METHOD OF DEVELOPING WATER-FLOODED OIL POOL Russian patent published in 2002 - IPC

FIELD: oil-producing industry, particularly, methods of development of sheet oil pool. SUBSTANCE: method includes drilling of vertical wells and side horizontal bores from vertical wells. Well pump is lowered into vertical wellbore, and oil is withdrawn from well to surface. In this case, vertical well is drilled. Producing formation is tapped by perforation. Oil from formation is withdrawn up to its depletion. Then side horizontal bore is drilled. In so doing, point of side tracking of horizontal bore is located below dynamic level of fluid in well. The same producing formation is perforated from side bore. Then double-acting pump is installed in vertical wellbore. Pump intake for oil is located above point of side tracking. Pump intake for water is situated below point of side tracking. Pump is provided with liner-packer combination. It is installed in interval from point of side tracking to roof of producing formation in vertical wellbore. Well is operated so that water coming together with oil from horizontal bore is injected into the same formation through vertical wellbore without its lifting to surface. Proposed method provides for reduction of investments in oil recovery due to combination of functions of producing and injection wells and return of a part of associated water back into producing formation for maintaining the formation pressure without lifting it to surface. EFFECT: higher efficiency. 1 dwg