Poor performance from membrane filtration plants causes higher operating costs and can limit production. Performance issues generally can be classified as either fouling or fiber breaks. Fouling is a pervasive issue in membrane filtration impacting all facilities at some level. Fouling left unchecked compounds into irreversible damage to the membrane which cannot be removed by cleaning processes. In some cases, membrane fouling leads to premature replacement of the membranes and generally costs utilities thousands to millions of dollars. Fouling is a site-specific complex phenomenon which results from multiple causes and varies both temporally (e.g. seasonally) and spatially (e.g. by water source). Foulants which attach to the surface of the membrane are typically complexes of multiple contaminants such as organics and metals. Prediction of these foulants is not feasible during design or piloting and therefore most plants are set up on one standard cleaning recipe upon startup. This recipe consists generally of a chlorine followed by acid (citric acid and a mineral acid) clean-in-place (or recovery clean) conducted at a 30-day interval with a daily or weekly maintenance clean (or chemically enhanced backwash) with chlorine and/or citric acid. Generally, water and reuse membrane filtration plants will not vary these cleans during their history and many cannot address long term fouling. This paper explores a framework for managing fouling explored through discussions of three case studies.
This presentation is available to AMTA Members only.
- Karla Kinser
- Burns & McDonnell
- AMTA/AWWA Membrane Technology Conference, Las Vegas
- AMTA/AWWA Membrane Technology Conference
- Fouling, Fiber Breaks, Membrane Cleaning