METHOD FOR WATER ISOLATION IN THE BOTTOM-HOLE ZONE OF THE PRODUCTION WELL Russian patent published in 2022 - IPC E21B33/138 

FIELD: oil industry.

SUBSTANCE: invention relates to the oil industry, in particular to a method for conducting water isolation work in a well during the development of an oil deposit underlain by water. The method for isolating water in the bottom-hole zone of a production well with hydraulic fracturing involves pouring an insulating composition into the well with a preliminary determination of the volume of the insulating composition and pressing it into the formation. At the same time, a well is selected that is water-encroached exclusively due to the formation of a cone of water. The required volume of the insulating composition V_gen. is determined by the formula V _gen. = V₁ + V_gen.fr., where V₁ is the volume of the well from the lower edge of the perforation to the bottom of the well, V_gen.fr. is the volume of the aquifer of the fractured space. Volume V_gen.fr. it is calculated by the formula V_gen.fr. = V_pr.∙h₃/h₁, where V_pr. is the volume of proppant injected during hydraulic fracturing, m³, h₁ is the capacity of the oil reservoir, m, h₃ is the capacity of the aquifer part of the reservoir, m. The insulating composition of the volume of V_gen. is poured. into the selected well, a pressing fluid is pumped into the well to press an insulating composition through the perforation holes of the well, creating excessive hydrostatic pressure of the sales fluid column, for gravitational replacement of reservoir water in the fracture and the formation of a waterproof anti-filtration insulating shield at the base of the fracture in the bottom-hole zone of the formation. A weighted polymer solution is used as an insulating compound, and water is used as a pressing fluid. Moreover, an insulating composition and a pressing liquid of such density are chosen, at which the hydrostatic pressure of the column of the insulating composition and the hydrostatic pressure of the column of the pressing liquid exceeds the residual reservoir pressure.

EFFECT: increase in the efficiency of water isolation in the bottom-hole zone of oil-production wells with a simultaneous reduction in the complexity and duration of water isolation work.

1 cl, 4 dwg