JPS63120299A - Nuclear power plant - 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] [Object of the Invention] (Field of Industrial Application) The present invention is directed to an emergency gas treatment system (Standby GasT
Reactment system), especially the emergency gas treatment system piping (hereinafter referred to as
5GTS piping) etc.

(Prior Art) Generally, a nuclear power plant is provided with an emergency gas treatment system (hereinafter referred to as a 5GTS system) along with ventilation and air conditioning systems that ventilate and air condition the reactor building and the turbine building, respectively.

The 5GTS system replaces the reactor building ventilation and air conditioning system that is normally operated, and is automatically activated in an emergency to maintain negative pressure inside the reactor building and prevent radioactive materials leaking from the reactor containment vessel from spreading to the surrounding area. At the same time, radioactive substances are removed using a high-performance filter.

Figure 2 is a schematic diagram without showing a conventional nuclear power plant. The extending end of the 5GTS pipe 2 is formed into an exhaust port end 2a having an exhaust port. This exhaust port end 2a is housed in the main exhaust pipe 3 and stands upright, and is erected at approximately the same height as the main exhaust pipe 3.

The main exhaust stack 3 is connected to the exhaust duct l- of each ventilation air conditioning system (not shown) of the reactor building 1 and the turbine building 5 through a main exhaust duct 4 having a relatively large diameter. The air inside the turbine building 5 is released to the outside air.

Since the main exhaust stack 3 is a regular system like the main exhaust duct 4 and the turbine building 5, it is at the same seismic resistance level B as these.

On the other hand, since the 5GTS system is an emergency system, it has an earthquake resistance level of A.
Those belonging to seismic resistance level 8 are required to be supported by bedrock 6.

Therefore, the route section 2b1 of the 5GTS pipe 2 is routed endlessly until it exits from the reactor building 1 and is accommodated in the main exhaust stack 3. tS GTS pipe 1 - It is housed and protected within the wrench 7, and furthermore, this 5GTS pipe trench 7 is supported by the bedrock 6 via the artificial rock 8.

Note that the reactor building 1 and the turbine building 5 are directly supported and erected on the bedrock 6 because of their high seismic importance.

(Problems to be Solved by the Invention) However, in such a conventional nuclear power plant, although the main exhaust stack 3 itself is of seismic class B, the 5GTS piping exhaust port end 2a of seismic class A is included inside it. Therefore, there is a problem that it has to be launched as earthquake resistance class 8.

In other words, since the main exhaust stack 3 includes the 5GTS piping exhaust port end 2a, it is erected on the leveled surface 9 as earthquake resistance class A, and its total height (△ is the height permissible for nuclear plant safety evaluation). is set to

Therefore, the outer periphery of the main exhaust stack 3 is supported over almost the entire length by a support structure 10 such as a steel tower, and this support structure 10 is supported on the bedrock 6 via a plurality of foundations 11 and resistors 12. .

Therefore, there is a problem in that a huge amount of material is required to set up the main exhaust pipe 3 and the 5GTS pipe exhaust port end 2a, resulting in high costs.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a nuclear power plant that can significantly reduce the number of support structures used to raise the ends of the main exhaust stack and 5GTS piping exhaust.

[Structure of the invention]

(Means for Solving the Problems) The present invention solves the problems of conventional nuclear power plants in 5GTS.
Since the piping exhaust port end 2a is housed in the main exhaust stack 3 and raised together, it is required that the main exhaust stack 3, which originally has an earthquake resistance class of B, be designed to have an earthquake resistance class of A using 5GTS piping. It was created in consideration of the following points, and is structured as follows.

During normal times, moss grows in the main exhaust stack that discharges air purified by each ventilation air conditioning system in the reactor building J3 and turbine building to the outside air, and in an emergency, it automatically starts up in the reactor building ventilation air conditioning system, U In a nuclear power plant that has an emergency gas treatment system that purifies indoor air and then discharges it to the outside air through piping, the exhaust port end of the emergency gas treatment system piping is configured as an exhaust stack, and the exhaust stack is It was erected at the top of the reactor building mentioned above.

(Function) The present invention configures the exhaust port end of the emergency gas 9B science piping into an exhaust stack, and furthermore, this exhaust stack is installed on the reactor building with the same seismic resistance level as the emergency gas treatment system piping. do.

Therefore, the exhaust stack of the emergency gas treatment system piping is supported by the rock that directly supports the reactor building, and there is no need to prepare a separate rock for raising the exhaust stack.
Accordingly, the number of support structures can be significantly reduced.

(Example) Hereinafter, an example of a nuclear power plant according to the present invention will be described with reference to FIG.

