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[Influence of DO and aeration/non-aeration ratio on one-step SBBR completely autotrophic nitrogen removal process]
Fang Fang1, Guo-hong Yang, Jin-song Guo
1Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China. xiduo@tom.com
Abstract:
To improve the performance of single SBBR completely autotrophic nitrogen removal system and study the influence of aeration/non-aeration ratio on it, four reactors were applied in the experiment. The results showed that both continuous and intermittent aeration system could implement completely autotrophic nitrogen removal. On the conditions of ammonium concentration round 160 mg/L, temperature 30 degrees C +/- 2 degrees C, pH value 7.8-8.2, HRT 2 days and DO 0.8-1.0 mg/L, ammonium and total nitrogen removal efficiency reached 80% and 70% respectively in the continuous aeration system, and in the system of DO 2.0-2.5 (aeration) mg x L(-1)/ 0.2-0.4 (non-aeration) mg x L(-1), aeration/non-aeration ratio 2 h:2 h, ammonium and total nitrogen removal efficiency reached above 90% and 80% respectively. DO should be adjusted in accordance with aerobic/anaerobic ratio, and may be related to the biomass and its distribution between activated sludge and biofilm. The mechanism of nitrogen removal was also discussed.
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