METHOD FOR DEVELOPING A HETEROGENEOUS OIL RESERVOIR Russian patent published in 2023 - IPC E21B43/22 

FIELD: oil industry.

SUBSTANCE: invention relates to a method for developing a heterogeneous oil reservoir. A method for developing a heterogeneous oil reservoir includes injecting two rims into the reservoir through an injection well. The first fringe is a mixture of an aqueous solution of polyacrylamide with a crosslinker. The second fringe is an aqueous solution of a surfactant. The initial injectivity of the injection well at the injection pressure and the salinity of the injected water are preliminarily determined. Then two rims are sequentially pumped. The first slug is injected until the injection pressure increases by 5-15% of the initial injection pressure. In the first slug, a mixture of an aqueous solution of polyacrylamide with a crosslinker is pumped. The second slug is injected until the injection pressure increases by 20-60% of the initial injection pressure, which does not exceed the maximum allowable pressure on the production casing. In the second slug, a mixture of an aqueous solution of a complex surfactant, a water-soluble polymer, and water is pumped. The volume ratio of the rims is chosen depending on the initial injectivity of the injection well.

EFFECT: ensuring the non-stop operation of the well, in reducing the loss of surfactants in the washed high-permeability zones of the reservoir, in increasing the coverage of the reservoir by the impact and leveling the oil displacement front, in connecting the oil-saturated reservoir zones that were not previously covered by the impact.

1 cl, 2 tbl