双通道人工放射性气溶胶监测系统设计  

Design of dual channel artificial radioactive aerosol monitoring system

作　　者：曾国强[1] 赖茂林[1] 顾民[1] 卿松[1] 杨坤 谷懿[1] 夏源[1] 葛良全[1] 肖明 

机构地区：[1]成都理工大学四川省地学核技术重点实验室,成都610059 [2]中广核久源(成都)科技有限公司,成都610200

出　　处：《核技术》2017年第5期37-43,共7页Nuclear Techniques

基　　金：国家自然科学基金(No.41474159);国家863计划项目(No.2012AA061803);四川省科技厅青年基金项目(No.2015JQ0035)资助~~

摘　　要：人工放射性气溶胶的监测环境较为复杂,有时甚至要在地下洞库、坑道或地下核设施测量,其环境中氡及其子体产物的浓度高达10~3-10~4 Bq·m^(-3)。在高氡钍环境下,氡钍能峰拖尾导致其放射性计数影响了人工气溶胶道址计数,进而影响人工放射性气溶胶的探测下限。本文研制了一种适合在高氡环境下工作的常压、真空双通道人工气溶胶监测仪。虽然常压测量通道测量准确度较差,但响应速度快,可以弥补真空测量通道测量准确但响应速度慢的缺点。本仪器对大气环境中钚、铀气溶胶检测的响应时间快,在有人工核素泄露的情况下最快30 min内可以得到测量结果,理论探测下限可达到10^(-4)-10^(-3) Bq·m^(-3),可验证探测下限为铀0.1 Bq·m-3、钚0.02 Bq·m^(-3),适用于各类需要对人工核素进行无人监测的高氡环境场所。Background： The environments for monitoring artificial radioactive aerosol are often complex, as sometimes it could even be in underground caverns, tunnels or underground nuclear facilities, of which the concentration of both radon and its radioactive products would be up to 10^3-10^4 Bq·m^-3. However, under high radon condition, the tailing phenomenon of radon and thorium peaks could interfere with radioactive counts and the artificial aerosol counts, thus affecting the detection limit of radioactive aerosol. Purpose： This study aims to design a special normal-pressured artificial aerosol monitoring equipment, which can operate well under the high radon environment. Methods： Dual-channel synchro measurement was employed to combine high accuracy of the vacuum channel and the fast response of the normal pressure channel. Results： Implemented aerosol monitoring system can respond rapidly to plutonium and uranium aerosol in atmospheric environment, and in the case of artificial radionuclide leakage, the fastest measurement results can be obtained in 30 min. In general, the theoretical detection limit can reach 10^4-10^-3 Bq·m^-3, and the verifiable detection limit of uranium and plutonium are 0.1 Bq.m3 and 0.02 Bq·m^3, respectively. Conclusion： This design can be applied to a variety of high radon environments which require unmanned monitoring for artificial nuclear.

关 键 词：高氡钍背景 人工放射性气溶胶 探测下限 真空测量 

分 类 号：TL84[核科学技术—核技术及应用]