DEVELOPMENT METHOD OF BOTTOM-HOLE ZONE Russian patent published in 2014 - IPC E21B43/27 E21B43/22 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry. Method of bottom-hole zone treatment includes running-in of pipe string with packer to perforated interval, washing of the well, packer seating in production casing with master and casing valves above the formation and pumping of hydrochloric acid solution through the pipe string in pulsed mode, process exposure for reaction and extraction of reaction products. Optimal intake of the formation is set before treatment of bottom-hole zone. At the well mouth the pipe string below packer is equipped with impulse liquid pulsator, at that a valve is mounted between the packer and liquid pulsator; pipe string is run-in into the well so that packer is located above the formation; thereafter the well is flushed with process liquid at open master and casing valves by straight ring circulation in pulse mode during 10-20 minutes. The casing valve is closed and process liquid is pumped into the formation under pressure that does not exceed permitted pressure to the production string during 5-10 minutes. The casing valve is closed and process liquid is drained from the well. Washing and drainage of process liquid is repeated 3-5 times. Then actual intake of the formation is determined at pressure that does exceed permitted pressure to the production string. If actual intake is lower than the optimal one then hydrochloride acid bath is installed in the well opposite formation interval under pressure that does not exceed permitted pressure to the production string. If actual intake is equal to the optimal one or higher then hydrocarbon solvent is pumped to the pipe string, add process liquid up to volume bigger per 0.5-1 m³ than volume of the reagent displaced from the pipe string under pressure not exceeding permitted pressure to the formation. The well is subjected to process exposure. When exposure is completed the valve is actuated, liquid pulsator is cut off, the packer is released, the pipe string is run-in additionally so that radial openings of the valve are located opposite the formation; by return ring circulation reaction products are washed out during 3-5 hours, at that fluid influx from the formation is controlled. Then casing valve is closed and by process liquid pumping to the pipe string through the valve well intake is determined under intake pressure of the formation.

EFFECT: increasing efficiency of bottom-hole zone treatment due to increase of bottom-hole zone intake with simultaneous simplification of process and reduction of treatment duration.

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