METHOD OF TREATING RECYCLED WATER FROM METALLURGICAL PRODUCTION Russian patent published in 2011 - IPC C02F9/08 C02F1/28 C02F1/42 C02F1/44 C02F1/52 C02F1/62 C02F1/66 C02F101/20 

FIELD: chemistry.

SUBSTANCE: invention relates to methods of treating recycled water from metallurgical production with high content of heavy metal phosphates and salts thereof, and can be used in metallurgical production. The method involves further reactant precipitation with lime milk and flocculant at pH=10.5-11.5, followed by packing the precipitate after selling in a sludge densifier and drying the precipitate on a press filter. Suspended substances are removed from the water on a filter with granular filler. The water is then demineralised on an ion-exchange filter filled with weakly acidic cation-exchange resin in Na form. The water is then purified on a fine filter and then desalinated on a two-step reverse osmosis apparatus at pH=7-7.5. Process water pressure at the first step of the reverse osmosis apparatus is equal to 20 kgf/cm² and 55 kgf/cm² at the second step. The purified water used is filtrate from the first step. The filtrate from the second step is returned for re-purification at the first step.

EFFECT: method increases quality of the purified water and efficiency of the process owing to low consumption of chemical agents.

4 cl, 2 dwg, 1 tbl