JPS63263337A - Ventilating and air-conditioning apparatus in atomic power plant - Google Patents

Abstract

PURPOSE:To permit stabilized control of flow rate of air and maintenance of pressure difference between buildings without being affected by external disturbance upon effecting the control of flow rate of air, such as the reduction of flow rate of air due to the clogging of a filter or the like, by controlling an exhauster in accordance with the flow rate of air at the delivery side of a fan. CONSTITUTION:The control of the flow rate of air in an ventilating and air-conditioning system is effected by detection the flow rate of feeding air by air flow rate detectors 20a, 20b and controlling a suction vane 23 based on detecting signals. A pressure difference between buildings is set by keeping the buildings in a negative pressure by the initial opening degree of the suction vane 23. When the resistance of an air feeding duct 7 is increased by the clogging of a bag pipe 4 or the like, the reduction of the flow rate of air in the system is detected by the detectors 20a, 20b and the opening degree of the suction vane 23 is regulated into opening direction based on the detecting signals of the detectors. According to this method, an increment the resistances of the devices in an air feeding system is compensated by the capacity increase of an exhauster 12, whereby the flow rate of air in the system is controlled in constant. In this case, the negative pressure in the building is increased than the initial condition thereof; therefore, contaminated air will never be leaked to the outside of the building.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a ventilation air conditioner in a nuclear power plant, and particularly to an improvement in air volume control equipment.

(Prior art) Ventilation and air conditioning systems in nuclear power plants maintain the environment necessary for the normal operation of each equipment in the plant, and
Environmental conditions suitable for operators and workers (indoor temperature, humidity, etc.)
cleanliness, ventilation flow, etc.).

3 to 5 show this type of conventional ventilation air conditioner, in which a louver 2 is attached to an outside air intake port 1a provided in a building 1, and outside air is taken into a supply air processing device 3. Rainwater is prevented from entering the building 1.

Inside the supply air processing device 3, a bug-type filter 4 for removing foreign substances such as dust and particulate salt from the outside air, and a heating coil 5 and a cooling coil 6 for controlling the temperature of the outside air are installed. After being processed by the supply air processing device 3, the outside air passes through the supply air duct 7, which passes through the damper 7a, and is sent by the blower 8 to a space with a high radiation level (a so-called contaminated area) or an open field (where no radioactive materials exist). Air is supplied to each air conditioning section 9 of the so-called clean area.

By the way, in the case of air conditioning for contaminated areas, the purpose is to prevent radioactive materials from stagnation in the air conditioned space 9. Therefore, as shown in Figures 3 and 4, air conditioning is carried out from the air supply duct 7. The same volume of air as the air supplied to the space 9 is discharged outdoors from an exhaust stack 13 by an exhaust fan 12 through an exhaust duct 11 equipped with an exhaust treatment device 10 having a bag-type filter 10a and a high-performance particle filter 10b. A one-sole method is adopted.

In the conventional ventilation air conditioner for a nuclear power plant having the above configuration, air volume control and building differential pressure adjustment are performed by the following method.

That is, the outside air is sent to the air conditioned space 9 after being processed by the supply air processing device 3, and the amount of air sent is determined by the aero eye type air volume detector 14 installed at the outlet side of the blower 8 of the air supply duct 7. is detected, and the air volume control damper 15 on the side of the blower for eight people is set so that the air flow becomes the set jl-air volume using the regulator 16.

Furthermore, the building differential pressure is manually set by adjusting the supply and exhaust air units when setting the air volume so that the pressure inside the building becomes negative in contaminated areas.

During normal operation, the air supply treatment device 3 and the exhaust treatment device 10
In order to correct clogging of the bug-type filters 4 and 10a inside, the air volume control damper 15 is manually operated.

(Problems to be Solved by the Invention) In the conventional ventilation air conditioning system for nuclear power plants having the above configuration, air volume control during normal operation is intermittent, and setting the air volume takes time, so it is difficult to actually The reality is that the settings are only reset when replacing the filter.

In addition, increases and decreases in the air supply amount due to filter clogging and outside temperature fluctuations may cause disturbances in maintaining the building differential pressure at a negative pressure, and there is a risk that the health of the ventilation air conditioning system may not be maintained.

The present invention has been made in consideration of these points, and is capable of stably controlling air volume and maintaining building differential pressure without being affected by external disturbances such as reduction in air volume due to filter clogging. The purpose is to provide a ventilation air conditioning system in a nuclear power plant that can perform

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a ventilation air conditioner for a nuclear power plant, in which an air volume control means having at least an air volume detector and an air volume controller is provided on the discharge side of a blower, and ,
It is characterized in that an air volume control mechanism controlled by this air volume control means is provided.

(Function) In the ventilation air conditioner for a nuclear power plant according to the present invention, the amount of air sent to the air-conditioned space is detected by the air amount control means installed on the discharge side of the blower.

Based on this detection signal, an air volume adjustment mechanism installed in the exhaust fan is controlled to adjust the exhaust air volume.

Therefore, stable and continuous air volume control and building differential pressure maintenance are possible without being affected by external disturbances.

(Example) An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 1 denotes a building, and an outside air intake port 1a provided in this building 1 is fitted with a louver 2.
Prevents intrusion into the interior.

