Experimental studies on the effect of electrostatic boundary conditions and frequency on the performance of a trigrid electrostatic coalescer

Abstract

In this work, we explore the effect of electric field distribution and incorporating two different frequencies in two different regions of a trigrid coalescer on the electrocoalescer efficiency. Specifically grounding water at the bottom of the coalescer is found to be effective. The effect of frequency on emulsion breakup is essentially due to chaining tendency of water droplets at high frequencies. The reason for this could be reduced electrostatic force between drops at higher frequencies due to higher capacitance of interstitial oil film between two droplets. Moreover, at low frequencies significant bouncing of drops from interface is observed, leading to lower separation rates.