JPH04369496A - Ventilation and air conditioning system for reactor power plant turbine buildinc - Google Patents

Abstract

PURPOSE:To lower construction cost and operation cost of a ventilation and air conditioning system for a reactor power plant turbine building by reducing the capacity of exhaust fan and exhaust duct or a main exhaust system and the like and eliminating such auxilially equipment as rooftop ventilation fan, and economize and promote safety by reducing the radioactive waste mass such as spent filter and preventing the unbalancing of the air flow in the turbine building. CONSTITUTION:Main ventilation and air conditioning means 2, 4 are provided to ventilate and condition the air in the operation floor 3 of a turbine building by natural convection ventilation during a normal operation. Auxilially ventilation and air conditioning means ventilates and conditions the operation floor 3 in the tubine building during a regular inspection by exhausting through the main stack 1 by way of special exhaust systems 6, 8, 10 for the operation floor of the turbine building or the ventilation and air conditioning exhaust system 11, 12 for the turbine area (contaminated area) 5A in the turbine building.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to ventilation and air conditioning equipment for a turbine building of a BWR nuclear power plant.

0002

2. Description of the Related Art A conventional nuclear power plant turbine building ventilation air conditioning system is shown in FIG. In FIG. 5, outside air is taken in by an air supply fan 7 through an outside air processing device (supply air filter) 9, and after cooling each room, the exhaust air from the turbine building 5 is treated by each exhaust processing device (exhaust filter) 11. Thereafter, the air is sent to the main exhaust stack 1 by a common exhaust fan 12, and diffused into the atmosphere.

[0003] Furthermore, in the "ventilation system for a turbine building" described in JP-A No. 61-105488, the turbine building is divided into two sections with a confidential operating floor, and the operating floor of the turbine building during normal operation is divided into two parts. The ventilation air conditioning system is a system in which air is supplied from the air inlet on the wall of the turbine building operating floor and exhausted from the ventilation fan on the roof. Sometimes, the ventilation fan on the rooftop is closed and the entrance for large items on the operating floor is opened to communicate the operating floor space with the space below, and a backup exhaust fan is additionally operated to exhaust the air.

Furthermore, in the "nuclear power plant turbine building equipped with ventilation equipment" described in Japanese Patent Publication No. 1-40316, the ventilation air conditioning of the operating floor of the turbine building during normal operation is controlled by the air conditioner installed on the operating floor. With the lid closed, air is supplied from the air inlet on the wall of the turbine building operating floor and exhausted from the rooftop ventilation fan, while ventilation of the contaminated area, including the condenser area downstairs, is provided in the contaminated area. The condenser area is supplied with air from the air supply duct, the condenser area is brought under negative pressure, the air is guided to the condenser area, and then the air is discharged to the atmosphere from the main exhaust stack through the exhaust duct connected to the outdoor exhaust equipment. This is done using a system called. In addition, when the reactor is shut down during periodic inspections, etc., the ventilation air conditioning on the operating floor of the turbine building is supplied through an air supply port installed on the wall of the operating floor of the turbine building, and the Open the main door (large equipment entrance) and send the exhaust air to the contaminated area, including the condenser area.
Furthermore, the system uses a system in which the air is released into the atmosphere from the main exhaust stack through an exhaust duct leading to the exhaust equipment.

[0005]

