JPS6333193Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to reactor building ventilation and air conditioning equipment for boiling water reactors, and in particular, to provide the same air conditioning system for the secondary containment vessel area and the annex area of the reactor building. The present invention relates to air conditioning equipment suitable for air conditioning.

[Prior art]

Examples of the prior art are shown in FIGS. 1 and 2.

The example shown in Figure 1 is a system in which the secondary containment area and the annex area of the reactor building are operated by the same ventilation and air conditioning equipment. In Figure 1, the outside air is fan 3 or 4.
The air is taken in through the outside air processing device 1 , the flow rate is controlled to be constant by the flow rate detector 33 , the flow rate controller 34 , and the damper 31 or 32 , and then sent to the secondary containment vessel 7 and the attached building 18 . The exhaust from the secondary containment vessel 7 and the attached building 18 is handled by the exhaust treatment device 11 or 1.
After being processed in step 2, it is sent to an exhaust stack 16 by a fan 13 or 14 and released into the atmosphere. Juan 13
Alternatively, the flow rate of the air at outlet 14 is controlled to be constant by a flow rate detector 37 and a flow rate controller 38. The purpose of the constant flow rate control is to maintain the pressure inside the secondary containment vessel 7 at a predetermined negative pressure and to prevent air containing radioactive dust from leaking outside the building.

In addition, valves 4 and 5 are installed in the duct 6 of the air supply line of the secondary containment vessel 7, and valves 4 and 5 are installed in the duct 10 of the exhaust line.
Valves 8 and 9 are provided in series, respectively, and by closing these valves in the event of a nuclear reactor accident or fuel handling accident, leakage of radioactive materials from the secondary containment vessel area is prevented. Closing these valves will completely stop the ventilation and air conditioning equipment, so the attached building 18
It also becomes impossible to ventilate the interior.

Therefore, the prior art example shown in FIG. 1 has the following drawbacks.

1. In the event of a nuclear reactor accident, the isolation valve will be closed and the ventilation system will stop, making it impossible to ventilate attached buildings that require ventilation even in the event of an accident.

2. A flow rate control device to maintain negative pressure inside the building is required to handle atmospheric airflow, and is also required for air supply and exhaust, making the equipment too large.

Figure 2 shows a case in which the air conditioning systems for the secondary containment vessel area and the annex area are made into separate systems in order to compensate for drawback 1 of the example in Figure 1 above, but in this case, even more equipment is required than in the example in Figure 1. is becoming excessive.

[Purpose of invention]

The purpose of the present invention is to install a negative pressure control device equipped with a fan to effectively exert its control action and the exhaust action of the fan.
To provide ventilation and air conditioning equipment in which the ventilation and air conditioning of the secondary containment vessel area of a nuclear reactor building and the annex building area are performed using the same equipment and the equipment has a simple configuration.

[Summary of the idea]

If the secondary containment area and the annex area of the reactor building are ventilated by the same ventilation air conditioning equipment, the isolation valve installed at the entrance to the secondary containment area will be closed in the event of a reactor accident. As a result, the ventilation system would stop, and the areas in the annex that would require ventilation in the event of a reactor accident would also be unable to be ventilated. The reason why the ventilation system has to be shut down in the event of a reactor accident is that the ventilation volume in the annex area is smaller than that in the secondary containment vessel area, which is about 10-25% of the total ventilation volume.

The present invention, as a means to eliminate the above-mentioned drawbacks,
By installing a dedicated negative pressure control device in the building equipped with a fan and providing this fan with the necessary ventilation capacity for the annex area, it is possible to maintain the ventilation capacity of the annex area even when the secondary containment vessel area is isolated. This is what I did.

[Example of idea]

FIG. 3 shows an example of implementation of the invention.

The outside air is supplied to the outside air processing device 1 by the fan 2 or 3.
is taken in through the duct 6 and duct 17 into the secondary containment vessel 7 and the attached building 18,
Provide necessary ventilation. After the required ventilation, the exhaust gas is sucked in by a fan 13 or 14, treated by an exhaust treatment device 11 or 12, and then passed through a duct 15 and released into the atmosphere from an exhaust stack 16.

One each of fans 2 and 3 and fans 13 and 14 are spares, in case of a stoppage due to a single failure of a dynamic device or
It is designed to maintain functionality even when the fan is stopped due to maintenance. Juan 2, 3, 13,
Check dampers 28, 29, 30, 3 are installed at the exit of 14.
1 is installed.

Valves 4 and 5 and valves 8 and 9 are installed in the air supply side duct 6 and the exhaust side duct 10 to isolate the secondary containment vessel in the event of a reactor accident.

Exhaust treatment device 23, fan 24, differential pressure controller 2
2 is provided for correcting the flow rate so that pressure fluctuations within the building will not occur due to unbalanced air supply and exhaust flow rates. Also, the capacity of fan 24 is the same as that of attached building 1.
By operating the fan 24, the ventilation function in the annex 18 can be maintained even when the main ventilation system is stopped when the secondary containment vessel 7 is isolated.

When the valves 4, 5, 8, and 9 are closed during a nuclear reactor accident, the closing signal causes the bypass dampers 20 of the air supply fans 2 and 3 to open, and the damper 25 at the outlet of the fan 24 to open. , Annex 1
8 ventilation is maintained.

According to one embodiment of the present invention, the following effects can be obtained.

1. Ventilation of the attached building can be maintained even during isolation of the secondary containment vessel.

2. Flow control devices for air supply and exhaust systems can be eliminated.

3. Ventilation equipment dedicated to the annex building can be eliminated.

[Effect of idea]

According to the present invention, the secondary containment area and the annex area of the reactor building can be ventilated with the same equipment, and the configuration and scale of the ventilation air conditioning equipment can be simplified and reduced.

[Brief explanation of the drawing]

1 and 2 are system configuration diagrams of an embodiment of the prior art, and FIG. 3 is a system configuration diagram of an embodiment of the present invention. 1,39...Outside air processing device, 2,3,13,1
4, 24, 40, 41, 48, 49... Juan.
4, 5, 8, 9, 26... Valve, 6, 10, 15,
17, 19, 21, 54... Duct, 7... Secondary containment vessel, 11, 12, 23, 46, 47... Exhaust treatment device, 16... Exhaust stack, 18... Annex building,
20, 25, 31, 32, 35, 36, 50, 5
1... Damper, 22... Differential pressure controller, 27...
Pipe, 28, 29, 30, 31... Check damper, 3
3, 37, 45, 52...Flow rate detector, 34, 3
8, 44, 53...Flow rate controller.

Claims (1)

[Scope of utility model registration request] A reactor building ventilation and air conditioning system shared by the reactor building secondary containment vessel and an annex, which provides ventilation and air conditioning by a first-class ventilation system consisting of an intake outside air treatment device, an air supply fan, an exhaust treatment device, an exhaust fan, etc., characterized in that it is equipped with a ventilation fan for the annex when maintaining negative pressure within the building and isolating the secondary containment vessel, and a negative pressure control damper and negative pressure controller.