JPH0772281A - Emergency gas treatment device - Google Patents

Abstract

PURPOSE:To provide an emergency gas treatment device which does not leak air including radioactive material out of a reactor building even though the air in the reactor building expands and inner pressure increases during an accident of a reactor power plant. CONSTITUTION:An emergency gas treatment device has processing fans 5a, 5b to such in the air including radioactive material generating in a reactor building 2 through a piping 3, a processing filter device 7 to remove the radioactives, isolation valves 6a, 6b provided downstream of the treatment filter device 7, and reactor building outer walls 1 containing the reactor building 2. Also provided for constitution are an intake piping 25 guiding the air through an intake fan 12 and a control damper 16 into a space 21 in the double walls formed with this reactor building outer walls 1 and the reactor building 2, a differential pressure transmitter 14 to measure the differential pressure between the pressure in the space 21 in the double walls and the pressure in the reactor building 2 and transmit the differential pressure signal, and a differential pressure controller 15 controlling the opening of the control damper 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emergency gas treatment system for treating radioactive gas inside a nuclear reactor building to maintain a negative pressure in the nuclear reactor building in the event of a nuclear power plant accident.

[0002]

2. Description of the Related Art Generally, in a nuclear facility such as a nuclear power plant, various devices are installed in consideration of an accident. An emergency gas treatment device is one of the devices. This emergency gas processing system is designed to remove the radioactive material from the reactor stored in the reactor building, remove the radioactive material, and then remove it outside the reactor building. It is a device that maintains negative pressure inside the reactor building at the same time as discharging.

A conventional example of an emergency gas treatment device will be described below with reference to FIG. A reactor (not shown) is installed in the reactor building 2. In the unlikely event of a radioactive material leak in a nuclear reactor, a nuclear power plant is designed to isolate the nuclear reactor and prevent the radioactive material from leaking. At this time, the radioactive material already released into the reactor building 2 will be treated by the emergency gas treatment device. The emergency gas treatment device sucked in the pipe 3 for taking in the air in the reactor building 2 and the emergency gas treatment isolation valves 4a, 4b arranged in parallel with the pipe 3 and normally closed. It has emergency gas treatment fans 5a, 5b provided via heating coils 13a, 13b for removing moisture of air. The emergency gas treatment fans 5a and 5b are activated at the same time when the nuclear reactor is isolated, and continuously suck air to guide it to the emergency gas treatment filter device 7. The emergency gas treatment filter device 7 is a device for removing radioactive substances contained in air. The air from which the radioactive material has been removed is discharged from the exhaust stack 9 to the atmosphere through the emergency gas treatment isolation valves 6a and 6b arranged in parallel.

By continuously treating and discharging the air in the reactor building 2 in this manner, the reactor building 2 is maintained at a negative pressure more than the outside air, and the air containing the radioactive material is contained in the reactor building 2 Prevents leakage to the outside.

[0005]

In the above-mentioned conventional emergency gas treatment apparatus, when an accident occurs and vapor containing radioactive material is released from the nuclear reactor, the heat of the vapor is removed. There was a possibility that the volumetric expansion due to the temperature rise of the air could not be absorbed.

The present invention has been made in view of the above conventional circumstances, and an object thereof is to increase the internal pressure of the nuclear reactor building due to the expansion of the air inside the reactor building in the event of a nuclear power plant accident.
An object of the present invention is to provide an emergency gas treatment device in which air containing radioactive substances does not leak outside the reactor building.

[0007]

In order to achieve the above object, the emergency gas treatment apparatus of the present invention comprises:
In the described invention, a processing fan for sucking in air containing a radioactive substance generated in a reactor building in which a nuclear reactor is installed via a pipe, and a processing filter device for removing a radioactive substance from the sucked air. In an emergency gas treatment device having an isolation valve provided on the downstream side of this processing filter device, a reactor building outdoor wall disposed with a predetermined gap from the entire reactor building outdoor side, and this reactor An air supply pipe that is guided to a space inside the double wall formed by the building outdoor wall and the reactor building, and arranges an air supply fan and an adjustment damper on the way, and the pressure in the space inside the double wall and the reactor building. A differential pressure transmitter that measures the differential pressure of indoor pressure and transmits a differential pressure signal, and receives the differential pressure signal from this differential pressure transmitter to adjust the opening of the adjustment damper provided in the air supply pipe. Gas treatment with differential pressure regulator It is intended to provide a location.

