Investigation of liquid-electric separation properties following acidification in alkali-surfactant-polymer flooding

This study investigates the key factors influencing the emulsification of oil-water emulsions in alkali-surfactant-polymer (ASP) flooding wells using a high-pressure electric field separation approach. The research examines how oil-water emulsions respond to demulsification under high-voltage conditions and identifies the challenges associated with emulsion separation in oilfield operations. These findings provide valuable technical insights for optimizing the treatment of produced wastewater in oilfields. The results indicate that when sodium chloride concentrations exceed 3000 mg/L, the efficiency of electroseparation declines. Furthermore, introducing nanoparticles extends the time required for emulsion separation under an electric field. A critical threshold is identified when nano-ferrous sulfide concentrations surpass 0.05% and sodium chloride levels exceed 1600 mg/L, marking the limit for effective electroseparation. Additionally, an increase in colloid and asphaltene content negatively impacts the separation process. However, hydrolyzed polyacrylamide (HPAM) and heavy alkylbenzene sulfonate (HABS) exhibit a relatively small influence on the electroseparation efficiency of the emulsion.