COMPOSITION AND METHOD FOR INCREASING OIL RECOVERY OF OIL RESERVOIRS Russian patent published in 2016 - IPC C09K8/68 C09K8/88 E21B43/22 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to development of oil strata with inhomogeneous, low-permeable, mudded off collectors with artificial cracks and wall packing of pore space by clay material, asphalt-resin-paraffin deposits. Composition for increasing oil recovery of oil formations containing aqueous solutions of surface active substance - SAS and polyacrylamide (PAA), contains surfactant solution 0.5-15 % aqueous solution of anionic micelle-forming natural soap - AMNM, solution of PAA 0.3-5 % aqueous solution of PAA with molecular weight of up to 18 million units and additionally 0.1-1 %-water suspension of ultrafine carbon nanometric - UDNMU in following proportions, wt %: said solution AMNM 10-90, said solution PAA 9.9-89, said suspension 0.1-1. Method of increasing oil recovery of oil formations, which involves desorption of residual oil capillary and aqueous solutions of surfactants and displacement of residual oil to producing wells of viscosity agents based on aqueous solutions of PAA converted in "Microgel" under the effect of "stitches", for example, aqueous solutions of salts of metals is used the above composition, before pumping of which is injected into oil reservoir mixture 0.5-15 % aqueous solution of AMNM and 0.1-1 % aqueous suspension UDNMU It is pushed in the contact zone, the front of oil displacement with water and low-permeable mudded off part of the oil formation, its metal salt is extracted from clay material of said part for cross-linking PAA and formation of Microgel. Invention is developed in subclaim.

EFFECT: increased oil recovery, including in formations with high content of residual oil and high-viscosity oil deposits.

3 cl, 10 tbl