METHOD FOR DEVELOPING DEPOSITS OF HIGH-VISCOSITY OIL AND NATURAL BITUMEN Russian patent published in 2022 - IPC E21B43/24 E21B43/22 C09K8/592 E21B7/04 E21B49/00 

FIELD: petroleum industry.

SUBSTANCE: method for developing deposits of high-viscosity oil includes injecting the boreholes with steam and a composition of reagents for the chemical conversion of heavy oil and collecting the reservoir fluids. The composition of reagents for the chemical conversion of heavy oil includes a nanoscale catalyst based on a mixed transition metal oxide, wherein the metals are selected from the following group: Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, hydrogen-donor petroleum solvent (nefras) C4-155/205 and an alcohol-alkaline composition constituting a solution of sodium hydroxide in ethyl alcohol with a concentration of 0.1 to 20% wt. The reagents in said composition are contained in the ratio of nanoscale catalyst based on a mixed transition metal oxide : nefras C4-155/205 : alcohol-alkaline composition 1 to 30% wt. : 98 to 50% wt. : 1 to 20% wt. Horizontal production boreholes with a distance of 250 to 350 m between the wellbores are drilled in the deposit, or pre-drilled ones are used. All said wells are subjected to two cycles of cyclic steam stimulation; in the third cycle of cyclic steam stimulation, the above composition of reagents for the chemical conversion of heavy oil is added to the injected heat carrier, simultaneously switching the horizontal borehole, located in the centre of the layer-uplifted deposit above the level of other production boreholes in structure, to injection. Said borehole is used for constant injection of the heat carrier, and the reservoir fluids are collected through the other production boreholes. Herein, steam at a temperature up to 350°C is used, the volume of injection of said composition of reagents for the chemical conversion of heavy oil is calculated individually for each borehole based on the filtration and capacity properties of the reservoir and the penetration of the borehole in the oil-saturated reservoir, and the composition of the most effective catalyst and the concentration of reagents in the composition are determined based on laboratory studies of oil of a specific deposit.

EFFECT: increase in oil recovery of the deposit due to the improvement of oil displacement and increase in the sweep area of the deposit.

1 cl, 2 dwg, 3 tbl