Shear enhanced microfiltration and rejection of crude oil drops through a slotted pore membrane including migration velocities

Shear enhanced microfiltration of crude oil/water emulsion is investigated and the effect of an applied shear rate on the rejection of drops by the membrane is reported. Applying vibration provides shear at the membrane surface leading to shear-induced migration and an inertial lift of drops/particles. Both phenomena tend to move the drops away from the membrane surface. The shear-induced migration and inertial lift migration increase with increasing shear rates. A mathematical model is presented to account for the presence of both phenomena. The developed model is used for theoretical prediction of 100% cut-off of crude oil drops by the membrane with, and with-out, vibration applied. A satisfactory agreement of the model predictions with experimental data shows that the model can be successfully used for a theoretical prediction of 100% cut-off of drops by slotted pore membranes. When applying a shear rate of 8000 s(-1) and 2001 m(-2) h(-1) flux rate, 3-4 mu m radius drops were almost completely rejected; reducing 400 ppm of crude in the feed to 7 ppm in the permeate. (C) 2012 Elsevier B.V. All rights reserved.