Fouling potential of lipopolysaccharides released at low temperatures in MBRs

Sludge filterability in membrane bioreactors (MBRs) fluctuates and affects membrane fouling. Therefore, understanding the reasons for the fluctuations of sludge filterability is important for the efficient operation of MBRs. In this study, a pilot-scale MBR treating municipal wastewater was operated...

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Bibliographische Detailangaben
Veröffentlicht in:Water science and technology : a journal of the International Association on Water Pollution Research. - 1986. - 81(2020), 3 vom: 08. Feb., Seite 529-534
1. Verfasser: Kakuda, T (VerfasserIn)
Weitere Verfasser: Iwasaki, H, Kimura, K
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2020
Zugriff auf das übergeordnete Werk:Water science and technology : a journal of the International Association on Water Pollution Research
Schlagworte:Journal Article Lipopolysaccharides Membranes, Artificial Sewage
Beschreibung
Zusammenfassung:Sludge filterability in membrane bioreactors (MBRs) fluctuates and affects membrane fouling. Therefore, understanding the reasons for the fluctuations of sludge filterability is important for the efficient operation of MBRs. In this study, a pilot-scale MBR treating municipal wastewater was operated for about 600 days and the variations in sludge filterability were continuously monitored by batch-filtration experiments using the same membranes as in the MBR. To investigate the reasons for the deterioration of sludge filterability, constituents in sludge supernatant were intensively monitored, and the correlations with sludge filterability were determined. The concentration of lipopolysaccharides (LPS) in sludge supernatant exhibited significantly higher correlation with sludge filterability than did conventional indexes (i.e. polysaccharides and proteins). Size fractions affecting MBR sludge filterability were also investigated, and it was suggested that colloidal LPS deteriorated MBR sludge filterability. Based on the long-term operation of the MBR, increase in colloidal LPS under low temperatures of the mixed liquor suspension was a key factor in the deterioration of sludge filterability. The impact of LPS increasing under low temperatures should be investigated by operating bench-scale MBRs fed with synthetic wastewater in controlled conditions
Beschreibung:Date Completed 12.05.2020
Date Revised 15.12.2020
published: Print
Citation Status MEDLINE
ISSN:0273-1223
DOI:10.2166/wst.2020.131