WELL BOTTOMHOLE ZONE TREATMENT METHOD Russian patent published in 2018 - IPC E21B34/06 E21B43/27 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the petroleum industry. Method comprises equipped with a packer, fluid pulsed injection device, destructible valve, perforated pipe with a bushing inside pipe string lowering into the reservoir perforation interval. Also, this method comprises the solvent injection through the pipes string in the continuous mode with a flat packer, well with solvent technological exposure, four cycles of the process fluid injection into the reservoir through the pipes string and the well annular space, the solvent and the reaction products washing out by backwashing. For the fluid pulsed injection by the pipe string raising, installing the fluid impulsive injection device opposite the formation bottom and a packer is fitted. Then moving the bushing down relative to the perforated branch pipe and sealing the perforated pipe holes. Cutting off the destructible valve with the process fluid overpressure, by the pipes string performing the hydrochloric acid 10–15 % aqueous solution pumping into the reservoir in a pulsed mode and flushing with this fluid in a pulsed mode. Next, performing the technological exposure for the response and performing the reaction products extraction by swabbing. Novelty is that the perforated branch pipe holes sealing is carried out from the hydrochloric acid 10–15 % aqueous solution pressure acting on the dropped into the pipe string ball. Ball is made with possibility of the bushing hole closing. At that, the bushing is installed with fixation from axial movement by the shear screw on a cylindrical protrusion made on the perforated branch pipe inner wall and closing this pipe holes. From the cylindrical protrusion upper end face opposite each of the perforated branch pipe hole blind holes are drilled, communicating with this branch pipe holes. From the bushing upper end face the cylindrical recess with a conical bottom is made to fit the ball. From the bushing upper and lower end faces radial grooves are made. At that, the radial grooves at the bushing upper end face protrude beyond the perforated pipe cylindrical protrusion upper end face. At the formed by the radial grooves on the bushing upper end face protrusions end face, a ring is installed, configured to close the perforated branch pipe cylindrical protrusion blind holes after the bushing is moved down. Ring inner diameter is selected larger than the ball diameter.

EFFECT: technical result consists in reduction in the well reservoir treatment time.

1 cl, 2 dwg