Design of a spent resin monitoring and sampling system

This paper reports that the sampling of radioactive spent resins presents two challenges: determining when adequate mixing of recirculating resin has been achieved and minimizing personnel radiation exposure while drawing high-activity samples. A computer-controlled, spent resin monitoring and sampling system has been designed to meet these challenges. The system monitors the level and/or energy of the radiation emitted from the resin recirculation line, determines when the resin mixture is homogenous, and activates resin aliquot collection by an automatic sampling valve. The design has been tested with a laboratory mock-up and is ready for installation and full-scale testing in a power plant