Details

Autor(en) / Beteiligte

• Chai, Hongxiang
• Xiang, Yu
• Chen, Rong
• Shao, Zhiyu
• Gu, Li
• Li, Li
• He, Qiang

Titel

Enhanced simultaneous nitrification and denitrification in treating low carbon-to-nitrogen ratio wastewater: Treatment performance and nitrogen removal pathway

Ist Teil von

• Bioresource technology, 2019-05, Vol.280, p.51-58

Ort / Verlag

England: Elsevier Ltd

Erscheinungsjahr

2019

Quelle

Access via ScienceDirect (Elsevier)

Beschreibungen/Notizen

• [Display omitted] •The system reached a simultaneous nitrification and denitrification rate of 99.9%•ATU and ClO3− did not inhibit unconventional nitrogen removal pathways.•Unconventional pathways counted for 51% emitted N2O and 55% removed ammonia.•Heterotrophic nitrifiers stimulated nitrification in the system.•Denitrifiers with periplasmic nitrate reductase were enhanced for denitrification. Simultaneous nitrification and denitrification (SND) is an energy-saving wastewater treatment process, however, the nitrogen removal pathways are not clear. An enhanced SND sequencing batch biofilm reactor with a SND ratio above 97.3% was built to treat low carbon to nitrogen ratio wastewater. When traditional nitrification was inhibited, ammonia removal efficiency still reached 45% in 8 h while the NO3− and NO2− concentration was less than 3 mg/L and 0.01 mg/L during the complete process, respectively. The pathways that could not be suppressed by the inhibitors (ATU and ClO3−) were stimulated by heterotrophic nitrifiers and aerobic denitrifiers with periplasmic nitrate reductase and contributed 55% of the total removed NH4+ and produced 51% of the emitted N2O. The contributions of different nitrogen removal pathways indicate that the unconventional pathways are important in wastewater treatment system and inhibitors should be carefully used in nitrogen removal pathway assays.