MATHEMATICAL MODELING OF OIL DEWATERING BY ELECTROSTATIC COALESCENCE: A SEMI-EMPIRICAL MODEL APPLIED TO PILOT-PLANT AND INDUSTRIAL SCALE

In this work, a semi-empirical mathematical model is proposed to simulate electrostatic coalescence, which is used for crude oil dehydration. The model is based on asymptotic analytical solution of the population balance equation of water droplets applied to water droplets distribution in a coalescer. This model considers that the water content in treated oil (BS&Wo) is a function directly related to the fragmentation and aggregation rate coefficients in dropwise electro-coalescence, while the ratio of these coefficients is a function of physical properties and operating variables. The model shows a good prediction of BS&Wo  (with R2  above 0.8) under different electro-coalescence conditions (at pilot plant and industrial scale) when considering the API gravity of oil. Sensitivity analysis of the parameters in the model revealed that oil viscosity has a strong influence on BS&Wo , as confirmed experimentally.