out of the system from the safety valve circuit, and the highly purified reclaimed water is wasted. It was

The present invention has been made to solve the above problems, and efficiently utilizes the heat generation energy of the fuel cell to prevent the performance of the conductivity improving device from deteriorating and to provide a highly efficient fuel. The objective is to obtain a water treatment system for battery power generation equipment.

[0008]

According to a first aspect of the present invention, there is provided a water treatment system for a fuel cell power generation facility, which is provided with a pipe line for taking out blowdown water and cooling the blowdown water taken out by being provided in the pipe line. The heat exchanger, the temperature detector for detecting the temperature of the water flowing to the conductivity improving device, and the temperature detected by the temperature detector, which is provided in the pipe, determines the flow rate of the blowdown water flowing through the pipe. It is equipped with a regulating valve.

According to a second aspect of the present invention, there is provided a water treatment system for a fuel cell power generation facility, which has a pipe passage for taking out blowdown water, a heat exchanger provided in the pipe passage for cooling the taken-down blowdown water, and a conductive material. A temperature detector for detecting the temperature of water flowing to the rate improving device, and a pipe for cooling water for cooling the heat exchanger are provided, and flow through the pipe for cooling water according to the temperature detected by the temperature detector. It is provided with a valve for adjusting the flow rate of cooling water of the heat exchanger.

According to a third aspect of the present invention, there is provided a water treatment system for fuel cell power generation equipment, wherein two or more pipe lines for taking out blowdown water are provided in at least one of the pipe lines. A heat exchanger for cooling down water, a temperature detector for detecting the temperature of water flowing through the conductivity improving device, and a pipe passage having the heat exchanger and a pipe passage having no heat exchanger are provided. A valve is provided for adjusting the flow rate of blowdown water flowing through the pipeline according to the temperature detected by the temperature detector.

According to a fourth aspect of the present invention, in a water treatment system for a fuel cell power generation facility, cooling of a heat exchanger provided in a pipe path for taking out blowdown water from a cell cooling water system is passed through a conductivity improving device. The replenishing water is returned to the battery cooling water system.

According to a fifth aspect of the present invention, in a water treatment system for a fuel cell power generation facility, a heat exchanger for exchanging heat between make-up water returned to the cell cooling water system and blowdown water taken out from the cell cooling water system is provided. It is provided.

According to a sixth aspect of the present invention, there is provided a water treatment system for a fuel cell power generation facility, which is provided with a heat exchanger for directly cooling the cooling water sent to the fuel cell with makeup water.

According to a seventh aspect of the present invention, there is provided a water treatment system for a fuel cell power generation facility, wherein an intermediate tank which is opened to atmospheric pressure and temporarily stores makeup water whose conductivity has been reduced through a conductivity improving device, and the intermediate tank A makeup water supply pump that returns the accumulated makeup water to the battery cooling water system is provided.

In the water treatment system of the fuel cell power generation facility according to claim 8 of the present invention, the surplus water overflowing from the path of the makeup water returned to the cell cooling water system by the makeup water supply pump is stored in the intermediate It is returned to the tank.

According to a ninth aspect of the present invention, there is provided a water treatment system for a fuel cell power generation facility, wherein a water receiving tank for temporarily storing blowdown water and new replenishing water is provided, and the replenishing water overflowing from the intermediate tank is supplied to the water receiving tank. To return.

[0017]

In the water treatment system for fuel cell power generation equipment according to claim 1 of the present invention, the heat exchanger provided in the pipe line for taking out the blowdown water cools the taken down blowdown water, A valve provided on the control valve adjusts the flow rate of the blowdown water flowing through the pipeline according to the output of the temperature detector that detects the temperature of the water flowing through the conductivity improving device, thereby communicating with the conductivity improving device. Control water temperature.

