JPH02657B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a moisture extraction device for extracting moisture from air, for example, exhaust gas from a nuclear reactor facility.

In nuclear reactor facilities such as nuclear reactor power plants, it is extremely important for safety management to measure the amount of tritium contained in the exhaust gas.
The above tritium is contained in the moisture in the exhaust gas, and in order to measure the amount of tritium, it is necessary to extract the moisture in the exhaust gas.

Conventionally, in order to extract moisture from exhaust gas, the pressure of the sampled exhaust gas was increased using a pump, the relative humidity was raised, and the moisture was extracted using a dehumidifier. However, since a dehumidifier is used, the temperature cannot be lowered to below 0°C, which naturally limits the dew point conditions of the exhaust gas to be sampled. Therefore, when water in exhaust gas is continuously recovered, there is a problem that the extraction efficiency is extremely low depending on the dew point conditions (for example, when the dew point condition is 0° C. or lower).

This invention was made in view of the above points,
A highly durable moisture extraction device that can extract moisture efficiently regardless of the dew point temperature of the sampling gas, can keep the sampling gas pressure at about atmospheric pressure, has a simple structure, can be realized at low cost, and has excellent durability. The purpose is to provide

An embodiment of the present invention will be described below with reference to the drawings. In the figure, 11 is a sampling gas distribution pipe into which sampling gas is introduced from one end side, and this sampling gas distribution pipe 11
In the middle part, there is a pump 12 that sucks in the sampling gas and sends it out backwards, a first moisture extraction part 13 that extracts moisture from the sampling gas sent by this pump 12, and a part that is not extracted by this first moisture extraction part 13. a second moisture extractor 14 that extracts moisture from the sampled gas; a steam prevention valve 15;
A constant flow valve 16 and a flow meter 17 are provided in this order. Note that the pressure of the sampling gas flowing through the sampling gas distribution pipe 11 needs to be considered only for the pressure loss in the entire piping system, so a pressure of a slight pressure added to atmospheric pressure is sufficient. be.

Thus, the first water extraction section 13 is installed such that its inlet section 13a is located at a higher position than its outlet section 13b. Further, the second water extraction section 14 is installed such that its inlet section 14a is located at a lower position than its outlet section 14b. A pipe 18 for water extraction is connected to the pipe 11 near the inlet portion 14a of the second water extractor 14. A drain valve 19, which is normally closed, is provided in the middle of the pipe 18, and its end communicates with a drain tank 20. In addition, a pipe 21 is further connected to the pipe 18 on the outlet side of the drain valve 19, and this pipe 21 is provided with a pipe 21 which is connected when the pressure in the drain tank 20 becomes higher than the pressure on the upstream side of the drain valve 19. A pressure regulating valve 22 is provided to equalize the pressure.

By the way, the first moisture extraction section 13 is provided with a cooling section, and the second moisture extraction section 14 is provided with a freezing section. As this cooling and freezing means, a refrigerant pipe 2 from a refrigerator 23 is used as shown in the figure.
4 is placed in contact with the first and second moisture extraction parts 13 and 14. That is, the second moisture extractor 14 is installed upstream of the refrigerant pipe 24 (a portion close to the refrigerant outlet 23a of the refrigerator 23),
The first water extraction section 13 is installed downstream of the refrigerant pipe 24 (a portion close to the refrigerant return port 23b of the refrigerator 23 and where sufficient cooling capacity exists). As a result, the second moisture extracting section 14 can immediately freeze the moisture in the sampling gas present therein by using sufficient freezing power (approximately -40 degrees). On the other hand, the first water extraction section 13 has sufficient cooling capacity to instantly cool the sampling gas present therein to a temperature below a preset dew point temperature. Further, a heater 25 is provided in the second water extraction section 14 . This heater 25 is the second
After the moisture in the sampling gas in the moisture extracting section 14 has sufficiently frozen into ice blocks, it is activated to melt the ice blocks.

