METHOD FOR DEVELOPMENT OF OIL RESERVOIR HETEROGENEOUS IN PERMEABILITY Russian patent published in 2021 - IPC E21B43/22 E21B43/16 C09K8/584 

FIELD: oil field development.

SUBSTANCE: invention relates to the development of an oil field and can be used in the development of an oil reservoir with reservoirs heterogeneous in permeability to regulate the injectivity profile of an injection well, increase the oil displacement ratio by involving in the development of low-permeability oil-saturated reservoirs that were not previously affected by the impact. The method includes preliminary determination of the permissible injection pressure and injectivity of the injection well, injection of invert emulsion. In this case, the invert emulsion is pressed through with mineralized water in a volume of 0.5 of the volume of the invert emulsion. When the injectivity of the injection well is below 250 m³/day, after the injection of the invert emulsion, a slug of a hydrocarbon solution of a nonionic surfactant is injected with a concentration of 4-6 wt% in the ratio of the volumes of the hydrocarbon solution of nonionic surfactant and invert emulsion 1:(2-2.9). When the well injectivity is above 250 m³/day, after the injection of the invert emulsion, a rim of the nonionic surfactant hydrocarbon solution is injected with a concentration of 4-6 wt% in the ratio of the volumes of the nonionic surfactant hydrocarbon solution and invert emulsion 1:(3-4). In this case, waste or formation water with a salinity of 1 to 300 g/l is used as saline water, and hydrocarbon solutions of alkylphenol with a carbon chain length of C-9 and a degree of oxyethylation - 12 neonol AF 9-12 or alkylphenol are used as a hydrocarbon solution of nonionic surfactants with a carbon chain length C-9 and a degree of oxyethylation - 6 neonol AF 9-6.

EFFECT: improving the efficiency of the method of developing a reservoir of heterogeneous permeability.

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