TITANOUS COAGULANT USED FOR PURIFICATION OF OIL-CONTAINING OILFIELD SALTWATER UP TO POTABLE WATER QUALITY, METHOD THEREOF (VERSIONS) AND COMPLEX SYSTEM THEREOF Russian patent published in 2009 - IPC C02F1/52 C02F9/08 C02F1/24 C02F103/04 

FIELD: chemistry.

SUBSTANCE: method lies in usage of titanous coagulant containing oxides, hydroxides, sulphates, titanium oxyhydrosulphates, chlorides and titanium, aluminium and silicon oxyhydrochlorides for purification of oil-containing oilfield saltwater up to potable water quality. The purification technology includes coagulation and clarification; at first the two-stage floatation is carried out including water purification from oil products in the first stage and adding of the water solution of flocculent - calcined soda and/or lime in the amount not less than 100 g of calcined soda and not less than 100 g of lime on a dry basis per 1 m³ of the purified water on the second stage; after completing the second stage the purified water settling is carried out up to precipitation of the mechanical admixtures and hardness salts, then coagulation is implemented by adding to the clarified oilfield water of the titanous coagulant solution as in point 1 in the amount not less than 20 g on a dry basis per 1 m³ of the purified water up to decrease of oil products content in the purified water up to less than 0.05 g/m³. Then the final water purification is carried out by method of reverse osmosis up to achieving of potable water quality. The complex system for purification includes the devices needed for methods implementation with contact clarifier being connected through high-pressure pump with membrane units of reverse osmosis, settler being connected with inclined floatator having not less than 10 floatation chamber. The pipe-line connecting the contact clarifier with settler is provided with not less than 4 coupling positioned on the distance not less than 1 m of the contact clarifier inlet and intended for flocculent feed.

EFFECT: decontamination and decrease of oil products content in the purified water up to value best than 0,05 mg/l corresponding to the standards of environmental safety without excessive capital and operating costs.

8 cl, 2 dwg, 14 tbl, 11 ex