METHOD OF INTEGRATED PROCESSING OF NATURAL MINERALIZED WATERS Russian patent published in 2002 - IPC

FIELD: chemical engineering. SUBSTANCE: invention relates to production of high-utility mineral substance from natural waters such as associated oil-deposit waters and oceanic waters. Method involves following consecutive stages: mechanical filtration, adsorption isolation of calcium, isolation of magnesium via passage of filtrate through carboxylic cationite in Na+ form, concentrated sodium chloride solution-mediated regeneration of adsorbent followed by treating regenerate to yield carbonates, electrodialysis-mediated concentration of treated water to give secondary solutions and desalted water, and additional strontium carbonate and iodine recovery stages. Stages of selective isolation of calcium, magnesium, and strontium are performed in countercurrent ion- exchange tower with separation of softened water and strontium and magnesium compound-containing brine flows followed by precipitation of magnesium in the hydroxide form by treatment with sodium hydroxide solution, filtration through mechanical filter and treatment of filtrate with sodium carbonate solution to isolate strontium carbonate. Iodine recovery is performed by treating water with hydrochloric acid solution to attain pH 2,0-2,5, adding chlorine water as oxidant in amount corresponding to 1.1 equivalents chlorine per 1 equivalent iodine, and passing solution through anionite AB-17 in Cl- form, which is regenerated with solution containing 65-75 g/l sodium sulfite and 130-150 g/l sodium chloride followed by recovering elementary iodine from regenerate solution. Reagents needed for implementation of process, in particular chlorine water and sodium hydroxide and hydrochloric acid solutions are obtained from the secondary electrodialysis solution via electrolysis in diaphragm electrolyzer. Method provides integrated and economically advantageous technology for recovering high-utility mineral raw materials from natural waters. Additionally recovered from water are strontium and iodine and reagent needed for use in the process. Closed-cycle technology yielding recovered solutes and water is elaborated. EFFECT: enabled efficient recovery of increased number of high-utility water-dissolved chemicals. 2 dwg, 4 tbl