JPS63191097A - Nuclear reactor facility - 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 Industrial Application] The present invention relates to nuclear power generation equipment, and in particular, by supporting the reactor containment vessel, reactor pressure vessel, etc., which are important for earthquake resistance, on the reactor building foundation, This article relates to nuclear power generation equipment suitable for improving earthquake resistance.

[Conventional technology]

As an example of conventional technology, a reactor containment vessel of a boiling water nuclear power generation facility plant and a reactor pressure vessel included therein,
The configuration of the pressure vessel pedestal, etc. that supports the reactor pressure vessel will be explained below using FIG. 3.

In this prior art, a reactor pressure vessel 2 containing a nuclear reactor core 1 is arranged on a reactor building foundation that constitutes a strong structure with a pressure vessel pedestal 5.

In addition, a reactor containment vessel 3 is installed as a container surrounding the reactor pressure vessel 2 and also includes the above-mentioned main equipment. 10. The space filled with the lower suppression pool water 8 is divided into two parts called wet wells.

The dry well 10 and the wet well 11 are connected by a vent pipe 9, and the vent pipe 9 is connected to the suppression pool water 8 stored in the wet well 11.
The open end is submerged in water.

On the other hand, inside the dry well 10, the reactor pressure vessel 2
A gamma ray shielding wall 4 is installed as a cylindrical concrete structure on a pressure vessel pedestal 5 that supports the reactor pressure vessel 2, surrounding the reactor core 1, and functions to shield gamma rays from the reactor core 1. There is. Further, on the outside of the reactor containment vessel 3, an overall barrier wall 12 that is structurally integrated with the building is constructed, and the gamma ray barrier wall 4
The design takes into consideration the protection of the entire nuclear power generation facility from radiation exposure in order to avoid the Nojiyahei effect.

Furthermore, inside the dry well 10, main steam piping that supplies the coolant from the yK child reactor pressure vessel 2 to the turbine power generation equipment side, equipment piping that recirculates the coolant, etc. are arranged, but these are typical examples of large equipment. As shown in FIG. 3, there is a reactor recirculation pump 6, which is shown disposed at the bottom of the reactor pressure vessel.

The inside of the reactor containment vessel 3 has the main arrangement as described above, but in this conventional technology, the equipment arrangement inside the containment vessel is made as compact as possible, and the related equipment and structures installed inside or outside are simplified. This is considered to be effective in rationalizing the entire nuclear power plant, and the factors in the arrangement and configuration of equipment inside the reactor containment vessel in this prior art will be explained below.

The shape and capacity of the reactor containment vessel 3 containing the reactor pressure vessel 2 are determined based on the shape and capacity of the dry well 10. In other words, in the event that the reactor-subsystem piping installed in the reactor containment volume 1f13 ruptures, high-temperature, high-pressure reactor-subcoolant will be released into the dry well 10, and a mixture of released steam and water will be generated. is led to the suppression pool water 8 via the vent pipe 9, and has the function of suppressing the increase in internal pressure of the dry well 10 by cooling and condensing the released steam with the suppression pool water 8. Therefore, it is important to reduce the space volume of the dry well 10 as much as possible for this pressure suppression function.
This leads to a reduction in the space volume of the nuclear reactor containment vessel 3, which in turn leads to a reduction in the space volume of the reactor containment vessel 3 as a whole.

In this prior art, in relation to the above, the space shape is determined taking into account the space for piping inside the dry well 10, the installed valves, the arrangement of equipment, and the maintenance space. The installation position of the recirculation pump 6 is a major determining factor. This is based on the requirement to install the coolant recirculation pump 6 below the bottom level of the reactor pressure vessel 2 while ensuring the required water head of the pump for the recirculation function of the primary cooling water in the reactor pressure vessel 2. be. For this reason.

As a result, the height of the dry well is increased in addition to the above-mentioned factors that determine the space of the dry well 10. In order to solve this problem, for example, the coolant pump 6
It is conceivable to install it at the bottom of the reactor pressure vessel 2 or between the pressure vessel pedestal 5 and the wet well 11, but in this case, it is possible to install it at the bottom of the reactor pressure vessel 2. ! ! The control rod drive system of the equipment is installed at the bottom of the reactor pressure vessel 2,
In the latter case, an additional annular space for installing the coolant recirculation pump 6 would be provided in the outer peripheral area of the current pressure vessel pedestal 5, which would lead to an increase in the wet well space diameter. On the contrary, it is becoming a factor that increases the layout compared to the current technology.

In addition, as described above, reactor pressure vessel 2. Pressure vessel pedestal 5. As well as the relative positional relationship of the diaphragm floor 7 is determined, the reactor pressure vessel 2 is installed in the middle of the dry well 10, and for this reason.

