METHOD FOR REPEATED HYDRAULIC FRACTURING IN HORIZONTAL WELLS Russian patent published in 2020 - IPC E21B43/267 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry and can be used to increase efficiency of development of oil deposits. Method of re-controlled hydraulic fracturing treatment (HFT) in horizontal well with previously performed multistage hydraulic fracturing involves detecting based on current physical-dynamic and geomechanical characteristics of formation and formation fluid of at least one crack with low efficiency of operation, due to low permeability. Shutdown of well operation and pumping of fluid with bottomhole pressure not exceeding formation fracturing pressure. At that, numerical calculation of stress-strain state in all fractures of the well is performed by the method of finite elements and pressure is determined for cracks closure depending on change of formation pressure in the area of ports of the well assembly. Pumping is performed until moment of time, when pressure of closing cracks with high permeability will be higher, than in detected crack with low permeability. Then fluid pumping into the well is stopped and hydraulic fracturing is performed, which leads to flow of hydraulic fracturing gel to the area of low closing pressure and subsequent cracking of the crack with low permeability and low efficiency of operation, after which the horizontal well is put into operation.

EFFECT: technical result consists in improvement of efficiency of oil extraction from horizontal well with multiple HFT cracks due to repeated controlled HFT, which provides conversion of stress-strain state of bed for crack splitting with low efficiency of operation.

1 cl, 6 dwg