[Problems to be Solved by the Invention] In the ventilation air conditioning equipment shown in FIG. 1, the exhaust gas from the turbine during normal operation is sent to the main exhaust stack through the exhaust filter 11 in both the turbine area (contaminated area) 5A in the turbine building and the operation floor 5. 12, the pressure loss in the exhaust filter, exhaust duct, and main exhaust stack becomes large, and a large capacity air supply fan and exhaust fan are required. Furthermore, since the flow rate of the main exhaust stack 1 is large, the main exhaust stack needs to have a large diameter, and an air supply duct 16 on the operation floor 3 of the turbine building is also required. Therefore, construction costs and operating costs increase. In addition, because the same exhaust system treats highly contaminated areas in the turbine building and low-contaminated areas such as the operating floor of the turbine building, a large amount of used filters are generated as low radioactive waste, reducing the amount of radioactive waste. To increase. In addition, the ventilation air conditioning equipment described in Japanese Patent Application Laid-open No. 105488/1988 and Japanese Patent Publication No. 40316/1998 is designed to exhaust air from the operating floor of the turbine building using a rooftop ventilation fan during normal operation. In addition to increasing costs and operating costs, during periodic inspections or when radioactivity rises on the operating floor of the turbine building, open the airtight lid installed on the floor of the operating floor of the turbine building and remove the air from the contaminated area within the turbine building. Since the system is designed to exhaust air,
There is a problem in that the air volume balance in the contaminated area within the turbine building is disrupted.

[0006] A first object of the present invention is to provide a nuclear power plant turbine building ventilation air conditioning system that reduces the capacity of the exhaust system such as an exhaust fan, exhaust duct, or main exhaust stack, and reduces construction and operating costs. That's true.

A second object of the present invention is to provide a nuclear power plant turbine that allows the capacity of the exhaust system to be reduced without using incidental equipment such as rooftop ventilation fans and without destroying the air volume balance. The purpose is to provide building ventilation and air conditioning equipment.

[0008]

[Means for Solving the Problems] A nuclear power plant turbine building ventilation air conditioning system according to the present invention includes an air supply port provided on an outer wall of a turbine building operation floor and a position higher than the air supply port on the outer wall. a first ventilation air-conditioning means, which has an exhaust port provided in the air supply port, and performs ventilation and air conditioning of the operating floor of the turbine building through natural circulation ventilation in which air is supplied from the air supply port and exhausted from the exhaust port during normal operation; and a second ventilation air-conditioning means for ventilation and air-conditioning the operating floor of the turbine building by supplying air from the air supply port and exhausting air from the main exhaust stack. The second ventilation air-conditioning means may include means for providing an exhaust system exclusively for the turbine building operating floor that is provided with a separate exhaust fan connected to the main exhaust stack, or for preventing contamination within the turbine building from contaminating the turbine building operating floor. The exhaust system can be configured to be selectively communicated with the area exhaust system, so that the exhaust system can be shared between the contaminated area in the turbine building and the operation floor of the turbine building during periodic inspections.

[0009]

[Function] The first step is to ventilate and air-condition the turbine building operating floor using natural circulation ventilation during normal operation when there is little radioactive release from the turbine building operating floor, but a large amount of heat is generated from the equipment.
By providing ventilation air conditioning means, the capacity of exhaust systems such as exhaust fans, exhaust ducts, or main exhaust stacks can be reduced.
Additionally, there is no need for incidental equipment such as rooftop ventilation fans, reducing construction and operating costs. Additionally, the amount of low-radioactive waste such as used filters can be reduced. Furthermore, by exhausting air from the main exhaust stack through the exhaust system dedicated to the turbine building operating floor during periodic inspections, the turbine building operating floor space and the contaminated area space inside the turbine building are isolated, so that the contaminated area inside the turbine building is This prevents the air volume from becoming unbalanced.

0010

Embodiments Examples of the present invention will be described below with reference to FIGS. 1 to 4.

FIGS. 1 and 2 are diagrams of a turbine building in a nuclear power plant according to an embodiment of the present invention, with FIG. 1 showing the state during normal operation and FIG. 2 showing the state during periodic inspection. The turbine building 5 is separated into a turbine area 5A forming a contaminated area within the turbine building and a turbine building operating floor 3.

