title: The correlation between biofilm biopolymer composition and membrane fouling in submerged membrane bioreactors.
abstract: Biofouling, the combined effect of microorganism and biopolymer accumulation, significantly reduces the process efficiency of membrane bioreactors (MBRs). Here, four biofilm components, alpha-polysaccharides, beta-polysaccharides, proteins and microorganisms, were quantified in MBRs. The biomass of each component was positively correlated with the transmembrane pressure increase in MBRs. Proteins were the most abundant biopolymer in biofilms and showed the fastest rate of increase. The spatial distribution and co-localization analysis of the biofouling components indicated at least 60% of the extracellular polysaccharide (EPS) components were associated with the microbial cells when the transmembrane pressure (TMP) entered the jump phase, suggesting that the EPS components were either secreted by the biofilm cells or that the deposition of these components facilitated biofilm formation. It is suggested that biofilm formation and the accumulation of EPS are intrinsically coupled, resulting in biofouling and loss of system performance. Therefore, strategies that control biofilm formation on membranes may result in a significant improvement of MBR performance.
authors.affiliation: a Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing , PR China.
authors.forename: Jinxue
authors.initials: J
authors.lastname: Luo
authors.forename: Jinsong
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Tan
authors.forename: Diane
authors.initials: D
authors.lastname: McDougald
authors.forename: Guoqiang
authors.initials: G
authors.lastname: Zhuang
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Fane
authors.forename: Staffan
authors.initials: S
authors.lastname: Kjelleberg
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Cohen
authors.forename: Scott A
authors.initials: SA
authors.lastname: Rice
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D057219:Biofouling; D001704:Biopolymers / Q000032:analysis / Q000737:chemistry; D019149:Bioreactors / Q000382:microbiology*; D008567:Membranes, Artificial; D011134:Polysaccharides / Q000032:analysis / Q000737:chemistry
chemical_list: D001704:Biopolymers; D008567:Membranes, Artificial; D011134:Polysaccharides
keywords: biofilm; biofouling; cake layer; co-localization; extracellular polymeric substances; transmembrane pressure