CN-115932938-B - Array type alpha energy spectrum measuring system

Abstract

The invention discloses an array type alpha energy spectrum measuring system, which can enrich radioactive aerosol with ultralow concentration by adopting high-flow air sampling (the extraction amount can reach 500-1000m 3 /h), can improve the detection lower limit of measurement from the magnitude of 10 ‑1 Bq/m 3 to 10 ‑3 Bq/m 3 , and expands the low-range of measurement. Compared with the traditional single-channel sampling and measuring method, the system can more uniformly enrich the aerosol with the same sampling volume on the large-area sampling filter paper, ensure that the concentration of the aerosol under the ultra-high concentration does not exceed the effective enrichment thickness of the aerosol, so that the measurement precision of the high-concentration aerosol is influenced. The upper limit of the measurement range is raised from the order of 10 3 Bq/m 3 to the order of 10 5 Bq/m 3 .

Inventors

• HOU XIN
• Hu Hengsong
• LIAO PENG
• YAO FEI
• NIU DEQING
• LIANG JIE
• WU CHUNMIN
• YUAN MINJUAN
• REN YONG
• QIAO YANG

Assignees

• 中国兵器装备集团自动化研究所有限公司

Dates

Publication Date

20260512

Application Date

20230109

Claims (6)

1. 1. An array type alpha energy spectrum measurement system, comprising: The enrichment unit is used for enriching radioactive aerosol in sampled gas onto sampling filter paper, and comprises an air sampling assembly, wherein the air sampling assembly is used for guiding the sampled gas onto the sampling filter paper, the air sampling assembly comprises a vacuum air pump and a pump control module, the pump control module is connected with the analysis unit, the air pumping quantity of the vacuum air pump is 500-1000 cubic meters per hour, and the area of the sampling filter paper is not less than 6500 square millimeters; the array type aerosol measurement unit is used for receiving the sampling filter paper and detecting different areas of the sampling filter paper through the multipath detection assembly to obtain a plurality of independent alpha energy spectrums; the analysis unit is used for synthesizing the received multiple independent alpha energy spectrums to obtain a total alpha energy spectrum, and analyzing and calculating the total alpha energy spectrum to obtain the total activity of the radioactive aerosol alpha.
2. 2. The array-type alpha energy spectrum measurement system of claim 1, wherein the detection assembly comprises a PIPS detector and a digital multi-channel analyzer connected.
3. 3. The array-type alpha energy spectrum measurement system of claim 2, wherein the effective measurement area of the PIPS detector is not less than 475 square millimeters.
4. 4. The array-type alpha energy spectrum measurement system of claim 3, wherein the detection assembly comprises 15 paths, and the total effective measurement area of the 15 paths of the detection assembly is not less than 7000 square millimeters.
5. 5. The system of claim 2, wherein the digital multi-channel analyzer is communicatively coupled to the analysis unit via a data communication module.
6. 6. The array-type alpha energy spectrum measurement system of claim 1, further comprising an automatic sample feeding unit for feeding the sampling filter paper to the array-type aerosol measurement unit.

Description

Array type alpha energy spectrum measuring system Technical Field The invention relates to the technical field of measurement methods of radioactivity of aerosol in air, in particular to an array type alpha energy spectrum measurement system for measuring radioactivity of the radioactive aerosol with low concentration or very low concentration and ultra-high concentration in the environment. Background Radioactivity measurement of aerosols is a major means of environmental radioactivity monitoring, and in 2011, the importance of low concentration aerosol measurement in the environment is strongly recognized by environmental monitoring departments in order to protect the relevant nuclear environment safety, staff and public personnel health. At present, similar commercial aerosol monitoring equipment internationally usually has the detection lower limit of 0.1-0.2Bq/m 3, but the monitoring of the diffusion of the nuclear pollution of the atmosphere environment in the peripheral countries of China is still not apprehended. The existing measurement technology mainly adopts single-channel measurement, and the most practical mode is to adopt a filter paper filtering aggregation mode to enrich the sample. And transferring the sampling filter paper to the lower part of the detector, measuring the alpha radioactivity on the filter paper, and further calculating the total alpha radioactivity in the sampling air. The prior art has two main disadvantages: 1. The detection offline can only reach the order of magnitude of 10 -1Bq/m3, and the detection offline is influenced by the measurement area and the sampling flow of the single-channel detector, so that the low-concentration or extremely-low-concentration radioactive aerosol radioactivity measurement cannot be rapidly performed. 2. The upper range limit of the measuring range is limited. The upper limit of the detection range of prior art condition devices is on the order of 10 3Bq/m3. Under the condition that the concentration of radioactive aerosol in the environment is high (the concentration of the radioactive aerosol is up to 10 5Bq/m3), a single-channel sampling and measuring method is adopted, and because the filter area of the filter paper is limited, the aerosol in the air can be quickly enriched on the filter paper collecting surface and form an over-enrichment phenomenon, so that the covering of the aerosol is thickened, and the measuring error is increased. When the mass thickness of the radioactive surface covering is greater than 10 microns, the probe cannot measure the radioactive particles generated by the bottom aerosol, and thus the accurate measurement of the high-concentration total alpha activity cannot be satisfied. Therefore, how to provide an array type α spectrum measurement system that can meet the requirement of measuring the radioactivity activity of a low-concentration or very low-concentration radioactive aerosol in the environment is a technical problem that needs to be solved by those skilled in the art. Disclosure of Invention In view of the above, the present invention provides an array type alpha spectrum measurement system for overcoming or at least partially solving the above problems. The method can meet the requirement of radioactivity measurement of low-concentration or extremely low-concentration radioactive aerosol in the environment, can widen the total activity measurement range of the aerosol alpha to 10 -3Bq/m3～105Bq/m3, and can span the wide-range measurement of 8 orders of magnitude so as to meet the monitoring requirement of environmental pollution monitoring under any condition. The invention provides the following scheme: An array type alpha energy spectrum measurement system, comprising: The enrichment unit is used for enriching the radioactive aerosol in the sampling gas onto the sampling filter paper; the array type aerosol measurement unit is used for receiving the sampling filter paper and detecting different areas of the sampling filter paper through the multipath detection assembly to obtain a plurality of independent alpha energy spectrums; the analysis unit is used for synthesizing the received multiple independent alpha energy spectrums to obtain a total alpha energy spectrum, and analyzing and calculating the total alpha energy spectrum to obtain the total activity of the radioactive aerosol alpha. Preferably, the enrichment unit comprises an air sampling assembly for directing the sample gas onto the sample filter paper. Preferably, the air sampling assembly comprises a vacuum air pump and a pump control module, and the pump control module is connected with the analysis unit. Preferably, the pumping quantity of the vacuum pump is 500-1000 cubic meters per hour. Preferably, the area of the sampling filter paper is not less than 6500 square millimeters. Preferably, the detection assembly comprises a connected PIPS detector and a digital multi-channel analyzer. Preferably, the effective measurement area of