Radioactive air on-line monitoring device

Abstract

A radioactive air on-line monitoring device is provided with a detection chamber, air in a monitored environment is extracted, compressed and guided into the detection chamber, so that the air pressure in the detection chamber is higher, the air density is larger, a detection device (including a detector) used for detecting the radioactive level in the air is arranged in the detection chamber, the air is compressed to a proper compression ratio, so that the high-dose air sample capable of reflecting the real radiation level of a monitoring object (the measured atmosphere) is obtained. The air density in the detection chamber is larger, and the concentration of radioactive substances in the air is higher, so that higher detection energy resolution and detection sensitivity are achieved, the detectable lower limit can be improved, and the detection accuracy is improved. The purpose can be achieved without configuring a high-sensitivity detector (such as HPGe), that is to say, high detection energy resolution and detection sensitivity are achieved under non-laboratory conditions.

Description

technical field [0001] The invention relates to the technical field of air radiation detection. Background technique [0002] Due to natural and man-made reasons, there are radioactive substances in the atmosphere, and the radioactive substances in the atmosphere exist in the form of gas molecules, solid particles, and aerosols. The level of radioactivity in the natural atmosphere is generally at a safe level, but in some specific areas, such as around nuclear facilities, if the radioactivity level in the atmosphere exceeds a certain dose value if it is not properly managed or handled, radioactive environmental pollution will be formed, so specific areas need to be polluted. Airborne radioactivity levels are monitored. [0003] In the prior art, the following three methods are usually used to monitor air radioactivity levels: [0004] 1. Offline detection. Radioactive solid particles and aerosols in the air are enriched through filter paper or other media to form test sam...

AI Technical Summary

Problems solved by technology

There are the following problems: (1) filter paper can only enrich radioactive solid particles and aerosols, but cannot collect gas molecules containing radionuclides. In the presence of radioactive gases, the real radioactive level of the measured atmosphere cannot be obtained

For high-energy particle accelerators, the proportion of gas molecules in the activation products is relatively high, and this method has serious defects; (2) it cannot be analyzed in real time, because of the influence of transport attenuation, for short-lived nuclides, the off-line detection results have serious deviations, not even detectable at all

(3) The response time is long, which is not conducive to the early detection of problems or accidents and the real-time identification of emergency states

There are the following problems: (1) Affected by the natural background, the radioactive air nuclide γ all-energy peak is annihilated in the natural background. Monitoring in the natural environment can only give the converted total count after deducting the background contribution, and cannot measure (2) Under normal circumstances, the directly detected radioactive atmosphere belongs to the trace sample, which is affected by the inherent resolution, and the radioactive atmosphere that has not been enriched is detected , it is necessary to configure high-sensitivity detectors (such as HPGe, high-purity germanium detectors). regional use

There are the following problems: (1) Affected by the natural background, only the total count can be given, the energy spectrum cannot be measured, and the type of nuclide and its corresponding activity concentration cannot be distinguished; (2) The radioactive air in the form of gas molecules , because the filter paper cannot be enriched, the contribution of this part is not included in the enriched sample, and the detection data cannot reflect the real air radioactivity level; (3) The installation position is fixed, and multiple sets of devices are required for different positions, and there is no activity The inspection function is not conducive to the emergency handling of nuclear accidents

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