Effect of polymer solution viscoelasticity on residual oil

In this article, the oil displacement efficiencies of viscoelastic HPAM solution and viscous glycerin solution are studied by flooding at visual microscopic glass models. Also, the effect and mechanisms of the viscoelasticity of HPAM solution and glycerin solution on the displacement of residual oil in dead-ends are studied, and the relationship between the elasticity of HPAM and oil displacement efficiency is given. The results of microscopic oil displacement experiments indicate that the displacement efficiency of HPAM solution flooding and glycerin solution flooding gradually increase with the increase in a viscoelasticity of HPAM solutions and the viscosity of glycerin solution. However, for HPAM solution flooding, the displacement efficiency is always higher and residual oil saturation lower than that of glycerin at the same viscosity, same capillary number and at the same oil saturation after water flooding.