JPS5987393A - Device for controlling humidity in 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] [Field of Application of the Invention] The present invention relates to a humidity control device in a reactor containment vessel, which completely suppresses the movement of gas trapped in pressure suppression water into the reactor containment vessel. The present invention relates to a gas diffusion prevention device suitable for.

[Prior art]

A gas temperature control system within the reactor containment vessel will be explained with reference to FIG. In FIG. 1, the inside of a reactor containment vessel 61 is sealed with nitrogen gas during operation of the reactor to prevent an explosion due to hydrogen that would occur in the event of an accident. The temperature of the nitrogen gas is controlled by introducing the gas from the upper and middle layers of the reactor containment vessel 1 into the dry well cooler through the intake duct 3, cooling it, and then exhausting it through the exhaust duct 4. The temperature of the gas inside the reactor containment vessel 1 and the intake duct 3 is about 70C, and the temperature near the exhaust port where it is cooled by the cooler 2 and discharged is about 30C''C''. Cooling water is always flowing through the control rod drive water pipe that runs above the central exhaust port 5, so the pipe surface temperature is in the range of 10 to 40C, so it is cooled by the cooler 2 and the relative humidity increases. When the gas is blown onto the restraint rod drive piping, it may be further cooled and may form condensation. Furthermore, chlorine contained in the gas dissolves in water droplets generated on the surface of the pipe and causes condensation.

Locations where water droplets with a high chlorine concentration are present are where corrosion preferentially progresses and becomes a starting point for pipe rupture.

The most effective measure against pipe fractures caused by water droplets on the pipe surface is to lower the humidity inside the reactor containment vessel. Therefore, a new cooler 2
The salinity of the cooling water used in the system is lowered by using a refrigerator, and the cooler is equipped with a dehumidifying function.

However, since gas that has become highly humid due to evaporation of the pool water 8 in the pressure suppression chamber 7 constantly diffuses from the opening at the bottom of the reactor containment vessel 1, a problem arises in that sufficient humidity cannot be lowered.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a device that completely shields high-humidity gas in a pressure suppression chamber during operation of a nuclear reactor in order to completely control humidity in a reactor containment vessel.

[Summary of the invention]

The rupture of low-temperature piping inside the reactor containment vessel is due to water droplets forming on the piping surface due to low humidity in the containment vessel, and chlorides in the gas dissolving into the water droplets, accelerating corrosion.

Therefore, the relative weight of pipe rupture is the humidity inside the reactor containment vessel? We believe that it is effective to eliminate dew condensation and completely suppress the occurrence of corrosion by controlling the control at a low level.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG.

A second
Attach a tray lid to the opening as shown in Figure (1).

When the reactor containment vessel 1 is completely filled with nitrogen gas, this lid 10 must pass the nitrogen gas flowing into the reactor containment vessel 1 from the nitrogen gas filling port in the pressure suppression chamber through the opening 9. As shown in FIG. 2 (2), the lid 1O has an opening/closing device [11] that moves up and down.

In addition, the pressure suppression chamber pool water is stored to absorb all the gas generated during an accident and as make-up water in the event of a loss of reactor water accident. In particular, in order to absorb and eliminate the gas generated in the reactor containment vessel during the former accident, the following two
It has one or both of the following functions.

First, as shown in FIG. 2 (1), a membrane 12 is installed that can rupture at a pressure difference of 0.1 atmosphere between the pressure suppression chamber and the reactor containment vessel. For example, transport items such as glass and plastic that are difficult to deform due to heat.

Second, as shown in FIG.
There is a system in which a signal is sent by all cables 15 to open the lid 10 at 11 atmospheres or more.

7'c The lid 10 is opened and closed by W. As shown in FIG.
8 rotates to move the support column 19 up and down, and the lid 10
open and close. Opening when charging nitrogen gas at reactor startup and closing during operation are operated outside the reactor containment vessel, and it is automatically opened when the pressure difference between the pressure suppression chamber and the reactor containment vessel is 0.1 atmosphere or more. Control.

〔Effect of the invention〕

With the above system, it becomes easy to control the humidity inside the reactor containment vessel, and the dehumidifying refrigerator equipment can also be made smaller.

[Brief explanation of drawings]

Figure 1 is a diagram explaining the gas flow and gas temperature control in the reactor containment vessel, Figure 2 is a diagram explaining the structure and operation of the lid that shields high humidity gas in the pressure suppression chamber, and Figure 3 The figure illustrates a system that detects the pressure difference between the pressure suppression chamber and the inside of the reactor containment vessel and opens the lid. Figure 4 illustrates the operation of the pressure suppression chamber high-humidity gas cover. It is. DESCRIPTION OF SYMBOLS 1... Reactor containment vessel, 2... Cooler, 3... Intake duct, 4... Exhaust duct, 5... Exhaust port, 6...
... System-Il14I44! Drive water piping, 7... Pressure suppression chamber, 8... Pressure suppression chamber pool water, 9... Opening,
10... Pressure suppression chamber high humidity gas shielding lid, 11... Lid opening/closing device, 12... Pressure suppression chamber pressure gauge, 13...
Reactor containment vessel pressure gauge, 14...lid m+control device,
15... Lid control signal transmission cable, 16... Lid movement motor, 17... Gear, 18... Rotation 111 Figure 2 Rod 3 Mouth

Claims (1)

[Claims] 1. A humidity control device in a reactor containment vessel, characterized in that a lid is installed at a pressure suppression opening of the reactor containment vessel as part of a humidity control system in the reactor containment vessel. . 2. The humidity control device in a reactor containment vessel according to claim 1, which is characterized by having a device that can open and close an opening when replacing gas in the reactor containment vessel. 3. Scope of Permit Request In Clause 1, humidity control inside the reactor containment vessel is characterized by having a system that opens the lid when the pressure difference between the reactor containment vessel and the pressure suppression chamber is 0.1 atmosphere or more. Device. 4. Range of Permissible Waste Requirement In Item 1, the product is manufactured by a humidity controller in the reactor containment vessel characterized by having a membrane that ruptures when the pressure difference between the reactor containment vessel and the pressure suppression chamber is 0.1 atm or more. Place.