Nitrous oxide emissions from the aeration tank of a wastewater treatment plant with conventional activated sludge process

摘要

Nitrous oxide (N_2O) emissions were measured monthly from January to June 2010 in the aeration tank of a wastewater treatment plant (WWTP) in Southeast Brazil. Emissions were lower in summer than winter and were positively related with influent ammonium (NH4 ~+) concentration. The average N_2O emission was 1.11 kg N day~(-1) corresponding to 0.02% of the influent total nitrogen load. The average emission factor calculated for the population served was 2.5 lower than that proposed by the Intergovernmental Panel on Climate Change (IPCC) for inventories of N _2O emissions from WWTPs with controlled nitrification and denitrification processes.