JPH07218677A - Nuclear reactor facility - Google Patents

Abstract

PURPOSE:To reduce the thickness of a secondary shield concrete wall by lowering the placement of equipment in a reactor containment and shortening the height of it and a reactor building. CONSTITUTION:A steel reactor containment 31 is installed on a concrete foundation 20. A suppression chamber 40 is formed by the space surrounded by the inner surfaces of a concrete structure 41, an upper concrete structure 42 and a head 43, the outer surface of the reactor containment 31 and the upper surface of the concrete foundation 20.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to nuclear reactor facilities for nuclear power plants.

[0002]

2. Description of the Related Art A nuclear power plant has a reactor containment vessel inside the reactor building, and the reactor containment vessel stores the reactor pressure vessel, the piping and equipment of the reactor system, and the loss of the reactor coolant. Secure safety even if it occurs. FIG. 2 is a sectional view showing the structure of a conventional containment vessel for a boiling water reactor (BWR).

The reactor containment vessel 1 is made of steel and is provided on a concrete foundation 20, a cylindrical lower part is provided with a conical upper part, and a top part is provided with a removable upper lid 2. Further, the liner plate 3 is stretched on the concrete foundation 20 to form a bottom portion. A reinforced concrete wall 21 is provided along the outer periphery of the reactor containment vessel 1, and the conical reinforced concrete wall serves as a secondary shielding wall 22. A reinforced concrete lid 23 is provided on the top.

Inside the reactor containment vessel 1, a cylindrical pedestal 4 is provided at the center of the bottom, and a reactor pressure vessel 5 is provided.
And supports a cylindrical living body shield wall 6 that shields radiation from the reactor pressure vessel 5. A diaphragm floor 7 is provided above the pedestal 4, and the reactor containment vessel is divided into upper and lower parts. The upper part is a dry well 8 and the lower part is a suppression chamber 9. The suppression chamber 9 is filled with water 10. A large number of vent pipes 11 are provided on the diaphragm floor 9 so that vapor generated when the cooling water is lost in the dry well 8 is introduced into the water in the suppression chamber 9 and condensed to prevent pressure rise and temperature rise.

[0005]

Since the suppression chamber 9 is provided below the reactor containment vessel 1 and the dry well 8 is provided above it, the height of the reactor containment vessel 1 becomes high, and The reactor building that houses the reactor containment vessel 1 is becoming larger. Further, even in the reactor containment vessel, the reactor pressure vessel 5, equipment and pipes related thereto, and the biological shielding wall 6 are arranged at a high position, so that the seismic load becomes large and the support structure becomes large.

The present invention has been made in view of the above problems, and by changing the arrangement of the suppression chamber, the height of the reactor containment vessel is lowered, the reactor building is lowered, and the seismic load is reduced. An object of the present invention is to provide a reactor containment vessel that reduces the number of secondary shielding walls made of concrete and reduces the number of secondary shielding walls.

[0007]

To achieve the above object, a reactor containment vessel provided on a concrete foundation, an inner surface of a reinforced concrete structure enclosing the reactor containment vessel, an outer surface of the reactor containment vessel, and concrete. And a suppression chamber consisting of a space surrounded by the upper surface of the foundation.

[0008]

The suppression chamber wraps the reactor containment vessel and is composed of a space surrounded by the inner surface of the reinforced concrete structure provided outside, the outer surface of the reactor containment vessel, and the upper surface of the concrete foundation. Therefore, unlike the conventional case, since it is not provided in the lower part of the dry well, the height of the reactor containment vessel is lowered, and the reactor building accommodating this can be lowered. Further, since the reactor pressure vessel in the reactor containment vessel, the equipment and pipes related thereto, and the position of the primary shielding wall are also lowered, the seismic load is reduced, and the supporting structure and the like are downsized. In addition, the suppression chamber is filled with water up to almost the same position as the living body shielding wall, and the radiation is attenuated by this water, whereby the thickness of the secondary shielding wall can be reduced. By setting the water thickness to be the same as the shielding ability of the secondary shield, it is possible to eliminate a considerable part of the secondary shield wall. Further, since the water is stretched around the reactor containment vessel, the water serves as a buffer material, and it becomes difficult for an external load such as seismic force to be transmitted from the reactor building to the reactor containment vessel. Further, even if the coolant is lost and steam is generated in the reactor containment vessel to raise the temperature, the water contained in the suppression chamber naturally cools the containment vessel.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the structure of the embodiment.
The reactor containment vessel 31 is made of steel, and the concrete foundation 2
0, and the lower end is fixed by an anchor 34 embedded in the concrete foundation 20. The reactor containment vessel 31 has a cylindrical lower portion and a detachable upper lid 32 on the upper end.
Is provided. A liner plate 33 is stretched inside the reactor containment vessel 31 on the concrete foundation 20 to form a bottom surface. An inverted L-shaped vent pipe 35 is attached to the upper end of the cylinder of the reactor containment vessel 31, and its tip extends to a predetermined position below the water surface in a suppression chamber 40 described later. Further, a vacuum break valve 36 is provided in the spherical shell portion above the position where the vent pipe 35 is attached, and when the pressure inside the reactor containment vessel becomes a negative pressure with respect to the suppression chamber 40 at the time of loss of the reactor coolant, Balance the pressure.

