AWWA MTC53881

The feasibility of ultra and microfiltration depends strongly on the achieved net flux.Direct treatment of surface water frequently results in low net fluxes and high cleaningfrequencies. This is largely determined by the quality of the feed water and themechanisms that determine the fouling and the fouling rate of the membranes.Controlling and preferably reducing the rate of fouling is a major challenge. Researchhas been carried out to reduce fouling to achieve a stable operation at an economicalfeasible net flux. This research investigates decreasing the membrane contact area forsuspended and colloidal matter by a dynamic filter, i.e. Enhanced Pre-Coat Engineering(EPCE). The general applicability and the effects on the membrane performance of thisnew approach, have been determined using different water sources and with different pre-coat materials. Pre-coating results initially in a higher fouling rate, however this foulingrate stabilizes after several filtration cycles. The stabilization is caused by a betterrestoration of the permeability after a backwash and an enhanced backwash. From thisresearch it can be concluded that EPCE is a promising technique to increase membraneperformance. Long term effects, costs and full-scale implementation need to bedemonstrated. Includes 8 references, tables, figures.