In order to reduce exposure to radiation from the reactor core 1, a gamma ray blocking wall 4 is installed around the outer periphery of the reactor pressure vessel 2.
Furthermore, in order to protect the reactor building from exposure to radiation through the dry well 10 space, a biological barrier wall 1 is installed in the building outside the reactor containment vessel 3 in accordance with the requirements for protection.
The gamma ray shielding wall 4 is installed inside the dry well 10, so that the radial shape of the dry well 10 is determined by this equipment. Needless to say, this is a factor.

[Problem that the invention seeks to solve]

In the above-mentioned conventional technology, the space shape of the reactor containment vessel is made as compact as possible based on the factors that determine the arrangement and configuration of each equipment inside the reactor pressure vessel, but it is not possible to make it more compact than the current situation. The configuration makes it difficult to rationalize the blocking structures required for the layout of each facility.

The object of the present invention is to change the arrangement of equipment in the reactor containment vessel of the conventional nuclear power generation equipment described above so as to take advantage of the features of the 4m natural circulation boiling water reactor equipment, thereby improving the reactor containment space. The aim is to improve earthquake resistance by compacting the volume, eliminating the reactor pressure vessel pedestal, and directly supporting the reactor pressure vessel and gamma ray shielding wall on the reactor building foundation.

[Means for solving the problem] The above purpose is to arrange the reactor pressure vessel of the nuclear equipment in the lower dry well space formed in the center of the suppression pool, and to connect the reactor pressure vessel and the building to the building. This is achieved by a structure that can be directly supported by the foundation.

[Effect]

By providing means to solve the above-mentioned problems, it becomes possible to place a pressure vessel in the center of the suppression pool.
This shows a tendency to be able to support pressure vessels more directly on the building foundation, further promoting plant rationalization and improvement in seismic resistance.

〔Example〕

In the embodiments of the present invention, a specific target is a natural circulation boiling water type nuclear power generation facility. Unlike conventional boiling water nuclear power generation facilities, it is characterized by the absence of so-called reactor recirculation system equipment.

For this reason, the equipment configuration is such that recirculation piping for recirculating the sub-reactor coolant and coolant recirculation pumps associated with the above equipment are not installed.

Therefore, as explained in the prior art, when arranging equipment in the dry well in the reactor containment vessel, the location requirements are determined by the required water head limit of the recirculation pump in relation to the secondary coolant water level in the reactor pressure vessel. As a result, there is no equipment required to be installed at the bottom of the reactor pressure vessel except for the control rod drive mechanism, and a dry well protrusion space that is configured to form a cylindrical shape in the center of the conventional wet well is formed.
It becomes possible to move the installation level of the reactor pressure vessel to the lower part. At the same time, by arranging a gamma ray shielding wall that forms the boundary between the dry well and the Hora 1 Hewell around the circumference of the dry well protruding space, the reactor pressure vessel can be installed at a lower location. In combination, the following favorable rational arrangement of equipment inside and outside the reactor containment vessel and improvement in earthquake resistance can be obtained.

In other words, since most of the reactor pressure vessel is installed in the dry well protrusion space, the shape of the dry well upper space is determined only by the routing of the main steam piping and water supply piping, and maintenance requirements for their valves, etc. This makes it possible to significantly reduce the dry well space volume, and furthermore, this effect makes it possible to reduce the wet well space volume, whose capacity is determined to satisfy the pressure suppression effect. Achieving compactness of the overall volume of the container. In addition, as a synergistic effect, the upper end of the reactor core is set below the water level of the suppression pool in the surrounding wet well and the above-mentioned gamma ray blocking wall is constructed around the reactor core. Due to the water barrier effect, it has the effect of significantly reducing the thickness of gamma ray shield walls and biological barrier walls outside the reactor containment vessel compared to conventional methods.

Furthermore, by lowering the reactor pressure vessel, the conventional concrete pressure vessel pedestal support becomes unnecessary, and the reactor pressure vessel and gamma ray shielding wall can be directly supported by the reactor building foundation. It will have an effect.

Embodiments of the present invention based on the above principle of operation will be described in more detail below with reference to the drawings.

FIG. 1 shows the arrangement of the reactor pressure vessel, reactor containment vessel, and peripheral equipment of a natural circulation boiling water nuclear power generation facility according to the present invention.

In this figure, 2 is a reactor pressure vessel containing a nuclear reactor core 1 . A pressure vessel 2 is arranged in a space of a lower dry well 10a formed at the center of a wet well (suppression pool) 11 in the containment vessel 3 and connected to an upper dry well 10, and in particular, the upper end of the reactor core 1 is is arranged so as to be installed below the water level of the suppression pool water 8 in the wet well 11.

