Demulsification of water-in-oil (W/O) emulsion via microwave irradiation: An optimization

The formation of water-in-crude oil emulsion creates many problems in petroleum industry such as decreasing the oil recovery efficiency, high pumping cost, and piping corrosion, which needs to be treated before processing. Microwave irradiation was employed to demulsify the water-in-oil (W/O) emulsion, which encountered in refinery industries. Three types of crude oils consisted of heavy and light crude oil used in this study to compare the effectiveness of microwave and conventional heating. The optimal conditions for microwave irradiation were determined by response surface methodology (RSM) for each crude oil. Correlation analysis of the mathematical regression models indicated that quadratic model could be employed to optimize the microwave irradiation in each crude oil. The optimal conditions for crude oil A were microwave power of 714 W, time processing in microwave irradiation of 2.53 min with 0.15 wt% of demulsifier and the percentage yield of water separation was 45.00%. While for crude oil B, the maximum yield of water separation predicted through this model was 64.07% at 692 W in 2.56 min. In crude oil C, the maximum yield of water separation predicted through this model is 38.03% at microwave power 767 W in 2.50 min with 0.14 wt% demulsifier.   Key words: Demulsification, water-in-oil (W/O) emulsion, optimisation, response surface methodology.