METHOD OF DESALTING WATER Russian patent published in 1997 - IPC

FIELD: freshening of water. SUBSTANCE: method includes the following operations: treatment of initial water (naturally occurring or waste water) with an alkali reagent (alkali or earth-alkali metal hydroxide); passage of alkali-treated water through ammonium and hydrocarbonate ionites, deaeration accompanied with absorption of volatile components with water; recovery of cationite with salt concentrate and then with exhausted anionite recovery solution; preparation of salt concentrate by concentrating liquid phase obtained after heat treatment of mixture of exhausted cationite solutions and its preliminary treatment with alkali reagent; recovery of anionite with solution obtained after absorption of volatile components from water deaeration stage and heat treatment of mixture of exhausted cationite recovery solutions. As a result, total salt content in water is 1.5-1.7 times reduced, including magnesium ion content 1.75-2.0 times, sodium ion 1.4-1.6 times, and chloride ion 1.45-1.7 times reduction. Volumes of recovery solutions to be treated are reduced by a factor of 1.2. EFFECT: increased desalting degree; reduced power consumption; simplified process. 1 dwg, 1 tbl