METHOD FOR DEVELOPMENT OF HIGH-VISCOUS OIL DEPOSIT WITH CYCLIC STEAM SOAKING Russian patent published in 2018 - IPC E21B43/24 E21B43/267 E21B43/27 

FIELD: oil industry.

SUBSTANCE: invention relates to oil deposits development. Method for developing a high viscosity oil reservoir by steam cycling involves drilling a vertical well into high viscosity oil pools, fastening a vertical well with a casing string, casing perforating in the production formation interval, pumping through the well into the productive reservoir of the combined-cycle heat transfer medium, launching the tubing string with the pump into the well, and selecting the heated products from the well. Perforation in the interval of the productive formation, folded by carbonate rocks, is produced by a hydro-sandblast perforator with the formation of perforations with a diameter of 20 mm. After that, a proppant foam acid fracturing of the formation is carried out with the formation of a fracture by injecting a gelled fracturing fluid, followed by its development and fastening in five stages alternating batches of foam acid in equal volumes and foam acid with the addition of a proppant mixture of 2 tons each in each stage consisting of 12/18 mesh coarse proppant and 12/16 mesh cylindrical proppant in a percentage ratio of 60/40, at each subsequent stage, the concentration of the proppant mixture is increased stepwise from 200 to 600 kg/m³ in increments of 100 kg/m³, and the concentration of acid in the foam is not less than 16 %. To reduce heat losses at the beginning of the steam cyclic action, the well is warmed by circulating the steam until the condensate is removed from the return line, a pipe string with a bottom-up non-return valve, a locking support of the plug-in rod-type pump, a by-pass valve, a packer is lowered into the borehole, a pipe string is placed in the well, so that the packer is in front of the roof of the upper part of the productive formation, then the rod-type plug-in pump is lowered into the column of pipes on the rod column and fixed in the lock support. After that, the well is pumped in a volume of 40 tons per day for 14 days, after which the well is closed and kept for 14 days for impregnation, then the heated high-viscosity oil is withdrawn. After lowering the production rate to a cost-effective level for a given well, the steam injection cycles and the selection of the heated high-viscosity oil are repeated.

EFFECT: technical effect: increase in the coverage of the deposit, increase in the efficiency of the steam-thermal effect on the reservoir, increase in the selection of the heated high-viscosity oil after the steam cyclic action, elimination of overheating of the upper part of the reservoir, and reduction of heat losses along the well bore.

1 cl, 3 dwg, 1 tbl