Inside the supply air processing device 3, there are installed a bug-type filter 4 for removing foreign substances such as dust and particulate salt from the outside air, and a heating coil 5 and a cooling coil 6 for controlling the temperature of the outside air. , the outside air after being processed by this supply air processing device 3 passes through the supply air duct 7 that connects the damper 7a, and passes through the 50
% ff 13 units (of which 1 is a spare) or 10
Air is supplied to each air-conditioned space 9 in a space with a high radiation level (a so-called contaminated area) or a space where radioactive materials are not present (a so-called clean area) using two blowers 8 with a capacity of 0% (one of them is a spare). It has become. When the air-conditioned space 9 is a contaminated area, as shown in FIG. The air is discharged outdoors from an exhaust stack 13 by an exhaust fan 12 through an exhaust duct 11 equipped with an exhaust treatment device 10.

At the outlet side of the blower 8 of the air supply duct 7, as shown in FIG. 1, an aero-eye type air volume detector 20a is provided.

20b and a supply air thermometer 21 are provided respectively, and the wind g
Together with the i-adjuster 22, it constitutes an air volume control means.

On the other hand, a suction vane 23 is provided at the suction port of the exhaust fan 12, as shown in FIG. 1, and its operation unit 24 is controlled by a signal from an air volume regulator 16. And both air volume detectors 20a, 20b
The air volume of the ventilation air conditioning equipment is controlled by controlling the suction vane 23 based on the supply air volume signal from the air supply system, and the building negative pressure is set by maintaining the initial opening of the suction vane 23 at a negative or positive level. It is now possible to do so.

Next, the operation of this embodiment will be explained.

The air volume of the ventilation air conditioning system is controlled by the air volume detector 20a.

This is done by detecting the supply air flow rate at 20b and controlling the suction vane 23 based on the detection signal. Further, the building differential pressure is set by maintaining the building at negative pressure with the initial opening degree of the suction vane 23.

As shown in the flow diagram related to air volume control shown in Figure 2, regarding filter clogging, which will cause future air volume fluctuations,
The suction vane 23 adjusts the flow rate and maintains the pressure inside the building.

That is, when the resistance of the air supply duct 7 increases due to clogging of the bug type 4, etc., the system air volume decreases. This decrease in system air volume is detected by the air volume detector 20a.

20b, and the opening degree of the suction vane 23 is adjusted in the opening direction based on this detection signal.

As a result, the characteristic curve of the exhaust fan 12 changes, and the increased resistance of the air supply system is compensated for by the increased capacity of the exhaust fan 12, so that the system air volume is controlled to be constant. At this time, since the negative pressure inside the building is higher than the initial state, it becomes more reliable in terms of preventing leakage of contaminated air to the outside of the building.

Note that even when the resistance of the exhaust system duct increases due to clogging of the filters 10a and 10b on the exhaust side, the suction vane 23 moves further in the opening direction as described above, and the system air volume is controlled to be constant.

By the way, the air volume detector 20a is an aero eye type.

In an air flow meter that converts pressure into air volume, such as 20b, the air volume indication value fluctuates with changes in air temperature (air specific weight γ). Therefore, the volumetric flow ff1 (TIt/h
) is constant, if the air specific weight (γ) changes,
The suction vane 23 is controlled as the air volume instruction value fluctuates, resulting in unstable air volume control.

Therefore, in this embodiment, the supply air temperature is detected by the supply air thermometer 21 installed in the supply air duct 7, and the air supply temperature is adjusted to the standard air condition (γ-162) so that the wind m indication value does not change due to the supply air temperature. The flow rate temperature is corrected using the following equation (1).

Y: Flow rate signal after correction It is necessary to maintain the system air volume and building differential pressure, and by performing this temperature correction,
It becomes possible to remove disturbances in air volume control and perform constant air volume control.

Note that since the relationship between the air pressure weight (γ) and the supply air temperature has a substantially linear correlation as shown in the table below, there is no problem in correcting the flow rate based on the supply air temperature.

〔Effect of the invention〕

As explained above, the present invention provides an air flow control means having at least an air volume detector and an air volume regulator on the discharge side of the air blower, and an air volume control mechanism controlled by the air volume control means on the exhaust fan. Therefore, stable air volume control and building differential pressure maintenance can be performed without being affected by disturbances in air volume control, such as air volume ranges due to filter clogging.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram of a ventilation air conditioning system in a nuclear power plant showing an embodiment of the present invention, Fig. 2 is a flow diagram related to air volume control, and Fig. 3 is a diagram showing a conventional ventilation air conditioning system in a nuclear power plant. 4 is a detailed diagram of the ventilation air conditioning system in the conventional device, and FIG. 5 is a detailed diagram of the surroundings of the air supply processing device in FIG. 4. 3... Air supply processing device, 4.10a... Bag type filter, 7... Air supply duct, 8... Air blower, 9...
- Air conditioned space, 10... Exhaust treatment device, 10b... High performance particle filter, 11... Exhaust duct, 20a, 2
0b... Air volume detector, 21... Supply air temperature meter, 22.
...Air volume regulator, 23...Suction vane, 24.
...Operation unit.

Claims (1)

[Claims] 1. In a ventilation air conditioner in a nuclear power plant, in which outside air from which foreign matter has been removed by a filter is sent to an air-conditioned space by a blower, and the air in the air-conditioned space is discharged by an exhaust fan, the blower Ventilation in a nuclear power plant, characterized in that an air volume control means having at least an air volume detector and an air volume regulator is provided on the discharge side of the ventilator, and an air volume control mechanism controlled by the air volume control means is provided on the exhaust fan. Air conditioner. 2. The air volume control means has a flow rate temperature correction mechanism that corrects the air volume according to the outside air temperature and maintains the air volume to the air conditioned space at a constant level. Ventilation and air conditioning equipment in the described nuclear power plant.