Polymer fiooding is achieved by odding a certain amount of high molecular weight polyacrylamide to the injected water to increase the viscosty of the njected water, improve the oil-water current ratio, adjust the water injection profile, expand the swept volume. Since the viscoelosticity of the polyme molecule has a stretching and carrying effect on the ol fm ol droplets, the oil displcement efficiency is improved and the oil recovery eff ciency is improwed.

Specification