Novel insights into membrane fouling caused by gel layer in a membrane bioreactor: Effects of hydrogen bonding. (March 2019)

• Record Type: Journal Article
• Authors: Chen, Yifeng; Teng, Jiaheng; Shen, Liguo; Yu, Genying; Li, Renjie; Xu, Yanchao; Wang, Fangyuan; Liao, Bao-Qiang; Lin, Hongjun
• Is Part Of: Bioresource technology. Volume 276(2019)
• Page Start: 219
• Page End: 225
• Publication Date: 2019-03
• Subjects: Membrane fouling -- Membrane bioreactor -- Gel layer -- Hydrogen bonding -- Filtration resistance; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2019.01.010
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Specific filtration resistance (SFR) of gel was as high as 2.06 × 10 19 m −1 ·kg −1 at 20 °C. SFR of real gel in MBR and model PNIPAM gel decreased with temperature increase. FTIR analysis indicated a decrease trend of hydrogen bonding strength with temperature. A new mechanism depicting roles of hydrogen bonding in gel filtration was proposed. Contribution level of hydrogen bonding to total gel SFR was quantified to be around 20%. Abstract: Gel layer formation in some cases directly determines membrane fouling extent in membrane bioreactors (MBRs). While hydrogen bonding interactions extensively exist in gelling foulants and sludge suspension, their exact roles in fouling remain unveiled. Filtration results in this study showed that, specific filtration resistance (SFR) of a gel layer formed in the MBR was as high as 2.06 × 10 19 m −1 ·kg −1 at 20 °C, and moreover, SFR of both the real gel and model gel (Poly(N-isopropylacrylamide) (PNIPAM)) decreased with temperature. Fourier-transform infrared spectroscopy (FTIR) analysis indicated that gel samples were abundant of good hydrogen bonding donors/acceptors to form hydrogen bonding, and hydrogen bonding strength decreased with temperature. From viewpoint of free energy, mathematical models depicting roles of hydrogen bonding were proposed. For the first time, contribution level of hydrogen bonding effects to total gel SFR was quantified to be around 20%. These results offered in-depth insights into membrane fouling in MBRs.