title: Effects of membrane orientation on fouling characteristics of forward osmosis membrane in concentration of microalgae culture.
abstract: Application of forward osmosis (FO) membrane to microalgae cultivation processes enables concentration of microalgae and nutrients with low energy consumption. To understand fouling characteristics of FO membrane in concentration of microalgae culture, we studied flux decline, flux recovery by cleaning, and foulants characteristics, in different membrane orientation of active-layer-facing-feed-solution (AL-FS) and active-layer-facing-draw-solution (AL-DS) modes. Batch concentration of Chlorella vulgaris was conducted with a cellulose-triacetate FO membrane. Rapid flux decline and lower flux recovery was observed in AL-DS mode because of inner-membrane fouling including internal pore clogging, adsorption and internal concentration polarization in the support layer. A proportion of polysaccharides in extracellular polymeric substances to soluble microbial products were larger in chemical cleaning effluent than physical one in AL-DS mode, although those were not significantly different in AL-FS mode. Excitation-emission matrix analysis revealed that proteins and humic-like substances were also possible irreversible foulants both in AL-DS and AL-FS modes.
authors.affiliation: Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. Electronic address: rhonda@se.kanazawa-u.ac.jp.
authors.forename: Ryo
authors.initials: R
authors.lastname: Honda
authors.affiliation: Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
authors.forename: Weerapong
authors.initials: W
authors.lastname: Rukapan
authors.affiliation: School of Environmental Design, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Komura
authors.affiliation: Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Teraoka
authors.affiliation: Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
authors.forename: Mana
authors.initials: M
authors.lastname: Noguchi
authors.affiliation: Department of Civil and Environmental Engineering, University of California, Los Angeles, CA 90095-1593, USA.
authors.forename: Eric M V
authors.initials: EM
authors.lastname: Hoek
mesh_terms: D000327:Adsorption; D017756:Aquaculture / Q000295:instrumentation / Q000379:methods; D061249:Batch Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods; D002482:Cellulose / Q000031:analogs & derivatives; D048408:Chlorella vulgaris / Q000254:growth & development*; D008567:Membranes, Artificial; D058086:Microalgae / Q000254:growth & development*; D009995:Osmosis; D011134:Polysaccharides / Q000737:chemistry; D012996:Solutions
chemical_list: D008567:Membranes, Artificial; D011134:Polysaccharides; D012996:Solutions; D002482:Cellulose; C024671:cellulose triacetate
keywords: Extracellular polymeric substances (EPS); Forward osmosis; Membrane fouling; Microalgae