Investigation of synergistic effect of nanoparticle and surfactant in macro emulsion based EOR application in oil reservoirs

The present paper deals with the characterization of oil in water (O/W) emulsion stabilized by the synergistic effect of surfactant and nanoparticle for their application in enhanced oil recovery (EOR). The emulsions have been formulated using n-decane and paraffin oil, silica nanoparticle and two different surfactants, viz., anionic sodium dodecyl sulfate (SDS) and cationic cetyl trimethyl ammonium bromide (C-TAB). The nanoparticle shows a synergetic effect in presence of surfactants which prevents the coalescence of dispersed oil droplets and lowers the interfacial tension (IFT) at the oil-water interface. The stability of emulsions was evaluated by particle size distribution, creaming behaviour, zeta potential and phase behaviour. The viscosity of emulsions remains stable at wide range temperature indicating thermal stability. The viscoelastic study indicates that the emulsions behave as a gel-like structure with a higher value of storage modulus (G') than loss modulus (G"). The addition of polymer leads to improvement in viscosity and stability of the emulsion, proving its usefulness in the reservoir for recovery of heavy oil. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.