JPS61148395A - Emergency gas treater - 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 (Technical Field of the Invention) The present invention discharges air inside a nuclear reactor building through a filter train in the event of an accident, removes radioactive substances from the air, and maintains negative pressure inside the reactor building. The present invention relates to an emergency gas treatment device that prevents radioactive materials from leaking to the outside.

[Technical background of the invention]

In general, in the event of an accident at nuclear power facilities such as nuclear power plants, the air inside the reactor building is passed through a filter and then exhausted, allowing air that may contain radioactive materials to be released to the outside. It prevents In order to prevent such leakage of radioactive materials to the outside, existing nuclear power plants are equipped with an emergency gas treatment system (SGTS: 5tandb) as shown in Figures 5 and 6.
y Gas Treatment System)
is installed.

FIG. 5 shows the configuration when the 5GTS is installed in the reactor building 1, and the conventional emergency gas geostation device will be described below based on this diagram. This 5GTS has air intake piping 2. Isolation valve 3.6. Exhaust fan 4. and a filter train 5, two sets each of 100% capacity filter trains 5 and exhaust fans 4 are installed, one of which is used as a spare. Inside each filter train 5, in order from the suction side, there is a moisture removal bag [5a, if air heater 5b, pre-filter 5c, high-performance particle filter 5d, charcoal filter 5e,
A high performance particle filter 5f is housed.

The moisture removal device 5a and the electric heater 5b include an iodine charcoal filter 5e and a high-performance particle filter 5d.
, 5f to prevent a decrease in efficiency due to moisture. That is, the air after passing through the moisture removal device 5a is saturated air that does not contain water droplets and has a maximum relative humidity of 100%, so the electric heater 5b uses the moisture removal device so that the relative humidity is 70% or less. The air passing through 5a is heated.

The pre-filter 5C is a high-performance particle filter 5d.

This is provided to protect the efficiency from decreasing due to clogging of the 5f. The high-performance particle filters 5d and 5f are used to purify the inhaled air, so the high-performance particle filter 5d on the upstream side collects minute particles from the reactor building 1, and the high-performance particle filter 5d on the downstream side collects minute particles from the reactor building 1. The filter 5f prevents carbon particles and the like from the iodine charcoal filter 5e from escaping into the atmosphere through the exhaust pipe 7.

The iodine charcoal filter 5e is for removing radioactive iodine contained in the air, and the spaces upstream and downstream of each iodine charcoal filter 5e are filled with iodine as shown in FIG. In order to prevent performance deterioration of the charcoal filter 5e due to moisture, a space heater 8 consisting of a fan 8a and an electric heater 8b is installed.

Therefore, in the event of an accident, the air inside the reactor building 1 is passed through the air suction pipe 2 and the isolation valve 3 by the exhaust fan 4, and after removing as much radioactive material as possible in the filter train 5, it is passed through the isolation valve 6. It is designed to be released into the atmosphere from the exhaust stack 7.

Note that each filter train 5 is equipped with a temperature and pressure detection device (not shown), so that excessive temperature within the train and prevention of filter clogging can be monitored from the outside.

[Problems with background technology]

By the way, as mentioned above, such conventional emergency gas processing equipment has a two-line configuration in consideration of the case where dynamic equipment such as fans and electric heaters breaks down for some reason. It is disadvantageous in terms of cost, and in terms of maintenance, it cannot be said that maintenance and inspection can be carried out easily.

(Purpose of the Invention) The present invention was made in view of the above circumstances, and its purpose is to reliably prevent the leakage of radioactive materials in the event of a nuclear reactor accident, reduce costs, and improve maintainability and safety. The purpose of the present invention is to provide an emergency gas processing device with excellent performance.

[Summary of the invention]

In order to achieve the above object, the present invention is characterized in that a moisture removal device, an electric heater, and a space heater are arranged separately from the filter train.

(Embodiments of the Invention) Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a schematic configuration diagram of an emergency gas treatment device of the present invention corresponding to the conventional example shown in FIG. 5, and FIG. 2 is a schematic diagram of an emergency gas treatment device of the present invention corresponding to the conventional example shown in FIG. FIG. Further, FIGS. 3 and 4 are diagrams showing the configuration of a filter train organized into one series. In each figure, the same parts as in FIGS. 5 to 7 are designated by the same reference numerals.

