COMPOSITION FOR REPEATED EXPOSURE OF PRODUCING OIL FORMATION Russian patent published in 1995 - IPC

FIELD: oil-producing industry. SUBSTANCE: method curtails the time from the beginning of simulating the oil inflow to the production of pure oil from the well, reducing the expenditure of materials and time for liquidation of stable hard-to-break oil-water emulsion formed in well and formation which precedes the flow of pure oil by preventing the formation of such emulsion directly in the shaft with simultaneous retaining of initial permeability of producing formation. Method involves filling the well shaft with liquid composition for repeated exposure of producing formation and perforation of said formation, simulating the inflow of formation fluid to the surface to obtain pure oil, and liquidation of the waste products of repeated exposure. Said composition is polyacrylamide, nonionogenic surfactant and mineralized solution based on salts of potassium and/or sodium taken in the following ratio, wt.-%: polyacrylamide, 0.002-0.020; nonionogenic surfactant, 0.001-0.01, and mineralized solution based on salts of potassium and/or sodium, the balance. EFFECT: higher efficiency. 2 tbl