Experimental investigation and simulation for hybrid of nanocomposite and surfactant as EOR process in carbonate oil reservoirs

Abstract

Numerous studies have been presented in the literature on the effect of the combination of nanoparticles and surfactants on enhanced oil recovery (EOR). In this study, we investigated the synergistic effect of synthesized Nanocomposite (ZnO@PAM) and surfactant on enhanced oil recovery by performing zeta potential (evaluation of chemicals stability in the aqueous phase), adsorption, wettability alteration (evaluation of the quantitative and qualitative wetness), and interfacial tension testes. In addition, to better understand how the fluid moves after chemicals flood in the porous medium, the Cartesian model was developed in CMG-STARS. Besides, this model is valid because of the history match of the oil recovery data, water cut data, and relative permeability curves. The Nanocomposite was physically synthesized from polyacrylamide polymers and zinc oxide nanoparticles under reflux conditions. The CMC surfactant point was obtained by examining various parameters (pH, density, electrical conductivity, and IFT). In the next step, we prepared nano-surfactant solutions (Nanocomposites with different concentrations of 100 ppm, 200 ppm, 500 ppm, and 1000 ppm + Surfactant (CMC)). By investigating the results of the adsorption and zeta potential tests, it was observed that the combinations of Surfactant and NCs have a positive effect on each other (increased nanoparticle stability and decreased surfactant adsorption on the carbonate rock surface). The Surfactant and Nano-Surfactant reduced the IFT from 29.16 to 0.176 (mN/m) and 1.354 (mN/m), respectively. In addition, the Surfactant at CMC and Nano-Surfactant (Surfactant (CMC) + NCs (500 ppm)) improve the contact angle in carbonate rock from 145.86 to 64° and 12.79°, respectively. After the core flooding by Surfactant and hybrid of NCs and Surfactant, we saw an increase of 17.94% and 30% in oil recovery compared to seawater floods, respectively. Furthermore, we observed the effect of mobility control and reduction of the fingering phenomenon after the flooding of chemicals by analyzing the simulated fluid distribution. By constructing the model in the core dimensions, we were able to get a good history matching from the laboratory data. Moreover, the mobility ratio after simultaneous flooding of NCs and surfactant compared to seawater decreased from 13.354 to 1.86, respectively. In addition, according to the fluid distribution pattern (one of the simulator outputs) the fingering phenomenon, was delayed after flooding the hybrid of NCs and surfactant. The positive effect of this type of chemical compound on mobility control and the fingering phenomenon has caused increased oil recovery. This study's findings can help to understand better how hybrid chemicals perform on improved oil recovery.