JPH02126190A - Device for cooling atmosphere in reactor container - Google Patents

Abstract

PURPOSE:To uniformize the temperature inside a reactor container and at the same time, to suppress the relative humidity inside a pedestal to a low level by providing a supplying means which supplies non-cooled air into the pedestal provided to the bottom section of the container. CONSTITUTION:The air directly supplied from an air blower 6 is cooled by means of a cooler 5 and fed to the upper section of a pressure vessel 2 through a duct 11 for feeding air to the upper area. At the same time, the air is also fed into a bulk head 13 through another duct 12 for feeding air into the bulk head. Then the air descends through drywells while cooling the upper section of the pressure vessel 2 generating a large quantity of heat and returns to the vicinity of the blower 6. the air supplied to a duct 8 for feeding air to a gamma shield area flows upward along the vessel 2 while cooling the heat insulating material of the vessel 2 and descends to the lower sections of the drywells after the air is mixed with the air supplied from the duct 11 through the upper end of a gamma shield wall 2. Therefore, the temperature inside the drywells can be uniformized and at the same time, the relative humidity in a CRD area can be reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a reactor containment vessel atmosphere cooling device, and particularly to a reactor containment vessel atmosphere cooling device suitable for equalizing the temperature in a dry well. Regarding.

[Conventional technology]

Conventionally, the cooling system for cooling the inside of the reactor containment vessel is
An upper cooler and a lower cooler are provided at the upper and lower parts of the containment vessel, respectively, and air cooled by the upper cooler is supplied to the upper part of the containment vessel, while air cooled by the lower cooler is supplied to the lower part of the containment vessel (e.g. Air was being supplied to the gamma shield area and inside the pedestal.

However, with a cooling device configured like this.

Low-temperature areas were likely to occur within the pedestal below the reactor pressure vessel. In other words, the lower part of the pressure vessel has a small calorific value;
Also, since the warm air moves towards -L, the temperature inside the pedestal becomes lower than the rest, and as a result,
There was a problem in that the relative humidity inside the pedestal became high and the CRD piping arranged inside the pedestal became susceptible to corrosion.

Generally, CRD piping is made of stainless steel, but trace amounts of salt are often present in the pedestal, and even stainless steel still has the problem of corrosion resistance.

Therefore, in order to raise the temperature inside the pedestal, a cooling system has been proposed in which a ventilation hole is provided in the pedestal, and warm air from the upper part of the containment vessel is introduced into the pedestal through this ventilation hole, thereby lowering the relative humidity inside the pedestal. (Japanese Unexamined Patent Publication No. 100694/1983).

[Problem to be solved by the invention]

However, with the above-mentioned conventional technology, warm air must be constantly flowed over a long distance from the top of the containment vessel to the ventilation opening, so the temperature of the warm air may drop on the way, making it difficult to control the temperature inside the pedestal. The problem was that it was extremely difficult.

SUMMARY OF THE INVENTION An object of the present invention is to provide an atmosphere cooling system within a nuclear reactor containment vessel that can uniformize the temperature within a dry well and easily control the temperature.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an atmosphere cooling device for a reactor containment vessel in which air cooled by a cooler is circulated within the reactor containment vessel by a blower to cool the atmosphere inside the reactor containment vessel. A supply means is provided for supplying uncooled air into the pedestal below the reactor pressure vessel.

[Effect]

According to the above configuration, air cooled by the cooler is supplied to the upper part of the reactor containment vessel, and uncooled air is supplied to the pedestal below the reactor pressure vessel. Result 1
The J- section of the reactor pressure vessel, which generates a large amount of heat, is sufficiently cooled with cooling air, and there is no longer a low-temperature area inside the pedestal, which prevents the relative humidity inside the pedestal from increasing. .

〔Example〕

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

FIG. 1 shows the overall configuration of the cooling device of the present invention. As shown in the figure, a reactor pressure vessel (hereinafter referred to as a pressure vessel) is located inside a reactor containment vessel (hereinafter referred to as a containment vessel) 1.
2 is stored. The outside of the pressure vessel 2 is surrounded by a gamma shield U3, and the gamma shield wall 3 and the pressure vessel 2 are supported by a pedestal 4 from below.

Furthermore, a cooling coil 5 is provided on the outside of the gamma shield wall 3.
A cooler 5 having a diameter A is provided, and a blower 6 is provided below the cooler 5. The blower 6 and the cooler 5 are connected by a blower duct 7, and the blower duct 7 is connected to a gamma shield area air supply duct 8 and a CRD area air supply duct 1-.
9 is connected. The gamma shield area air supply duct 1-8 penetrates the gamma shield wall 3 and reaches the outer surface of the pressure vessel 2, and the CRD area air supply duct 9 penetrates the pedestal 4 and reaches the CRD area (inside the pedestal). 1
It has reached 0. Note that a lower area air supply port 9A is provided in the middle of the CRD area air supply duct 9.

Further, an upper area air supply duct 1 is connected to the cooler 5, and its tip reaches the upper part of the pressure vessel 2. Further”
An in-bulkhead air supply duct 12 is connected to the two-part area air supply duct 11, and its tip reaches inside the bulkhead 13.

Note that the blower 6, the blower duct 7, and the CRD area air supply duct 9 constitute a supply means.

