WELL INHIBITING METHOD FROM ASPHALTENE-RESIN-PARAFFIN DEPOSITS Russian patent published in 2020 - IPC E21B37/06 C09K8/52 

FIELD: oil, gas and coke-chemical industries.

SUBSTANCE: invention is intended for use in oil producing wells, operation of which is complicated by formation of asphaltene-resin-paraffin deposits - ARPD in a flow column and pump equipment. Prevention of formation of deposit under the invention is carried out by two-stage pumping into productive heterogeneous permeability oil reservoir technical liquids. At the first stage, a gel solution with a paraffin formation inhibitor is pumped into the formation. At the second stage, a gel converter is injected into the formation, having a higher viscosity than the gel solution and the ARPD inhibitor. Owing to high viscosity, the gel converter will mainly penetrate into the high-permeability zone of the formation and for a certain period of time it preserves the gel solution with the ARPD inhibitor in the interlayers. After the well is put into operation, an ARPD polymerisation inhibitor enters the production string from interlayers with low permeability, where the gel solution converter is not available due to its high viscosity. After definite and calculated time under action of pressure drop, gel converter loses its strength properties, breaks down and opens filtration channels for ARPD inhibitor introduction into well from highly permeable interlayers.

EFFECT: technical result is higher efficiency of method due to uniform and longer supply of reagent to well, prevention of paraffin formation in column of lifting pipes and bottom-hole pump.

1 cl, 1 dwg