METHOD FOR EXTRACTING RESERVOIRS OF HIGHLY VISCOUS OIL OR BITUMEN Russian patent published in 2006 - IPC E21B43/24 

FIELD: oil extractive industry, in particular, extraction of oil reservoirs, possible use during extraction of highly viscous bitumen oil by means of thermal stimulation of bed.

SUBSTANCE: method includes drilling a vertical well, lowering and cementing a flow string, its perforation, lowering of tubing pipes, forcing in heat carrier and extracting highly viscous oil or bitumen. In accordance to invention, after drilling of vertical well, collector and thermal properties of beds opened by drilling are researched. Bitumen saturated and water saturated bed seams are selected. After that from vertical well a horizontal side borehole is drilled to open intermediate water seam in the cut of bitumen reservoir - for half of expansion of local water seam. Side borehole is cemented up to upper bituminous seam. Then perforated casing string is lowered into side borehole, perforation being done so that the number of perforation apertures is increased with withdrawal from vertical borehole of well, and vertical borehole is perforated in zones opened by drilling of bituminous seams. Tubing pipes are lowered into vertical well with packer, which is mounted below side borehole kickoff interval. Forcing of heat carrier is performed into side horizontal borehole, and extraction of highly viscous oil or bitumen - via vertical borehole. After extraction of productive zone between vertical and side horizontal borehole into side horizontal borehole a fringe of polyacrylamide is forced successively in volume of 0,1 of volume of heated productive zone and water. Water is forced until appearance of polyacrylamide in vertical borehole of well. After that forcing of heat carrier into side horizontal borehole is renewed. Extraction of highly viscous oil or bitumen is performed. Then heat carrier is forced through vertical well borehole or side horizontal borehole to provide for extraction of highly viscous oil or bitumen in adjacent extractive wells.

EFFECT: increased oil recovery of productive bed due to depth of heating and decreased thermal losses.

1 ex, 2 dwg