TY - JOUR
T1 - Weak electricity stimulates biological nitrate removal of wastewater
T2 - Hypothesis and first evidences
AU - Liu, Hongbo
AU - Ouyang, Feiyu
AU - Chen, Zihua
AU - Chen, Zhongbing
AU - Lichtfouse, Eric
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/2/25
Y1 - 2021/2/25
N2 - Nitrate pollution in water is a worldwide health and environmental concern. Biological nitrate removal of wastewater is widely used countering eutrophication of water bodies; however it could be troublesome and expensive when influent carbon source is insufficient. Here we present a novel process, the microbial fuel cell (MFC)-resistance-type electrical stimulation denitrification process (RtESD) using microbial weak electricity originated from the wastewater, to enhance nitrate removal. Results show that the optimal nitrate dependent denitrification rate (0.027 mg N/L·h) and nitrate removal efficiency (98.1%) can be achieved; partial autotrophic denitrification was enhanced in RtESD under stimulation of 0.2 V of microbial weak electricity (MWE). Aromatic proteins also increased in the presence of 0.2 V MWE stimulation according to three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy profiles, indicating that electron transfer could be improved in the case of MWE stimulation. Furthermore, the microbial community structure and diversity analysis results demonstrated that MWE stimulation inhibited the heterotrophic denitrifying bacteria and activated the autotrophic denitrifying bacteria in RtESD. Two hypotheses, enhancement of electron transfer and improvement of microorganism activity, were proposed regarding to the MWE stimulated pathways. This study provided a promising method utilizing MWE derived from wastewater to improve the denitrification rate and removal efficiency of nitrate-containing wastewater treatment processes.
AB - Nitrate pollution in water is a worldwide health and environmental concern. Biological nitrate removal of wastewater is widely used countering eutrophication of water bodies; however it could be troublesome and expensive when influent carbon source is insufficient. Here we present a novel process, the microbial fuel cell (MFC)-resistance-type electrical stimulation denitrification process (RtESD) using microbial weak electricity originated from the wastewater, to enhance nitrate removal. Results show that the optimal nitrate dependent denitrification rate (0.027 mg N/L·h) and nitrate removal efficiency (98.1%) can be achieved; partial autotrophic denitrification was enhanced in RtESD under stimulation of 0.2 V of microbial weak electricity (MWE). Aromatic proteins also increased in the presence of 0.2 V MWE stimulation according to three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy profiles, indicating that electron transfer could be improved in the case of MWE stimulation. Furthermore, the microbial community structure and diversity analysis results demonstrated that MWE stimulation inhibited the heterotrophic denitrifying bacteria and activated the autotrophic denitrifying bacteria in RtESD. Two hypotheses, enhancement of electron transfer and improvement of microorganism activity, were proposed regarding to the MWE stimulated pathways. This study provided a promising method utilizing MWE derived from wastewater to improve the denitrification rate and removal efficiency of nitrate-containing wastewater treatment processes.
KW - Microbial fuel cell (MFC)
KW - Microbial weak electricity (MWE)
KW - Nitrate (NO-N) containing wastewater
KW - Resistance-type electrical stimulation denitrification (RtESD)
UR - https://www.scopus.com/pages/publications/85096838957
U2 - 10.1016/j.scitotenv.2020.143764
DO - 10.1016/j.scitotenv.2020.143764
M3 - 文章
C2 - 33248788
AN - SCOPUS:85096838957
SN - 0048-9697
VL - 757
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 143764
ER -