PMID- 34955202
OWN - NLM
STAT- MEDLINE
DCOM- 20211228
LR  - 20221207
IS  - 1001-0742 (Print)
IS  - 1001-0742 (Linking)
VI  - 112
DP  - 2022 Feb
TI  - Enhancing anoxic denitrification of low C/N ratio wastewater with novel ZVI 
      composite carriers.
PG  - 180-191
LID - S1001-0742(21)00194-7 [pii]
LID - 10.1016/j.jes.2021.05.021 [doi]
AB  - External organic carbon sources are needed to provide electron donors for the 
      denitrification of wastewater with a low COD/NO(3)(-)-N (C/N) ratio, increasing 
      the treatment cost. The economic strategy is to enhance the bioactivity and/or 
      biodiversity of denitrifiers to efficiently utilize organic substances in 
      wastewater. In this study, novel zero-valent iron (ZVI) composite carriers were 
      prepared and implemented in a suspended carrier biofilm reactor to enhance the 
      bioactivity and/or biodiversity of denitrifiers. At the influent C/N ratio of 4 
      (COD was 179.5 +/- 5.0 mg/L and TN was 44.2 +/- 0.8 mg/L), COD and TN removal 
      efficiencies were 85.1% and 66.4%, respectively, in the reactors filled with 3 
      wt% ZVI composite carriers. In contrast, COD and TN removal efficiencies were 
      70.4% and 55.3%, respectively, in the reactor filled with conventional 
      high-density polyethylene (HDPE) biofilm carriers. The biofilm formation on the 
      3 wt% ZVI composite carriers was optimized due to its higher roughness (surface 
      square roughness increased from 76.0 nm to 93.8 nm) and favorable hydrophilicity 
      (water contact angle dropped to 72.5 degrees  +/- 1.4 degrees  from 94.3 degrees  +/- 3.2 degrees ) compared with the 
      HDPE biofilm carriers. In addition, heterotrophic denitrifiers, Thauera and 
      Dechloromonas, were enriched, whereas autotrophic denitrifiers, Raoultella and 
      Thiobacillus, exhibited high relative abundance in the biofilm of ZVI composite 
      carriers. The coexistence of heterotrophic denitrifiers and autotrophic 
      denitrifiers on the surface of ZVI composite carriers provided mixotrophic 
      metabolism of denitrification (including heterotrophic and iron-based 
      autotrophic), thereby ensuring effective denitrification for wastewater with a 
      low C/N ratio without external organic carbon source addition.
CI  - Copyright (c) 2021. Published by Elsevier B.V.
FAU - Shi, Yanping
AU  - Shi Y
AD  - Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of 
      Education), School of Environmental Science and Technology, Dalian University 
      ofTechnology, Dalian 116024, China.
FAU - Liu, Tao
AU  - Liu T
AD  - Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of 
      Education), School of Environmental Science and Technology, Dalian University 
      ofTechnology, Dalian 116024, China.
FAU - Yu, Hongtao
AU  - Yu H
AD  - Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of 
      Education), School of Environmental Science and Technology, Dalian University 
      ofTechnology, Dalian 116024, China.
FAU - Quan, Xie
AU  - Quan X
AD  - Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of 
      Education), School of Environmental Science and Technology, Dalian University 
      ofTechnology, Dalian 116024, China. Electronic address: quanxie@dlut.edu.cn.
LA  - eng
PT  - Journal Article
DEP - 20210605
PL  - Netherlands
TA  - J Environ Sci (China)
JT  - Journal of environmental sciences (China)
JID - 100967627
RN  - 0 (Waste Water)
RN  - E1UOL152H7 (Iron)
RN  - N762921K75 (Nitrogen)
SB  - IM
MH  - Autotrophic Processes
MH  - Bioreactors
MH  - *Denitrification
MH  - Iron
MH  - Nitrogen/analysis
MH  - *Wastewater
OTO - NOTNLM
OT  - Biofilm carrier
OT  - Denitrification
OT  - Integrated floating fixed-film and activated sludge (IFFAS)
OT  - Low C/N ratio
OT  - ZVI
EDAT- 2021/12/28 06:00
MHDA- 2021/12/29 06:00
CRDT- 2021/12/27 05:36
PHST- 2021/03/09 00:00 [received]
PHST- 2021/05/12 00:00 [revised]
PHST- 2021/05/13 00:00 [accepted]
PHST- 2021/12/27 05:36 [entrez]
PHST- 2021/12/28 06:00 [pubmed]
PHST- 2021/12/29 06:00 [medline]
AID - S1001-0742(21)00194-7 [pii]
AID - 10.1016/j.jes.2021.05.021 [doi]
PST - ppublish
SO  - J Environ Sci (China). 2022 Feb;112:180-191. doi: 10.1016/j.jes.2021.05.021. Epub 
      2021 Jun 5.