Worldwide, excellent efforts have been created to enhance the recovery of oil. Over the previous century, Nano technology features in EOR have been the focus of attention.The introduction of nanotechnology started in the late 1980s and was created by rearranging atoms and molecules to synthesize fresh nano-materials. Based on the small partice size of NPs' (1-100) nm, the nanomaterial's optical, thermal, chemical and structural properties differ completly from those shown by either its atoms or bulk materials. Nanoparticles and surfactants assist each other stabilize and maintain stable emulsions. Furthermore, it is clear that surfactants contribute to the stability of nanoparticles and emulsions in order to reduce IFT and change the rock wettability toward water.
The main objective of this study is to investigate the effects of nano particles and surfactant on interfacial tention, fluid stability, and wettability index of carbonate reservoirs. Two key parameters were examined: silica nano particles and silica nano particles with Sodium Dodecyl sulfate (SDS) as an anionic surfactant. Surface tension test was done for the surfactant to find critical micilles concentration, Interfatial tension test were done for fluids containing different SiO2 concentrations, dynamic light scattering (DLS) method was used to find the stability of nanoparticles in aqueous solution, and wettability test was done for core samples to investigate the effect of nano-surfactant on rock wettability. The results show that the CMC value for SDS was 0.158 wt% and increased SiO2 concentrations can reduce IFT values. Also, silica NPs' and SDS could improve the carbonate rock wettability to be more water-wet.