Oil Viscosity Impact on the Production of Pickering Emulsions

Pipeline transportation technologies for viscous oils are becoming increasingly important because of the limited upgrading capacity in remote areas and the prohibitive cost related to building additional capacity. Heavy oil emulsification offers an attractive alternative to dilution for long-distance pipeline transportation. Pickering emulsions (solid-stabilized emulsions) could offer additional benefits when compared to standard emulsification practices with surfactants. Relying on the known and controlled wetting behavior of iron particles, the role of the dispersed phase viscosity in solid stabilized oil-in-water emulsions was studied in this work. Silicon oils of viscosities ranging from water-like to one Pa-s were used in a standardized emulsification process. Emulsification in controlled conditions showed that the viscosity of the dispersed phase dampened the particle anchoring at the o/w interface, slowing down the emulsion stabilization. The role of the dispersed phase viscosity is hence a key design factor for a continuous emulsification process. Based on the emulsification results, a combination of dispersed phase viscosity and agitation time must be respected in order to produce a stable emulsion. A relation between the emulsified oil volume, the o/w viscosity ratio, mixing power density, and agitation time is proposed for the studied systems.