In the water treatment system for fuel cell power generation equipment according to claim 2 of the present invention, the heat exchanger provided in the pipe line for taking out the blowdown water cools the taken down blowdown water, and the heat exchange is performed. A valve provided in the cooling water piping of the heat exchanger measures the amount of cooling water of the heat exchanger flowing through the cooling water piping according to the output of the temperature detector that detects the temperature of the water flowing to the conductivity improving device. By adjusting, the temperature at which water passes through the conductivity improver is controlled.

According to a third aspect of the present invention, there is provided a water treatment system for a fuel cell power plant, wherein a heat exchanger provided in at least one of the two or more pipe lines for taking out the blowdown water has the pipe line. The temperature at which the blow-down water flowing through the pipe is cooled, and the valves provided in each of the pipeline having the heat exchanger and the pipeline having no heat exchanger detect the temperature of the water flowing to the conductivity improving device. Depending on the output of the detector, the flow rate of blowdown water flowing through the pipeline is adjusted to change the amount of cooled blowdown water and the amount of uncooled blowdown water, thereby improving conductivity. Controls the temperature of the water flowing through the device.

According to a fourth aspect of the present invention, in a water treatment system for a fuel cell power generation facility, cooling of a heat exchanger provided in a pipe line for taking out blowdown water from a cell cooling water system is passed through a conductivity improving device. The make-up water is returned to the battery cooling water system, and the heat exchanger cools the blowdown water and heats the make-up water.

In the water treatment system for fuel cell power generation equipment according to claim 5 of the present invention, the heat exchanger heats the makeup water returned to the cell cooling water system and the blowdown water taken out from the cell cooling water system. After replacement, the makeup water is heated and returns to the battery cooling water system, and the blowdown water is cooled and taken out.

In the water treatment system of the fuel cell power generation facility according to claim 6 of the present invention, the heat exchanger heat-exchanges between the cooling water sent to the fuel cell and the makeup water to be returned to the cell cooling water system. Then, the cooling water is further cooled and supplied to the fuel cell, and the makeup water is heated and returned to the cell cooling water system.

According to a seventh aspect of the present invention, in a water treatment system for a fuel cell power generation facility, an intermediate tank whose water surface is opened to atmospheric pressure temporarily stores and replenishes makeup water whose conductivity has been reduced through a conductivity improving device. The water supply pump sends the makeup water stored in the intermediate tank to the battery cooling water system without being affected by the water pressure at the outlet of the conductivity improving device.

In the water treatment system of the fuel cell power generation facility according to claim 8 of the present invention, the surplus water overflowing from the make-up water path returned to the cell cooling water system by the make-up water supply pump is stored in the middle of the place where the make-up water is stored. Return to the tank.

In the water treatment system for fuel cell power generation equipment according to claim 9 of the present invention, a water receiving tank for temporarily storing blowdown water and new replenishing water is provided, and the replenishing water overflowing from the intermediate tank is supplied to the water receiving tank. return.

[0026]

【Example】

Example 1. Hereinafter, Embodiment 1 of the present invention will be described with reference to FIG. In FIG. 1, 21-23, 25-31, 3
3 and 200 are conventional examples 1 to 3, 5 and 1
1, 13 and 100, 21 is a fuel cell, 22 is a steam separator for separating steam of cooling water of the fuel cell 21, and 23 is a steam separator 22 to the fuel cell 2.
Battery cooling water circulation pump for sending battery cooling water to 1, 20
0 is a battery cooling water system that handles the steam generated in the fuel cell 21 and has a steam separator 22 and a battery cooling water circulation pump 23; 25 is a city used as blowdown water taken out from the steam separator 22 and as supplementary water. A water receiving tank for mixing and storing water, 26 is a reverse osmosis membrane 27 for improving the electric conductivity of the water stored in the water receiving tank, and an ion exchange resin 28 for further improving the electric conductivity of the regenerated water that has passed through this membrane.
, 29 is a raw water pump for sending water from the water receiving tank 25 to the conductivity improving device 26, and 30 is makeup water supply for sending regenerated water passing through the conductivity improving device 26 to the steam separator 22. A pump, 31 is a control valve for controlling the amount of makeup water according to the water level of the steam separator 22, and 33 is a safety valve for releasing the pressure when the outlet side pressure of the makeup water supply pump 30 rises.

