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

FIELD: oil-gas producing industry, particularly, methods of oil recovery from nonuniform formations at late stage of oil deposit development. SUBSTANCE: method includes combined injection of aqueous solution of polymer with alkali reagent through injection well and oil recovery through producing well. For polymer cross-linking, additionally injected into well is solution of aluminochloride with sodium bichromate and subjected injection of soda ash for formation of sediment with excess of aluminochloride. Prior to injection of polymer aqueous solution with alkali reagent, hydrochloric acid is injected into well. Alkali reagent is used as soda ash, caustic soda, water glass. EFFECT: creation of isolation shield with improved process parameters and prolonged effect for zones of formation with any permeability. 2 cl, 1 tbl