Membrane Bioreactors in Waste Water Treatment – Status and Trends

Abstract

Due to their unique advantages like controlled biomass retention, improved effluent quality, and decreased footprint, membrane bioreactors (MBRs) are being increasingly used in waste water treatment up to a capacity of several 100,000 p.e. This article reviews the current status of MBRs and reports trends in MBR design and operation. Typical operational and design parameters are given as well as guidelines for waste water treatment plant revamping. To further improve the biological performance, specific or hybrid process configurations are shown to lead to, e.g., enhanced nutrient removal. With regards to reducing membrane fouling, optimized modules, advanced control, and strategies like the addition of flux enhancers are currently emerging. IntroductionThe first reported application of membrane bioreactor (MBR) technology in waste water treatment was in 1969, when an ultrafiltration membrane was used to separate activated sludge from the final effluent of a biological waste water treatment system, and the sludge was recycled back into the aeration tank [1]. Due to their unique advantages like superb and hygienic effluent and reduced footprint which has been shown on large scale [2], MBRs, which are combinations of common bioreactors and membrane filtration units for biomass retention, are becoming increasingly popular for waste water treatment. In Europe, the first full-scale MBR plant for treatment of municipal waste water was constructed in Porlock (UK, commissioned in 1998, 3800 p.e.), soon followed by the Büchel and Rödingen WWTPs (Germany, 1999, 1000 and 3000 p.e., respectively), and Perthes-en-Gâtinais WWTP (France, 1999, 4500 p.e.). . Since then, a large number of new results has been published presenting novel process configurations, more insight into the occurring phenomena, and pointing out innovative ways to combat fouling [11,12]. Between 2005 and 2009, the EC funded two major projects on all aspects of MBR technology (AMEDEUS and EUROMBRA), the outcomes of which can be found on www.mbr-network.eu. This paper aims to provide an overview of where MBR technology stands today and which future trends in process configuration and fouling control are emerging. Due to the vast amount of worldwide studies on MBR, this article will not be able to reflect all ongoing developments in the same depth, but will attempt to highlight the main economic and operational trends. Current Status of MBR Market and CapacityThe global market for membrane bioreactor technology is expected to grow at a compound annual growth rate of 10.5 %, increasing in value from $296.0 million in 2008 to $488.0 million by 2013. Growth rates of MBR systems are not the same for all world regions and are not increasing from the same base. Municipal/domestic wastewater treatment was the ear-

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Effect of Pac on MBR Performance During the Treatment of Synthetic Wastewater Containing Organic Compounds

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