METHOD FOR CLEANING RADIOACTIVE AQUEOUS SOLUTIONS FROM RADIONUCLIDES Russian patent published in 2003 - IPC

FIELD: decontamination of aqueous radioactive solutions. SUBSTANCE: radioactive aqueous solutions are decontaminated at pH of minimum 4 with sorbent such as powdered amorphous titanium phosphate having grain size of minimum 10 mcm. Decontamination process is conducted in steps under counter- current conditions, solution and sorbent being mixed up for time sufficient to ensure equilibrium state between solution and sorbent during each decontamination step. Number of steps N depends on desired degree of cleaning from radionuclides with respect to gamma- and beta-activity according to equation N = (lnC_source-lnC_end)/(lnK_d+lnα), where C_source is gamma- or beta-activity of radionuclides in source solution; C_end is admissible gamma- or beta- activity of radionuclides in end solution; α is mass proportion of sorbent and solution in each step; K_d is radionuclide distribution factor with respect to gamma- or beta-activity. Radionuclide-containing sorbent is separated by filtering or centrifuging and disposed to burial ground. EFFECT: enhanced effectiveness of decontaminating liquid radioactive wastes. 8 cl, 1 tbl