Study on the Kinetics of Formation Process of Emulsion of Heavy Oil and Its Functional Group Components

Abstract

The key to the cold recovery technology of heavy oil is the efficient emulsification and viscosity reduction of heavy oil under formation conditions. The dynamic model of heavy oil emulsification process was established by conductivity method for the first time. The change in water phase conductivity during emulsification conforms to the second-order rate equation. In addition, an investigation was conducted on the effects of functional group composition, emulsifier concentration, temperature, pH and stirring speed on the emulsification rate of heavy oil. The results show that the conductivity method effectively evaluates the emulsification rate. Acidic and amphoteric fractions exhibit higher interfacial activity, larger emulsification rate constant and faster emulsification rate. With the increase of emulsifier concentration, the emulsification rate constant first rose and reached its maximum value at a concentration of 0.05 mol/L before decreasing. The activation energy of the emulsification process is 40.282 kJ /mol, and increasing temperature benefits the emulsification rate. Higher pH levels and stirring speed indicate a faster emulsification rate. The study of dynamics law provides theoretical guidance for an in-depth understanding of the mechanism and application of cold recovery technology for heavy oil.