Nanofiltration Purification of Liquid Radioactive Waste

Abstract

The paper presents the results of testing the purification of real liquid radioactive waste from radionuclides, bottom residues of the Kola and Beloyarsk nuclear power plants (NPP), as well as low-level wastewater from the radiochemical building of the Institute of Physical Chemistry and Electrochemistry RAS (IPCE RAS) using the method of nanofiltration (NF) using a polymer membrane manufactured by the Russian company “RM Nanotech.” It has been shown that in the case of single-stage NF purification of bottoms of the Kola NPP, the coefficient of purification from ⁶⁰Co is 2.8, while no purification from ¹³⁷Cs practically occurs. When cleaning the bottom residues of the Beloyarsk NPP from ⁶⁰Co using a five-stage scheme, a coefficient of purification from ⁶⁰Co equal to 388 was obtained. The combination of nanofiltration purification and selective sorption of cesium on the ferrocyanide sorbent Temoksid-35 makes it possible to obtain a dry salt residue that is not related to radioactive waste. When using the method of nanofiltration for the treatment of low-level wastewater of the Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, the degree of purification was, %: ¹³⁷Сs ~ 75; ⁹⁰Sr ~ 91; ²⁴¹Am ~ 99.5; ¹⁵²Eu ~ 91; ²³⁹Pu ~ 99.5.