Critical flux enhancement in electrically assisted microfiltration

The use of electric fields as a means to enhance the critical flux of non-circular ceramic membranes is considered. The electrofiltration performance is appraised with reference to (i) fouling propensity, i.e. critical flux and (ii) removal of organics. Critical flux determinations were carried out using constant transmembrane pressure step increments. The effluent from a synthetic activated sludge production process was used. Increasing the applied voltages appears to increase the critical flux. When the applied polarity of voltage is changed, the opposite trend is observed. Total organic content (TOC) removals of up to 90% are achieved which increase with increasing voltages. Good critical fluxes and permeate quality could be achieved with the electrical aid however; this is also accompanied with a substantial increase in energy consumption.

Research highlights
► Increasing the field strength led to an increase of up to 3 times more through-put in terms of flux and significant improvement in the TOC removals (up to 90%).
► Total specific energy consumption observed for the star shaped channeled membranes is much smaller compared to those observed in literature.
► Energy consumed by electric field constitutes the majority of the total energy consumed (>87%).