JPH02675Y2 - - Google Patents

Description

[Detailed description of the invention] This invention provides a method for measuring radioactivity released in wastewater discharged from nuclear facilities using a wastewater monitor.
The present invention relates to a natural radioactivity removal device that removes natural radioactivity mixed in a gaseous state in the waste water to improve measurement accuracy of the emitted radioactivity.

Conventionally, radiation water monitors are equipped with a lead shield or the like in the detection section to avoid the influence of natural radioactivity from the atmosphere. However, the natural radioactivity contained in wastewater, such as radon and thoron, had no choice but to wait for natural decay. However, in order to accurately measure minute amounts of emitted radioactivity in wastewater, it is necessary to eliminate the influence of natural radioactivity, which is caused by rainwater mixed into wastewater due to weather conditions, on the measurement accuracy of wastewater monitors. There must be.

In view of the above-mentioned points, it is an object of the present invention to provide a natural radioactivity removal device that eliminates the problems of the prior art and can improve its measurement accuracy.

According to the present invention, such a purpose is achieved by a tank;
A spray pipe provided in the tank and having a spray nozzle for ejecting waste water in the form of a spray; and a blower provided in the tank for bringing air into contact with the atomized waste water ejected from the spray nozzle; This is achieved by removing the natural radioactivity mixed in with the air from the wastewater by the air.

Hereinafter, a preferred embodiment of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 shows a basic configuration diagram of an embodiment of the present invention. In the figure, a natural radioactivity removal device 1 includes a tank 2, a spray pipe 3, and a blower (fan) 4 that brings air into contact with the sprayed wastewater ejected from the spray pipe 3.
It consists of Drainage from the nuclear facility is discharged through a drain 5. The pump 6 collects this waste water through a waste water sampling pipe 7, a stop valve 8, and a flow meter 9.
After that, it is supplied to the natural radioactivity removal device 1. After passing through the natural radioactivity removal device 1, the wastewater is supplied to a wastewater monitor (radioactivity measuring device) 10, measured, and then returned to the drain 5. Reference numeral 11 indicates a drainage monitor display. In the natural radioactivity removal device 1, the tank 2 consists of a casing 12 and a lid part 13, and the spray pipe 3 is installed in the casing 12 to eject wastewater in the form of a spray. The blower 4 is installed in the lid part 13 and brings air into contact with the sprayed waste water. Natural radioactivity mixed into wastewater, such as radon and thoron, exists in the wastewater in a gaseous state, so by atomizing the wastewater and increasing its contact area with the air, this air can be absorbed. This allows natural radioactivity to escape and be removed from wastewater. The wastewater from which natural radioactivity has been removed in this way is discharged from the bottom of the housing 12, and the discharged radioactivity is measured by the wastewater monitor 10.

Note that the blower 4 exhausts the air in the tank 2,
Although external air may be sucked in from between the casing 12 and the lid 13, air may be introduced into the tank 2 and air may be discharged to the outside from between the casing 12 and the lid 13.
Note that the radioactivity measurement device is mainly composed of the natural radioactivity removal device 1 and the waste water monitor 10.

Next, FIG. 2 shows a schematic configuration diagram of one embodiment of the present invention shown in FIG. 1, where A is a front view thereof, B is a plan sectional view thereof, and C is a side view thereof. In the figure, parts having the same functions as those in FIG. 1 are given the same reference numerals. One end of the spray pipe 3 is connected to the waste water sampling pipe 7 via a side wall of the housing 12 by a flange 21, and the other end is fixed to the other side wall of the housing 12 by a flange 22. The spray pipe 3 includes a main spray pipe 14 whose inner diameter is about the same as that of the wastewater sampling pipe 7 to reduce resistance inside the pipe, and in this embodiment, L-shaped branch pipes 15 arranged in four pairs of two oppositely. , and a connecting fitting 23 that integrally connects the spray branch pipe 15 to the spray main pipe 14. This spray branch pipe 15 is provided with a large number of spray nozzles 16 that uniformly spray waste water into the tank 2, each with an appropriate spray angle upward.

In addition, a blower mounting pipe 17 is provided at the head of the lid portion 13.
is integrally provided, and the blower 4 is installed in the side opening of the blower attachment pipe 17. In addition, case 1
An inclined plate 18 is provided at the bottom of the spray nozzle 16 and has a gentle inclination angle that descends in the longitudinal direction. The water is supplied to a drainage monitor 10 shown in FIG. Furthermore, one end of the cleaning water supply pipe 20 is connected to the upper end of the housing 12,
Washing water is supplied as needed to wash the inside of the tank 2, and then is discharged to the outside through a drainage outlet pipe 19. Furthermore, when the spray pipe 3 is contaminated by drainage and the spray condition of the spray nozzle 16 becomes particularly poor, it can be removed from the housing 12 and cleaned with washing water or air. Such a natural radioactivity removal device 1 sprays wastewater from the spray nozzle 16 in the form of a uniform mist, and uses the blower 4 that sucks out the air in the tank 2 to remove the wastewater from between the casing 12 and the lid 13. Sufficient contact can be made between the inhaled outside air and the atomized waste water. As the contact area between the wastewater and the outside air has increased in this way, the natural radioactivity in the gaseous state mixed in the wastewater is mixed into the outside air and is discharged to the outside by the blower 4, so that the natural radioactivity is removed from the wastewater. Ru.

As described above, according to the present invention, there is provided a tank, a spray pipe provided in the tank and having a spray nozzle for spouting wastewater in the form of a spray, and a spray pipe provided in the tank and having an air flow to the atomized wastewater. By being equipped with a blower that brings the wastewater into contact with the air, the contact area between the wastewater and the air increases, and gaseous natural radioactivity in the wastewater is eliminated together with the air. The trace amount of released radioactivity in the sample has the effect of improving measurement accuracy without being affected by natural radioactivity.

[Brief explanation of the drawing]

Figure 1 is a diagram of the principle configuration of an embodiment of the present invention, Figure 2
The figures show a schematic configuration diagram of one embodiment of the present invention in FIG. 1, where A is a front view thereof, B is a plan view thereof, and C
is its side view. 1: Natural radioactivity removal device, 2: Tank, 3: Spray pipe, 4: Blower, 10: Drainage monitor, 16: Spray nozzle.

Claims (1)

[Scope of utility model registration request] A tank, a spray pipe provided in the tank and having a spray nozzle for spraying wastewater discharged from a nuclear facility, and bringing air into contact with the spray wastewater provided in the tank and sprayed from the spray nozzle. What is claimed is: 1. A natural radioactivity removal device, comprising: a blower, wherein natural radioactivity mixed in the waste water in a gaseous state is removed from the waste water using the air.