Further, in FIG. 1, 34 to 37 are the first embodiment.
34a and 34b are blowdown water pipe lines for extracting blowdown water from the steam separator 22, and 35 is provided in the blowdown water pipe line 34a. These pipe lines are provided by city water or industrial water. Heat exchangers 36a, 36b for cooling the blowdown water passing therethrough
Is a motor-operated valve provided in each of the blowdown water pipes 34a, 34b, and 37 is a temperature detector for detecting the water temperature at the inlet of the conductivity improving device 26.

Next, the operation will be described. Similar to the conventional example, the water treatment system for fuel cell equipment according to the first embodiment is
The cell cooling water, which has a function of cooling water by passing through the fuel cell 21, is separated and stored in the steam separator 22 in the cell cooling water system 200. In order to prevent the ground fault of the battery and the corrosion of the cooling pipe, this battery cooling water takes out a part of the liquid layer portion of the steam separator 22 as blowdown water, and has a low conductivity through the conductivity improving device 26. It is regenerated into water and replaced.

Since the steam in the steam separator 22 is sent to the reformer by utilizing the surplus heat, the steam is maintained at a high temperature of about 170 ° C., and the blowdown water as the liquid layer portion has the same temperature. Is kept. However, the reverse osmosis membrane 27 in the conductivity improving device 26 that regenerates the conductivity small.
The performance deteriorates when water having a high temperature of 40 ° C. or higher is passed through, and thus needs to be cooled. In addition, depending on the season, this cooling may be excessive and the water flow resistance of the reverse osmosis membrane 27 may increase, so that the required water flow rate may not be secured. Therefore, the blowdown water taken out from the steam separator 22 is branched into two pipe lines 34a and 34b, one of the blowdown water pipe lines 34a is provided with a heat exchanger 35 for cooling, and the other blowdown water is cooled. The water pipe line 34b is supplied as it is without a heat exchanger, and the flow rate of blowdown water in these pipe lines is adjusted by the electric valves 36a and 36b provided in the pipe lines 34a and 34b, respectively, and the mixed water is adjusted. Water tank 2
Try to store in 5. In order to supplement the amount of water consumed by the steam from the steam separator 22 to the reformer in the water receiving tank 25, the blowdown water is mixed with city water as supplementary water, and the raw water pump 29 causes the water receiving tank 25 to mix.
The water stored in the water is sent to the conductivity improving device 26, and the conductivity is improved through the reverse osmosis membrane 27 and the ion exchange resin 28.

The temperature detector 37 is the conductivity improving device 2
The temperature of the water passed to 6 is detected at the entrance. Due to the detected temperature, the blowdown water piping 34a,
If the temperature becomes lower than the required temperature, the motor-operated valves 36a and 36b provided on the motor-operated valve 36a
When the valve opening of the motor-operated valve 36b is changed to the closing direction and the valve opening of the motor-operated valve 36b is changed to the opening direction, and when this temperature becomes higher than the required temperature, the valve opening of the motor-operated valve 36a is changed. In the opening direction, the valve opening of the motor-operated valve 36b is changed so as to be in the closing direction, the flow rate of the blowdown water passing through the respective pipelines 34a, 34b is adjusted, and the water is stored in the water receiving tank 25. In the receiving tank 25, city water is further mixed as supplementary water,
This replenishment is a constant amount according to the consumption amount of steam sent from the steam separator 22 to the reformer and the like, and the water temperature of the city water is a constant temperature in the period of the cycle of the valve control described above. The mixing of the replenishment water works to lower the temperature of the water in the water receiving tank 25 by a constant temperature. Since the mixed water in the water receiving tank 25 is sent to the conductivity improving device 26 by the raw water pump 29, the water temperature at the inlet of the conductivity improving device 26 is controlled to fall within a predetermined range.

