OIL PRODUCTION METHOD Russian patent published in 1999 - IPC

FIELD: oil production industry. SUBSTANCE: method can be used in recovery of oil of any fractional composition at any stage of deposit development and also in development of deposits which where earlier developed by method of artificial flooding. According to method, producing wells are drilled from day surface. Their bottom holes are located by 300-500 m deeper than floors of oil bed. Wells are equipped with two pipe strings. External pipe strings are for gas, internal pipe strings are for oil. Gas pipe string is lowered down to bottom-hole of well, and in its lower end it has openings for overflow of oil into it. Mounted on oil pipe string is down-hole pump with gas anchor. Oil pipe string is lowered down to level which is higher than bottom-hole of well. Subsurface gravitational separators are created. They divide oil-gas mixture from bed into oil and gas products. Output capacity of subsurface pumps is selected so that oil column in well does not create counterpressure brought to bear on bed. Application of aforesaid method ensures higher output capacity on account of utilizing bed energy. EFFECT: higher efficiency. 4 cl, 1 dwg