Calcium ion on membrane fouling reduction and bioflocculation promotion in membrane bioreactor at high salt shock. (January 2016)

• Record Type: Journal Article
• Authors: Zhang, Haifeng; Fan, Xue; Wang, Bin; Song, Lianfa
• Is Part Of: Bioresource technology. Volume 200(2016)
• Page Start: 535
• Page End: 540
• Publication Date: 2016-01
• Subjects: Membrane bioreactor -- Calcium ion -- Salt shock -- Bioflocculation -- Membrane fouling rate; 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.2015.10.080
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Impact of calcium on membrane fouling and bioflocculation at high salt shock. Distributions of calcium and EPS compositions affected bioflocculation process. Calcium addition was an effective approach to remediate MBR at salt shock. Abstract: Fouling propensity of activated sludge in membrane bioreactor (MBR) is closely related to the disturbance of a salt shock. In this work, the characteristics of membrane fouling and bioflocculation were compared in two laboratory-scale MBRs (one with calcium addition, MBR-Ca, the other without, MBR-C) with a transient salt shock. Particle size distributions, zeta potential, relative hydrophobicity, modified fouling index, the content of polysaccharides, proteins and calcium ions in different layers of sludge were monitored prior to, during and after the salt shock. Comparison with MBR-C showed that the recovery time and fouling rate of MBR-Ca were reduced by 50% and 34%, respectively. Remarkable variations of sludge properties in terms of bioflocculation, such as larger particle sizes, higher relative hydrophobicity and zeta potential, lower polysaccharides in supernatant, higher proteins/polysaccharides ratio in slime and loose bound extracellular polymeric substances, were observed in MBR-Ca after the salt shock.