Life cycle of ion exchangers in nuclear industry: Application and management of spent exchangers

Abstract

Ion exchange technique is one of the widely applied conventional treatment options in nuclear industry, which is used to reduce the volume of aqueous radioactive waste streams, to separate isotopes and in decontamination operations. After being exhausted, spent exchangers are considered as radioactive waste and consequently they must be safely managed to minimize their environmental impacts. Exchangers' selection and operating conditions optimization are affected by the waste and exchanger characteristics. In this chapter, the life cycle of the exchange materials will be traced starting from material preparation to disposal. Within this context, sources of radioactive wastes and their important characteristics will be introduced. Exchanger preparation and characterization methods will be overviewed. Chemical, mechanical, and radiological design criteria that affect performances of the process will be summarized. Treatment and immobilization options of spent ion exchangers will be overviewed and methods to assess immobilization sustainability will be highlighted.