DEVELOPMENT AND OIL RECOVERY IMPROVEMENT METHOD FOR INHOMOGENEOUS OIL POOLS Russian patent published in 2014 - IPC E21B43/22 C09K8/86 

FIELD: oil and gas industry.

SUBSTANCE: invention is related to the oil industry and can be used for the development and oil recovery improvement for inhomogeneous oil pools by waterflooding. In the development and oil recovery improvement method for the inhomogeneous oil pools including waterflooding with cyclic injection of a cross-linked alkali-polymer clayey quartz compound to the pool, wherein a water polymer solution cross-linked by chrome acetate is used as the polymer basis, at first the water solution of hydrolysed polyacrylamide (PAA) and chrome acetate cross-linker is injected, then the solution is flushed by water and a water suspension of a modified Lamco clay and quartz sand mixture is injected and then flushed by water, the above water solution comprises additionally caustic ash with the following concentration of the components, wt %: hydrolysed polyacrylamide PAA 0.01-0.30, chrome acetate 0.1-0.6, caustic ash 0.05-0.1, a ratio in the modified Lamco clay and quartz sand mixture.

EFFECT: improving oil recovery of the inhomogeneous and water-flooded pools at the late stage of development, reducing water cut of the product.

1 ex, 1 dwg