PROCEDURE FOR TREATMENT OF PAYABLE CARBONATE BED Russian patent published in 2015 - IPC E21B43/27 E21B43/16 

FIELD: oil and gas industry.

SUBSTANCE: according to the method upon identification of treatment intervals in oil-bearing rocks of carbonate bed at the wellhead the pipe string is equipped with a funnel with a plug catching baffle for a gate, a jet nozzle, the centralizing tube and a filter. A sleeve covering inner openings is fixed with a shear bolt inside the filter. At open casing valve at the wellhead the pipe string is run into the well with flushing by process fluid and rotating. The jet nozzle is set opposite the treatment interval of open horizontal borehole. The gate is thrown to plug catching baffle of the spherical funnel. Axial movement of the pipe string is started from the wellhead to the bottomhole. At that within treatment intervals acid is injected by portions through the pipe string in water jet mode. When the spherical funnel reaches bottomhole of an open horizontal bottomhole the casing valve is closed at the wellhead. Axial movement of the pipe string is made from the bottomhole to the wellhead. Sandy and aqueous solution of surfactant is injected to the pipe string in hydraulic jet mode. The pipe string is rotated per 180° and the above process is repeated starting from opening of the casing valve and axial moving of the pipe string from the wellhead to the bottomhole and completing with reaching by the jet nozzle of the treatment interval closest to the wellhead. Then through the pipe string with process fluid a plug is pushed with breaking the shear bolt and shifting the sleeve inwards the tube with opening filter openings and sealed cut-off of the jet nozzle. Residues of sandy mix are washed from the horizontal borehole by injection of process fluid to the pipe string and rotating the string in open horizontal borehole from the wellhead to the bottomhole. Before connection of the pipe string washing of the open horizontal borehole is made within one cycle with three-time treatment per length of one pipe until the funnel reaches the bottomhole of the open horizontal borehole. Then the pipe string is removed to the surface.

EFFECT: improvement of the method efficiency.

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