【作者】 黄宪果； 夏文友； 涂俊； 苏容波； 吴中义；

【Author】 HUANG Xian-guo;XIA Wen-you;TU Jun;SU Rong-bo;WU Zhong-yi;China Academy of Engineering Physics;

【机构】 四川省绵阳市中国工程物理研究院核物理与化学研究所；

【摘要】 为了实现核设施退役现场α气溶胶的实时连续测量,开展了分粒度连续取样技术和核素化天然本底跟踪补偿技术研究。通过对氡钍子体气溶胶和人工放射性核素铀、²⁴¹Am气溶胶的粒径分布研究,确定了分粒度取样的切割粒径为1μm,建立了分粒度连续取样技术,实现了在气溶胶连续取样过程中钚气溶胶与天然放射性氡钍子体气溶胶的分离取样和实时连续测量。通过实验研究,建立了核素化天然本底跟踪补偿技术,实现了在钚气溶胶连续测量过程中天然本底的α能谱向前拖尾部分对钚能峰的影响的自动跟踪补偿,使用该方法对天然本底进行扣除,对钚道的扣除率大于90%。使用分粒度连续取样技术和核素化天然本底跟踪补偿技术建立的α气溶胶实时连续测量系统,当监测时间为25min,氡钍子体浓度为100Bq·m^-3时,对钚气溶胶浓度连续测量的探测灵敏度为0.02Bq·m^-3。更多还原

【Abstract】 To conduct continuous monitoring of α aerosols in the decommissioning site,we researched on the differentiated particle size sampling technology and nuclide natural background correction technology.According to the different particle size distribution of radon thorium progeny aerosols,U aerosols and Am aerosols,the cutting particle size of sampling system was determined to be 1 μm.We also studied on the separation efficiency of the sampling system.Using the sampling system,we separated Pu aerosols with radon thorium progeny aerosols successfully..What’s more,the method of nuclide natural background correction was determined,The correction efficiency is greater than 90%.An α aerosols continuous monitoring system was set up using the two technologies mentioned above.The detection sensitivity for Pu aerosols in 25 minute is 0.02 Bq.m^-3 when the concentration of radon thorium progeny is 100 Bq.m^-3.更多还原