A visual study of the breakdown of emulsions in porous coalescers

Water‐in‐oil coalescence in micro‐nanofiber composite filters

“…This result is consistent with literature (Voyutskii et al, 1955;Hazlett, 1969a;Moses and Ng, 1985;Basu, 1993) where the optimal performance is reported for high wettability fibers. Table 2 summarizes the calculated separation efficiencies (E) and quality factors (QF) obtained for the five filter media as defined by Eqs.…”

“…Many attempts have been made to determine the critical velocity defined as the velocity at which the effluent concentration of the dispersed phase exceeds a fixed value (Sareen et al, 1966;Spielman, 1968;Fahim and Akbar, 1984;Othman et al, 1988;Š ećerov Sokolović et al, 1997). Moses and Ng (1985) and Viraraghavan et al (1997) observed that high operational temperatures are preferred for the coalescence process. Many results show that the separation efficiency is influenced by the filter bed depth.…”

Product‐oriented process synthesis and development: Creams and pastes

“…A zeta potential of about ᎐40 to ᎐100 mV generally corresponds to a stable emulsion, but experimental testing is rec-Ž . ommended Moses and Ng, 1985 . Since it is often impractical to conduct stability tests comparable in length to the product shelf life, accelerated tests, such as storage at elevated temperatures and repeated exposure to freeze-thaw cy-Ž . cles, are often used Breuer, 1983 . Conditions in commercial production can be different from the laboratory-scale experiments.…”

The effect of wettability on drop attachment to glass rods

“…The dispersed phase comes into contact with the surface of the glass rod due to the combined effect of the London-van der Waals force and the directed velocity of the fluid motion component. The collection and coalescence of dispersed phase droplets in contact with the rod depends on the wettability between the dispersed phase and the surface of the rod [16].…”

“…The wetting behavior of the water-in-oil or oil-in-water emulsions is considered to be important in determining the performance of the coalescence efficiency. Moses and Ng [16] visually observed a model porous media coalescer and determined that in the case of oil droplets in water the oil droplets adhere more to the oil nonwetting surface than to the oil wetting surface. This result has been explained by the effect of zeta potential values of the collector and the emulsion.…”