In the apparatus of the embodiment shown in FIG. 1, two series of moisture removal devices 5a and two electric heaters 5b are provided upstream of the exhaust fan 4, and the air exiting the exhaust fan 4 is filtered into one series of filter trains. After passing through 5, it is released into the atmosphere from an exhaust pipe 7. Inside the filter train 5, in order from the suction side, there are a pre-filter 5c, a high-performance particle filter 5d, and a charcoal filter for iodine 5e.

A high-performance particle filter 5f is housed therein, and radioactive substances in the air introduced by the exhaust fan 4 are removed by an iodine charcoal filter 5e.

Next, in the apparatus of the embodiment shown in FIG. 2, the exhaust fan 4 is installed downstream of the filter train 5 in one series, but otherwise the moisture removal device @ 5
a and the electric heater 5b are arranged separately from the filter train 5.

Further, in the embodiment shown in FIGS. 1 and 2, the space heater 8 is installed outside the filter train 5 that is connected in a series as shown in FIG. 3 or 4. That is, in the case of FIG. 3, two space heaters 8 are installed outside the spaces on the upstream and downstream sides of the iodine charcoal filter 5e, and these space heaters 8 and each space are connected to piping 9, respectively. and isolation valve 10
By connecting through the air, the air in each space is recirculated and heated to lower the relative humidity. In the case of FIG. 4, the upstream and downstream sides of the iodine charcoal filter 5e are connected by a pipe 9, and an isolation valve 1 is installed in the flow path.
0 and a space heater 8 are provided, and while the emergency gas processing device is on standby, a fan 8a built in the space heater 8 moves the air in the filter train 5 upstream and downstream of the iodine charcoal filter 5e. The humidity is adjusted by passing and circulating it on the side.

According to the above configuration, when maintaining the electric heater 5b, the first
In both the embodiments shown in FIG. 2 and FIG. 2, the isolation valve 3 is closed, but since the other electric heater 5b is operable at this time, the function as an emergency gas processing device is maintained. Furthermore, when maintaining the space heater 8, the isolation valve 10 is closed, but as in the case of the electric heater 5b, the other space heater 8 is operable, so its function as an emergency gas processing device is maintained. .

In this way, in the embodiment shown in FIGS. 1 and 2,
By arranging the moisture removal device 5a, electric heater 5b, and space heater 8, which were conventionally housed in the filter train 5, separated from the filter train, the number of filter trains 5, which were conventionally required to be two, can be reduced to one. , and the cost can be reduced accordingly. In addition, in the embodiment shown in FIG. 1, air with a relative humidity of 100% containing water droplets in the reactor building 1 is removed by a moisture removal device 5a separately arranged upstream of the exhaust fan 4. Therefore, the humidity can be lowered by increasing the temperature of the processed air due to the compression work of the fan, and the capacity of the electric heater 5b can also be reduced.

〔Effect of the invention〕

As explained above, according to the present invention, the moisture removal device, electric heater, and space heater are arranged separately from the filter train, so the number of filter trains that conventionally required two can be reduced to one, improving maintainability. Moreover, it is possible to reduce costs without compromising safety. Furthermore, by integrating the filter train into one series, it is possible to obtain effects such as reducing the installation space and halving the time and effort required for testing and inspecting the filters.

[Brief explanation of the drawing]

FIGS. 1 and 2 are schematic configuration diagrams of an emergency gas treatment system showing one embodiment of the present invention, and FIGS. 3 and 4 are filter trains arranged in one series, reactor building, two
...Air suction piping, 3.6... Isolation valve, 4... Exhaust fan, 5... Filter train, 5a... Decrease removal device, 5b... Electric heater, 5c... Pre-filter, 5d, 5f...High performance particle filter, 5e...
- Iodine filter, 7...exhaust stack, 8...space heater. Applicant's representative Patent attorney Takehiko Suzue Figure 3 Figure 4-r:, IQ-

Claims (1)

[Claims] Emergency gas treatment equipment that exhausts the air inside the reactor building through a filter train in the event of an accident, removes radioactive substances from the air, and maintains negative pressure inside the reactor building to prevent radioactive substances from leaking outside. 2. An emergency gas treatment device according to claim 1, wherein a moisture removal device, an electric heater, and a space heater are arranged separately from the filter train.