AWWA WQTC65926

The objective of this study was to assess the feasibility of using tubular, ceramic and hollow fiber microfiltration/ultrafiltration (MF/UF) membrane processes with larger pores at very high hydraulic loading rates (flux) for treatment of spent filter backwash (SFBW). It is expected that these processes will also provide excellent treated water quality with turbidity (solids level) likely to be lower than that resulting from processes such as conventional settling, high rate sedimentation or dissolved air flotation. The overall approach was to utilize both simulated and actual SFBW in bench-scale tests of membrane model performance. Descriptions of the SFBW, the bench-scale apparatus, the membrane modules and membrane operational procedures follow. It is very important to note that experiments were conducted with very small scale membrane modules in a constant TMP, varying flux approach, and at quite high absolute flux. These conditions would not likely be employed at pilot or full-scale with commercially available membrane elements; a constant flux, variable TMP approach with larger membrane modules would be used. Such testing needs to be conducted in another phase of work beyond this preliminary, investigation of concept, research phase. Includes 8 references, tables, figures.