Research progress on treatment technology of silicon-containing RCS water with high content boron

At present, there is a common problem of significant increase in silicon content in the primary circuit (RCS) of domestic nuclear power plants. In order to seek reasonable methods and ideas to solve this problem, the main sources of silicon in RCS water were systematically investigated, and the treatment methods for ordinary silicon-containing water and the silicon treatment methods currently applied in RCS of nuclear power plants were summarized. The study showed that the silicon in RCS mainly was from fuel racks made of Boraflex materials and RCS fiberglass filter cartridges. There were many treatment technologies applied to ordinary silicon-containing water, but due to the high boron content of RCS water, only resin and membrane methods had been applied and practiced in RCS of nuclear power plants. Among them, ion exchange resin method could be used in the form of mobile devices for emergency treatment due to its high cost. NF and RO were typical membrane separation processes used for RCS silicon removal, but the recovery rate of boron in these processes was low. New technologies needed to be developed to improve the recovery rate of boron.