Numerical simulation of ph-sensitive polymer injection as a conformance control method

Polymers such as polyacrylic acid hydrogel are microgel solutions that exhibit large viscosity changes as their pH increases above a critical value. The Huh-Choi-Sharma rheological model developed previously for pH-sensitive polymer was successfully implemented in the commercial GEM-GHG reservoir simulator and tested. With the simulator’s ability to model geochemical reactions and to predict fluid pH, the polymer viscosity model allowed estimation of polymer solution viscosity based on the pH, ionic strength, shear rate and polymer concentration of an aqueous solution. Simulations of linear and radial geometry floods were carried out to test the effectiveness of using high-viscosity fluids and pH-sensitive polymers as an in-depth conformance control method in oil reservoirs.