Smoothed particle hydrodynamic simulations of electro-coalescence in water–oil systems

Abstract

In the present work, the effects of electric fields in water-in-oil colloidal systems are studied numerically with the smoothed particle hydrodynamic method. Several simulations were carried out with the free-code DualSPHysics for a water–oil system with droplet-size distribution less than 120 μm were carried out with the free-code DualSPHysics. The system assumed the absence of surfactant agents and constant temperature. The initial droplet dispersion was generated with random positions using random numbers in the workspace with the boundaries as the upper and lower limits correcting the overlapping if it occurs. The emulsion was subjected to different magnitudes of electric fields from 700 to 2100 kV for the emulsified system with 2% of water and electric fields of 300, 500, and 700 kV for the emulsified systems with 5%, 10%, and 15% of water. The emulsions with 2% of water achieve a separation efficiency of 48% and 35% of the emulsified water with a field magnitude of 2100 kV for the evaluated systems. On the other hand, in the systems with 5%, 10%, and 15% of water, the process stream is always delivered under specifications, that is, a content of less than 0.5% BSW with separation efficiencies of 92%, 95%, and 97% of emulsified water in the system. The results show the efficiency of the separation process assisted by electric fields is a function of the percentage of the dispersed phase and of the magnitude of the electric field, concluding the method is 5%–10% reliable for emulsified water.