As ventilation air conditioning equipment for the operation floor 3 of the turbine building, there are an air supply port 2 and an exhaust port 4 each equipped with a louver.
, exhaust duct 6, exhaust filter 8, operating floor exhaust fan 1
0, and a check valve 14 for preventing backflow of the exhaust system on the operating floor of the turbine building. The air supply port 2 and the exhaust port 4 are
The exhaust duct 6, the exhaust filter 8, the operating floor exhaust fan 10, and the check valve 14 constitute the first ventilation air conditioning means that performs ventilation and air conditioning of the operating floor of the turbine building through natural circulation ventilation during normal operation. Air is supplied from air supply port 2 to main exhaust stack 1
A second ventilation air-conditioning means is configured to ventilate and air-condition the operating floor 3 of the turbine building by exhausting the air.

Further, as ventilation air conditioning equipment for the turbine area 5A, an air supply processing device 9, an air supply fan 9, an exhaust filter 11, and an exhaust fan 12 are provided.

Ventilation air conditioning for the turbine area 5A is as follows:
Supply air processing device 9, supply air fan 9 during normal operation and periodic inspection
Air is supplied through the main exhaust pipe 1 via an exhaust filter 11 and an exhaust fan 12.

Ventilation and air conditioning of the operation floor 3 of the turbine building is performed as follows. During normal operation, air supply to the operating floor 3 of the turbine building is introduced through the air supply port 2 provided on the outer wall, and exhaust air is discharged through the exhaust port 4 provided on the outer wall surface. In this case, the driving force for natural circulation ventilation is the temperature difference between the inside and outside of the building, and the ventilation power due to that temperature difference is, as shown in Volume II of the Air Conditioning and Sanitary Engineering Handbook,

[0016]

[Equation 1] Pt=h(γ0−γi) (1) It is given by: However, here Pt: Ventilation power due to temperature difference
[mmAq]h: Difference in height between air supply port and exhaust port
[m] γ0: Density of air outside the building [kg/m3]
γi: Density of air inside the building
[kg/m3].

Since the turbine 13 is installed on the turbine building operation floor 3, a large amount of heat is generated during operation of the plant, warming the indoor air. Therefore, natural circulation ventilation occurs due to the difference in density of air outside the building. In this case, as shown in the above-mentioned theoretical formula, regarding the height difference h between the air supply port and the exhaust port, the air supply port is set as low as possible, and the exhaust port is set as high as possible to increase h. It is preferable to increase ventilation power.

During periodic inspections, when inspecting the turbine rotor, etc., the turbine casing 13 is opened, so a small amount of radioactive material adhering to the inside of the casing and the turbine blades is scattered, making the surrounding area and air radioactive. There is a possibility of contamination. Therefore, it is necessary to avoid releasing radioactivity directly to the outdoors from the exhaust port 4 during the regular inspection period. In the embodiment shown in FIG. 2, in this case, the exhaust port 4 is automatically or manually closed, and the operating floor exhaust fan 10 provided in the exhaust system exclusively for the turbine building operating floor is operated. 3 to exhaust duct 6,
It is discharged outdoors from the main exhaust stack 1 via the exhaust filter 8 and the operating floor exhaust fan 10. When radioactivity is released from the main exhaust stack 1 and when it is released from the exhaust port 4,
The effect of radioactivity diffusion before reaching the site boundary is different, and if the radioactivity release rate is the same, in this example where radiation is released from the main exhaust stack 1, the exposure amount is reduced by 1 compared to the case where radiation is released from the exhaust port 4. /10.

The situation when the radioactivity concentration on the operating floor increases during operation will be explained with reference to FIG. In the unlikely event that the radioactivity concentration in the exhaust gas on the operating floor 1 of the turbine building increases for some reason during operation, this will be detected by the radiation monitor and an alarm will be issued in the central control room. This alarm causes the exhaust port 4
Automatically or manually close the operation floor exhaust fan 10.
Activate. Air in the turbine building operating floor 1 is supplied through an air supply port 2, and is exhausted from the main exhaust stack 1 by an operating floor exhaust fan 10 via an exhaust filter 8.

