Cross-flow microfiltration with high frequency reverse flow

High frequency reverse filtration was evaluated while microfiltering a bent onite suspension, biologically treated wastewater and an activated sludge s uspension through a 0.2 mu m tubular ceramic membrane. Better results were obtained with a conventional internal layer filtration element than with an external skin membrane. However the technique was efficient in enhancing t he permeate flux solely with the bentonite suspension. In the other cases, the flux was the same as in conventional cross-flow operation. Such a failu re cannot be exclusively attributed to chemical interactions with the membr ane since the permeate flux increased linearly with cross-flow velocity for all suspensions in conventional operation. Much research is then required to establish the technique applicability.