METHOD OF EXTRACTION OF OIL FROM HETEROGENEOUS ON THE PENETRATION OF OIL STRUCTURES (OPTIONS) Russian patent published in 2019 - IPC E21B43/22 

FIELD: oil, gas and coke-chemical industries.

SUBSTANCE: invention relates to the oil industry, in particular to methods for extracting oil from oil reservoirs with heterogeneous permeability. In one embodiment, in the method of extracting oil from oil reservoirs that are not uniform in permeability, including the preparation and injection of a micellar solution - MP containing hydrocarbon fluid - SL, surfactant, isopropyl alcohol and fresh water, pre-determine the initial injection capacity of the injection well - APSN at the initial injection pressure and water salinity - MV, with NPNS 100–250 m³/d and MV 0.15 g/dm³ MP pumped in a volume of 2–10 m³ on 1 m thickness of the productive formation - m³/m CCI, as a surfactant used ethoxylated alkylphenol with a degree of ethoxylation of 4 or 6, or a water-alcohol solution of a mixture of monoalkyl ethers of polyethylene glycol 90 wt. % and alkyldimethylbenzylammonium chloride 10 wt. %, or an aqueous solution of a mixture of oligomers C₈-C₁₀ alkyl glucosides with a mass fraction of the basic substance of at least 70 %, or alkylpolyglucoside C₈-C₁₀ in the following ratio, wt. %: UZH is 25.0–40.0, the specified surfactant is 10.0–20.0, isopropyl alcohol is 1.0–10.0, fresh water is the rest being, then pumped the rim of an aqueous solution of polyacrylamide - PAA, containing, % by weight: PAA is 0.1–1.5, water with mineralization 0.15 g/dm³ is the rest, when the ratio of the above solution and the rim 1:(1–10) by volume and forced into the reservoir with mineralized water 0.15 g/dm³ in the amount of 15 m³. In another embodiment, in the specified method with NPNS 250–600 m³/d and MV 0.15 g/dm³ pump the rim of the aqueous dispersion of wood flour - VDDM with a concentration of 0.5–3.0 wt. % or aqueous solution of PAA with clay powder - GP containing, % by weight: PAA is 0.01–1.0, GP is 1–10, water with mineralization 0.15 g/dm³ is the rest being, or an aqueous solution of PAA with chromium alum - HKK, containing, % by weight: PAA is 0.1–1.0, HCC is 0.005–0.3, water with a salinity of 0.15 g/dm³ - the rest being, to increase the injection pressure by 5–20 % of the initial injection pressure - IIP, then the above-mentioned MP is pumped in a volume of 2–10 m³/m TPP, then pumped the rim of an aqueous solution of PAA, containing, % by weight: PAA is 0.1 to 1.5, water with a salinity of 0.15 g/dm³ is the rest being, when the ratio of the above solution and the rim is 1:(1–10) by volume and is forced into the formation with water with a salinity of 0.15 g/dm³ in the amount of 15 m³. According to the third option in the specified method with NPNS 100–250 m³/d and MV 0.5–300 g/dm³ pumped a fresh water rim in a volume of 15 m³, then MP in the volume of 2–10 m³/m CCI, then the rim of an aqueous solution of PAA, containing, % by weight: PAA is 0.1–1.5, water with mineralization 0.5–300 g/dm³ is the rest being, when the ratio of the above solution and the rim is 1:(1–10) by volume and is forced through with mineralization water of 0.5–300 g/dm³ in the amount of 15 m³. In the fourth option in the specified method with NPNS 250–600 m³/d and MV 0.5–300 g/dm³ pump the rim of VDDM with a concentration of 0.5–3.0 wt. % or an aqueous solution of PAA with GP containing, % by weight: PAA is 0.01–1.0, GP is 1–10, water with a salinity of 0.5–300 g/dm³ is the rest being, or an aqueous solution of PAA with CCK containing, % by weight: PAA is 0.1–1.0, HCC is 0.005–0.3, water with mineralization 0.5–300 g/dm³ is the rest being, to increase the injection pressure by 5–20 % of the IIP, then pump the fresh water rim in a volume of 15 m³, then specified MP in the amount of 2–10 m³/m CCI, then pumped the rim of an aqueous solution of PAA, containing, % by weight: PAA - 0.1–1.5, water with mineralization 0.5–300 g/dm³ is the rest being, when the ratio of the specified solution and the rim 1:(1–10) by volume and forced into the reservoir with water with a salinity of 0.5–300 g/dm³ in the amount of 15 m³.

EFFECT: technical result is an increase in oil recovery, improving the efficiency of the formation coverage by the impact and expanding the technological capabilities of the method.

4 cl, 4 ex, 8 tbl