A PROCEDURE FOR THE CONTINUOUS CONTROL OF THE RETENTION PROPERTIES OFGAS ADSORBER SYSTEMS

The retention of the radioactive noble gases takes place on the charco al adsorber by dynamic adsorption, meanwhile their radioactivity decre ase according to their half-life-times. For the optimal operation of t he adsorber units the on-line control and analysis of the retention pr operties would be required. Therefore a procedure has been developed f or the determination of the retention times and the dynamic adsorption coefficients for the specific noble gas isotopes. The method is based on the continuous analysis of the in- and out-flow of the adsorber sy stem by gamma-ray spectroscopy using semiconductor detectors. After th e successful laboratory test, the procedure was installed and the rete ntion properties of a charcoal based radioactive gas adsorber system w ere determined. For the evaluation of the data, a theoretical model wa s developed, which was used for the calculation of the dynamic retenti on coefficients of the noble gas isotopes.