PROCESS OF THERMAL AND CHEMICAL TREATMENT OF FACE ZONE OF POOL Russian patent published in 2001 - IPC

FIELD: oil production. SUBSTANCE: invention is specifically related to methods of thermal and chemical treatment of production and injection wells. Process of thermal and chemical treatment of face zone of pool includes consistent pumping of saturated aqueous solutions of carbamide, sodium nitrate and hydrochloric acid in the form of two concentrated 65-70 vol.% kinematically and aggregately stable emulsions of water-in-oil type pumped into face zone of pool. Dispersive phase of one emulsion is presented by mixture of saturated aqueous solutions of carbamide and sodium nitrite with density 1250 kg/cu.m. The other emulsion includes concentrated 31% hydrochloric acid with density 1190 kg/cu. m. Mixture of kerosene- gas oil fraction of oil hydrocarbons and heavy solvent (TO 2122-199-005-76-3468-94) is used in the capacity of dispersive medium to prepare water-in-oil emulsions displaying high kinematic and aggregate stability. Oil extraction reagent (TO 2458-001-21660-06-97) in the amount of 0.5-10.0 mas.% on basis of dispersive medium in which given reagent is dissolved in advance is used as stabilizer of water-in-oil emulsion. While given emulsions are mixed on well face there occurs their spontaneous destruction with release of considerable amount of heat, gaseous components and mixture of hydrocarbon oil solvents and heavy solvent. EFFECT: enhanced degree of heating of face zone, removal of asphalt-resin and paraffin deposits, improved filtration characteristics of face zone. 2 cl, 1 tbl