JPS58151586A - Reactor container - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to improvements in nuclear reactor containment vessels.

If the pool water stored in the suppression chamber of the reactor containment vessel remains contaminated, the following problems will occur.

(1) It accelerates deterioration inside the suppression chamber, shortens the life of the plant, and requires enormous costs for painting and repair.

(2) There is a risk that the radiation dose rate around the pedestal that supports the reactor pressure vessel will increase, and the radiation dose for inspection workers will increase.

(3) Since pool water in the suppression chamber is used as core souffle water, in the event of a rupture accident in the secondary system, contaminated water will be injected into the pressure vessel, which is undesirable from the standpoint of equipment life. .

In consideration of the above problems, various methods have been proposed for purifying pool water in a suppression chamber.

The present invention purifies pool water stored in a suppression chamber more effectively than before, and its purpose is to:
Sludge that accumulates at the bottom of the subrection chamber,
The present invention aims to provide an improved nuclear reactor containment vessel that can minimize pollution of pool water by easily collecting and treating deposits such as dust.

The present invention provides a reactor containment vessel with a structure in which a dry well and a subrepression chamber are divided into upper and lower sections through a diaphragm floor, and a chamber that forcibly stirs the entire bottom of the suppression chamber that stores pool water. a bottom agitation means; It is characterized by comprising a groove, a drainage channel communicating with the sediment accumulation groove, and a waste treatment means for accumulating and concentrating and disposing of the sediment in the chamber that has been led to the drainage channel. It is something to do.

Hereinafter, the present invention will be explained based on an embodiment of the drawings. FIG. 1 is a longitudinal cross-sectional view of a subreduction chain and its peripheral equipment, and FIG. 2 is a cross-sectional view of FIG. 1. A pressure vessel 3 is installed on a pedestal 2 within a reactor containment vessel l. The containment vessel 1 is divided into a dry well 5 and a suppression chamber 6 via a diaphragm floor 4, and the suppression chamber 7) includes:
Pool water 7 is stored. 8 is a pressure pump installed on the pedestal 2; 9 is a water supply pipe whose one end is connected to the pressure pump 8; the other end of the water supply pipe 9 is connected to an annular pipe 10 surrounding the base of the pedestal 2; In the annular tube 10,
A plurality of jet nozzles 11 are attached. 1
Reference numeral 2 denotes a deposit accumulation groove provided at the bottom of the suppression chamber 6, and the groove 12 is sloped in a downward direction toward the outside of the containment vessel 1. Reference numeral 13 indicates a drainage channel communicating with the groove 12, 14 indicates a sediment storage tank, and a gate valve 15 is provided between the drainage channel 13 and the tank 14. 16 is a drainage pump attached to the tank 14; 17 is a drainage pipe whose one end is connected to the pump 16;
It is coming within.

In the above configuration, if the atomic coupler has been operated for a long time and deposits A such as sludge and dust have accumulated at the bottom of the suppression chamber 6 that stores the pool water 7, check the timing accordingly. The pressurizing pump 8 is driven. When the pump 8 is driven, the pool water in the suppression chamber 6 is supplied to the annular pipe 10 via the water supply pipe 9, and is jetted out from the jet nozzle 11 as high pressure water. When high-pressure water is ejected from the jet nozzle 11, the sediment A accumulated at the bottom of the suppression chamber 6 is stirred and gradually falls into the sediment accumulation groove 12. The sediment A that has fallen into the groove 12 is blown away by the force of the high-pressure water jetted from the jet nozzle 11.
It is guided to the drainage channel 13 along the slope of the groove 12. Here, when the gate valve 15 is suddenly opened, the deposit A in the drainage channel 13 is accommodated in the deposit storage tank 14. Gate valve 1
5 is closed, the supernatant liquid in the tank 14 is sent to the drain pipe 17 via the drain pump 16, and returned from the drain pipe 17 into the suppression chamber 6 as pool water 7, and thereafter the above cycle is repeated. The deposits accumulated in the tank 14 may be treated as concentrated waste.

Therefore, according to the present invention having the above configuration, not only can the sediment at the bottom of the containment vessel be collected and treated with a small number of personnel, but also the contamination of the pool water can be minimized. This helps to prevent deterioration of various equipment and equipment that come in contact with it as much as possible, thereby extending the lifespan of the plant. Furthermore, minimizing the pollution of the pool water also minimizes the radiation dose rate around the pedestal, contributing to reducing radiation exposure for inspection workers.

As described in detail above, according to the present invention, deposits such as sludge and dust that accumulate at the bottom of the suppression chamber of the reactor containment vessel are removed even though they are located below the water surface in the center of the reactor building. By easily collecting and treating these deposits, it is possible to provide an improved reactor containment vessel that can minimize contamination of pool water.

[Brief explanation of drawings]

The drawings show an embodiment of the reactor containment vessel according to the present invention,
FIG. 1 is a longitudinal cross-sectional view of the subrection/chamber sono peripheral equipment, and FIG. 2 is a cross-sectional view of FIG. 1. ■...Reactor containment vessel, 2...Pedestal, 3...
・Reactor pressure vessel, 4... diaphragm floor, 5.
...Drywell, 6...Suppression Che/Formula,
7... Pool water, 8... Pressure pump, 9... Water supply pipe, 10... Annular pipe, 11... Jet nozzle, 12
...Sediment accumulation groove, 13...Drain channel, 14...Sediment storage tank, 15...Gate valve, 16...Drain pump, 17...Drain pipe, (1 other person) 1 m No. 211n

Claims (1)

[Claims] 1. In a nuclear reactor containment vessel having a structure in which a dry well and a suppression chamber are divided into upper and lower sections via a diaphragm floor, a chamber bottom stirring means for forcibly stirring the bottom of the suppression chamber storing pool water; A sediment accumulation groove provided at the bottom of the chamber, which accumulates the sediment stirred in the suppression chamber and has a slope gradually descending toward the outside of the containment vessel, communicates with the sediment accumulation groove. 1. A nuclear reactor containment vessel, comprising: a drainage channel; and a waste treatment means for accumulating and concentrating and disposing of deposits in the chamber that have been led to the drainage channel.