Perspectives of Foam Generation Techniques and Future Directions of Nanoparticle-Stabilized CO2 Foam for Enhanced Oil Recovery

Global demand for energy is increasing day by day rapidly as a result of the population, industrial, and economic growth of developing countries, especially in emerging market economies. Hence, to meet this growing and continuing global crude oil demand, innovative enhanced oil recovery (EOR) techniques are required to emerge, and currently, implemented techniques need to be revisited and optimized to recover more residual oil trapped in the reservoirs. Among different chemicals, foam has good mobility control in the oil recovery method. Nowadays, the study on the stability of foam is an utmost interest for petroleum engineers to find a way to obtain stable foam for application in EOR. In this review, the basics of foam and its preparations, properties, application, and some special applications mainly in the oil industry have been depicted to convey an idea of the degree of foam research in EOR. Basically, this review will provide a detailed discussion on the applications of foam in oil recovery and some short ideas that can be applied in the near future for nanoparticle (NP)-assisted stable CO2 foam flooding in EOR. Increasing the NP concentration initially improved foam stability because a higher number of NPs participated in strengthening the gas bubble and initially increased oil recovery as a result of the formation of more stable foam. The polymer-coated, nanoclay-surfactant-stabilized foam and surface-modified silica nanoparticles have exceptional foaming ability and foam stability at high temperatures, making them suitable for the production from heavy oil reservoirs. Some other nanoparticles, like Al2O3, ZrO2, TiO2, Fe2O3, and NiO, have also been used for enhancing foam stability by preventing liquid drainage from lamella. Also, NP-stabilized CO2 foam flooding can enhance oil recovery by 10-15% after secondary recovery by creating a more homogeneous gas front for better mobility control.