METHOD FOR DEVELOPMENT OF SUPERVISCOUS OIL FORMATION WITH ACID TREATMENT Russian patent published in 2025 - IPC E21B43/24 E21B43/27 

FIELD: obtaining oil from wells.

SUBSTANCE: invention relates to oil industry and can be used in development of high-viscosity and bitumen oil deposits. Disclosed is a method of developing a superviscous oil formation with conducting acid treatments, which includes using a pair of horizontal injection and production wells, the horizontal sections of which are arranged in parallel one above the other in the vertical plane of the treated formation, running-in of tubing strings or long-length flush-joint pipes – LFP of coiled tubing combined unit, allowing simultaneous pumping of heat carrier and extraction of products, pumping of coolant, heating of treated formation with creation of steam chamber, extraction of products through production well via tubing string or LFP and control of process parameters of formation. At that, tubing strings or LFP are lowered into production and injection wells with their ends shifted horizontally relative to each other from 25 m to 300 m. Treatment of the bottomhole zone of production and injection wells is carried out through the corresponding tubing string or LFP with an acid composition, which is 6-10 % inhibited hydrochloric acid with an open casing valve on the wellhead equipment of the production or injection well with control of the acid composition injection rate to prevent possible outflow of liquid from the open casing valve. Then the tubing string or LFP is lifted by 50-100 m of the corresponding well and the acid composition is pumped with closed casing valve at least 3 times. After injection of acid solution, acid composition is flushed with water through appropriate tubing string or LFP, not exceeding permissible pressure of formation seal.

EFFECT: increased productivity of production well and injectivity of injection well due to acid treatment from deposits of carbonate and sulphate salts.

4 cl, 2 dwg