title: Photodegradation and sorption govern tetracycline removal during wastewater treatment in algal ponds.
abstract: The degradation of the antibiotic tetracycline, supplied at 100µgL-1in domestic wastewater, was studied in an outdoor, pilot scale, high rate algal pond (HRAP). Effective operation was demonstrated with the biomass concentration and the chemical oxygen demand removal efficiency averaging 1.2±0.1gTSSL-1and 80±4%, respectively, across all operational periods. Tetracycline removal exceeded 93% and 99% when the HRAP was operated at hydraulic retention times of 4 and 7days, respectively. Batch tests and pulse testing during HRAP operation repeatedly evidenced the significance of photodegradation as a removal mechanism. Sorption dominated tetracycline removal during the night, but accounted for less than 6% of the total pollutant removal based on sorbed tetracycline extracted from biomass. Overall, these results provide the first demonstration of efficient antibiotic removal, occurring mainly via indirect photodegradation, during relevant HRAP operation (low pollutant concentration, domestic wastewater and natural sunlight).
authors.affiliation: Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, Valladolid 47011, Spain; School of Engineering and Advanced Technology, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand.
authors.forename: Zane N
authors.initials: ZN
authors.lastname: Norvill
authors.affiliation: Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, Valladolid 47011, Spain.
authors.forename: Alma
authors.initials: A
authors.lastname: Toledo-Cervantes
authors.affiliation: The Institute of the Environment, La Serna, 58, 24007 Leon, Spain.
authors.forename: Saul
authors.initials: S
authors.lastname: Blanco
authors.affiliation: School of Engineering and Advanced Technology, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand.
authors.forename: Andy
authors.initials: A
authors.lastname: Shilton
authors.affiliation: School of Engineering and Advanced Technology, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand.
authors.forename: Benoit
authors.initials: B
authors.lastname: Guieysse
authors.affiliation: Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, Valladolid 47011, Spain. Electronic address: mutora@iq.uva.es.
authors.forename: Raul
authors.initials: R
authors.lastname: Muñoz
mesh_terms: D000327:Adsorption; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification; D061249:Batch Cell Culture Techniques; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D018533:Biomass; D006863:Hydrogen-Ion Concentration; D058086:Microalgae / Q000378:metabolism*; D010782:Photolysis; D010788:Photosynthesis; D010865:Pilot Projects; D061005:Ponds; D012722:Sewage / Q000382:microbiology; D013752:Tetracycline / Q000737:chemistry / Q000302:isolation & purification*; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D000900:Anti-Bacterial Agents; D012722:Sewage; D013752:Tetracycline; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Emerging pollutant; Microalgae; Photolysis; Raceway; Wastewater