As described above, according to the first embodiment, the temperature of the water passing through the reverse osmosis membrane 27 of the conductivity improving device 26 can be maintained at an appropriate temperature for maintaining the performance of the reverse osmosis membrane. It is possible to avoid an increase in the water resistance of the reverse osmosis membrane 27 due to the low water temperature, and without causing a shortage of the amount of regenerated water, that is, the amount of makeup water.
There is an effect that an inadvertent plant trip can be avoided, and conversely, deterioration of the reverse osmosis membrane 27 due to high water temperature can be prevented and the life of the reverse osmosis membrane 27 can be extended.
Furthermore, since the motorized valves 36a and 36b are controlled so as to control the temperature to a predetermined temperature by changing the mixing ratio of the cooled blowdown water and the high temperature blowdown water as it is, the total amount taken out as blowdown water. There is an effect that the water flow temperature of the conductivity improving device 26 can be controlled while keeping the above constant.

In the first embodiment, the flow rate of blowdown water is adjusted by the valve opening of the motor-operated valves 36a and 36b provided in the pipe lines 34a and 34b. May be a solenoid valve, and in this case, when this temperature becomes lower than the required temperature due to the temperature detected by the temperature detector 37, the solenoid valve 36a
Is closed and the solenoid valve 36b is opened. When this temperature becomes higher than the required temperature, the solenoid valve 36a is opened.
By switching the electric valve 36b to the closed state, the same effect as that of the first embodiment can be obtained.

In the first embodiment, the flow rate of the blow-down water is adjusted to control the water flow temperature of the conductivity improving device 26. However, the flow rate of city water or industrial water for cooling the heat exchanger 35 is controlled. The water temperature may be controlled by changing the heat exchange rate of the heat exchanger 35 by adjusting the. That is, the conductivity improving device 26 in which the temperature detector 37 detects the opening degree of the motor-operated valve provided in the cooling water side piping of the heat exchanger 35.
By adjusting according to the water temperature at the entrance of the, it is possible to obtain the same effect as in the first embodiment.

Embodiment 2 FIG. FIG. 2 is a system diagram showing a water treatment system of a fuel cell power generation facility according to a second embodiment of the present invention. In contrast to the system diagram of FIG. In place of the heat exchanger 35 using, the heat exchanger 38 using makeup water to be returned to the steam separator 22 is provided. The blow-down water just taken out maintains the internal temperature of the steam separator 22 of about 170 ° C., while at the entrance of the conductivity improving device 26,
Since the reverse osmosis membrane 27 is maintained at a temperature of 40 ° C. or lower as described in Example 1 above, the temperature of the makeup water is kept lower than that of the blowdown water. The heat exchanger 38 exchanges heat between these waters.

Therefore, in the second embodiment, in addition to the effect described in the first embodiment, the temperature of the makeup water is increased to increase the temperature of the water vapor separator 2
Since the difference between the temperature of No. 2 and the makeup water temperature is reduced and then returned to the steam separator 22, the heat quantity of the steam separator 22 can be used more effectively than before, that is, the surplus heat increases and the fuel cell There is an effect that a high total thermal efficiency can be obtained for the entire power generation facility.

Example 3. 3 is a system diagram showing a water treatment system for a fuel cell power generation facility according to a third embodiment of the present invention. In addition to the system diagram shown in FIG. In addition, an intermediate tank 39 for temporarily storing the reclaimed water treated by the device 26 is provided. The reclaimed water processed through the conductivity improving device 26 is temporarily stored in the intermediate tank 39. The water surface of the intermediate tank 39 is open to the atmospheric pressure, and the makeup water supply pump 30 takes in the regenerated water stored in the intermediate tank 39 and sends it as makeup water to the steam separator 22 via the heat exchanger 38. The makeup water supply pump 30 is operated when the water level in the intermediate tank 39 is above a predetermined level, and is stopped when the water level is below a predetermined level. Further, the reclaimed water overflowing from the intermediate tank 39 is drained.

