DEVELOPMENT METHOD OF PRODUCTIVE LOW-PERMEABLE BED Russian patent published in 2020 - IPC E21B43/18 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, in particular, to production of oil from productive low-permeable formations. Method includes pumping after pressure formation pressure drop to preset value or lower through the well of displacing agent in gaseous state under pressure, providing maximum possible radius of piston displacement of formation product to point of phase transition of gaseous state into liquid, determined by thermobaric formation conditions, with further transition to mixing displacement mode, wherein liquid pumping in gaseous phase and product extraction is carried out in cyclic mode. Prior to operation of the well, core samples from this reservoir are analyzed to determine the boundary temperature of the formation product, above which the percentage content of saturated hydrocarbons in the formation product increases, as well as determination of preset pressure value, at which at temperature of bottomhole formation zone heating there is a phase transition of light fractions of formation production and/or bound water, which is in product of formation, into gaseous state – steam and back into liquid. After that, heat exchanger is lowered into horizontal section and/or section with ascending face of well, through which heat carrier is pumped with temperature not less than boundary temperature. Wellhead product displacement to well bottom is provided by vapors of light fractions and/or water heated by heat exchanger, and after temperature drop under effect of vacuum created at phase transition of vapors back to liquid state, in the bottomhole zone of the well a network of cracks enlarging the formation coverage is formed.

EFFECT: high content of saturated hydrocarbons of the extracted product and an increase in the oil recovery factor owing to thermal action on the bottomhole formation zone.

1 cl, 1 dwg