OIL DEPOSIT DEVELOPMENT METHOD Russian patent published in 2010 - IPC E21B43/20 

FIELD: oil and gas industry.

SUBSTANCE: method involves drilling of deposit with injection and production wells, subsequent pumping of fringe of carbon dioxide and water through injection wells and oil withdrawal through production wells. Formation is conditionally divided into upper and lower parts. Pumping of fringe of carbon dioxide with further pumping of working agent-water is performed selectively with various concentration of carbon dioxide and various values of dynamic viscosities of oil for upper and lower parts of formation. Dynamic oil viscosity in upper part of formation is set smaller than in lower one owing to large pumping volumes of carbon dioxide to it. Pressure value at pumping is set larger for upper part than for lower one divisible by gravitational forces in those parts from analytical expression.

EFFECT: increasing oil withdrawal coefficient owing to simultaneous increase of displacement efficiency, suppression of viscous instability and suppression of gravitational oil and water segregation.

2 dwg