METHOD FOR INCREASING OIL RECOVERY OF A CARBONATE RESERVOIR OF THE BASHKIRIAN STAGE Russian patent published in 2024 - IPC E21B43/26 E21B43/22 E21B37/06 E21B47/06 C09K8/524 C09K8/58 C09K8/64 

FIELD: oil industry.

SUBSTANCE: in the method of increasing oil recovery carbonate reservoir of the Bashkirian stage a number of production wells are drilled at distance of 350 m from each other. Further, two rows of injection wells are drilled symmetrically relative to production wells at distance of 250–300 m. Formation pressure Pf and formation thickness are determined. One row of injection wells is stopped, in another row of injection wells carry out simultaneous composition injectioncontaining, wt. %: rapeseed oil 76–81; palm oil 7–10 and xylene 12–14, volume per one injection well is 10 m³ per 1 m of formation thickness under pressure of 1.5*Pf. Then injection wells are stopped for reaction within 48 hours. Further, a row of injection wells is simultaneously started and water is pumped for 30 days with daily volume of 40–50 m³/day and pressure equal to 1.1*Pf. Then a row of injection wells is stopped. Then another row of injection wells is selected and operations are repeated, starting with simultaneous injection of the composition.

EFFECT: increasing efficiency of oil deposit development by reducing viscosity of extracted oil, increasing formation coverage by action, uniformity of oil reserves development, increasing oil displacement factor.

1 cl, 2 tbl, 5 ex