title: Seasonal and diurnal variability of N2O emissions from a full-scale municipal wastewater treatment plant.
abstract: During nitrogen removal in conventional activated sludge processes, nitrous oxide can be emitted. With a global warming potential of 298 CO2-equivalents it is an important greenhouse gas that affects the sustainability of wastewater treatment. The present study reports nitrous oxide emission data from a 16 month monitoring campaign on a full-scale municipal wastewater treatment. The emission demonstrated a pronounced diurnal and seasonal variability. This variability was compared with the variability of a number of process variables that are commonly available on a municipal wastewater treatment plant. On a seasonal timescale, the occurrence of peaks in the nitrite concentration correlated strongly with the emission. The diurnal trend of the emission coincided with the diurnal trend of the nitrite and nitrate concentrations in the tank, suggesting that suboptimal oxygen concentrations may induce the production of nitrous oxide during both nitrification and denitrification. This study documents an unprecedented dataset that could serve as a reference for further research.
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands; Department of Biosystems engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium. Electronic address: m.r.j.daelman@tudelft.nl.
authors.forename: Matthijs R J
authors.initials: MRJ
authors.lastname: Daelman
authors.affiliation: Royal HaskoningDHV, P.O. Box 151, 6500AD Nijmegen, The Netherlands.
authors.forename: Ellen M
authors.initials: EM
authors.lastname: van Voorthuizen
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors.forename: Udo G J M
authors.initials: UGJM
authors.lastname: van Dongen
authors.affiliation: Department of Biosystems engineering, Ghent University, Coupure links 653, 9000 Gent, Belgium.
authors.forename: Eveline I P
authors.initials: EIP
authors.lastname: Volcke
authors.affiliation: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors.forename: Mark C M
authors.initials: MCM
authors.lastname: van Loosdrecht
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000706:statistics & numerical data*; D058440:Denitrification; D004784:Environmental Monitoring; D009609:Nitrous Oxide / Q000032:analysis*; D012621:Seasons; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D009609:Nitrous Oxide; D062065:Wastewater
keywords: Activated sludge process; Biological nitrogen removal; Climate footprint; Greenhouse gases; Nitrous oxide; Wastewater treatment