METHOD FOR INTERVAL-AFTER-INTERVAL TREATMENT OF BOTTOM-HOLE ZONE OF HORIZONTAL WELLS Russian patent published in 2000 - IPC

FIELD: oil production industry. SUBSTANCE: method can be used for increasing output from bottom-hole zone of horizontal wells. Effective treatment is achieved due to selective treatment of productive intervals and isolation of treated intervals. According to method, oil emulsion is injected over entire profile of horizontal bore being treated together with injection of acid solution which is undertaken during period ensuring solving of productive bed in treated zone which is determined from following expression: V = A•C_HCl•T^-K, where V - speed of solving of productive bed rock, C_HCl - concentration of acid solution, T - time period of injecting acid solution, K - coefficient of acid solution activity, A - coefficient of bed non-uniformity. Intervals treated by oil-acid solutions are blocked off after each acid treatment by successively increasing viscosity of oil-acid emulsion and reducing its stability as interval being treated is moving from bottom-hole zone of well towards point of introducing into productive bed. Application of method ensures increasing of permeability of low-productive intervals together with increasing current output of horizontal wells. EFFECT: higher efficiency. 1 dwg