As described above, according to the third embodiment, in addition to the effects described in the first and second embodiments, the inlet pressure of the makeup water supply pump 30 is always maintained at atmospheric pressure and the inlet flow rate is kept constant. Since this is ensured, the reverse osmosis membrane 27 and the ion exchange resin 28 of the conductivity improving device 26 are clogged, the water pressure at the outlet of the conductivity improving device 26 decreases, the flow rate of the makeup water supply pump 30 is insufficient, and the inlet pressure negative pressure is reduced. It is possible to prevent cavitation due to the above, and to prevent an accidental failure of the pump. Also, the change in the required amount of makeup water is
Since it can be absorbed by the intermediate tank 39, the amount of reclaimed water that has passed through the conductivity improving device 26 can always be kept constant, and the conductivity improving device 26 can instantaneously reach the maximum required water amount. You don't have to have a combined playback capability,
The effect is that the capacity can be reduced.

Example 4. 4 is a system diagram showing a water treatment system of a fuel cell power generation facility according to a fourth embodiment of the present invention. In addition to the system diagram of FIG. 3 showing the third embodiment, surplus water discharged from the safety valve 33 is shown. A surplus water channel 40 for returning the water to the intermediate tank 39 is provided. The amount of water consumed by the water vapor separator 22 varies depending on the power generation output of the fuel cell, and even if the output is constant, there is a deviation in the control timing of the amount of consumed water and the amount of supplied water, so it constantly fluctuates. Therefore, the amount of make-up water is controlled by the control valve 31 that adjusts the flow rate of make-up water so that the water level of the steam separator 22 becomes constant. When the required amount of make-up water in the steam separator 22 is small, the make-up water becomes excessive and the discharge pressure of the make-up water supply pump 30 becomes abnormally high. Therefore, a safety valve 33 is provided to release the pressure. Excess water is escaping from the circuit. However, in the conventional water treatment system, since this surplus water was discharged to the outside of the system, the high-purity reclaimed water was wasted.

In the fourth embodiment, a surplus water channel 40 for returning surplus water discharged from the safety valve 33 to the intermediate tank 39 is provided,
The surplus water is reused by returning it to the intermediate tank 39 and storing it. With this configuration, according to the fourth embodiment,
In addition to the effect described in the third embodiment, the surplus water discharged from the safety valve 33 is returned to the intermediate tank 39. Therefore, due to fluctuations in the demand for makeup water, high-purity regenerated water with improved conductivity is wastefully surplus. It has the effect of not being thrown away as water.

Example 5. FIG. 5 is a system diagram showing a water treatment system of a fuel cell power generation facility according to a fifth embodiment of the present invention. In addition to the system diagram of FIG. The overflow water channel 41 returning to the water receiving tank 25 is provided. The surplus reclaimed water stored in the intermediate tank 39 varies in water level due to excess and deficiency of the supply amount and the consumption amount, but when it overflows, it is wasted if discarded, and is returned to the water receiving tank 25 through the overflow water channel 41. As described above, according to the fifth embodiment, in addition to the effects described in the first to fourth embodiments, the water tank 2
Since the amount of city water to be replenished to 5 is small and the purity is higher than that of city water, the life of the reverse osmosis membrane 27 and the ion exchange resin 28 is extended.

Example 6. 6 is a system diagram showing a water treatment system of a fuel cell power generation facility according to a sixth embodiment of the present invention. In addition to the system diagram of FIG. A heat exchanger 42 for cooling the battery cooling water with makeup water is provided in the middle of the circuit for supplying the battery cooling water. In order to maintain the operating temperature of the fuel cell 21, the cell cooling water temperature is set to the required temperature (about 15
However, in the conventional water treatment system, the only method is to control the cooling water temperature of the steam separator 22. However, the surplus heat of the steam separator 22 is used for exhaust heat such as being used in a double-effect absorption refrigerator.
It is necessary to keep the battery cooling water temperature at the required temperature while keeping the temperature level of the water in the steam separator 22 as high as possible.

