METHOD FOR DEVELOPMENT OF MULTI-FACE LOW-PERMEABLE OIL DEPOSIT BY ELECTRIC FRACTURE Russian patent published in 2020 - IPC E21B43/16 E21B43/14 E21B43/26 E21B43/17 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry and can be used in development of multilayer low-permeability oil formations using formation electric fracturing. According to the method, vertical and/or directional wells already existing on the deposit are drilled and/or selected. Invention envisages use of electroconductive casing string and/or electroconductive cement ring, lowering of electrodes into wells, formation electric fracturing due to creation of electric arc between electrodes, extraction of products from wells. At the same time the deposit consisting of at least two productive strata coinciding in the structural plan is selected. Each of the beds can be layered. Distance between the bottom of the uppermost formation and the roof of the lowest formation is not more than 500 m. Distance between adjacent boreholes is not more than 400 m. Electrodes are arranged so that electrodes of different polarity are located in adjacent wells, between shafts of which distance is least. Electrodes with one polarity are placed opposite the uppermost formation in wells of group A. Electrodes with opposite polarity are placed opposite the lowest formation in wells of group B. After the electric fracturing of the formation, wells of group B are released into production. At reduction of oil flow rate in wells of group B up to 1 t/day and below them are stopped. Group A wells are released into production. When oil flow rate in wells of group A is reduced to 1 ton/day and lower, they are stopped. In all wells of groups A and B working agent is pumped. Then these wells are left for redistribution of pressure for 5–15 days. After that, all wells of groups A and B are put into production. Working agent injection and waiting periods are repeated.

EFFECT: increasing oil recovery of a deposit.

1 cl, 2 ex