A method to estimate the direct nitrous oxide emissions of municipal wastewater treatment plants based on the degree of nitrogen removal.

The greenhouse gas nitrous oxide (N2O) is produced in activated sludge tanks as a byproduct of nitrification and heterotrophic denitrification. Insufficient knowledge on how microbiological N2O generation and degradation pathways impact N2O emissions in activated sludge tanks still hampers the development of effective mitigation strategies. Our research contributes to overcome this gap by quantifying N2O emissions through extensive measurement campaigns at ten full-scale wastewater treatment plants and correlating them to relevant operating parameters by multivariate regression analysis. Measurements revealed that N2O production depends mainly on the activity of nitrifying bacteria and is triggered by high ammonium concentrations. In contrast, well-performing heterotrophic denitrification plays a key role as a sink of N2O in activated sludge tanks. Following these patterns, low loaded plants achieving high nitrogen removal (83-92%) exhibited the lowest N2O emission intensity (0.0012 ± 0.001 kg N2O-N emitted per kg TKN in the influent wastewater). The regression analysis corroborated these results by revealing a negative linear correlation between the N2O emission factor and the total nitrogen removal degree of the plants. The regression model represents a novel estimation method that links N2O emissions with plant performance and provides a significant improvement over approaches applying fixed N2O emission factors.

• Publication year

  2020

• Venue

  Journal of Environmental Management

• Publication date

  2020-11-11

• Fields of study

  Medicine, Environmental Science

• Identifiers
  DOI 10.1016/j.jenvman.2020.111563PMID 33189422
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

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  2014cited by this paper
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  2013cited by this paper
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  2013cited by this paper
• Nitrous oxide emissions and dissolved oxygen profiling in a full-scale nitrifying activated sludge treatment plant.

  2013influential reference
• Nitrous oxide formation during nitritation and nitrification of high-strength wastewater.

  2013cited by this paper
• Strategies to mitigate N2O emissions from biological nitrogen removal systems.

  2012cited by this paper
• N2O production rate of an enriched ammonia-oxidising bacteria culture exponentially correlates to its ammonia oxidation rate.

  2012cited by this paper
• Surveying N2O-producing pathways in bacteria.

  2011cited by this paper
• Nitrous oxide generation in full-scale biological nutrient removal wastewater treatment plants.

  2010cited by this paper
• N2O emissions from activated sludge processes, 2008-2009: results of a national monitoring survey in the United States.

  2010cited by this paper
• Nitrous oxide emission during wastewater treatment.

  2009cited by this paper
• Dynamics of nitric oxide and nitrous oxide emission during full-scale reject water treatment.

  2008cited by this paper
• Nitrous oxide emissions from secondary activated sludge in nitrifying conditions of urban wastewater treatment plants: effect of oxygenation level.

  2006influential reference
• The main wastewater treatment plant of Vienna: an example of cost effective wastewater treatment for large cities.

  2006cited by this paper
• Estimations of municipal point source pollution in the context of river basin management.

  2005cited by this paper
• Nitrous oxide production in high-loading biological nitrogen removal process under low COD/N ratio condition.

  2001cited by this paper
• Nitrous oxide emissions from municipal wastewater treatment.

  1995cited by this paper
• Release of nitric and nitrous oxides from denitrifying activated sludge

  1995cited by this paper
• Production of NO2- and N2O by Nitrifying Bacteria at Reduced Concentrations of Oxygen

  1980cited by this paper

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  2024cites this paper
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