TY - JOUR
T1 - Fate of NaClO and membrane foulants during in-situ cleaning of membrane bioreactors
T2 - Combined effect on thermodynamic properties of sludge
AU - Zhang, Haifeng
AU - Sun, Ming
AU - Song, Lianfa
AU - Guo, Jingbo
AU - Zhang, Lanhe
N1 - Funding Information:
The authors wish to thank and acknowledge the support of the National Natural Science Foundation of China (No. 51478093 & 51678119 ), the Jilin Province Scientific and the Technological Planning Project of China (No. 20170519013JH ).
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/7/15
Y1 - 2019/7/15
N2 - In this study, the fate of sodium hypochlorite (NaClO) and detached membrane foulants and their impacts on the thermodynamic properties of raw sludge were investigated in a membrane bioreactor (MBR). It was found that about 20.3% of the total NaClO was potentially released into the bulk sludge, which significantly altered the raw sludge surface properties, such as a reduction in the number of surface electron donor components (γ−) and an increase in surface hydrophobicity. After exposure to NaClO, the treated sludge had a higher adhesive and cohesive propensity compared to the raw sludge. Based on the extended Derjaguin-Landau-Verwey- Overbeek (XDLVO) theory and the batch filtration test results, the detached foulants potentially aggregated with the treated sludge and form the reconstructed sludge. The reconstructed sludge had a high protein (PN) level in the extracellular polymeric substances (EPS), with a higher membrane fouling potential compared with the raw sludge.
AB - In this study, the fate of sodium hypochlorite (NaClO) and detached membrane foulants and their impacts on the thermodynamic properties of raw sludge were investigated in a membrane bioreactor (MBR). It was found that about 20.3% of the total NaClO was potentially released into the bulk sludge, which significantly altered the raw sludge surface properties, such as a reduction in the number of surface electron donor components (γ−) and an increase in surface hydrophobicity. After exposure to NaClO, the treated sludge had a higher adhesive and cohesive propensity compared to the raw sludge. Based on the extended Derjaguin-Landau-Verwey- Overbeek (XDLVO) theory and the batch filtration test results, the detached foulants potentially aggregated with the treated sludge and form the reconstructed sludge. The reconstructed sludge had a high protein (PN) level in the extracellular polymeric substances (EPS), with a higher membrane fouling potential compared with the raw sludge.
KW - Extracellular polymeric substances
KW - In-situ cleaning
KW - Interactions energy
KW - Membrane bioreactor
KW - Membrane foulants
UR - http://www.scopus.com/inward/record.url?scp=85064566347&partnerID=8YFLogxK
U2 - 10.1016/j.bej.2019.04.016
DO - 10.1016/j.bej.2019.04.016
M3 - Article
AN - SCOPUS:85064566347
SN - 1369-703X
VL - 147
SP - 146
EP - 152
JO - Biochemical Engineering Journal
JF - Biochemical Engineering Journal
ER -