Authors:P. Ravi, M. Iyer, S. Sahasrabudhe, M. Subramanian, and S. Somasundaram
Methods have been developed for the routine analysis of129I in effluents of fuel reprocessing plants using 29.4 keV xenon X-rays. Direct counting methods have been standardized in liquid medium as well as in ion-exchange resin medium. A low energy photon spectrometry Ge detector system and a well-type NaI/Tl/ detector are used for direct counting. Attenuation of xenon X-rays in liquid medium as well as in ion-exchange resin medium have been studied. Sample size is optimized by studying the self attenuation of xenon X-rays in the sample. Activity as low as 1 Bq could be detected with an accuracy of 11% and 30% using LEPS and NaI/Tl/counting systems, respectively.