Numerical analysis of SiO2-SDS surfactant effect on oil recovery in sandstone reservoirs

Abstract

Currently, the demand for using nanoparticles (NPs) in Enhanced Oil Recovery (EOR) is very high. The use of NPs can drastically benefit EOR by changing the rock wettability, improving the mobility of oil phase and decreasing the interfacial tension (IFT) between oil/water. Most of the previous studies were experimentally conducted and limited to specific operating conditions. This study contributes to the understanding of nanoparticle behaviour at altered operating conditions. In this investigation, a 3-D numerical model of silica nanofluid proposed for EOR is presented. A numerical model of core-scale sandstone was developed using Computer Modelling Group (CMG)-STARS simulator. The developed model was well validated against an experimental data. Then Silicon Dioxide (SiO2) and Sodium Dodecyl Sulphate (SDS) nano-surfactant mixture were injected with different concentrations. The optimum concentration of SiO2–SDS solution was obtained at 0.15 wt% with the highest recovery factor of 71.86% achieved. Moreover, SiO2–SDS solution injection rate and temperature were investigated and it was found that the optimum operating conditions of injection rate and temperature were 2 cc/min and 60 °C with the highest recovery achieved. In addition, a heavy crude oil showed a significant increment of oil recovery compared with a light crude with 3.13% and 0.6%, respectively. The intermediate viscosity of used crude oil had the highest oil recovery increment.