METHOD OF HYDRAULIC FRACTURING AT LATE STAGE OF MINE WORKING Russian patent published in 2020 - IPC E21B43/26 

FIELD: oil, gas and coke-chemical industries.

SUBSTANCE: invention relates to oil industry, in particular to methods of increasing oil recovery of formation by formation of cracks or breaks. Method includes extraction of formation products through production wells with control of volumes of extraction of formation products, pumping of working agent through injection wells with excess of pumping volumes above sampling, isolation of absorption zones and the most permeable sections of the formation by means of the colmatage composition at increased watering of the extracted product in the injection wells and performance of the fracturing in the well. Geophysical investigation of average length of fracture during formation fracturing. Time-constant material is injected into the injection well by the colmatage composition to form a screen with radius of not more than 1/4 and not less than 1/8 of the fracture average length during fracturing. Fracturing is performed in injection well after curing of cement mortar.

EFFECT: proposed from the method of hydraulic fracturing of the formation at the late stage of development allows reducing the costs for injection into operation of injection wells after isolation of absorption zones and most permeable sections with the colmatage composition, exclude probability of recovery of permeability of formation zones and absorption zones and involvement in development of previously undrained sections of formation by setting impermeable screen from hardened cement mortar (cement stone) around injection well after pumping colmatage composition and performing fracturing after cementing cement.

1 cl