Effects of the particle concentration on the electro-dehydration of simulated SAGD produced ultra-heavy oil

Abstract

Steam Assisted Gravity Drainage (SAGD) produced ultra-heavy oil contains large amounts of solid particles which significantly stabilize the emulsions. These emulsions are highly undesirable in petroleum transportation and the refining process. The effects of sand particle sizes and concentrations on electro-dehydration efficiencies were experimentally assessed with simulated SAGD produced emulsions. The results showed that the electro-dehydration efficiencies, which are defined as the ratio of the loss of the water content and the initial water content in the emulsions, first increased and then decreased with increasing sand particle concentrations. In addition, the dehydration efficiency of large particle emulsions was higher than that of small particle ones. The dehydration power, which was presented in a normalized way of power per unit volume, of large sand particle emulsions was higher than that of small sand particle ones. At high concentrations, the small particle emulsions were well stabilized, which led to a steady dehydration power. High-voltage and high-frequency electric fields can efficiently break up the thick particle films covering the water droplets of the SAGD produced oil and dehydrate the oil better than the traditional alternating current/constant direct current fields. The outcome of this work is potentially useful in the design of compact and efficient oil–water electro-dehydration devices for ultra-heavy crude oil with a high sand content.