Prediction of oily water separation efficiency by fiber bed using new filter media property

Dunja Sokolović, Milica Hadnadjev-Kostic, Arpad Kiralj, Radmila Šećerov Sokolović


Bed coalescers are compact, easy to install, automate, and maintain with the ability to achieve high separation efficiencies. They have been increasingly applied in the industry even though their design often requires pilot plant experiments. In this paper, a new wetting property of polymer fibers regarding polar mineral oils was established. This property can be important for selection of filter media for liquid-liquid separation in many industrial applications. Medical oil was selected as the new reference liquid that does not wet the investigated polymers. The lipophilic/lyophobic ratio (LLR) reached values ranging from 3.28 to 18.81 and increased with the increase of the mineral oil polarity measured by the oil neutralization number. The LLR values were in an excellent agreement with the results obtained from the separation efficiency of a steady-state bed coalescer. Thus, simple, fast and inexpensive experiments can replace pilot plant or at least laboratory testing aiming at selecting a polymer for oil separation from wastewater.


oily water; fibre bed; coalescence efficiency; polymer fibre wettability; droplet separation


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