FIG. 1 shows the overall configuration of an embodiment of the present invention. In the figure, a reactor building 20 is directly supported by a bedrock 21,
A nuclear reactor and 5GTS (not shown) are installed on the graded surface 22.
It has a built-in system.

The 5GTS system replaces the normal reactor building ventilation and air conditioning system (not shown) and is automatically activated in an emergency to maintain negative pressure inside the reactor building 20 and remove radioactive materials leaked from the reactor containment vessel (not shown). After preventing radioactive materials from dispersing to the surrounding area and at the same time removing radioactive materials using high-performance filters,
It is configured to be released to the outside air through GTS piping.

An exhaust port that opens to the outside air is formed at one end of the 5GTS pipe, and the end portion of the exhaust port having this exhaust port is configured as an exhaust pipe 23 and is erected on the upper part of the reactor building 20. The outer periphery of the exhaust pipe 23 is supported by a support structure 24 such as a steel tower erected on the outer periphery, and stands upright.
The air inside the reactor building 20 is exhausted to the outside air.

Therefore, the exhaust stack 23 is supported by the rock 21 that directly supports the reactor building 20, and there is no need to directly support the exhaust stack 23 by the rock 21.
3. It is possible to reduce the start-up costs.

On the other hand, the turbine building 25 houses a turbine (not shown) and is directly supported by the rock 21. At the top of the turbine building 25, a main exhaust pipe 26 is supported by a support structure 27 such as a steel tower and stands on a leveled surface 22. This main exhaust pipe 26
has a height of ground clearance HA.

The lower end of the main exhaust stack 26 is connected via a main exhaust duct 28 to each ventilation air conditioning system built in the reactor building 20 and the turbine building 25, respectively, and is purified by each ventilation air conditioning system etc. The air inside the reactor building 20J5 and the turbine building 25 is discharged from the main exhaust stack 26 to the outside air.

1 The height of the exhaust stack 26 is set to aHA above the ground,
Since it is erected at the upper part of the turbine building 25 which has a ground clearance of 1-IC, the total height of the main exhaust stack 26 itself is set to the height H8, which is the ground clearance 1-(Ce subtracted from the ground clearance HA). .

Therefore, the total height of the main exhaust stack 26 itself can be lowered by the ground height H0 than the main exhaust stack 3 of the conventional example shown in FIG.
The number of support structures 27 that support the can be reduced, and as a result, the number of construction steps can also be reduced.

Moreover, since the main exhaust stack 26 is erected on top of the turbine building 25 which is directly supported by the rock 21, it is possible to expect a reduction in the strength required for the main exhaust stack 26 and the support structure 27. Since the conventional main exhaust stack 3 (see FIG. 2) is supported by the rock 6, the foundation 11 and piles 12 required can be reduced.

Furthermore, in this embodiment, the exhaust stack 23 of the 5GTS system was separated from the main exhaust stack 26 and erected in China and Germany on the upper part of the reactor building 20, which is directly supported by the bedrock 21. While it is possible to reduce the seismic resistance level, the 5GTS piping section 2b (not shown), which was conventionally routed endlessly to the main exhaust n3 (see Figure 2), and the 5GTS piping trench 7 containing this, The number of artificial rocks 8 supported by the bedrock 21 can be reduced, and it is possible to significantly reduce the number of objects 1 and the number of construction man-hours associated with this.

(Effects of the Invention) As explained above, the present invention configures the exhaust port end of the emergency gas treatment system piping into an exhaust pipe, and connects the exhaust pipe to the upper part of the reactor building, which is directly supported by rock. It was erected.

Therefore, since the rock that directly supports the exhaust stack itself can be omitted, the number of support structures used for the main exhaust stack can be significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the overall configuration of an embodiment of a nuclear power plant according to the present invention, and FIG. 2 is a schematic diagram showing the overall configuration of a conventional nuclear power plant. 20... Nuclear reactor 11, 21... Bedrock, 22...
Leveling surface, 23... Exhaust stack, 24.27... Support structure, 25... Turbine building, 26... Main exhaust stack.

Claims (1)

[Claims] 1. A main exhaust stack that discharges air purified by each ventilation air conditioning system in the reactor building and turbine building to the outside air during normal times, and a main exhaust stack that replaces the reactor building ventilation air conditioning system in an emergency. In a nuclear power plant that has an emergency gas treatment system that automatically starts up, purifies the air inside the reactor building, and then discharges it to the outside air through piping, the exhaust port end of the emergency gas treatment system piping is configured as an exhaust stack. A nuclear power plant characterized in that the exhaust stack is erected at the upper part of the reactor building. 2. The nuclear power plant according to claim 1, wherein the main exhaust stack is erected at the upper part of the turbine building.