JPH02287295A - Purification and recovery method of filling water for periodic inspection - Google Patents

Abstract

PURPOSE:To make possible higher purification and the reduction of a recovery time by allowing periodical inspection filling water to introduce in the suction side of a condensate pump of a turbine system to pressurize so as to purify by a condensate filter and a demineralizer. CONSTITUTION:Filling water reserved in a reactor well 2, a device temporarily- put pool and a fuel pool 3 is pressurized by a fuel pool cooling purification system pump 6 through drain tubing 5 to purify by a fuel pool cooling purification system filtration demineralizer 7 so as to introduce to a condensate pump 13 of a turbine system through a filling water transfer tube 17. And the water 4 pressurized by the pump 13 is successively purified by a condensate filter 14 and a condensate demineralizer 15 to recover in a condensate storage tank 8 through spillover tubing 16. At this time, since each device 14, 15 has a sufficient purification capability and a treatment capacity, the water 4 is directly introduced in the pump 13 through a bypass tube 18 and the transfer tube 17 and can be purified by the devices 13, 14 alone. By this device, the filling water is highly treated in a shorter time to reduce a recovery time sharply.

Description

[Detailed Description of the Invention] [Object of the Invention] (Field of Industrial Application) The present invention relates to a method for purifying and recovering water for periodic inspection in a nuclear power plant, and particularly for cleaning and recovering water that is highly contaminated. The present invention relates to a method for purifying and collecting water for periodic inspections, which can purify the water and greatly shorten the collection time of the water.

(Prior art) The equipment that makes up a nuclear power plant is required to be periodically inspected depending on its importance. During these periodic inspections, the equipment is disassembled and each component is inspected for damage. The work to confirm the above will be strictly carried out.

For example, when conducting periodic inspections of nuclear reactor equipment, the top cover of the reactor pressure vessel 1 is removed as shown in Figure 3, and the steam dryer, steam/moisture #1 container, etc. housed inside the pressure vessel are removed. Structures, fuel assemblies, etc. are taken out. All of these structures are contaminated with high levels of radioactivity, and in order to protect inspectors engaged in inspection work from radiation, water with a high radiation shielding effect was poured into the reactor well 2,
A temporary equipment storage pool and a fuel pool 3 are filled, and structures and the like are immersed in the filled water 4 and moved, temporarily placed at a predetermined position, and stored.

Condensate water is generally used as the filling water 4.

When the inspection work and replacement work for the reactor internal structures and fuel assemblies are completed, it is necessary to drain the water 4 stored in the reactor well 2, equipment temporary storage pool, and fuel pool 3. Water stored in these pools 4
The eight most are approximately 2,000, depending on the plant size.
It extends to nl.

A conventional method for purifying and collecting water 4 is performed according to the following procedure. That is, first, the water drain pipe 5 connected to the reactor well 2, the equipment temporary storage boule, and the bottom of the fuel pool 3 is
The filled water 4 is handled by the fuel pool cooling purification system pump 6 via the filtration desalination device 7 of the fuel pool cooling purification system.
Transfer to. After purification by removing contaminants such as crud contained in the charged water 4 using the filtration and demineralization device 7, the treated water was collected into the condensate storage tank 8. The recovered treated water is again sent to the fuel pool 3 etc. by the condensate transfer pump 9, and is circulated and used.

In addition, in recent nuclear power plants, in order to further reduce the IM of inspection H during inspections, the water quality of the water stored in the condensate storage tank 8, which serves as J3 and reactor make-up water, has been improved as shown in Figure 4. A method of purifying and recovering the filled water 4 by the method shown in is also adopted.

That is, the filled water 4 stored in the reactor well 2, equipment pool and fuel pool 3 and contaminated by periodic inspection is purified by the fuel pool cooling purification system filtration desalination device 7, and then - Chicombour surge tank 10
A method is adopted in which the condensate is stored in the condensate storage tank 8, then further treated in the waste treatment stage (!11), and then recovered in the condensate storage tank 8.

(Problems to be Solved by the Invention) However, in the conventional method for purifying and collecting water shown in Fig. 3, the processing capacity of the filtration desalination device of the fuel pool cooling purification system is insufficient, so it is necessary to perform sufficient purification. was difficult.

On the other hand, in the conventional purification and recovery method shown in Figure 4, a two-stage treatment of water is carried out using a filtration desalination device in the fuel pool cooling purification system and waste treatment equipment, which removes pollutants. It has become possible to significantly improve the rate.

