Evaluation of alkaline treated fly ash as a demulsifier for crude oil emulsions

The formation of crude oil emulsion is a serious challenge in the petroleum industry as it can corrode upstream equipment and also cause catalyst poisoning in the downstream. Thus, efficient and effective water removal from the emulsion becomes very necessary while substantial water removal can be achieved by using suitable demulsifiers. In this study, the alkaline treated fly ash (TFA) was tested as a potential demulsifier for crude oil emulsions encountered during hydrocarbons production. The water-in-oil emulsion was prepared and the demulsification activity of various TFA concentrations (1%, 3%, 5%, and 7%) was performed at a temperature of 75C. Likewise, the demulsification exercise of the blank sample (emulsion free of TFA) was conducted at the same temperature. Optical morphology and rheology tests were conducted before and after demulsification. Experimental results showed that the TFA can effectively break the naturally occurring emulsifiers in the emulsion and separate oil and water into phases. Each concentration of TFA applied was able to destabilize the emulsion and remove considerable amounts of water. However, the 7% TFA exhibited the highest water removal with a demulsification efficiency of 93%. Optical electron microscopic images exhibited the morphology of emulsion before and after the demulsification test. Results of the rheology demonstrated that the TFA reduced the viscosity of emulsion considerably indicating the collapse of emulsifying substance and coalescence of water droplets.