In this study, guidance is provided for applying microfiltration (MF) and ultrafiltration (UF) membranes to treat full-scale granular media filter (GMF) backwash water at drinking water plants. An example from the City of Melbourne in Florida is presented with the current approach to backwash water management at the full-scale along with a proposed approach to treat and directly blend MF/UF filtrate with treated water prior to final disinfection. Backwash water from the fullscale surface water treatment plant was characterized and bench-scale experiments were conducted to determine fouling propensity and operational parameters (flux, backwash frequency, chemical cleaning efficacy). The concentration of suspended solids, iron and manganese varied within a GMF backwash cycle and a methodology to handle high solids loading with low-pressure membrane filtration is presented. Treatment using low-pressure membranes will potentially enable direct blending of filtrate with finished potable water and reduce challenges associated with recycling backwash water, minimize solids loading on sludge handling facilities and reduce overall operational costs.
This presentation is available to AMTA Members only.
- Arun Subramani
- AMTA/AWWA Membrane Technology Conference, Las Vegas
- AMTA/AWWA Membrane Technology Conference
- Low-Pressure Membranes, Potable Reuse, Surface Water