TY - JOUR
T1 - Membrane fouling potentials and cellular properties of bacteria isolated from fouled membranes in a MBR treating municipal wastewater
AU - Ishizaki, So
AU - Fukushima, Toshikazu
AU - Ishii, Satoshi
AU - Okabe, Satoshi
N1 - Publisher Copyright:
© 2016 Elsevier Ltd
PY - 2016/9/1
Y1 - 2016/9/1
N2 - Membrane fouling remains a major challenge for wider application of membrane bioreactors (MBRs) to wastewater treatment. Membrane fouling is mainly caused by microorganisms and their excreted microbial products. For development of more effective control strategies, it is important to identify and characterize the microorganisms that are responsible for membrane fouling. In this study, 41 bacterial strains were isolated from fouled microfiltration membranes in a pilot-scale MBR treating real municipal wastewater, and their membrane fouling potentials were directly measured using bench-scale cross-flow membrane filtration systems (CFMFSs) and related to their cellular properties. It was found that the fouling potential was highly strain dependent, suggesting that bacterial identification at the strain level is essential to identify key fouling-causing bacteria (FCB). The FCB showed some common cellular properties. The most prominent feature of FCB was that they formed convex colonies having swollen podgy shape and smooth lustrous surfaces with high water, hydrophilic organic matter and carbohydrate content. However, general and rigid biofilm formation potential as determined by microtiter plates and cell surface properties (i.e., hydrophobicity and surface charge) did not correlate with the fouling potential in this study. These results suggest that the fouling potential should be directly evaluated under filtration conditions, and the colony water content could be a useful indicator to identify the FCB.
AB - Membrane fouling remains a major challenge for wider application of membrane bioreactors (MBRs) to wastewater treatment. Membrane fouling is mainly caused by microorganisms and their excreted microbial products. For development of more effective control strategies, it is important to identify and characterize the microorganisms that are responsible for membrane fouling. In this study, 41 bacterial strains were isolated from fouled microfiltration membranes in a pilot-scale MBR treating real municipal wastewater, and their membrane fouling potentials were directly measured using bench-scale cross-flow membrane filtration systems (CFMFSs) and related to their cellular properties. It was found that the fouling potential was highly strain dependent, suggesting that bacterial identification at the strain level is essential to identify key fouling-causing bacteria (FCB). The FCB showed some common cellular properties. The most prominent feature of FCB was that they formed convex colonies having swollen podgy shape and smooth lustrous surfaces with high water, hydrophilic organic matter and carbohydrate content. However, general and rigid biofilm formation potential as determined by microtiter plates and cell surface properties (i.e., hydrophobicity and surface charge) did not correlate with the fouling potential in this study. These results suggest that the fouling potential should be directly evaluated under filtration conditions, and the colony water content could be a useful indicator to identify the FCB.
KW - Colony water content
KW - Cross-flow filtration system
KW - Fouling-causing bacteria (FCB)
KW - Hydrophilic organic matter
KW - Membrane fouling potential
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U2 - 10.1016/j.watres.2016.05.027
DO - 10.1016/j.watres.2016.05.027
M3 - Article
C2 - 27232989
AN - SCOPUS:84989907452
SN - 0043-1354
VL - 100
SP - 448
EP - 457
JO - Water Research
JF - Water Research
ER -