The sampling gas distribution system and the refrigerant distribution system of the refrigerator 23 described above are entirely covered with a heat insulating material. Further, the water in the drain tank 20 is sent as a sample to the monitor device 26, and the components of the water are detected.

Next, the operation of the present invention configured as described above will be explained. When the sampling gas is sucked in by the pump 12, sent through the pipe 11, and enters the first moisture extraction section 13, the sampling gas is cooled to a preset dew point temperature or lower. for example,
When the air temperature is 30°C (dew point temperature is 10°C), if the temperature of the first moisture extracting section 13 is set to be 10°C or less, the first moisture extracting section 13
Most of the water in the sampling gas is extracted. The water extracted by the first water extractor 13 flows naturally and accumulates in the pipe above the drain valve 19.

On the other hand, the sampling gas that has passed through the first water extraction section 13 (moisture still remains) is transferred to the second water extraction section 13.
The water enters the moisture extracting section 14 of. Since the sampling gas that has entered the second moisture extraction section 14 is exposed to a temperature of about -40 DEG C., the moisture in the sampling gas is immediately frozen and becomes ice blocks. After a predetermined period of time, the heater 25 provided in the second water extraction section 14 is heated to melt the ice block.
When heating the heater 25, the water vapor prevention valve 15 is closed to prevent water vapor from being included in the dry exhaust gas. The moisture generated by the melting naturally flows downward and is stored in the pipe above the drain valve 19 together with the moisture extracted by the first moisture extraction section. The sampling gas whose moisture has been frozen in the second moisture extraction section 14 becomes a dried gas and is discharged to the outside through the constant flow valve 16 and the flow meter 17.

Therefore, in order to take out the water stored in the pipe above the drain valve 19, it is sufficient to open the drain valve 19, and thereby the water as a sample can be collected in the drain tank 20.

Then, if the water stored in the drain tank 20 is analyzed by the monitor device 26, the content of desired components can be immediately detected.

In the above embodiment, the refrigeration cycle of one refrigerator is used as a means for cooling the sampling gas in the first moisture extraction section 13 and as a means for freezing the sampling gas in the second moisture extraction section 14. Although this is described above, the present invention is not limited to this, and separate cooling devices and freezing devices may be used. In addition, the present invention is not limited to the above-described embodiments, and can be implemented with various modifications without departing from the gist thereof.

As explained above, according to the present invention, the sampling gas is cooled in the first moisture extraction section to a temperature below the dew point temperature depending on the air temperature at that time, and most of the moisture is extracted there. In the water extraction section 2, the remaining water is frozen and melted to extract water, so water can be extracted efficiently regardless of the dew point temperature of the sampling gas. Since it is only necessary to consider the pressure loss of the entire piping system through which the gas passes, a pressure of a small amount added to atmospheric pressure is sufficient, and there is no need for the piping system to have a pressure-resistant structure, and it is also cost-effective. It is possible to provide a water extraction device that is also excellent in terms of durability.

[Brief explanation of drawings]

The figure is a configuration diagram of an embodiment of the present invention. 11...Pipe for sampling gas distribution, 1
3...First moisture extraction section, 14...Second moisture extraction section, 19...Drain valve, 20...Drain tank, 23...Freezer, 25...Heater.

Claims (1)

[Claims] 1 A sampling gas distribution pipe system with a sampling gas inlet at one end and an outlet for discharging the dried sampling gas after water removal at the other end, and a pipe system installed in the middle of this pipe system. a second moisture extraction section provided in the middle of the pipe system and between the first moisture extraction section and the outlet; and the second moisture extraction section. a water vapor prevention valve located on the downstream side of the sampling gas distribution pipe system, and a water vapor prevention valve provided in the sampling gas distribution pipe system to cool the moisture in the sampling gas in the first moisture extraction section to below its dew point temperature, and the second moisture extraction. means for freezing water in the sampling gas in the second water extraction part; a heater for melting the ice block in the second water extraction part formed by the means after closing the water vapor prevention valve; and the first water extraction part. A water extraction device comprising a water extraction pipe system for extracting the water extracted in the second water extraction part and the water extracted in the second water extraction part.