Separation of oil drops from water using stainless steel fiber bed

Abstract

This study is focused on the separation of oil droplets from water by applying a stainless steel fiber bed. The separation efficiency was followed by monitoring the oil concentration of three mineral oils that have a wide range of viscosity from 10 to 170 mP s, as well as neutralization number from 0.10 to 1.70 mg KOH/l. The bed properties were varied by altering the bulk density of the filter material, which resulted in a change of bed permeability from 0.7?10-9 to 5.389?10-9 m2 and bed porosity from 91 to 98%. All experiments were conducted in a wide range of superficial velocity from 10 to 50 m/h. It can be concluded that high separation efficiency was achieved using stainless steel fibers, reaching values over 90%. Low bed permeability is most favorable for work at the selected conditions for the separation. The operation of stainless steel fiber bed is very sensitive to changes in the properties of oils. For lower viscosity of oily contaminants, the required efficiency of separation is achieved at lower superficial velocity through the fibrous bed. This phenomenon can be considered as a serious drawback since the bed coalescers often have to separate oils of different quality over time.