title: Evaluation of a membrane bioreactor system as post-treatment in waste water treatment for better removal of micropollutants.
abstract: Organic micropollutants (OMPs) such as pharmaceuticals are persistent pollutants that are only partially degraded in waste water treatment plants (WWTPs). In this study, a membrane bioreactor (MBR) system was used as a polishing step on a full-scale WWTP, and its ability to remove micropollutants was examined together with the development and stability of the microbial community. Two stages of operation were studied during a period of 9 months, one with (S1) and one without (S2) the addition of exogenous OMPs. Ibuprofen and naproxen had the highest degradation rates with values of 248 μg/gVSS·h and 71 μg/gVSS·h, whereas diclofenac was a more persistent OMP (7.28 μg/gVSS·h). Mineralization of14C-labeled OMPs in batch kinetic experiments indicates that higher removal rates (∼0.8 ng/mgTSS·h) with a short lag phase can be obtained when artificial addition of organic micropollutants was performed. Similar microbial populations dominated S1 and S2, despite the independent operations. Hydrogenophaga, Nitrospira, p55-a5, the actinobacterial Tetrasphaera, Propionicimonas, Fodinicola, and Candidatus Microthrix were the most abundant groups in the polishing MBR. Finally, potential microbial candidates for ibuprofen and naproxen degradation are proposed.
authors: Instituto Potosino de Investigación Científica y Tecnológica, Environmental Sciences Department, Camino a la Presa San José 2055, Lomas 4a Sección, CP 78216, San Luis Potosí, Mexico; Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg East, Denmark.
authors: Sonia
authors: S
authors: Arriaga
authors: Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg East, Denmark.
authors: Nadieh
authors: N
authors: de Jonge
authors: Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg East, Denmark.
authors: Marc Lund
authors: ML
authors: Nielsen
authors: Department of Environmental Engineering, Technical University of Denmark, Miljøvej 113, 2800, Kgs. Lyngby, Denmark.
authors: Henrik Rasmus
authors: HR
authors: Andersen
authors: Krüger A/S, Gladsaxevej 363, 2860, Søborg, Denmark.
authors: Vibeke
authors: V
authors: Borregaard
authors: Bundesanstalt für Gewässerkunde, Am Mainzer Tor 1, 56068, Koblenz, Germany.
authors: Kevin
authors: K
authors: Jewel
authors: Bundesanstalt für Gewässerkunde, Am Mainzer Tor 1, 56068, Koblenz, Germany.
authors: Thomas A
authors: TA
authors: Ternes
authors: Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg East, Denmark. Electronic address: jln@bio.aau.dk.
authors: Jeppe Lund
authors: JL
authors: Nielsen
mesh_terms: D019149:Bioreactors; D014865:Waste Disposal, Fluid; D062065:Wastewater; D014867:Water; D014874:Water Pollutants, Chemical; D018508:Water Purification
chemical_list: D062065:Wastewater; D014867:Water; D014874:Water Pollutants, Chemical
keywords: Emerging organic; Membrane reactor; Micropollutants; Polishing step