According to the second aspect of the present invention, a processing fan for sucking air containing radioactive substances generated in the reactor building in which the nuclear reactor is installed through a pipe, and a radioactive substance for sucking the radioactive substances from the sucked air. In an emergency gas treatment device having a treatment filter device to be removed and an isolation valve provided on the downstream side of the treatment filter device, a reactor building arranged with a predetermined gap from the entire surface of the exterior side of the reactor building The outer wall,
The reactor building outdoor wall and a pipe for supplying air to the space inside the double wall formed by the reactor building through a check valve are provided, and this pipe is branched from the pipe for supplying air to the reactor building. The present invention provides an emergency gas treatment device, which is a branched pipe.

According to the third aspect of the present invention, a processing fan for sucking air containing radioactive substances generated in the reactor building in which the nuclear reactor is installed through a pipe and a radioactive substance from the sucked air. In an emergency gas treatment device having a treatment filter device to be removed and an isolation valve provided on the downstream side of the treatment filter device, a reactor building arranged with a predetermined gap from the entire surface of the exterior side of the reactor building The outer wall,
An air supply pipe having an end connected to a space inside the double wall formed by the reactor building outdoor wall and the reactor building, and the other end connected to the processing filter device and an isolation valve midway through an adjustment damper. And a differential pressure transmitter that measures the differential pressure between the pressure inside the double wall and the pressure inside the reactor building and sends a differential pressure signal, and receives the differential pressure signal from this differential pressure transmitter. There is provided an emergency gas treatment device having an adjustment damper provided in the air supply pipe and a differential pressure regulator for adjusting the opening of the isolation valve.

[0010]

In the emergency gas treatment device having the above structure, by pressurizing the inside of the double wall formed by the reactor building and the outdoor wall of the reactor building, an accident may occur in the reactor and Even if the air in the building expands and the internal pressure rises, a negative differential pressure can be maintained with respect to the pressure in the double wall. Therefore, the air containing radioactive materials will not leak outside the reactor building.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of an emergency gas processing apparatus according to the present invention will be described below with reference to FIG. In FIG.
The same parts as those shown in FIG. Reactor building 2 is the reactor building outdoor wall 1
Is surrounded by. Space 21 in the double wall formed by the reactor building 2 and the reactor building outdoor wall 1
A differential pressure pipe 20a is provided in the reactor, and is connected to the differential pressure transmitter 14 together with the differential pressure pipe 20b provided in the reactor building 2. This differential pressure transmitter 14 has a space 2 inside the double wall.
The differential pressure between the reactor 1 and the reactor building 2 is measured, and the measurement signal 14a is transmitted to the differential pressure controller 15. The differential pressure regulator 15 uses the air supply pipe 2 to maintain the differential pressure at a predetermined value.
The adjustment signal 15a is transmitted to the differential pressure adjusting air supply fan damper 16 provided in FIG. 5 to adjust the opening degree to control the amount of air supplied by the differential pressure adjusting air supply fan 12.

In the emergency gas processing system thus constructed, an accident occurs in a nuclear reactor (not shown) arranged in the nuclear reactor building 2 and a high temperature fluid containing radioactive substances is discharged. Then, the emergency gas processing fans 5a and 5b are activated and the air containing the radioactive material is sucked through the pipe 3 provided in the reactor building 2. The inhaled air is discharged from the exhaust stack 9 to the atmosphere after removing the radioactive substances by the emergency gas treatment filter device 7.

