An open-loop method and device for measuring radon exhalation rate of emanation medium

Abstract

The invention discloses a method and device for measuring the emanation medium radon exhalation rate in an open-loop mode. According to the method, the measurement of the radon exhalation rate is carried out by using the device. The device comprises a radon measuring instrument and a test column used for containing a to-be-tested emanation medium, a gas collecting cover is arranged above the testcolumn, the gas inlet of the radon measuring instrument is communicated with the gas collecting cover through an air pipe, the gas outlet of the radon measuring instrument is communicated with an external environment, a hole communicated with the external environment is formed in the upper surface of the gas collecting cover, a gas pressure equalizing chamber is arranged below the test column, thegas pressure equalizing chamber is connected with a gas pump through the gas pipe, and a flow regulator is arranged on the gas pipe between the gas pressure equalizing chamber and the gas pump. The method has the advantages that the free diffusion of the radon on the surface of the medium is considered, and the influence of the seepage effect is also considered. In addition, the device can accurately measure the radon exhalation rate of the surface of the medium in a short time.

Description

technical field [0001] The invention relates to an open-loop method and device for measuring radon exhalation rate of emanation medium, in particular to a seepage device for generating controllable flow rate in particle accumulation type emanation medium and a method for determining radon exhalation rate under the action of seepage-diffusion The method belongs to the technical field of nuclear radiation measurement. Background technique [0002] Radon is an inert radioactive gas, which is colorless and odorless, and widely exists in rocks, soil and groundwater. The World Health Organization (WHO) lists radon as 19 major environmental carcinogens. Radon release rate is a physical quantity to evaluate the ability of emanating medium to release radon. Reasonable and scientific measurement of radon release rate and release law is a research focus of scholars at home and abroad. [0003] Radon exhalation rate is a parameter that expresses the rate of radon release from the surfa...

AI Technical Summary

Problems solved by technology

When there is seepage inside the medium, the closed-loop radon measurement method will inhibit the radon gas from entering the collection chamber, thereby affecting the accuracy of the measurement results; while the open-loop radon measurement avoids the obstruction of the collection chamber to the seepage gas, However, it is impossible to analyze the amount of radon exhalation at different seepage velocities, and it is difficult to understand the influence of the internal seepage velocity of the medium on the radon exhalation rate

[0004] The Chinese patent literature discloses a patent application for an "open-loop method and measuring device for measuring radon exhalation rate" (application number: CN201010129774.6). Due to the small decay constant of radon, it is recommended to ignore

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