METHOD FOR NPP LIQUID WASTE PROCESSING WITH BORON CONTROL Russian patent published in 2018 - IPC G21F9/06 G21F9/20 

FIELD: chemistry.

SUBSTANCE: method for nuclear power plants liquid waste processing with boron control containing sodium and potassium salts involves calcium nitrate introduction into a borate solution with precipitation of calcium borate and its separation from the mother liquor, electrodialysis using an electrodialyzer with cation exchange and anion exchange membranes, preparation of boric acid and solution sodium hydroxide and potassium hydroxide. The initial borate solution as sodium and potassium salts contains their nitrates and sulfates. Calcium nitrate is introduced into the initial borate solution to obtain a collective borate and calcium sulphate precipitate. Boric acid is produced by treatment of a collective borate and calcium sulfate precipitate with a nitric acidsolution, separating the calcium sulphate precipitate from the calcium borate solution. The calcium borate solution is treated with nitric acid to form a boric acid precipitate and a calcium nitrate solution. The boric acid precipitate is separated and dried. The mother liquor is subjected to electrodialysis to produce solutions of nitric acid and sodium and potassium hydroxides.

EFFECT: invention allows to reduce power consumption of the method and reduce the amount of harmful waste to be disposed.

9 cl, 4 ex