METHOD OF DEVELOPING LOW-PERMEABILITY RESERVOIRS Russian patent published in 2024 - IPC E21B43/20 G01N15/08 

FIELD: oil industry.

SUBSTANCE: invention relates to oil industry and can be used for development of low-permeability reservoirs. Disclosed is a method of developing low-permeability reservoirs, in which during operation water injection is monitored and oil recovery and water content are monitored. At that, laboratory tests of core are carried out, where permeability is determined at successive pumping of formation, high-mineralized and low-mineralized water. Based on them, permeability recovery coefficients are calculated after pumping high-mineralized and low-mineralized water. Also, in laboratory studies of core oil displacement coefficients are determined after successive oil displacement first with highly mineralized water, and then with low-mineralized water, and critical oil saturation at oil displacement with highly mineralized water. Further, a geological-hydrodynamic model of the reservoir section is constructed, where at first modelling is carried out when pumping high-mineralized water using the corresponding value of critical oil saturation. Then simulation is carried out when pumping low-mineralized water to simulate switching. At the same time for each value of water cut from 0 % to 100 % with the selected spacing the corresponding value of oil saturation and coefficient of permeability recovery at pumping of low-mineralized water is used. Based on the simulation results, graphs of the relative oil recovery factor (ORF) dependence on water cut are plotted and the water cut value corresponding to the ORF maximum is determined, and when this water cut is achieved, high-mineralized water is directly switched to low-mineralized water.

EFFECT: increasing oil recovery of low-permeable reservoirs.

1 cl, 3 dwg