Enhancing surfactant desorption through low salinity water post-flush during Enhanced Oil Recovery

Low Salinity Water (LSW) incorporates in surfactant Enhanced Oil Recovery (EOR) as a pre-flush is common practice aiming to reduce the formation salinity, which affects adsorption. However, field implementation, adsorption of unavoidable, so creating scheme that detaches trapped equally essential. In this study, LSW was candidate enhance desorption surfactant. solely formulated from NaCl (1 wt.%), Sodium Dodecylbenzene Sulfonate (SDBS) chosen primary at its critical micelle concentration (CMC, 0.1 wt.%). It found injecting post-flush achieved up 71.7% SDBS lower interfacial tension against oil (31.06° API) 1.3 mN/m hence bring total Factor (RF) 56.1%. 4.9% higher than when and 5.2% greater conventional flooding (without LSW). Chemical analysis unveiled salinity reduction induces Na + ion substitution onto pore surface resulting an increment desorption. The study further conducted numerical simulation upon history matched with core-flood data reported previously. By introducing after injection, 5.6% RF increased comparison other schemes. proposed resolved problems adsorbed EOR, improve economic viability EOR.