Microfluidic study of heavy oil emulsification on solid surface

Abstract

Sandpack experiments cannot fully describe the microcosmic mechanism of oil/water emulsification. In this study, we used a microfluidic chip that can generate a heavy oil drop on the surface to investigate its flow behavior under both surfactant flooding and water flooding conditions. We recorded the images of the dynamic processes by a microfluidic platform and analyzed the effects of different influencing factors on the shape of the emulsion droplet. The findings indicated that the heavy oil drop advances slowly along the solid surface during water flooding while it could be emulsified as a tadpole-shaped droplet by surfactant. The surfactant adsorption could lead to a decrease in the adhesion force and friction force. Experiments further demonstrated that the shape of the emulsion droplet is related with surfactant flow rate, thickness, and viscosity of heavy oil. This work presents detailed mechanisms for heavy oil emulsification at the pore scale.