Modeling of viscoelastic polymer flooding in Core-scale for prediction of oil recovery using numerical approach

Abstract

Prior works have proposed mathematical models to evaluate flow of viscoelastic polymer through porous media. However, some of the effects and phenomena have not been considered or have not been well investigated yet such as thermal effects, effective concentration, dispersion and diffusion, salt effects which reduce solution viscosity and tend to increase amount of polymer adsorption on rock surface, equivalent shear rate in porous media, permeability reduction of aqueous phase and elastic behavior which leads to more piston-like displacement and reduction in residual oil saturation. The aim of this study was therefore to improve existing models and presenting a mathematical model which considers all mentioned phenomena to estimate oil recovery of core-flood experiments in process of hydrolyzed polyacrylamide flooding as a tertiary stage of enhanced oil recovery. Initially, laboratory data and model were used to optimize rock properties and model parameters; then model was applied to predict oil recovery of other core-flood conditions with various residual oil saturation. The model was found highly reliable when compared to experimental data and material balance. Displacement performance of core-flood tests could be estimated by presented model. Subsequently, experimental costs will be decreased significantly. Least requirement of experimental data and simplicity are the advantages of model over compositional model of polymer flooding in UTCHEM simulator.