ZHANG Weitang, XUE Xiaofei, PANG Hongtao, et al. Effect of C/N on performance of AAO-BAF process[J]. CIESC Journal, 2015, (5): 1925-1930.DOI: 10.11949/j.issn.0438-1157.20141719.
Combining anaerobic-anoxic-oxic reactor with an external nitrification biological aerated filter
the AAO-BAF process was used to treat domestic wastewater. Adjusting the influent COD concentration from 211 to 675 mg·L-1
the effect of carbon-nitrogen ratio (C/N) on the performance of the AAO-BAF process was investigated. A low or high influent organic concentration had significant effect on the nutrients removal efficiency due to the deficient phosphorus release or nitrate competition in the anoxic zones of the AAO reactor between DPAOs and ordinary heterotrophic organisms. When C/N was between 4 and 7
the average removal efficiencies of COD
TN and PO43- could reach more than 86%
78% and 90% respectively. Large quantity of residual volatile fatty acid (VFA)would be transferred into the anoxic zones when C/N was very high (such as 9.5)
which would cause rapid consumption of NO3- by ordinary heterotrophic organisms rather than denitrifying phosphorus accumulating organisms (DPAOs).