title: Enhanced biodegradation of phenolic compounds in landfill leachate by enriched nitrifying membrane bioreactor sludge.
abstract: The role of autotrophic nitrification on the biodegradation of toxic organic micro-pollutants presented in landfill leachate was assessed. A two-stage MBR system consisting of an inclined tube incorporated anoxic reactor followed by aerobic submerged membrane reactor was operated under long sludge age condition in which nitrifying bacteria could be enriched. During the reactor operation, organic removal efficiencies were more than 90% whereas phenolic compounds including bisphenol A (BPA) and 4-methyl-2,6-di-tert-butylphenol (BHT) were removed by 65 and 70% mainly through biodegradation in the aerobic reactor even at high feed concentrations of 1000μg/L for both compounds. Batch experiments revealed that enriched nitrifying sludge with nitrifying activities could biodegraded 88 and 75% of BPA and BHT, largely improved from non-nitrifying sludge and enriched nitrifying sludge with the presence of inhibitor. The first-order kinetic rates of BHT and BPA removal were 0.0108 and 0.096h-1, also enhanced by 44% from the non-nitrifying sludge.
authors.affiliation: Department of Environmental Science and Natural Resources, Faculty of Science and Technology, Rajamangala University of Technology Phra Nakhon, Bangkok 10800, Thailand. Electronic address: varinthorn.b@rmutp.ac.th.
authors.forename: Varinthorn
authors.initials: V
authors.lastname: Boonyaroj
authors.affiliation: Department of Environmental Engineering & Center for Advanced Studies in Industrial Technology, Faculty of Engineering, Kasetsart University, Bangkok 10900, Thailand. Electronic address: fengccc@ku.ac.th.
authors.forename: Chart
authors.initials: C
authors.lastname: Chiemchaisri
authors.affiliation: Department of Environmental Engineering & Center for Advanced Studies in Industrial Technology, Faculty of Engineering, Kasetsart University, Bangkok 10900, Thailand. Electronic address: fengwlc@ku.ac.th.
authors.forename: Wilai
authors.initials: W
authors.lastname: Chiemchaisri
authors.affiliation: Environmental Science Center, University of Tokyo, Tokyo 113, Japan. Electronic address: yamamoto@esc.u-tokyo.ac.jp.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yamamoto
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D004785:Environmental Pollutants / Q000032:analysis; D007700:Kinetics; D058465:Nitrification; D009576:Nitrobacter / Q000378:metabolism; D009584:Nitrogen; D010636:Phenols / Q000032:analysis*; D020560:Proteobacteria / Q000378:metabolism; D012722:Sewage / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D004785:Environmental Pollutants; D010636:Phenols; D012722:Sewage; D014874:Water Pollutants, Chemical; D009584:Nitrogen
keywords: Emerging contaminant; Enriched nitrifying sludge; Landfill leachate; Membrane bioreactor; Phenolic compounds