The operation of this embodiment will be briefly explained.

The air directly sucked in from the blower 6 is cooled by the cooler 5, and is supplied to the upper part of the pressure vessel 2 via the upper area air supply duct 11, and also to the bulkhead via the bulkhead air supply duct 12. Air is supplied into 13. Then, while removing heat from the upper part of the pressure vessel 2, which has a large calorific value, it descends inside the dry well and returns to the vicinity of the blower 6. On the other hand, the uncooled air that branches off from the ventilation duct 7 midway is sent to the gamma shield area air supply duct 8 and the CRD area air supply duct 9.6 The air sent to the gamma shield area air supply duct 8 has a pressure It flows upward along the pressure vessel 2 while removing the heat generated by the heat insulating material in the vessel 2, passes through the upper end of the gamma shield wall 2, and is mixed with the air supplied from the upper area air supply duct 11 to the lower part of the dry well. Descend to the department. Also, part of the air sent to the CRD area air supply duct 9 is supplied to the lower part of the containment vessel 1 through the lower area air supply port 9A, and the rest is supplied to the CRD area]0
Air is supplied inside. The air supplied into the CRD area]-0 is exhausted to the lower area through the ventilation port 14.

As described above, by supplying cooled air to the upper part of the dry well, where the temperature tends to rise, and uncooled air to the middle and lower parts, the temperature inside the dry well can be made uniform. At the same time, it becomes possible to reduce the relative humidity in the CHD area 10, and it is possible to maintain the environmental conditions of the stainless steel material in a favorable state.

Further, according to this embodiment, by supplying uncooled air into the gamma shield wall 3, the amount of heat removed from the lower part of the pressure vessel 2 can be reduced.

Further, according to this embodiment, the blower 6 is installed at the lower part of the containment vessel 1, and the lower area air supply port 9A is provided near the blower 6, so that a circulation flow of air is formed in the lower area. Therefore, a method can be adopted in which air is directly sucked into the blower 6, and a return duct or the like can be eliminated.

2 and 3 show other embodiments of the invention. Note that the same parts as in the above-described embodiment are denoted by the same reference numerals.

In FIG. 2, the blower 6, cooler 5, upper area air supply duct 11, etc. are the same as those in the above-described embodiment. A gamma shield area exhaust duct 21 that reaches the CRD area 1o and a CRD area exhaust duct 22 that penetrates the pedestal 4 and reaches the CRD area 1o are provided, and these gamma shield area exhaust duct 21 and CRD area exhaust duct 22 are connected to a blower. It is connected to the suction side of No.6.

With this configuration, when the air in the CRD area 10 and the gamma shield area is sucked by the blower 6, the air in the lower area is supplied to the CRD area 10 and the gamma shield area through the ventilation opening 4.

That is, uncooled air is supplied to the CRD area 10 and the gamma shield area.

FIG. 3 shows an example in which the blower is divided into an upper blower 6a and a lower blower 6b. In the figure, the upper blower 6a, cooler 5, upper area air supply duct 11, etc. are the same as in the embodiment shown in FIG. In this embodiment, 31 to the gamma shield air supply duct 1 communicating with the f-en shield area.
and a CRD air supply duct 3 communicating with the CRD area 10.
2 is connected to the discharge side of the blower 6b. Further, the sum of the air volume of the upper blower 6a and the air volume of the lower air blower 6b is set to correspond to the air volume of the air blower 6 shown in FIG.

In this embodiment as well, CRD area 1o and gamma
Uncooled air will be supplied to the shield area.

〔Effect of the invention〕

As explained above, according to the present invention, the temperature inside the reactor containment vessel can be made uniform, and the relative humidity inside the pedestal can be kept low, thereby maintaining a favorable environment for rustless steel materials. becomes possible.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention, and FIGS. 2 and 3 are overall configuration diagrams showing other embodiments, respectively. 1... Reactor containment vessel, 2... Reactor pressure vessel. 3... Gamma shield wall, 4... Pedestal, 5
...Cooler, 6, 6a, 6b...Blower, 8.31
... Gamma shield area air supply duct, 9.32.
...CRD area air supply duct, 14...Ventilation vent. 21... Gamma shield area exhaust duct, 22.
・CRD area exhaust duct.

Claims (1)

[Scope of Claims] 1. In a reactor containment vessel atmosphere cooling system that cools the atmosphere within the reactor containment vessel by circulating air cooled by a cooler within the reactor containment vessel using a blower, 1. A reactor containment vessel atmosphere cooling system comprising a supply means for supplying uncooled air into a pedestal below a pressure vessel. 2. In the cooling device according to claim 1, the supply means is configured by providing an air supply duct that communicates with the inside of the pedestal in the middle of a blower duct that connects the discharge side of the blower and the cooler. A reactor containment vessel atmosphere cooling device characterized by: 3. The cooling device according to claim 1, wherein the supply means is configured by providing an exhaust duct between the suction side of the blower and the inside of the pedestal. . 4. The cooling device according to claim 1, wherein the supply means is configured by providing an air supply duct between the discharge side of the blower and the inside of the pedestal. Device. 5. The cooling device according to claim 1, 2, 3 or 4,
An atmosphere cooling system in a reactor containment vessel, characterized in that the supply means includes a duct for supplying uncooled air also to an area within the wall of the gamma shield.