Bioaugmentation of nitrate-dependent anaerobic ferrous oxidation by heterotrophic denitrifying sludge addition: A promising way for promotion of chemoautotrophic denitrification.
Nitrate-dependent anaerobic ferrous oxidation (NAFO) is a new and valuable bio-process for the treatment of wastewaters with low C/N ratio, and the NAFO process is in state of the art. The heterotrophic denitrifying sludge (HDS), possessing NAFO activity, was used as bioaugmentation to enhance NAFO efficiency. At a dosage of 6% (V/V), the removal of nitrate and ferrous was 2.4 times and 2.3 times of as primary, and the volumetric removal rate (VRR) of nitrate and ferrous was 2.4 times and 2.2 times of as primary. Tracing experiments of HDS indicated that the bioaugmentation on NAFO reactor was resulted from the NAFO activity by HDS itself. The predominant bacteria in HDS were identified as Thauera (52.5%) and Hyphomicrobium (20.0%) which were typical denitrifying bacteria and had potential ability to oxidize ferrous. In conclusion, HDS could serve as bioaugmentation or a new seeding sludge for operating high-efficiency NAFO reactors.
Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
Ru
R
Wang
Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China. Electronic address: pzheng@zju.edu.cn.
Ping
P
Zheng
Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
Meng
M
Zhang
Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
He-Ping
HP
Zhao
College of Environmental Science and Engineering, Ocean University of China, Qingdao 266003, PR China.
Jun-Yuan
JY
Ji
Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
Xiao-Xin
XX
Zhou
Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.
Wei
W
Li
D058440:Denitrification; D052836:Heterotrophic Processes; D020582:Hyphomicrobium / Q000378:metabolism; D007501:Iron / Q000378:metabolism; D059013:Microbial Consortia / Q000502:physiology*; D009566:Nitrates / Q000378:metabolism*; D010084:Oxidation-Reduction; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000379:methods*
D009566:Nitrates; D012722:Sewage; D007501:Iron
Bioaugmentation; Ferrous oxidation; Heterotrophic denitrifying sludge; Nitrate reduction