METHOD ADJUSTING FRONT OF FLOODING OF OIL POOLS Russian patent published in 2000 - IPC

FIELD: oil production, development of oil fields at late stage. SUBSTANCE: according to proposed method of adjustment of front of flooding of oil pools oil is sampled through production wells, working fluid is periodically pumped down through injection wells, at least one injection well is stopped and technological stand-up is kept till current seam pressure is restored in face zone of well. Aqueous solutions of polymer and silicate of alkali metal are mixed with water having mineralization of 15.0-180.0 g/l prior to pumping-down. Mixture is pumped down in portions. Transition from one portion to another is carried out with rise of pumping pressure by 0.5 MPa and more and quantity of water-soluble polymer and silicate of alkali metal is reduced in each next portion. In this case total reduction of quantity of water-soluble polymer lies within limits from 0.1 to 0.001 mas.% and of quantity of silicate of alkali metal - within limits from 10.0 to 0.1 mas.%, mineralized water being the balance. Polyacrylamide or cellulose esters are used as water-soluble polymer. Technical result of invention lies in enhanced oil recovery from field thanks to enlarged coverage and forcing of oil from adjacent interlayers not used in production before. EFFECT: enhanced oil recovery. 1 cl