HYDRAULIC FRACTURING METHOD Russian patent published in 2023 - IPC E21B43/26 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to a method of hydraulic fracturing in combination with isolation of water inflows in production wells using gel-forming liquids based on hydrocarbon and water, and can also be used to limit water inflows into oil and gas wells. The method of hydraulic fracturing includes lowering a pipe string with a packer into the wellbore of a productive well, closing the annular space above the roof of the productive formation, pumping an insulating composition, subsequent injection of a linear gel, pumping a cross-linked gel into the formation, performing mini hydraulic fracturing using a proppant carrier fluid, squeezing the fluid proppant carrier and further implementation of the main hydraulic fracturing. At the same time, the cross-linked gel is pumped into the formation at a pressure higher than the hydraulic fracturing pressure of the formation and with the control of the flow rate of fluid components. Before hydraulic fracturing, the results of hydraulic fracturing are analyzed for adjacent wells in terms of determining the crack opening pressure, exposure interval, the relationship between the lithological type of the rock and the concentration of the modifier for this type of rock. Next, the lithological type of the rock is determined in the zone of hydraulic fracturing and the selected exposure interval is perforated. After that, a water-based phase permeability modifier is injected at a pressure below the fracture opening pressure. Next, he water-based phase permeability modifier is replaced with a linear gel. After that, a linear gel and a phase permeability modifier are injected with a concentration of at least 10 l/m³ with an increase in discharge pressure to a pressure at which the fracture opens. Next, a mini hydraulic fracturing is carried out with simultaneous injection of a cross-linked gel and a phase permeability modifier with a concentration of at least 10 l/m³, and the stage of the main hydraulic fracturing is carried out on a cross-linked gel with proppant, with the addition of a clay stabilizer and a liquid enzyme destructor.

EFFECT: creation of a method of hydraulic fracturing, which allows hydraulic fracturing of the formation both in flooded wells and in formations where water breakthrough and increase in water cut are possible after the hydraulic fracturing process.

2 cl, 1 tbl