However, the processing time in waste treatment equipment is extremely long;
In addition to significantly increasing the recovery time for filled water, during regular inspections of nuclear plants, waste fluids generated from other systems are concentrated, and since the filling water is treated together with these waste fluids, the load on the waste treatment system is rapidly increasing. This may make efficient purification and recovery difficult.

The present invention has been made to solve the above-mentioned problems, and provides a periodic inspection tank that can purify periodic inspection water to a higher degree and significantly shorten the collection time. The purpose is to provide a water purification and recovery method.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides water for periodic inspection that is stored in a reactor well, equipment temporary storage boule, and fuel boule during a periodic inspection of a nuclear power plant equipped with a turbine system. In the purification and recovery method, the above-mentioned filled water is introduced into the suction α+II of a condensate pump of a turbine system, and the introduced water is added with soil by the condensate pump and sent to the condensate filtration and condensate desalination equipment. It is characterized in that after the water is passed through and purified, the purified water is collected into the condensate storage tank via the spill A-bar piping.

In addition, the fill water is extracted from any of the piping systems of the fuel pool cooling and purification system, reactor recirculation system, residual heat removal system, and reactor coolant purification system and introduced into the suction side of the condensate pump of the turbine system. That's good.

(Function) According to the method for purifying and recovering fill water for periodic inspections according to the above configuration, the fill water stored in the reactor well, temporary equipment boule rB, and fuel boule is transferred to the suction side of the condensate pump of the turbine system. be introduced. The introduced water is pressurized by a condensate pump, highly purified by a turbine-based condensate i11'A device and a condensate desalination device, and then recovered into a condensate storage tank via spillover piping.

Here, we will compare turbine-based condensate filtration equipment and condensate desalination equipment with filtration and desalination equipment for fuel pool cooling and purification systems, and filtration and desalination equipment for waste treatment systems. I! Since the barber's arrogance is much greater and the removal rate of contaminants is also high, it becomes possible to treat the water to a high degree within a short period of time, and the time for collecting the water to be collected can be significantly shortened.

Furthermore, since the waste treatment equipment is bypassed and the water is purified, the load on the waste treatment system during periodic inspections can be reduced.

(Example) Next, an example of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a system diagram showing an embodiment of the method for purifying and recovering water for periodic inspection according to the present invention. Note that the same elements as those in the conventional example shown in FIGS. 3 and 4 are given the same reference numerals, and redundant explanation thereof will be omitted.

The equipment for implementing the purification and recovery method according to this example is as follows:
For example, the main condenser 12, the condensate pump 13, the condensate filtration device 14, the condensate desalination device 15, and the condensate desalination device [15
The turbine system includes a spillover pipe 16 that transfers condensate from the tank to the condensate storage tank 8, and a water transfer pipe 17 that guides the water 4 to the suction side of the condensate pump 13.

In addition, a water handling pipe 5 for extracting the filled water 4 from the reactor well 2, the equipment temporary storage pool and the fuel pool 3, and the middle gate of the filled water transfer pipe 17 are provided with a fuel pool cooling purification system filter sharp salting device M7.
In addition, a bypass pipe 18 that bypasses the filtration and demineralization device 7 is provided.

When the periodic inspection work is completed, the water 4 stored in the reactor well 2, equipment temporary storage pool, and fuel boule 3 is pressurized by the fuel pool cooling and purification system pump 6 via the water drainage pipe 5, and the fuel pool is cooled and purified. It is supplied to the system filtration and desalination equipment 7, where it is purified. The purified fill water further passes through a fill water transfer pipe 17 and is sent to a turbine-based condensate pump 13.
is introduced into the suction side of the The introduced water is pressurized by the condensate pump 13 and is sequentially passed through the condensate filtration device 14 and the condensate desalination device 15 for purification.

The purified fill water passes through the spillover pipe 16 and is collected into the condensate storage tank 8.

Here, since both the condensate filtration device 14 and the condensate filtration device 15 have sufficient purification ability and processing capacity, the fuel pool cooling purification system filtration desalination device! Without using t7, the water is directly introduced into the suction side of the condensate pump 13 through the bypass pipe 18 and the water transfer pipe 17, and only the turbine-based condensate filtration device 14 and condensate desalination device 15 are used. It is also possible to carry out purification treatment.

In this way, according to this embodiment, the water is purified using the turbine-based condensate filtration device 14 and the condensate desalination device 15, which have a large purification capacity and processing capacity, so that the conventional purification and recovery method is not possible. Compared to the conventional method, it is possible to treat the filling water to a high degree in a short time, and the time for collecting the filling water can be significantly shortened.