In the above embodiment, in order to utilize natural circulation ventilation in which the exhaust gas from the turbine building operation floor 3, which was previously released from the main exhaust stack 1 during normal operation, is directly released from the exhaust port 4, the main exhaust stack 1 The amount of emissions from the plant can be reduced by about 20% from the current plant's approximately 600,000 m3/h to 500,000 m3/h. From this, the diameter of the main exhaust stack 1 is 90%
The air intake fan 7 and exhaust fan 12 can both be reduced to approximately 80
% capacity, and also eliminates the need for air supply ducts on the operating floor of the turbine building. Additionally, the processing capacity of the exhaust filter 11 installed in front of the exhaust fan 12 is approximately 8
0%, the amount of used filters generated as low-radioactive waste is also reduced to 80%. Therefore, both construction costs and operating costs are significantly reduced.

Therefore, according to this embodiment, by providing natural ventilation on the operation floor of the turbine building during normal operation, there is no need for incidental equipment such as a rooftop ventilation fan, and the exhaust fan 12 and exhaust duct on the turbine area 5A side are Alternatively, the capacity of the exhaust system such as the main exhaust stack 1 can be reduced, making it possible to reduce construction costs and operating costs. Furthermore, low-radioactivity waste such as the exhaust filter 11 is also reduced. Furthermore, when heat generation from equipment is low during periodic inspections, the exhaust is exhausted outdoors from the main exhaust stack 1 via the exhaust system dedicated to the turbine building operation floor, so the capacity of this exhaust system can be reduced, reducing construction and operating costs. reduction is possible. Moreover, since the exhaust air from the operating floor 3 is not carried out via the turbine area 5A, it is possible to prevent the air volume balance of the turbine area 5A from being unbalanced. Additionally, the amount of low-radioactive waste such as used filters can be reduced.

Next, another embodiment of the present invention will be explained with reference to FIG. Figure 3 shows the periodic inspection. As ventilation air conditioning equipment for the turbine building operating floor 3, there are an air supply port 2 and an exhaust port 4 each equipped with a louver, an exhaust duct 17 for making the exhaust air from the turbine building operating floor join the exhaust system of the turbine area 5A, and an exhaust duct. A valve 15 that opens and closes 17 is provided. The air supply port 2 and the exhaust port 4 constitute a first ventilation air conditioning means that performs ventilation air conditioning of the operating floor of the turbine building by natural circulation ventilation during normal operation, as in FIGS. 1 and 2,
The exhaust duct 17 and the valve 15 constitute a second ventilation air conditioning means that supplies air from the air supply port 2 during periodic inspections and shares the exhaust system with the contaminated area inside the turbine building and the operating floor of the turbine building. In addition, the ventilation air conditioning equipment for turbine area 5A is shown in Figure 1.
and the same as in FIG.

The ventilation and air conditioning of the turbine area 5A and the turbine building operating floor 5 during normal operation and the ventilation and air conditioning of the turbine area 5A during regular inspections are the same as in the previous embodiment.

Ventilation and air conditioning of the operating floor of the turbine building during periodic inspections is performed as follows. During regular inspections, most of the equipment that generates heat during normal operation, such as condensers and feed water heaters, is stopped, so there is little need for heat removal. Therefore, during regular inspections, the valve 15 provided in the exhaust duct 17 is opened,
The exhaust gas from the turbine building operation floor 3 is merged into the ventilation air conditioning equipment exhaust system of the turbine area 5A, that is, the exhaust filter 11
and discharged from the main exhaust stack 1 via the exhaust fan 12. In this case, the performance of the exhaust filter 11 and the exhaust fan 12 may be the same as that during normal operation, since the heat generation is small as described above. In this case, exhaust may be performed using an airtight lid (large equipment entrance) provided on the floor of the operating floor of the turbine building, instead of using the exhaust duct 17 or the valve 15.

According to this embodiment, similarly to the previous embodiment,
By providing natural ventilation to the operating floor of the turbine building during normal operation, there is no need for incidental equipment such as rooftop ventilation fans.
It is possible to reduce construction costs and operating costs.

