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as piezoelectric drivers. Even when high voltage pulses were applied to polymorph PVDF n'_mbranes, no significant permeate flux enhancement was recorded. Detailed feasibility studies were conducted to measure the long-term effect of a piezoelecmc horn on+ ulu'afiltration. Flux was enhanced by a factor of 4 for the filtration of a 1.0% polyethylene glycol solution through a regenerated cellulose tTF rnembr',mewhen a nominal power of' 10 watts was applied to the piezoelectric horr, in contact with a 47-mm membrane. This specific experiment was run over 2I days, after having reached constant fouling of the membranj. Evenhigher permeate flux enhancements wereobtained with piezoelectric PZT disc drivers. Permeate flow rate wasincreased by afactor of8 during theRltmtion ofa0.45%dextran solution through aUF polysulfone membrane(47mm diameter) assisted t:" a2.5-mm-thick lead 'zirconate titanate piezoelectric disc driven at40watts (2.3 W/cre2). We ha notyet attempted to optimize thepowerconsumption andperformance ofLhcpiezoelectric. PZT disc driver. PZT disc expcrirncnts havebeenrepeated many times over aperiod ofonemonthwith consistent enhancement oftheflux. No cross flow velocity experiments havebeencarried outindetail. However, thefeed flowr'atc wasmaintained between 1.4 and1.6 IJmin. Ourexperiments showthat thePZT disc produces higher flux enhancements (uptoafactor of8)than thepiezoelectric bom (uptoa factor of4),Wc believe that thePZT disc isa more, efficient driver since it is free floating onthepermeate side offibre ultrafiltration membrane, while the piezoelectric horn that isadapted toconstitute thetopportion ofthetest cell isimmobilized and therefore doesnotefficiently wansrnit energy tothemembrane Because ofthehigh efficiency andease ofadaptability ofceramic elerncnt drivers, wc plan adetailed study oftheir long-term performance on piezoelectric-driven ulu-af'fltration inYear2. This study will provide abasis forapplying piezoclectricaUy assisted ULtrafflu'ation tc) industrial processes suchaswheyprotein filtration andsolvent recovery inde, asi>halting. We will also pursue thedcvcloprncnt ofceramic piezoelectric drivers with controllc_:l porosity toovercome the major limitation ofthePZT disc drivers andstill provide abacking support totheultrafiltration membrane._Furthcr, we will configure oneormorebacking supports prototypical ofthe supports necessary forwinding into spiral modules.