Reduction and prediction of N2O emission from an Anoxic/Oxic wastewater treatment plant upon DO control and model simulation

S. Sun (1) , Z. Bao , R. Li , D. Sun , H. Geng , X. Huang , J. Lin , P. Zhang (1) , R. Ma (1) , L. Fang (1) , X.-H. Zhang (2) , X. Zhao (1)

1 Shenzhen Univerisity [Shenzhen]
2 ISCR - Institut des Sciences Chimiques de Rennes

In order to make a better understanding of the characteristics of N2O emission in A/O wastewater treatment plant, full-scale and pilot-scale experiments were carried out and a back propagation artificial neural network model based on the experimental data was constructed to make a precise prediction of N2O emission. Results showed that, N2O flux from different units followed a descending order: aerated grit tank > oxic zone ≫ anoxic zone > final clarifier > primary clarifier, but 99.4% of the total emission of N2O (1.60% of N-load) was monitored from the oxic zone due to its big surface area. A proper DO control could reduce N2O emission down to 0.21% of N-load in A/O process, and a two-hidden-layers back propagation model with an optimized structure of 4:3:9:1 could achieve a good simulation of N2O emission, which provided a new method for the prediction of N2O emission during wastewater treatment. © 2017

Keywords: BP-ANN model; DO; N2O emission; Simulation; A/O process

Domains: Chemical Sciences

S. Sun, Z. Bao, R. Li, D. Sun, H. Geng, et al.. Reduction and prediction of N2O emission from an Anoxic/Oxic wastewater treatment plant upon DO control and model simulation. Bioresource Technology, 2017, 244, pp.800--809. ⟨10.1016/j.biortech.2017.08.054⟩. ⟨hal-01581229⟩