title: Emission of nitrous oxide and nitric oxide from a full-scale single-stage nitritation-anammox reactor.
abstract: At a full-scale single-stage nitritation-anammox reactor, off-gas measurement for nitric oxide (NO) and nitrous oxide (N(2)O) was performed. NO and N(2)O are environmental hazards, imposing the risk of improving water quality at the cost of deteriorating air quality. The emission of NO during normal operation of a single-stage nitritation-anammox process was 0.005% of the nitrogen load while the N(2)O emission was 1.2% of the nitrogen load to the reactor, which is in the same range as reported emission from other full-scale wastewater treatment plants. The emission of both compounds was strongly coupled. The concentration of NO and N(2)O in the off-gas of the single-stage nitritation-anammox reactor was rather dynamic and clearly responded to operational variations. This exemplifies the need for time-dependent measurement of NO and N(2)O emission from bioreactors for reliable emission estimates. Nitrite accumulation clearly resulted in increased NO and N(2)O concentrations in the off-gas, yielding higher emission levels. Oxygen limitation resulted in a decrease in NO and N(2)O emission, which was unexpected as oxygen limitation is generally assumed to cause increased emissions in nitrogen converting systems. Higher aeration flow dramatically increased the NO emission load and also seemed to increase the N(2)O emission, which stresses the importance of efficient aeration control to limit NO and N(2)O emissions.
authors: Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC, Delft, The Netherlands.
authors: M J
authors: MJ
authors: Kampschreur
authors: R
authors: R
authors: Poldermans
authors: R
authors: R
authors: Kleerebezem
authors: W R L
authors: WR
authors: van der Star
authors: R
authors: R
authors: Haarhuis
authors: W R
authors: WR
authors: Abma
authors: M S M
authors: MS
authors: Jetten
authors: M S M
authors: MS
authors: Jetten
authors: M C M
authors: MC
authors: van Loosdrecht
mesh_terms: D000332:Aerobiosis; D000393:Air Pollutants / Q000032:analysis*; D017752:Greenhouse Effect; D009569:Nitric Oxide / Q000032:analysis*; D009609:Nitrous Oxide / Q000032:analysis*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000032:analysis / Q000737:chemistry*; D012995:Solubility; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*; D018508:Water Purification / Q000295:instrumentation* / Q000379:methods / Q000592:standards
chemical_list: D000393:Air Pollutants; D000644:Quaternary Ammonium Compounds; D014874:Water Pollutants, Chemical; D009569:Nitric Oxide; D009609:Nitrous Oxide; D010100:Oxygen