JPH0158479B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to medium-temperature power generation equipment for a nuclear power plant that uses a non-regenerative heat exchanger of a reactor coolant purification system of a boiling water nuclear power plant as a heat source.

In boiling water nuclear power plants, reactor feed water is supplied after being purified from the turbine main condenser through a condensate demineralizer, but in order to maintain high core purity at all times, There is a reactor coolant purification system that continuously removes and purifies a portion of the reactor coolant from the reactor recirculation system.

Figure 1 is a system diagram of a conventional reactor coolant purification system, in which a part of the reactor coolant is transferred from the reactor recirculation system piping 2 connected to the reactor pressure vessel 1 to the reactor coolant purification system circulation pump. 3, and after being cooled sequentially through a regenerative heat exchanger 4 and a non-regenerative heat exchanger 5, it is introduced into a filtration demineralizer 6 for purification, and then heated again through a regenerative heat exchanger 4. The water is returned to the reactor pressure vessel 1 via a water supply pipe 7 from (omitted). The reason why the extracted reactor coolant is passed twice from the regenerative heat exchanger 4 to the non-regenerative heat exchanger 5 is that the temperature of the reactor coolant processed by the filtration demineralizer 6 is high enough to function properly. Because it does not demonstrate
This is because it is necessary to cool the temperature to 60° C. or lower, which is the operating temperature of the filtration demineralizer 6.

Of the above two sets of heat exchangers, the regenerative heat exchanger 4 is cooled by the reactor coolant purified by the filtration demineralizer 6, and the thermal energy at that time is transferred to the reactor pressure vessel 1. The non-regenerative heat exchanger 5 is used to warm the reactor coolant that is returned, but the non-regenerative heat exchanger 5 is cooled by cooling water from the reactor auxiliary cooling water system 8, and after cooling, it is directly transported to the ocean or river. Since the heat exchangers are disposed of in other places, there is a problem in terms of energy conservation, and there has been a demand for energy recovery measures for these non-regenerative heat exchangers.

This invention has been made in view of the above circumstances, and in a non-regenerative heat exchanger used in a reactor coolant purification system of a boiling water nuclear power plant, the reactor auxiliary cooling water system is used for cooling. A low boiling point medium such as chlorofluorocarbons is used instead of cooling water, and the low boiling point medium steam is evaporated into steam by the heat of the other side during cooling, and the low boiling point medium steam is used to operate the low boiling point medium turbine, and the turbine is connected to a generator. The purpose of the present invention is to provide medium-temperature power generation equipment for nuclear power plants that connects the two to generate power and recover the thermal energy that was previously discarded as electrical energy.

An embodiment of the medium-temperature power generation equipment for a nuclear power plant according to the present invention will be explained with reference to the system diagram shown in FIG. In FIG. 2, a circulation pump 10, a regenerative heat exchanger 11, a non-regenerative heat exchanger 12, a filtration demineralizer 1
3 constitutes a reactor coolant purification system 14, in which a part of the reactor coolant is taken out by a circulation pump 10 from a reactor recirculation system piping 15 connected to a reactor pressure vessel (not shown in the drawing). Regenerative heat exchanger 11
and a filtration demineralizer 13 through a non-regenerative heat exchanger 12
After cooling to the proper operating temperature of the filtration demineralizer 13
After passing through the regenerative heat exchanger 11 and warming it, the water supply pipe 1 is connected from the reactor condensate system (not shown in the drawing) to the reactor pressure vessel (not shown in the drawing).
It's back to 6.

The reactor coolant sent by the circulation pump 10 is purified by the filtration demineralizer 13 in the regenerative heat exchanger 11, and the reactor coolant is returned to the water supply pipe 16, which removes heat. After being cooled to a temperature of For cooling at 12, a low boiling point medium such as fluorocarbon or ammonia is used. The low boiling point medium is heated and evaporated while passing through the cooling heat transfer tube 17 of the non-regenerative heat exchanger 12, and the generated low boiling point medium vapor is led to the low boiling point medium turbine 18 and drives this turbine 18. death,
A generator 19 connected to the low boiling point medium turbine 18 is rotated to generate electricity. The low boiling point medium vapor that has finished its work in the low boiling point medium turbine 18 is sent to the condenser 2.
0, is cooled by the cooling water from the reactor auxiliary cooling water system 21, becomes liquid, and is supplied to the liquid supply pump 22.
The pressure is increased by the liquid supply pipe 26, and the liquid is again sent to the cooling heat exchanger tube 17 of the non-regenerative heat exchanger 12 of the reactor coolant purification system. Furthermore, when repairing the low boiling point medium turbine 18 or the generator 19,
In order to direct the low-boiling medium vapor directly to the condenser 20,
A turbine bypass valve 23 and a bypass pipe 24 connecting the turbine bypass valve 23 are provided. Further, a low boiling point medium storage tank 25 for storing a liquid low boiling point medium is connected to the liquid supply pipe 26 via a connecting pipe 27.

The intermediate temperature power generation equipment for a nuclear power plant according to the present invention has the following features, as described in detail in the embodiments above:
In the reactor coolant purification system of a boiling water nuclear power plant, a low boiling point medium such as Freon is used to recover the heat to cool the non-regenerative heat exchanger;
The generated low-boiling medium steam drives a turbine generator and converts it into electrical energy, which is used for internal power, etc., which saves a large amount of thermal energy that was previously disposed of through the reactor auxiliary cooling water system. It has the advantage that parts can be recovered. In addition, the cooling water of the reactor auxiliary cooling water system is also used in the medium-temperature power generation equipment of the nuclear power plant according to the present invention to liquefy the low-boiling medium vapor, but the cooling water of the reactor auxiliary cooling water system is Since the amount required is small compared to the amount used for cooling the regenerative heat exchanger, it has the effect of reducing the burden on the reactor auxiliary equipment cooling water system.

[Brief explanation of drawings]

Figure 1 is a system diagram of a conventional reactor coolant purification system.
FIG. 2 is a system diagram of a medium-temperature power generation facility in a nuclear power plant in an embodiment of the present invention. 12, 5...Non-regenerative heat exchanger, 14...Reactor coolant purification system, 18...Low boiling point medium turbine, 1
9... Generator, 20... Condenser, 21, 8... Reactor auxiliary cooling water system, 22... Liquid supply pump, 23...
...Turbine bypass valve, 25...Low boiling point medium storage tank, 26...Liquid supply piping, 27...Connection piping.

Claims (1)

[Claims] 1. In the reactor coolant purification system of a boiling water nuclear power plant, a low boiling point medium is used to cool the non-regenerative heat exchanger, and the system is driven by the low boiling point medium vapor generated in the non-regenerative heat exchanger. a low boiling point medium turbine, a generator rotated by the low boiling point medium turbine, a condenser that cools and liquefies the low boiling point medium vapor that has finished work in the low boiling point medium turbine, and a low boiling point medium vapor that has become a liquid. a liquid supply pump that sends a medium to the non-regenerative heat exchanger via a liquid supply pipe; a low boiling point medium storage tank that is connected to the liquid supply pipe via a connecting pipe and stores a liquid low boiling point medium; and a low boiling point medium. a bypass pipe line that bypasses the low-boiling point medium turbine and directly leads the steam to the condenser via the turbine bypass valve, the low-boiling point medium being used for cooling the non-regenerative heat exchanger of the reactor coolant purification system. This is a medium-temperature power generation facility at a nuclear power plant that uses water as a working medium to generate electricity.