Furthermore, since the waste treatment equipment is bypassed and the water is purified, the load on the waste treatment equipment, where wastewater is concentrated during periodic inspections, can be reduced.

Next, a further embodiment of the present invention will be described with reference to FIG. In this embodiment, the water 4 stored in the reactor well 2, the equipment temporary storage pool, and the fuel boule 3 is passed through the reactor coolant purification system piping 2o branched from the reactor recirculation system piping 19, and the coolant After being extracted by the purification system pump 21 and treated by the reactor coolant purification system filtration desalination device 22, the extracted fill water is introduced into the suction side of the condensate pump 13 through the fill water transfer pipe 17.

The introduced water is purified by passing through the turbine-based condensate filtering device 14 and the condensate desalination device M15, as in the above-described embodiment. The purified fill water is collected into the condensate storage tank 8 through a spoolover pipe 16 that branches at the outlet side of the device.

In addition, since the turbine system condensate filtration equipment @14.15 has sufficient purification ability and processing capacity, the water from the reactor coolant purification system piping 20 is passed through the bypass pipe 18 and further It is also possible to introduce the water directly into the suction side of the condensate pump 13 via the water transfer pipe 17 .

In this embodiment as well, it is possible to perform high-level treatment and rapid recovery of the filled water.

Note that it is also possible to directly use the purified water purified by the condensate filtration and desalination equipment as makeup water to the condensate system.

Although Figures 1 and 2 above show an example in which the fill water is extracted from the fuel pool cooling purification system piping or the reactor recirculation system piping, it is also possible to extract the fill water from the residual heat removal system piping. It is.

In any case, during periodic inspections, the inside of the reactor pressure vessel 1, the reactor well 2, the equipment temporary storage pool, and the fuel pool 3 are in good communication; therefore, the reactor recirculation system connected to the reactor pressure vessel 1, Filling water can be extracted by using either the residual heat removal system or the reactor coolant purification system.

As described above, as equipment for implementing the method of this embodiment, most of the existing piping systems and equipment can be used as they are, and there is an advantage that major modifications are not required.

(Effects of the Invention) As explained above, according to the method for purifying and recovering fill water for periodic inspections according to the present invention, fill water stored in the reactor well, the rudder temporary pool, and the fuel pool is removed from the turbine system. Introduced into the suction side of the condensate pump. The introduced water is pressurized by a condensate pump, highly purified by a turbine-based condensate filtration device and a condensate desalination device, and then collected into a condensate storage tank via spillover piping.

・Here, the processing capacity of turbine-based condensate filtration equipment and condensate desalination equipment is much larger than that of the filtration salt equipment of fuel pool cold section purification systems and the filtration desalination equipment of waste treatment systems. , the removal rate of contaminants is also high, so water can be filled up to 8 times in a short time.
This makes it possible to process the water at once, and also significantly shortens the time required to collect the water.

Furthermore, since the waste treatment equipment is bypassed and the water is purified, the load on the waste treatment system during periodic inspections can be reduced.

Condenser, 13... Condensate pump, 14... Condensate filtration device, 15... Condensate desalination device, 16... Spillover piping, 17... Filled water transfer pipe, 18... - Bypass pipe, 19... Reactor recirculation system piping, 20... Reactor coolant purification system piping, 21... Coolant purification system pump, 2
2... Reactor coolant purification system filtration and desalination equipment.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing an embodiment of the method for purifying and collecting water for periodic inspection according to the present invention, Fig. 2 is a system diagram showing an embodiment of the present invention, and Fig. 3 is a system diagram showing a conventional method for purifying and recovering water for periodic inspection. FIG. 4 is a system diagram showing a conventional purification and recovery system.

Claims (1)

[Claims] 1. In a method for purifying and recovering water for periodic inspections stored in a reactor well, equipment temporary pool, and fuel pool during periodic inspections of a nuclear power plant equipped with a turbine system, The water is introduced into the suction side of the condensate pump, and the introduced water is pressurized by the condensate pump and purified by passing it through the condensate filtration device and the condensate desalination device.The purified water is then passed through the spillover piping. A method for purifying and collecting water for regular inspections, which is characterized by collecting the water via the condensate storage tank. 2. The fill water is extracted from any of the piping systems of the fuel pool cooling and purification system, reactor recirculation system, residual heat removal system, and reactor coolant purification system, and introduced into the suction side of the condensate pump of the turbine system. 2. The method for purifying and recovering water for periodic inspection according to claim 1.