Abstract
In the Oil Industry, part of the extracted crude oil is commonly found in form of emulsions, mainly as water-in-oil (W/O) and oil-in water (O/W), emulsions, and more complex emulsions are less frequent but can also be found, such as water-in-oil-in-water (W/O/W) and oil-in-water-in-oil (O/W/O). These emulsions must be broken before the starting of the oil refining process because water generates operational problems like increasing crude viscosity, corrosion of equipment, piping and clogging of pumps and equipment, causing unscheduled production stoppages. O/W emulsions, can also be intentionally generated as a strategy to reduce the viscosity of very heavy crudes and facilitate their transport to the storage, and processing center. However, in any case, these emulsions must be broken before the crude is processed. Different technologies employing chemicals, electric fields, membranes, biological techniques, ultrasound and microwaves have been studied to favor the breaking of O/W emulsions. Microwaves have proven to be an excellent alternative to break emulsions quickly, efficiently, and with minimal energy losses. This paper review accounts for the research studies on the microwave-assisted breaking of W/O and O/W emulsions for oilfield applications with and without the simultaneous application of demulsifying chemicals. The possible mechanisms by which microwaves accelerate emulsion breakage, and their advantages for a more sustainable industry are also discussed.
Graphical Abstract
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Acknowledgments
The authors would like to thank their respective managers and their institution (Project number F.30730) for the facilities and support provided for this review.
Additional information
Notes on contributors
Heriberto Díaz Velázquez
Heriberto Díaz Velázquez was born in Tenango del Valle, Mexico, in 1983. After pursuing a M.Sc. in materials science at UNAM (Mexico, 2009), he finished a Ph.D. in chemistry at Ghent University (Belgium, 2014). He got a postdoctoral position at the Mexican Petroleum Institute, where he later obtained a position as a scientific researcher. His research focus has been focused on catalysis for sustainable processes such as CO2 transformation, pollutants adsorption by MOFs, and petroleum refining.
Diego Guzmán-Lucero
Diego Guzmán-Lucero was born in Nariño, Colombia in 1970. He received his Ph.D. from de National Autonomous University of Mexico (UNAM) in 2003. Then, he worked for 3 years as a postdoctoral fellow with Prof. Rafael Martínez-Palou at Mexican Petroleum Institute (IMP). In 2006, He joined IMP. His research interest focus on the ionic liquids and poly(ionic liquid)s applied to the petroleum industry: catalysis, corrosion, ionic polymers for water control, and enhanced oil recovery.
Rafael Martínez-Palou
Rafael Martínez Palou holds a B.Sc. in Chemistry from Havana University. He performed graduate studies in Chemical M.Sc. and Ph.D. at Instituto Politécnico Nacional in Mexico City. He received a postdoctoral position at IMP where he works as a researcher since 2002. He is involved in the development of bioproducts by sustainable transformations of biomass, and the synthesis and scaling of new organic compounds and polymers for chemical treatments and catalysts in the Petroleum Industry.