Optimal polymer slugs injection profiles

The graded viscosity banks technology (tapering) for polymer flooding is studied for several different models of mixing zones behavior. Depending on the viscosity function the limiting polymer injection profile is rigorously derived for the transverse flow equilibrium model, for the Koval model and for the Todd-Longstaff model. The potential gain in the polymer quantity compared to the profile with a finite number of slugs is numerically estimated.