METHOD FOR TREATING BOTTOM-HOLE ZONE OF WELL Russian patent published in 1998 - IPC

FIELD: oil production industry. SUBSTANCE: this particularly relates to treating bottom-hole zone in horizontal or inclined bores of producing wells with final purpose of increasing efficiency of acid treatment. According to method, carried out is interval-by-interval injection of acid solution into bottom-hole zone. Selected in horizontal or inclined bores of wells is interval with lowest injectivity. Determined is initial injection pressure at which interval accepts acid solution. Also determined is final injection pressure. Final injection pressure is lower than initial injection pressure by at least 20%. Injection of acid solution into remaining intervals is continued until reaching final injection pressure which is similar for all well intervals being treated. At initial pressure of injection into separate interval equal to final value, injection of acid solution into given interval is discontinued. At initial injection pressure which is lower than final value, operations are undertaken to reduce permeability of given interval. EFFECT: higher efficiency.