Low-Waste Process for Chemical Decontamination of Primary Circuits of Water-Cooled Nuclear Power Installations Using Ion-Exchange Methods for Treatment of Decontaminating Solutions

The possibilities of improving the efficiency of "low-concentration" processes for chemical decontamination of primary circuits of water-cooled nuclear power installations are examined. Laboratory experiments demonstrated the advantages of chemical dissolution of radioactive deposits of the circuits, combined with sorption treatment of the decontaminating solutions. The influence of equilibrium pH of solutions on the volumetric distribution coefficients of Fe(II), Fe(III), Co(II), and Cr(III) ions between decontaminating solutions based on complexing acids and modified AV-17-8 chS strongly basic anion exchanger was studied. The main characteristics of processes involving sorption on the anion exchanger in the EDTA form from solutions containing ethylenediaminetetraacetic, oxalic, and citric acids and on the anion exchanger in the HEDP form from solutions containing 1-hydroxyethane-1,1-diphosphonic acid, hydrazine, and ammonia are compared.