Therefore, in the sixth embodiment, the heat exchanger 42 provided in the battery cooling water circuit cools only the battery cooling water by using the makeup water branched from the makeup water channel. Thus, according to the sixth embodiment, in addition to the effects described in the first to fifth embodiments, in the heat exchanger 42, the temperature of the makeup water returned to the steam separator 22 is increased and the battery cooling water is removed. Since the cooling is performed, it is possible to keep the cell cooling water at a low temperature while keeping the heat quantity of the steam separator 22 high, and it is possible to obtain higher overall thermal efficiency as the entire fuel cell power generation facility than in the other examples. effective.

[0043]

Since the present invention is constructed as described above, it has the following effects.

According to the water treatment system of the fuel cell power generation facility according to claim 1 of the present invention, the heat exchanger provided in the pipe line for taking out the blowdown water cools the taken down blowdown water, The valve provided in the pipeline adjusts the flow rate of the blowdown water flowing through the pipeline according to the output of the temperature detector that detects the temperature of the water flowing through the conductivity improver. The temperature of the water flowing through
There is an effect that the temperature can be maintained at an appropriate temperature for maintaining the performance of the conductivity improving device.

According to the water treatment system of the fuel cell power generation facility according to claim 2 of the present invention, the heat exchanger provided in the pipe line for taking out the blowdown water cools the blowdown water taken out, A valve provided on the cooling water piping of the heat exchanger cools the heat exchanger flowing through the cooling water piping according to the output of the temperature detector that detects the temperature of the water flowing to the conductivity improving device. Since the water flow rate is adjusted, there is an effect that the temperature of the water passing through the conductivity improving device can be maintained at an appropriate temperature for maintaining the performance of the conductivity improving device.

According to the third aspect of the present invention, in the fuel cell power plant water treatment system, the heat exchanger provided in at least one of the two or more pipe lines for taking out the blowdown water is Cooling the blowdown water flowing through the pipeline, the valves provided in each of the pipeline having the heat exchanger and the pipeline not having the heat exchanger detect the temperature of the water flowing to the conductivity improving device. According to the output of the temperature detector, the flow rate of the blowdown water flowing through the pipe is adjusted to change the amount of each of the cooled blowdown water and the uncooled blowdown water. The temperature of the water passing through the improvement device can be maintained at an appropriate temperature for maintaining the performance of the conductivity improvement device, and further, the cooled blowdown water and the high temperature blowdown water as it is are mixed. Rate By controlling the valve so that the temperature is controlled to a predetermined temperature by controlling the flow rate, it is possible to control the water temperature of the conductivity improving device while keeping the total amount of blowdown water taken out constant. There is an effect.

According to the fourth aspect of the present invention, in the water treatment system for the fuel cell power generation facility, the cooling of the heat exchanger provided in the pipe line for taking out the blowdown water is passed through the conductivity improving device to pass through the battery. The make-up water is returned to the cooling water system, and the heat exchanger cools the blowdown water and heats the makeup water, so the temperature of the makeup water is raised to increase the temperature of the battery cooling water system and the makeup water temperature. There is an effect that the difference between the two can be reduced and the amount of heat possessed by the battery cooling water system can be effectively used.

According to the water treatment system of the fuel cell power generation facility according to the fifth aspect of the present invention, the heat exchanger is provided between the makeup water returned to the battery cooling water system and the blowdown water taken out from the battery cooling water system. , The makeup water is heated and returns to the battery cooling water system, and the blowdown water is cooled and taken out, so the temperature of the makeup water is increased and the difference between the temperature of the battery cooling water system and the makeup water temperature is increased. It is possible to effectively use the amount of heat possessed by the battery cooling water system by reducing the above.

