William M. McCardell Professor in Chemical Engineering Rice University Houston, TX, United States
Abstract: Nonionic surfactants are increasingly being applied in oil recovery processes due to their stability and low adsorption onto mineral surfaces. However, these surfactants lead to the production of emulsified oil, which is undesirable as they cause several challenges that add high costs to the recovery process. Additionally, after oil-water separation, the produced water must be below 35 ppm before being discharged into the environment. This work examines the demulsification of crude oil mixed with a nonionic surfactant, SURFONIC® L24-22. After sitting under gravity for several months, the produced oil separates into a neat crude oil (top), a viscous oil-rich emulsion (middle), and a water-rich O/W emulsion (bottom). We first examine the effectiveness of applying a conventional heating treatment. Demulsifification is examined using NMR. Subsequently, a nanofluid composed of functionalized magnetic nanoparticles are used to further separate crude oil from the water-rich phase. The application of both heating and nanofluid treatment to treat the middle and the bottom emulsion produced oil layers can be used to meet economic and environmental goals for oil recovery operations.
