METHOD FOR OIL PRODUCTION FROM UNDERGROUND OIL DEPOSITS Russian patent published in 2016 - IPC E21B33/138 E21B43/22 C09K8/58 E21B43/16 

FIELD: oil industry.

SUBSTANCE: invention relates to oil production, particularly to a method of oil extraction from underground oil deposits. Method assumes penetration of at least one injection well and at least one production well. One or more displacement media are forced in at least one injection well, and oil is extracted through at least one production well. Zones of oil deposit with high permeability in the area between at least one injection well and at least one production well are locked out, for this purpose at least one F₁ aqueous composition of and at least one F₂ aqueous composition is forced through at least one injection well in deposit in each case individually and in series. Compositions after pumping get mixed with each other in the formation in the zone of mixing and form viscous gels. Continued injection of one or several displacement in injection well. Composition F₁ includes water and urotropine. Composition F₂ includes water and urea. F₁ and/or F₂ contain at least one compound M selected from compounds of metals and compounds of semimetals, compound M is gel-forming on addition of alkali. Compounds of metals and compounds of semimetals are selected from the group of salts Fe (II) and Fe (III), vanadium salts, zirconium salts, aluminium salts (III), and silicon colloidal compounds. In zone of mixing, urotropine concentration is at least 1 wt%, urea concentration is at least 5.75 wt%, and concentration of at least one compound M is at least 5 wt% relative to the sum of water, urotropine, urea and at least one compound M located in the zone of mixing.

EFFECT: technical result is higher oil yield.

13 cl, 2 tbl, 3 dwg