According to the water treatment system of the fuel cell power generation facility according to the sixth aspect of the present invention, the heat exchanger heats the cooling water supplied to the fuel cell and the makeup water returned to the cell cooling water system. After replacement, the cooling water is further cooled and supplied to the fuel cell, and the make-up water is heated and returned to the battery cooling water system, so the temperature of the battery cooling water is kept low while keeping the heat quantity of the battery cooling water system high. Therefore, there is an effect that high overall thermal efficiency can be obtained for the entire fuel cell power generation facility.

According to the seventh aspect of the present invention, in the water treatment system for a fuel cell power plant, the intermediate tank whose water surface is open to the atmospheric pressure temporarily stores makeup water whose conductivity has been reduced through the conductivity improving device. , The makeup water supply pump sends the makeup water stored in the intermediate tank to the battery cooling water system without being affected by the water pressure at the outlet of the conductivity improving device, so that the water pressure at the outlet of the conductivity improving device is It is possible to prevent a decrease in flow rate, insufficient flow rate of the makeup water supply pump, and cavitation due to the negative pressure of the inlet pressure. Further, since the fluctuation of the required amount of makeup water can be absorbed by the intermediate tank, the amount of reclaimed water that has passed through the conductivity improving device can be kept constant, and the conductivity improving device can instantaneously There is no need to have a regeneration capacity that matches the required maximum amount of water, and there is an effect that the capacity can be reduced.

According to the eighth aspect of the present invention, there is provided the water treatment system for the fuel cell power generation facility, wherein the surplus water overflowing from the makeup water route returned from the makeup water supply pump to the cell cooling water system is stored in the makeup water. Since it is returned to the intermediate tank, there is an effect that high-purity reclaimed water with improved conductivity is not wasted due to fluctuations in the demand for makeup water.

According to the ninth aspect of the present invention, there is provided the water treatment system for the fuel cell power generation facility, which is provided with a water receiving tank for temporarily storing blowdown water and new replenishing water, and receives the replenishing water overflowing from the intermediate tank. Since the water is returned to the water tank, the amount of replenishing water to be replenished to the water receiving tank is small, and since the purity is high, the life of the conductivity improving device is extended.

[Brief description of drawings]

FIG. 1 is a systematic diagram of a water treatment system for fuel cell power generation equipment showing Embodiment 1 of the present invention.

FIG. 2 is a system diagram of a water treatment system for fuel cell power generation equipment showing Embodiment 2 of the present invention.

FIG. 3 is a system diagram of a water treatment system for fuel cell power generation equipment showing Embodiment 3 of the present invention.

FIG. 4 is a system diagram of a water treatment system for fuel cell power generation equipment showing Embodiment 4 of the present invention.

FIG. 5 is a system diagram of a water treatment system for fuel cell power generation equipment showing Embodiment 5 of the present invention.

FIG. 6 is a systematic diagram of a water treatment system for fuel cell power generation equipment showing Embodiment 6 of the present invention.

FIG. 7 is a system diagram showing a water treatment system of a conventional fuel cell power generation facility.

[Explanation of symbols]

21 Fuel Cell 25 Water Tank 26 Conductivity Improvement Device 30 Makeup Water Supply Pump 34a, 34b Blowdown Water Pipeline 35
Heat exchanger 36a, 36b Motorized valve 37
Temperature detector 38 Heat exchanger 39 Intermediate tank 40 Excess water channel 41 Overflow water channel 42 Heat exchanger 200 Battery cooling water system

Claims (9)