At this time, as the temperature of the air in the reactor building 2 rises due to the high temperature fluid discharged from the reactor, the volume of air expands and the pressure rises. The pressure in the reactor building 2 and the differential pressure in the space 21 in the double wall are monitored by the differential pressure transmitter 14, and the opening of the differential pressure adjusting air supply fan damper 16 is controlled by the differential pressure controller 15. By adjusting the amount of air supplied by the differential pressure adjusting air supply fan 12, the differential pressure is maintained at a predetermined constant value.

Therefore, it is possible to prevent the leakage of the air containing the radioactive material from the inside of the reactor building 2 to the inside of the double wall. Further, even if the radioactive material leaks from the inside of the reactor building 2, the outdoor wall 1 of the reactor building covers the reactor building 2, so the radioactive material is not released into the atmosphere.

Next, a second embodiment of the emergency gas processing system according to the present invention will be described with reference to FIG. 2, the same parts as those in FIG. 1 are designated by the same reference numerals, and the description of the configuration will be omitted. In order to ventilate the reactor building 2 to the reactor building 2, the air supply pipe 22 is provided inside the reactor building 2 from the reactor building air supply fans 8a and 8b through the reactor building air supply isolation valves 10a and 10b. Have been led to. The inside of the reactor building 2 is constantly supplied with air by the reactor building supply fans 8a and 8b. Therefore, the space 21 in the double wall can be pressurized by branching from the air supply pipe 22 and guiding the branch pipe 23 to the space 21 in the double wall via the reactor building air supply check valve 11. Generally, an exhaust device for ventilation and air conditioning is provided in the reactor building 2, so even if air is supplied from the same air source, the pressure in the space 21 in the closed double wall is increased to increase the It is possible to give a differential pressure to the inside of the furnace building 2.

Therefore, even in the unlikely event of an accident, the pressure in the space 21 in the double wall can be maintained higher than the pressure in the reactor building 2, and the air containing the radioactive substance is released from the inside of the reactor building 2. Can be prevented from leaking.

Next, a third embodiment of the present invention will be described with reference to FIG. In FIG. 3, the same parts as those in FIG. 1 are designated by the same reference numerals, and the description of the configuration will be omitted. The present invention provides an emergency gas treatment in the space 21 in the double wall formed by the reactor building 2 and the reactor building outdoor wall 1 by providing the air supply pipe 24 from the discharge side pipe 3 of the emergency gas treatment filter device 7. It is connected via a regulating valve 19. The emergency gas treatment adjusting valve 19 is a valve whose opening is adjusted by the differential pressure adjuster 15. This differential pressure regulator 15 is used for the space 2 in the double wall.
1 receives the differential pressure signal from the differential pressure transmitter 14 which measures the differential pressure between the air in the reactor building 2 and the differential pressure signal,
Emergency gas processing adjustment valve 19 and emergency gas processing isolation valve 6
Adjust the opening of a and 6b.

In the emergency gas treatment system thus constructed, in the unlikely event that air containing radioactive substances is released due to a nuclear reactor accident, the emergency gas treatment fans 5a and 5b are separated from the reactor building 2 at the same time. At the same time, the emergency gas processing isolation valves 4a and 4b are opened. The air containing the radioactive substance in the reactor building 2 is introduced into the space 21 in the double wall through the emergency gas treatment adjusting valve 19 after removing the radioactive substance by the emergency gas treatment filter device 7.

At this time, when the differential pressure measured by the differential pressure transmitter 14 is equal to or less than a predetermined value and there is a possibility of leakage of radioactive material from the inside of the reactor building 2, the differential pressure regulator 15 The emergency gas processing adjustment valve 19 is instructed to increase the opening degree, and the emergency gas processing isolation valves 6a and 6b are instructed to decrease the opening degree.

On the other hand, if the differential pressure of the differential pressure transmitter 14 is equal to or greater than a predetermined value, the differential pressure regulator 15 will give a reverse instruction. Therefore, by maintaining the emergency gas processing adjustment valve 19 and the emergency gas processing isolation valves 6a and 6b at appropriate opening levels,
The pressure difference between the air in the space 21 inside the double wall and the air in the reactor building 2 can be maintained at a predetermined value, and even if thermal expansion of air occurs during a nuclear reactor accident, radioactive materials leak to the outside of the reactor building 2. There is no such thing.

