Separation of water-in-heavy oil emulsions using porous particles in a coalescence column

• Capillarity and wettability are applied in designing coalescence porous material.
• The water-saturated porous particles can merge water droplets in W/O emulsions.
• The study provides a new method for the separation of water-in-heavy oil emulsions.

In this study, the principle of capillarity and the mechanism of a wetting film in porous media are applied in designing coalescence media. Water-wet porous particles are used for the first time in a coalescing column to enhance the separation of water from water-in-heavy oil emulsions. Experimental results show that this type of particles can remain water-wet in an oil environment and can significantly enhance the coalescence of water droplets in water-in-heavy oil emulsions. The coalescing column test results show that the flow of the emulsion through the 10 cm coalescing column reduced water content from 44.37% to 21.54% at 80 °C, without using a demulsifier. The coalescing column can further reduce the water content beyond what was reached in gravity separation using a high dosage of demulsifier. At a fixed temperature of 80 °C, when the dosage of the selected demulsifier changed from 50 to 100 to 150 ppm, water content was reduced to 10.49%, 1.32%, and 0.64%, respectively, with the use of a 10 cm coalescing column. These results indicate that the effect of adding a coalescing column to water separation from water-in-heavy oil emulsions is significant, as compared to using only a demulsifier in gravity separation. More importantly, flow through the coalescing column could reduce the water content in the heavy oil to a very low level (<1.0%) and, at the same time, reduce the consumption of demulsifier.