FLUX ENHANCEMENT IN LAMINAR CROSS-FLOW MICROFILTRATION USING A COLLAPSIBLE-TUBE PULSATION GENERATOR

A 0.5 g/l suspension of silica particles (range 0.2-8.0 mu m) in water was microfiltered in a Millipore 0.2 mu m unbaffled tubular ceramic m embrane. The crossflow was varied periodically at frequencies inducing fluid-dynamic unsteadiness using a collapsible-tube pulsation generat or. The time-averaged Reynolds number at the membrane inlet was 1340. The time-averaged transmembrane pressure, (P) over bar(tm), was system atically varied from 70 to 180 kPa With pulsation the filtrate flux re ached a plateau faster than in steady how at the same (P) over bar(tm) , and time-averaged crossflow velocity. The flux enhancement (pulsatin g-flow flux/steady-flow flux) increased with increasing (P) over bar(t m), reaching 450%. (C) 1998 Elsevier Science B.V.