PIG sampling and monitoring system and method

Abstract

The invention discloses a PIG sampling and monitoring system and a method, comprising a sampling loop unit and a radioactivity measurement analysis control unit. The sampling loop unit comprises an aerosol accumulation sampling subunit and a radioactive gas accumulation sampling subunit; the aerosol accumulation sampling subunit comprises a filter; the radioactive gas accumulation sampling subunit comprises a gas accumulation sampling device and a molecular filtering film; the radioactive measurement analysis control unit comprises an HPGe detector, an energy spectrum analysis meter and a computer. The HPGe detector performs measurement on the radioactivity of the above subset units at the same time; the energy spectrum analysis meter processes the measurement information and gives out the radioactivity energy spectrum information; the radioactivity energy spectrum information and the flow control information of the sampling loop unit are transmitted to the computer for processing to obtain activity concentration of all nuclides in the airborne fluid. The invention realizes the accumulated sampling measurement on the PIG in the airborne fluid, improves the accuracy of radioactivity nuclide measurement in PIG, and has better practicability.

Description

technical field [0001] The invention relates to the technical field of radionuclide monitoring, in particular to a PIG sampling and monitoring system and method. Background technique [0002] Aerosol (P), iodine (I) and inert gas (G) are collectively referred to as PIG. The radionuclides contained in PIG are divided into natural radionuclides and artificial radionuclides. For nuclear power plants, artificial radionuclides are produced from the fission of fuel elements in the reactor and the activation of neutrons on the materials they contact; when the fuel elements are damaged and the primary loop leaks, artificial radioactive substances may enter the reactor hall and related ventilation loops, these Artificial radioactive substances can be dispersed in the reactor hall and ventilation circuits in the form of aerosols and gases (wherein radioactive iodine exists in both aerosol and gas forms), the ventilation circuits are treated and purified and discharged to the environm...

AI Technical Summary

Problems solved by technology

[0003] The disadvantage of the traditional PIG monitoring scheme is that part of the molecular iodine in the aerosol sample is adsorbed, and part of the inert gas in the iodine sample is adsorbed, and the sampling representativeness is poor.

Since the monitored data has no nuclide identification ability, the aerosol monitoring data confuses the measurement data of natural radionuclide and molecular iodine at the same time, and the measured data is too large; in the iodine measurement data, part of the molecular iodine is absorbed by the aerosol , the measured data is relatively small, but the iodine absorber has adsorption capacity for inert gases, and the measured data is relatively large. Based on these conditions, it is impossible to judge whether the measured data of radioactive iodine is too large or too small; for inert gases, the measured data Too small, and often can not obtain data (measured data is less than the lower limit of detection)

[0004] Due to the limitations of the traditional PIG monitoring scheme, if the measurement data is abnormal, the on-site sampling laboratory is required to analyze and measure, which loses the real-time monitoring and increases the workload and collective dose.

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