Sacrificing\nSurfactants to Improve Oil Recovery: A\nFluid Density Functional Theory Study

In the chemically enhanced oil recovery (CEOR) processes,\nheavy\ncomponents in crude oil, such as asphaltenes, adhere to reservoir\nrocks, significantly impeding crude oil extraction. Surfactants are\nfrequently utilized to improve oil recovery due to their ability to\nreduce interfacial tension (IFT) and modify surface wettability. Nevertheless,\nindiscriminate surfactant usage may result in resource wastage and\nhinder the attainment of optimal recovery outcomes. Therefore, it\nis urgent to accurately and efficiently screen out optimal surfactants\nsuitable for different oil fields. This work employs fluid density\nfunctional theory (FDFT) to investigate the competitive adsorption\nmechanism of surfactants and asphaltenes on rock interfaces. We examined\nthe impact of surfactants on asphaltene adsorption and determined\nthe optimal surfactant concentration and chain length for differing\nreservoir electrical properties and asphaltene compositions. Furthermore,\na comprehensive assessment of surfactants was conducted, considering\nboth performance and economic factors. The findings contribute to\na deeper comprehension of the displacement effect of surfactants on\nasphaltenes and offer scientific screening solutions for surfactants\nin oil recovery processes.