Injectability of Partially Hydrolyzed Polyacrylamide Solutions Improved by Anionic-Nonionic Surfactant in Medium and Low Permeability Reservoirs

Injectability of the polymer solution is a very important factor that determines effectiveness flooding for enhanced oil recovery. Here, medium and low permeability reservoir was taken as research object, effects relative molecular weight, concentration core on flow injection performance partially hydrolyzed polyacrylamide (HPAM) with without anionic-nonionic surfactant (ANS) were studied by indoor outcrop physical model experiments. It found influence HPAM related to permeability. When lower than 59 mD, resistance residual increased increasing concentration. High weight not conducive injectability solutions. The addition ANS beneficial in enhancing reducing critical value solution, which elucidated Hall curve derivative method. In presence ANS, pressure gradient decreased. believed improved reservoirs can be attributed decrease fluid viscosity competitive adsorption surface porous media. study provides new idea theoretical basis improving an application polymer/surfactant binary system reservoirs.