METHOD TO PRODUCE HIGH-VISCOSITY OIL AND BITUMEN Russian patent published in 2015 - IPC E21B43/267 E21B43/24 

FIELD: oil and gas industry.

SUBSTANCE: method includes pad drilling of the upper, middle and lower well with vertical sections and horizontal bores placed in parallel to each other, installing electrodes and submersible centrifugal pump into the wells, heating reservoir with electric current through the installed electrodes, extracting heated high-viscous oil and bitumen by submersible centrifugal pump. Horizontal bores of the wells are drilled in direction of maximum stress σmax in rocks composing the reservoir. Along the whole length of horizontal in the upper well hydraulic fracturing is performed with longitudinal cracks and their further fixing with proppant agent made of current-conductive material. Vertical wells are drilled with crossing of initial and final sections in the upper well horizontal bore within the interval of hydraulic fracturing. To vertical wells, to the interval of crossing with the upper well horizontal bore electrodes are run down, and sucker-rod strings are used as the above electrodes. At the well mouth electrodes are connected to the electric substation, and then to the vertical section of the middle well a submersible centrifugal pump is run down at the pipe string. The reservoir is heated through horizontal bore of the upper well and heated high-viscosity oil and bitumen are extracted from the middle well horizontal bore through the pipe string by the submersible centrifugal pump. Upon completed workout of high-viscosity oil and bitumen are extracted from at the section between horizontal bores of the upper and middle well the electrodes are disconnected from the electric substation and removed from vertical wells, and from vertical section of the middle well the pipe string with the submersible centrifugal pump is removed. Then in horizontal section of the middle well hydraulic fracturing is performed with longitudinal cracks and their further fixing with proppant agent made of current-conductive material. Vertical wells are drilled additionally to crossing with initial and final sections of the middle well in the interval of hydraulic fracturing; to vertical wells in interval with their crossing with horizontal section of the middle well electrodes are run down and at well mouths electrodes are connected to the electric substation. The submersible centrifugal pump is run down to the vertical section of the lower well; the reservoir is heated through middle well horizontal bore and heated oil is extracted from the lower well horizontal bore through the pipe string by the submersible centrifugal pump.

EFFECT: improved efficiency of heating for the reservoir with high-viscosity oil and bitumen, increased coverage of the reservoir by thermal effect and uniform heating, increased yield of heated oil and improved reliability of the method implementation.

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