title: Biodegradation of pharmaceuticals in hospital wastewater by staged Moving Bed Biofilm Reactors (MBBR).
abstract: Hospital wastewater represents a significant input of pharmaceuticals into municipal wastewater. As Moving Bed Biofilm Reactors (MBBRs) appear to remove organic micro-pollutants, hospital wastewater was treated with a pilot plant consisting of three MBBRs in series. The removal of pharmaceuticals was studied in two experiments: 1) A batch experiment where pharmaceuticals were spiked to each reactor and 2) a continuous flow experiment at native concentrations. DOC removal, nitrification as well as removal of pharmaceuticals (including X-ray contrast media, β-blockers, analgesics and antibiotics) occurred mainly in the first reactor. In the batch experiment most of the compounds followed a single first-order kinetics degradation function, giving degradation rate constants ranged from 5.77 × 10(-3) to 4.07 h(-1), from -5.53 × 10(-3) to 9.24 × 10(-1) h(-1) and from 1.83 × 10(-3) to 2.42 × 10(-1) h(-1) for first, second and third reactor respectively. Generally, the highest removal rate constants were found in the first reactor while the lowest were found in the third one. This order was inverted for most compounds, when the removal rate constants were normalized to biomass, indicating that the last tank had the most effective biofilms. In the batch experiment, 21 out of 26 compounds were assessed to be degraded with more than 20% within the MBBR train. In the continuous flow experiment the measured removal rates were lower than those estimated from the batch experiments.
authors.affiliation: Environmental Science, Aarhus University, Frederiksborgsvej 399, 4000 Roskilde, Denmark.
authors.forename: Mònica Escolà
authors.initials: ME
authors.lastname: Casas
authors.affiliation: Department of Environmental Engineering, Technical University of Denmark, Miljøvej 113, 2800 Kgs. Lyngby, Denmark.
authors.forename: Ravi Kumar
authors.initials: RK
authors.lastname: Chhetri
authors.affiliation: Environmental Science, Aarhus University, Frederiksborgsvej 399, 4000 Roskilde, Denmark.
authors.forename: Gordon
authors.initials: G
authors.lastname: Ooi
authors.affiliation: Department of Environmental Engineering, Technical University of Denmark, Miljøvej 113, 2800 Kgs. Lyngby, Denmark.
authors.forename: Kamilla M S
authors.initials: KM
authors.lastname: Hansen
authors.affiliation: Department of Chemistry and Biotechnology, Danish Technological Institute, Kongsvang Allé 29, DK-8000 Aarhus C, Denmark.
authors.forename: Klaus
authors.initials: K
authors.lastname: Litty
authors.affiliation: Veolia Water Technologies AnoxKaldnes, Klosterängsvägen 11A, SE-226 47 Lund, Sweden.
authors.forename: Magnus
authors.initials: M
authors.lastname: Christensson
authors.affiliation: Department of Chemistry and Biotechnology, Danish Technological Institute, Kongsvang Allé 29, DK-8000 Aarhus C, Denmark.
authors.forename: Caroline
authors.initials: C
authors.lastname: Kragelund
authors.affiliation: Department of Environmental Engineering, Technical University of Denmark, Miljøvej 113, 2800 Kgs. Lyngby, Denmark.
authors.forename: Henrik R
authors.initials: HR
authors.lastname: Andersen
authors.affiliation: Environmental Science, Aarhus University, Frederiksborgsvej 399, 4000 Roskilde, Denmark. Electronic address: kb@envs.au.dk.
authors.forename: Kai
authors.initials: K
authors.lastname: Bester
mesh_terms: D018407:Bacterial Physiological Phenomena; D001673:Biodegradation, Environmental; D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors; D003718:Denmark; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006761:Hospitals; D004364:Pharmaceutical Preparations / Q000378:metabolism*; D010865:Pilot Projects; D062065:Wastewater / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D004364:Pharmaceutical Preparations; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Biodegradation; Conjugates; Degradation kinetics; Hospital wastewater; Pharmaceuticals; X-ray contrast media