[Claims] 1. A part of cooling water is taken out as blowdown water from a cell cooling water system of a fuel cell, and the blowdown water and new supplementary water are passed through a conductivity improving device to reduce the conductivity. In the water treatment system of the fuel cell power generation facility for returning to the battery cooling water system as make-up water, a pipe passage for taking out the blowdown water, a heat exchanger provided in the pipe passage for cooling the taken down blowdown water,
A temperature detector for detecting the temperature of water flowing through the conductivity improving device, and a valve provided in the pipe line for adjusting the flow rate of blowdown water flowing through the pipe line according to the temperature detected by the temperature detector. A water treatment system for a fuel cell power generation facility, which is characterized by being provided. 2. A part of cooling water is taken out as blowdown water from a cell cooling water system of a fuel cell, and the blowdown water and new replenishing water are passed through a conductivity improving device to reduce the conductivity. In the water treatment system of the fuel cell power generation facility for returning to the battery cooling water system as make-up water, a pipe passage for taking out the blowdown water, a heat exchanger provided in the pipe passage for cooling the taken down blowdown water,
A temperature detector for detecting the temperature of water flowing through the conductivity improving device, and a pipe for cooling water for cooling the heat exchanger, and a pipe for the cooling water depending on the temperature detected by the temperature detector. A water treatment system for a fuel cell power generation facility, which is provided with a valve for adjusting a flow rate of cooling water of a heat exchanger flowing through the water. 3. A part of cooling water is taken out as blowdown water from a cell cooling water system of a fuel cell, and the blowdown water and new replenishing water are passed through a conductivity improving device to reduce the conductivity. In the water treatment system of the fuel cell power generation facility for returning to the battery cooling water system as make-up water, at least one of the two or more pipe lines for taking out the blowdown water and the pipe line is provided and taken out. A heat exchanger for cooling blowdown water, a temperature detector for detecting the temperature of water flowing in the conductivity improving device, and a pipeline having the heat exchanger, and a pipeline having no heat exchanger, respectively. A water treatment system for a fuel cell power generation facility, comprising a valve provided to adjust the flow rate of blowdown water flowing through the pipeline according to the temperature detected by the temperature detector. 4. A heat exchanger provided in a pipe line for taking out blowdown water from the battery cooling water system is cooled by makeup water which passes through a conductivity improving device and is returned to the battery cooling water system. The water treatment system for fuel cell power generation equipment according to claim 1 or 3. 5. A part of cooling water is taken out as blowdown water from a cell cooling water system of a fuel cell, and the blowdown water and new replenishing water are passed through a conductivity improving device to reduce the conductivity. In a water treatment system of a fuel cell power generation facility for returning as make-up water to the cell cooling water system, a fuel cell power generation characterized by comprising a heat exchanger for exchanging heat between the make-up water and the blowdown water. Equipment water treatment system. 6. A part of cooling water is taken out as blowdown water from a cell cooling water system of a fuel cell, and the blowdown water and new replenishment water are passed through a conductivity improving device to reduce the conductivity. In the water treatment system of the fuel cell power generation facility for returning to the battery cooling water system as make-up water, a heat exchanger for directly cooling the cooling water sent to the fuel cell by the make-up water is provided. Water treatment system for fuel cell power generation equipment. 7. A part of cooling water is taken out as blowdown water from a cell cooling water system of a fuel cell, and the blowdown water and new supplementary water are passed through a conductivity improving device to reduce the conductivity. In the water treatment system of the fuel cell power generation facility for returning as make-up water to the cell cooling water system, an intermediate tank which is opened to atmospheric pressure and temporarily stores make-up water whose conductivity has been reduced through the conductivity improving device, and this intermediate tank A water treatment system for a fuel cell power generation facility, comprising a makeup water supply pump for returning makeup water stored in the cell cooling water system. 8. The fuel cell power generation according to claim 7, wherein the surplus water overflowing from the makeup water path returned to the cell cooling water system by the makeup water supply pump is returned to the intermediate tank storing the makeup water. Equipment water treatment system. 9. The water receiving tank for temporarily storing blowdown water and new replenishing water is provided, and the replenishing water overflowing from the intermediate tank is returned to the water receiving tank.
The water treatment system of the fuel cell power generation facility described.