Research status and analysis of stabilization mechanisms and demulsification methods of heavy oil emulsions

Abstract One major challenge often encountered during the production and transportation of crude oil in petroleum industries is the formation of extremely stable emulsions. This problem is particularly present during the production of heavy oils where steam is used to reduce the viscosity of heavy oil or where submersible pumps are used to artificially lift the produced fluids. This review elaborates on the mechanism of the formation and stability of heavy oil emulsions, discusses the effect of natural surfactants (resins, asphaltenes, solid particles, etc) on the stability of heavy oil emulsions, and summarizes the prominent and sustainable technological and methodological developments in the demulsification of heavy oil emulsions from an economical and environmental perspective. Ionic liquids have been reported as efficient and environmental demulsifiers, and the latest research results on this topic are discussed. Microwave and ultrasonic demulsification methods have been reported to be effective in treating heavy oil emulsions and are also recommended as substitutes in the further development of demulsification technology for treating heavy oil emulsions.