Reference

Brepols, C. (2011) Operating large scale membrane bioreactors for municipal wastewater treatment, ISBN: 1843393050, IWA publishing, London, UK,  p.48 Crawford, G.; Lewis, R. (2004) Traverse City: the largest operating MBR facility in north America, Proceeding of WEFTEC, New Orleans, Louisiana, USA. Crawford, G.; Daigger, G.; Erdal, Z. (2006) Enhanced biological phosphorus removal within membrane bioreactors, […]

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Nordkanal WWTP, Kaarst, Germany (Engelhardt, 2008; Brepols, 2011)

The Nordkanal wastewater treatment plant, owned and operated by Erftverband, a German public utility institution for water management, discharges effluent to nearby canal and needed to improve effluent quality to meet the new effluent standard. At the same time, treatment capacity increase was required to relieve the chronic hydraulic overloading. The old WWTP was dismantled […]

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Traverse City, Michigan, USA (Crawford, 2004, 2006; Daigger, 2010)

The existing VIP process, which is virtually identical to UCT process except its shorter SRT, required a capacity increase by 40% without increasing footprint. In addition, no increase of pollutant discharge to the nearby lake was desired while treating more wastewater. MBR was chosen for the upgrade project and was commissioned in the summer of […]

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Fundamental Issues of BNR process design in MBR

The implementation of biological nutrient removal (BNR) processes in MBR relies on the same principle used in conventional activated sludge (CAS). But, there are some unique factors that must be taken into consideration (Crawford, 2006; Daigger, 2010). Excess DO returns to anoxic tank – The mixed liquor in membrane tank typically contains dissolved oxygen (DO) […]

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Potential toxicity of metal ions to nitrifiers

Gaps between short-term tests and long-term tests High level iron and aluminum ions have been suspected toxic to nitrifiers in biological wastewater treatment although there are no definitive evidences. Following are the claims found in literature, which are based on lab experiments. The ferrous ion (Fe2+) concentration higher than 20 mg/L appeared toxic to Nitrosomonas […]

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