The electrocoalescence technology has been applied widely in refineries to separate water-in-oil emulsion because of the high efficiency, fast and large throughput. Despite there are many successful and promising industrial applications, the design for more efficient and stable elereocoalescence is essential. High-voltage and high-frequency electrocoalescence need to be designed to avoid short circuit caused by the bridge of the chain between electrodes. Although high-voltage and high-frequency electrocoalescence have been proposed many years ago, it is not applied widely in refineries. In order to investigate the influence of operating parameters on coalescence and migration of water droplets in high frequency pulsed electrocoalescence process, the effects of water content, emulsifying strength and temperature for the electrocoalescence of the water drops in W/O emulsions formed by conducting oil and water under high frequency pulsed electric field were studied through microscopy experiment in this work. The results showed that the theoretical analysis on collision rate and dipole attraction corresponded with the experiment when the water content was low. When the water content was high, the dehydration became worse because of the formation of long water chain. As emulsifying strength rose, the collision rate increased and the dipole attraction decreased. Temperature-induced emulsifying strength minimization was most suitable for electroalescence. As the temperature rose, the Brown movement strengthened and the continuous phase viscosity and the resistance of film drainage decreased. These all enhanced the electrocoalescence.
Zhiqian SUN Yantao ZHOU Bochuan LIU Yan JIANG Zhenbo WANG?
. Effects of operating parameters on the electrostatic migration and coalescence of water droplets of W/O emulsion[J]. The Chinese Journal of Process Engineering, 2019
, 19(3)
: 597
-602
.
DOI: 10.12034/j.issn.1009-606X.218261
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