Abstract: ANALYSIS OF GROSS BETA ACTIVITY IN THE TRPO PROCESSLiang Junfu Liu Xiuqin Guo Yifei(Institute of Nuclear Energy Technology,Tsinghua University, P.O.Box 1021,Beijing 102201)ABSTRACTAnalysis of gross beta activity in the TRPO process for treating high level liquid waste is studied.The gross beta activity in aqueous or organic phase samples are determined by liquid scintillation analyzer.Interference with determination of α and γ to β is discriminated.β nuclides are divided into four groups based on β maximum energy.Equivalent efficiency and weigh factor of each group are analyzed by liquid scintillation analyzer and Ge(Li) γ spectrometer.Gross β activities of the samples are calculated by equivalent efficiency method.The method is applied to analysis of gross β activity in the TRPO process with satisfactory results.Key words Gross beta activity Liquid scintillation counting High level liquid waste Equivalent efficiency method