Emulsified oil foam for improving the flowability of heavy oil in wellbore under high salinity environments

Abstract Emulsified oil foam was investigated to improve the flowability of heavy oil under high salinity environment of 23 × 10 4  mg/L. Sixteen foaming agents were used to determine an applicable formulation. The factors affecting the formation and stability of the emulsified oil foam were evaluated, including oil viscosity, oil–water ratio, foaming agent concentration, stirring rate and time, and temperature. The microgram of emulsified oil foam was analyzed by polarizing microscope. The results showed that stable pseudo-emulsion film was built. The considerable dynamic viscosity-reducing rates in different depth in wellbore were obtained according to pressure differential method in long tube physical simulation experiments.