A pedestal 37 is provided on the concrete foundation 20 at the center of the reactor containment vessel 31, and supports the reactor pressure vessel 5 and the biological shielding wall 6. The pedestal 37 has a steel double cylinder filled with reinforced concrete, and the lower part of the double cylinder is connected to the liner plate 33.

A cylindrical concrete structure 4 having a space on the outer periphery of the reactor containment vessel 31 and extending from the concrete foundation 20 to the height of the upper lid 32 of the reactor containment vessel 31.
1 is composed of reinforced concrete. A cylindrical upper concrete structure 42 having a diameter smaller than that of the upper lid 32 but having an inner diameter larger than the diameter of the upper lid 32 is integrally formed of reinforced concrete, and the upper concrete structure 42 is A reinforced concrete lid 43 for closing the inner diameter of the cylinder is detachably provided. The outer surface of the reactor containment vessel 31, the concrete foundation 20
The space formed by the upper surface of the above, the inner surfaces of the concrete structure 41 and the upper concrete structure 42, and the lower surface of the lid 43 constitutes the suppression chamber 40.

A liner plate 44 is stretched over the upper surface of the concrete foundation 20 constituting the suppression chamber 40, the inner surfaces of the concrete structure 41 and the upper concrete structure 42, and the lower surface and outer periphery of the lid 43.

Although water is stored in the suppression chamber 40, its water level is set to a level slightly higher than that of the top of the living body shielding wall 6, and this water is used to shield the radiation so that the secondary shielding conventionally made of reinforced concrete is performed. The thickness of the wall 22 is reduced. When the distance between the reactor containment vessel 31 and the concrete structure 41 is sufficiently large, the effect of attenuating the radiation is great, so that the secondary shield wall 22 can be eliminated over a considerable range.

Further, due to the water stored, the reactor containment vessel 31 is cooled even if the temperature inside the reactor containment vessel rises due to the steam generated when the reactor coolant is lost, so that the internal temperature rise does not occur. Can be kept low. Furthermore, since this water acts as a buffer to reduce the seismic force applied from the reactor building, the reactor containment vessel itself, the reactor pressure vessel 5 in the reactor containment vessel, the equipment and pipes associated therewith, and the biological shielding wall. The seismic structure of 6 is simplified.

Further, since the height of the pedestal 37 is significantly reduced as compared with the conventional one, the height of the reactor containment vessel 31 is also significantly reduced, and along with this, the height of the reactor building that houses the reactor containment vessel 31. Will also be lower. As a result, the seismic load is also reduced, so combined with the above-mentioned water buffering effect,
Reactor containment vessel 31 and equipment provided therein,
The seismic structure of piping and structures will be simplified, and the seismic structure of the reactor building will also be simplified.

The inner surface shapes of the concrete structure 41 and the upper concrete structure 42 are cylindrical, but they may be polygonal. The outer shape of these concrete structures may be determined according to the requirements of the building.

[0017]

As is apparent from the above description, the present invention has the following effects by providing the suppression chamber so as to enclose the reactor containment vessel. Since the installation height of the equipment inside the reactor containment vessel can be lowered, the height of the reactor containment vessel becomes lower, and along with this, the height of the reactor building that houses the reactor containment vessel can also be made lower. it can. As a result, the seismic load of the reactor containment vessel, the equipment therein, and the reactor building that houses the reactor containment vessel is reduced, and the seismic structure is simplified. Since the radiation is shielded by the water stored in the suppression chamber, the thickness of the secondary shield wall can be reduced, and it can be unnecessary in some places. Even if steam and pressure rise in the reactor containment vessel due to loss of reactor coolant, etc., the pressure and temperature rise little because it is cooled by the water in the suppression chamber. The water in the suppression chamber acts as a cushioning material, making it difficult for the seismic load from the reactor building to be transmitted to the reactor containment vessel, thus improving the seismic performance of the reactor containment vessel and its internal equipment.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a nuclear reactor facility of the present invention.

FIG. 2 is a cross-sectional view of a conventional reactor containment vessel.

[Explanation of symbols]

5 Reactor Pressure Vessel 6 Living Shield Wall 20 Concrete Foundation 31 Reactor Containment Vessel 32 Upper Lid 33,44 Liner Plate 34 Anchor 35 Vent Pipe 36 Vacuum Break Valve 37 Pedestal 40 Suppression Chamber 41 Concrete Structure (Reinforced Concrete Structure) 42 Top Concrete Structure (Reinforced concrete structure) 43 Lid (Reinforced concrete structure)

Claims (1)

[Claims] 1. A suppression chamber comprising a reactor containment vessel provided on a concrete foundation, an inner surface of a reinforced concrete structure enclosing the reactor containment vessel, an outer surface of the reactor containment vessel and a space surrounded by an upper surface of the concrete foundation. And a nuclear reactor facility characterized by