Research progress on stability and demulsification mechanism of crude oil emulsions
FENG Cheng, ZHENG Huan-ling, WANG Jia-ning, SONG Fan-yong, LI Tian-yuan, FU Xiao-wen, HUANG Yu-jie, ZHANG Wen
Qilu University of Technology, Ecology Institute of Shandong Academy of Sciences, Shandong Province Key Laboratory of Applied Microbiology, Jinan 250103, China
Abstract：Crude oil emulsion is a complex oil-water system produced in the process of crude oil exploitation. The natural interfacial active substances and added polymers increase the stability of the emulsion. Gum and asphaltene are considered as the main stabilizers of the oil-water emulsion. Chemical demulsification is a method to separate oil from water by adding demulsifier to emulsion, but the mechanism of demulsification has not been confirmed. The influence mechanism of interfacial active substances in crude oil emulsions, including interfacial film, interfacial tension, gel, asphaltene and so on, on the stability of emulsions was reviewed. The development status and trend of demulsifiers and their effects on emulsions were discussed. At present, the main research directions of demulsifiers include modification and combination, research and development of polyquaternary ammonium salt, polyethers and other demulsifiers The research status of demulsification mechanism and the future research direction of demulsification mechanism and demulsifier were prospected.
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