Still another embodiment of the present invention will be explained with reference to FIG. In this embodiment, during both normal operation and periodic inspection, air is supplied from an air supply port provided on the outer wall of the turbine building, and a separately installed exhaust filter 8 and an exhaust fan on the operating floor dedicated to the operating floor of the turbine building are used. The gas is discharged from the main exhaust stack 1 via the pipe 10. Therefore, the exhaust port as in the above two embodiments is not required.

According to this embodiment, the turbine building operating floor 3
Since the ventilation system of the turbine area 5A is completely shut off, it is possible to prevent the air volume balance of the entire turbine building from being disrupted, and a high level of safety can be ensured.

[0028]

[Effects of the Invention] According to the present invention, the capacity of the exhaust system such as the exhaust fan, exhaust duct, or main exhaust system is reduced, and additional equipment such as rooftop ventilation fans is not required, thereby reducing construction costs and operating costs. can be reduced. Also,
The amount of low radioactive waste such as used filters can be reduced. Furthermore, since the exhaust is exhausted from the main exhaust stack via the exhaust system dedicated to the turbine building operation floor during periodic inspections, it is possible to prevent the air volume from becoming unbalanced. Therefore, it is possible to provide a nuclear power plant turbine building ventilation air conditioning system that is highly economical and highly safe.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing ventilation air conditioning equipment during normal operation of a nuclear power plant turbine building according to an embodiment of the present invention.

FIG. 2 is a diagram showing ventilation and air conditioning equipment during regular inspections of the nuclear power plant turbine building shown in FIG. 1;

FIG. 3 is a diagram showing ventilation air conditioning equipment during periodic inspections of a nuclear power plant turbine building according to another embodiment of the present invention.

FIG. 4 is a diagram showing ventilation and air conditioning equipment for a turbine building of a nuclear power plant according to still another embodiment of the present invention.

FIG. 5 is a diagram showing a ventilation air conditioning system for a turbine building of a nuclear power plant according to the prior art.

[Explanation of symbols]

1 Main exhaust stack 2 Air supply port 3 Turbine building operating floor 4 Exhaust port 5 Turbine building 5A Turbine area (contaminated area) 8 Exhaust filter 10 Driving floor exhaust fan 12 Exhaust fan

Claims (4)

[Claims] Claims: 1. An air supply system having an air supply port provided on an outer wall of an operating floor of a turbine building, and an exhaust port provided on the outer wall at a higher position than the air supply port, the air supply port being higher than the air supply port during normal operation. a first ventilation air conditioning means for ventilation and air conditioning the operating floor of the turbine building through natural circulation ventilation in which air is supplied and exhausted through the exhaust port; The second air conditioner provides ventilation and air conditioning on the operating floor of the building.
Nuclear power plant turbine building ventilation and air conditioning equipment, characterized in that it is equipped with ventilation and air conditioning means. 2. The second ventilation air conditioning means has an exhaust system dedicated to the turbine building operating floor, which is provided with a separate exhaust fan connected to the main exhaust stack.
Nuclear power plant turbine building ventilation air conditioning equipment described. 3. The second ventilation air conditioning means includes means for selectively communicating the turbine building operating floor with an exhaust system for a contaminated area within the turbine building, and the second ventilation air conditioning means includes means for selectively communicating the operating floor of the turbine building with an exhaust system for a contaminated area within the turbine building, and the exhaust system is connected to an exhaust system for a contaminated area within the turbine building during regular inspections. The nuclear power plant turbine building ventilation air conditioning system according to claim 1, characterized in that it is shared by the turbine building operating floor and the turbine building operation floor. 4. An exhaust system exclusively for the turbine building operating floor, which is connected to an air supply port and a main exhaust stack provided on the outer wall of the turbine building operating floor, and is equipped with an exhaust fan, which is used during normal operation and regular operation. A nuclear power plant turbine building ventilation and air conditioning system, characterized in that air is supplied from the air supply port during each inspection, and is exhausted from the main exhaust stack via an exhaust system dedicated to the turbine building operation floor.