The space shape of the upper dry well 10 is designed to be minimized by taking into consideration the routing of main steam piping and water supply piping, and the ease of maintenance of valves, etc.
It consists of areas separated by a diaphragm floor 7.

Outside the space of the lower dry well loa in which the lower part of the reactor pressure vessel 2 is located, there is a gamma ray shielding wall 4 that partitions the dry wells 10, 10a and 8 parts of the suppression pool water in the wet well 11 inside. is installed, and the dry wells 10, 10a are installed together with the diaphragm floor 7.
It forms the boundary of the wet well 11, and has a structure that is directly supported by the reactor building basic structure.

In addition, the reactor pressure vessel 2 has a structure in which its bottom is supported by the reactor building basic structure via the pressure vessel skirt 13, and is of a so-called low center of gravity type in which the core position is extremely low due to the arrangement within the reactor building. This constitutes the reactor pressure vessel arrangement.

In this way, by lowering the position of the gamma ray shielding wall 4 and the reactor pressure vessel 2, the gamma ray shielding wall 4 and the reactor pressure vessel 2 are lowered.
4 and the reactor pressure vessel 2 can be reduced. FIG. 2(a) shows a floor response spectrum at the top of the pressure vessel pedestal 5 in the prior art. Also, Figure 2 (
b) shows the floor response spectrum at the upper end of the reactor building foundation, but compared to Fig. 2(a) above, the acceleration is approximately 172, and the seismic input will be reduced by half compared to conventional nuclear power generation facilities.

In the nuclear power generation equipment of the present invention configured in this manner, as described in the explanation of the principle of operation, the dry well space volume within the reactor containment vessel 3 is significantly reduced, and the wet well space is At the same time, the volume can be reduced, which is extremely effective in achieving a compact arrangement of the entire reactor containment vessel 3.
Most of the lower part of the reactor pressure vessel 2 is enclosed in the protruding space of the dry well 1o, so that the gamma ray blocking wall 4 of the peripheral cylindrical part is protected by the water blocking effect of the suppression pool water 8 existing in the peripheral area. , similar to the biological barrier wall 12 installed outside the reactor containment vessel 3, the wall thickness can be significantly reduced compared to the conventional one, and the lower installation of the reactor pressure vessel 2 makes it possible to reduce the wall thickness compared to the conventional one. Eliminating the need for a concrete pressure vessel pedestal support structure, lowering the center of gravity of the reactor core and reducing input seismic motion can significantly improve earthquake resistance. Compactness due to improved layout efficiency, elimination of related equipment structures, and reduction in damping effects. It is possible to achieve significant benefits such as cost reduction, improved constructability, and improved seismic safety by reducing the structure involved in the improvement.

〔Effect of the invention〕

According to the present invention, the volume of the containment vessel can be made more compact by facilitating the optimization of the equipment layout in the reactor containment vessel of nuclear reactor equipment, the removal of the reactor pressure vessel pedestal, and the thickness of the gamma ray blocking wall and the living body blocking wall. It is possible to provide suitable nuclear power facilities that have great effects on plant rationalization and cost reduction, such as reduction in the amount of energy used, as well as significant improvements in constructability by reducing the amount of equipment required, and improvements in seismic safety. Become.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view illustrating the implementation status of the arrangement of nuclear power generation equipment according to the present invention, Fig. 2(a) is a floor response spectrum diagram of the top of the pressure vessel pedestal in the prior art,
FIG. 3(b) is a floor response spectrum diagram of the upper end of the reactor building foundation, and FIG. 3 is a longitudinal sectional view illustrating the arrangement of a conventional nuclear power generation facility. 1゛°Reactor core, 2... Reactor pressure vessel, 3...
Reactor containment vessel, 4... Gamma ray shielding wall, 5°゛° pressure vessel pedestal, 6... Coolant recirculation pump,
7. Padiaphragm floor, 8. Suppression pool water, 9.
...Vent pipe, 10.Dry well, 11" wet well, 12. Biological barrier wall, 13-'° pressure vessel skirt.

Claims (1)

[Scope of Claims] 1. In a nuclear reactor containment vessel that includes a dry well in the upper part and a suppression pool in the lower part, a lower dry well space is provided in the center of the suppression pool part and is connected to the upper dry well, and A nuclear power facility, characterized in that a nuclear reactor pressure vessel is disposed across a dry well and the upper dry well, and the reactor containment vessel and the reactor pressure vessel are supported by a reactor building foundation. 2. In claim 1, a gamma ray shielding wall and a suppression pool installed outside the lower dry well in which the reactor pressure vessel is installed to separate the dry well and the suppression pool water in the wet well are defined as A nuclear power facility characterized by an arrangement in which it is supported by a building foundation.