[0021]

As described above, in the emergency gas treatment system of the present invention, it is possible to prevent leakage of radioactive substances released in the event of a nuclear reactor accident to the atmosphere and to contribute to the reduction of radiation exposure. be able to.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of an emergency gas treatment device of the present invention.

FIG. 2 is a configuration diagram showing a second embodiment of an emergency gas treatment device of the present invention.

FIG. 3 is a configuration diagram showing a third embodiment of an emergency gas treatment device of the present invention.

FIG. 4 is a configuration diagram showing a conventional example of an emergency gas treatment device.

[Explanation of symbols]

1 ... Reactor building outdoor wall 2 ... Reactor building 3 ... Piping 4a, 4b ... Emergency gas treatment isolation valve 5a, 5b ... Emergency gas treatment fan 6a, 6b ... Emergency gas treatment isolation valve 7 ... Emergency gas treatment filter Devices 8a, 8b ... Reactor building air supply fan 9 ... Exhaust tubes 10a, 10b ...
Reactor building air supply isolation valve 11 ... Reactor building air supply check valve 12 ... Differential pressure adjusting air supply fan 13a, 13b ... Heating coil 14 ... Differential pressure transmitter 14a ... Differential pressure signal 15 ... Differential pressure controller 15a ... adjustment signal 16 ... differential pressure adjusting air supply fan damper 18 ... duct 19 ... emergency gas treatment adjusting valve 20a, 20b ... differential pressure pipe 21 ... space 22 ... air supply pipe 23 ... branch pipe 24 ... air supply pipe 25 ... Air supply piping

Claims (3)

[Claims] 1. A processing fan for sucking air containing a radioactive substance generated in a reactor building inside a reactor through a pipe, and a processing filter device for removing the radioactive substance from the sucked air. In an emergency gas treatment device having an isolation valve provided on the downstream side of this processing filter device, a reactor building outdoor wall disposed with a predetermined gap from the entire reactor building outdoor side, and this reactor An air supply pipe that is guided to a space inside the double wall formed by the building outdoor wall and the reactor building, and arranges an air supply fan and an adjustment damper on the way, and the pressure in the space inside the double wall and the reactor building. A differential pressure transmitter that measures the differential pressure of indoor pressure and transmits a differential pressure signal, and receives the differential pressure signal from this differential pressure transmitter to adjust the opening of the adjustment damper provided in the air supply pipe. And a differential pressure controller for Service gas treatment equipment. 2. A processing fan for sucking air containing radioactive substances generated in a reactor building inside a reactor through a pipe, and a processing filter device for removing radioactive substances from the sucked air. In an emergency gas treatment device having an isolation valve provided on the downstream side of this processing filter device, a reactor building outdoor wall disposed with a predetermined gap from the entire reactor building outdoor side, and this reactor A building outdoor wall and a pipe for supplying air through a check valve to a space inside the double wall formed by the reactor building, and this pipe is a branch pipe branched from the pipe for supplying air to the reactor building. An emergency gas processing device characterized in that 3. A processing fan for sucking air containing radioactive substances generated in a reactor building inside a nuclear reactor through a pipe, and a processing filter device for removing radioactive substances from the sucked air. In an emergency gas treatment device having an isolation valve provided on the downstream side of this processing filter device, a reactor building outdoor wall disposed with a predetermined gap from the entire reactor building outdoor side, and this reactor An air supply pipe having an end connected to a space in a double wall formed by a building outdoor wall and the reactor building and the other end connected to the processing filter device and an isolation valve midway through an adjustment damper; A differential pressure transmitter that transmits a differential pressure signal by measuring the differential pressure between the pressure inside the double wall and the pressure inside the reactor building, and receives the differential pressure signal from this differential pressure transmitter to supply the air. Adjustment damper provided in the pipe and the isolation valve And a differential pressure regulator for adjusting the opening degree of the emergency gas treatment apparatus.