The mechanism of extracellular polymeric substances in the formation of activated sludge flocs

被引:24
作者
An, Qiang [1 ]
Chen, Yuhang [1 ]
Tang, Meng [1 ]
Zhao, Bin [1 ]
Deng, Shuman [1 ]
Li, Zheng [1 ]
机构
[1] Chongqing Univ, Key Lab Three Gorges Reservoir Reg Eco Environm, Minist Educ, Chongqing 400045, Peoples R China
关键词
Extracellular polymeric substances; Activated sludge aggregation; Ion bridging; Hydrophobic interaction; Proteins secondary structure; GRANULAR SLUDGE; EPS; EXTRACTION; AGGREGATION;
D O I
10.1016/j.colsurfa.2023.131009
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
In this study, activated sludge (AS) presented high aggregation ability of 56.9% to form flocs. To elucidate the effects of extracellular polymeric substances (EPS) on the AS flocs formation, four EPS fractions, including soluble EPS (S-EPS), loosely bound EPS (LB-EPS), ionic tightly bound EPS (ionic TB-EPS) and hydrophobic tightly bound EPS (hy-drophobic TB-EPS), were extracted and characterized. The ionic TB-EPS were the largest fraction, accounting for 51.3% of the total EPS. By extracting EPS fractions, it was shown that ionic TB-EPS followed by hydrophobic TB-EPS played positive contribution to the formation of AS flocs, while both S-EPS and LB-EPS had negative effects. Furthermore, chemical reagents (Urea, SDS and EDTA) assays, zeta potential and spectroscopic assays were con-ducted to explore the role of hydrogen bonds, electrostatic interaction and hydrophobic interaction in the formation of AS flocs. The result showed that ionic TB-EPS contained sufficient cation-binding sites, such as-OH and C--O-O- groups, and promoted AS aggregation through ion bridging. Hydrophobic TB-EPS contained hydrophobic groups and promoted AS aggregation through hydrophobic action. A high proportion of uronic acids resulted in high surface negative charge, which might be the reason that LB-EPS and S-EPS inhibited AS aggregation through electrostatic repulsion. From the perspective of molecule structure, the proteins in ionic TB-EPS had a loose structure, which fully exposed the inner cation-binding sites. This might be the critical reason why ion bridging acted as the main force for the formation of AS flocs. This study provided a new sight for the extraction of EPS fractions and expanded the un-derstanding of EPS in the formation of AS flocs.
引用
收藏
页数:8
相关论文
共 45 条
  • [1] Single-culture aerobic granules with Acinetobacter calcoaceticus
    Adav, Sunil S.
    Lee, Duu-Jong
    [J]. APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 2008, 78 (03) : 551 - 557
  • [2] Role of extracellular polymeric substances in bioflocculation of activated sludge microorganisms under glucose-controlled conditions
    Badireddy, Appala R.
    Chellam, Shankararaman
    Gassman, Paul L.
    Engelhard, Mark H.
    Lea, Alan S.
    Rosso, Kevin M.
    [J]. WATER RESEARCH, 2010, 44 (15) : 4505 - 4516
  • [3] Parametric studies of formation and morphology of sub-micron sized GO stabilized PS/GO containers encapsulating 8-HQ
    Daradmare, Sneha
    Pradhan, Mamata
    Raja, V. S.
    Parida, Smrutiranjan
    [J]. POLYMER, 2017, 118 : 116 - 126
  • [4] Role of extracellular polymeric substances in biofilm formation by Pseudomonas stutzeri strain XL-2
    Ding, Xue Song
    Zhao, Bin
    An, Qiang
    Tian, Meng
    Guo, Jin Song
    [J]. APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 2019, 103 (21-22) : 9169 - 9180
  • [5] Characterization of the extracellular polymeric substances produced by Escherichia coli using infrared spectroscopic, proteomic, and aggregation studies
    Eboigbodin, Kevin E.
    Biggs, Catherine A.
    [J]. BIOMACROMOLECULES, 2008, 9 (02) : 686 - 695
  • [6] Composition analysis of fractions of extracellular polymeric substances from an activated sludge culture and identification of dominant forces affecting microbial aggregation
    Guo, Xuan
    Wang, Xu
    Liu, Junxin
    [J]. SCIENTIFIC REPORTS, 2016, 6
  • [7] Role of extracellular polymeric substance in determining the high aggregation ability of anammox sludge
    Hou, Xiaolin
    Liu, Sitong
    Zhang, Zuotao
    [J]. WATER RESEARCH, 2015, 75 : 51 - 62
  • [8] Stratification of Extracellular Polymeric Substances (EPS) for Aggregated Anammox Microorganisms
    Jia, Fangxu
    Yang, Qing
    Liu, Xiuhong
    Li, Xiyao
    Li, Baikun
    Zhang, Liang
    Peng, Yongzhen
    [J]. ENVIRONMENTAL SCIENCE & TECHNOLOGY, 2017, 51 (06) : 3260 - 3268
  • [9] Mechanical and chemical studies on EPS from Sulfobacillus thermosulfidooxidans: from planktonic to biofilm cells
    Li, Qian
    Sand, Wolfgang
    [J]. COLLOIDS AND SURFACES B-BIOINTERFACES, 2017, 153 : 34 - 40
  • [10] Influence of loosely bound extracellular polymeric substances (EPS) on the flocculation, sedimentation and dewaterability of activated sludge
    Li, X. Y.
    Yang, S. F.
    [J]. WATER RESEARCH, 2007, 41 (05) : 1022 - 1030