A critical review of main enhanced oil recovery mechanisms by considering recent applications of green and novel nanocomposites

There are various developments in the oil and gas industry, both from environmental and economic viewpoints, based on utilizing nanotechnology. Although many researchers work on the effects of multiple nanocomposites on different techniques, such as chemically enhanced oil recovery and asphaltene precipitation inhibition, comprehensive research should be done for green, and novel nanocomposites. Nanocomposites, especially green, and novel applications for crude asphaltene adsorption, asphaltene inhibition during natural depletion, and CO2 reduction and enhanced oil recovery are accurately reviewed in this paper based on the recent research. Different parameters for asphaltene adsorption effectiveness, such as nanocomposites specifications and asphaltene characteristics, have been evaluated based on numerous investigations. Moreover, wettability alteration and interfacial tension as two effective parameters enhanced oil recovery, and different methods such as contact angle, spontaneous imbibition, and zeta potential tests have been reviewed with their relevant measurement result in the presence of novel, and green nanocomposites. Furthermore, the application of various green nanocomposites at different conditions, such as compositions, pH, salinities, and their influences on oil recovery, and relevant obstacles nanocomposites have been studied based on the previous works. Based on the results, green nanocomposites such as ZnO/SiO2/Xanthan had better results in comparison with commercial nanocomposites such as SiO2 for altering effective mechanisms in a reservoir such as wettability alteration, interfacial tension reduction, and green nanocomposites had better results for making the final solution more stable. Using nanocomposites such as urea/ZnO/gamma-Al2O3 had better results compared to gamma-Al2O3, and tertiary recovery of 27.2 % was obtained in simultaneous water and gas tests. The findings of the current research would help to have a better understanding of the effects of novel nanocomposites and green nanocomposites on enhanced oil recovery mechanisms.