IN-SITU COMBUSTION METHOD (VERSIONS) Russian patent published in 2015 - IPC E21B43/243 

FIELD: oil and gas industry.

SUBSTANCE: group of inventions is related to production of viscous hydrocarbons from the underground collector. The in-situ combustion method intended for reduction of oil viscosity includes the following operations: usage of at least one producer having in essence a vertical section descending to the above reservoir and having a section of horizontal branch coupled by fluid to the above vertical section and passing outside horizontally from it, at that the above section of the horizontal branch is completed relatively low in the reservoir; usage of at least one injector in the area between the opposite ends of the above horizontal branch with offsetting from the above horizontal branch placed in essence directly over the above section of the horizontal section and in vertical adjustment with it for the purpose of oxidizing gas injection to the above reservoir over the above section of the horizontal branch and to the are between the opposed ends of the above section of the horizontal branch; injection of oxidizing gas through the above at least one injector and initiation of hydrocarbon combustion in the above reservoir close to the above injector with creation of at least one or several combustion fronts over the above section of the horizontal branch, at that one or several combustion fronts lead to reduced viscosity of oil in the above reservoir and to oil flowing down to the above section of the horizontal branch; arrangement of conditions for accumulation of high-temperature gaseous combustion products with the above low-viscous oil in the above section of the horizontal branch; lifting of the above high-temperature gases and oil to the surface; separation of oil and high-temperature gaseous combustion products near the horizontal well bottom or at the surface.

EFFECT: increased oil recovery standard rate, improved oil quality, potential operation of reservoirs inaccessible directly from the surface at moderate costs of the development method.

21 cl, 5 dwg, 2 tbl