Fouling of reverse osmosis membranes by biopolymers in wastewater secondary effluent: Role of membrane surface properties and initial permeate flux

Qilin Li*, Zhihua Xu, Ingo Pinnau

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

271 Scopus citations

Abstract

Reverse osmosis (RO) is being increasingly used in treatment of domestic wastewater secondary effluent for potable and non-potable reuse. Among other solutes, dissolved biopolymers, i.e., proteins and polysaccharides, can lead to severe fouling of RO membranes. In this study, the roles of RO membrane surface properties in membrane fouling by two model biopolymers, bovine serum albumin (BSA) and sodium alginate, were investigated. Three commercial RO membranes with different surface properties were tested in a laboratory-scale cross-flow RO system. Membrane surface properties considered include surface roughness, zeta potential, and hydrophobicity. Experimental results revealed that membrane surface roughness had the greatest effect on fouling by the biopolymers tested. Accordingly, modified membranes with smoother surfaces showed significantly lower fouling rates. When Ca2+ was present, alginate fouled RO membranes much faster than BSA. Considerable synergistic effect was observed when both BSA and alginate were present. The larger foulant particle sizes measured in the co-existence of BSA and alginate indicate formation of BSA-alginate aggregates, which resulted in greater fouling rates. Faster initial flux decline was observed at higher initial permeate flux even when the flux was measured against accumulative permeate volume, indicating a negative impact of higher operating pressure.

Original languageEnglish (US)
Pages (from-to)173-181
Number of pages9
JournalJournal of Membrane Science
Volume290
Issue number1-2
DOIs
StatePublished - Apr 1 2007

Keywords

  • Hydrophobicity
  • Membrane fouling
  • Polysaccharide
  • Protein
  • Reverse osmosis
  • Roughness
  • Surface modification
  • Wastewater reclamation
  • Zeta potential

ASJC Scopus subject areas

  • Biochemistry
  • Materials Science(all)
  • Physical and Theoretical Chemistry
  • Filtration and Separation

Fingerprint

Dive into the research topics of 'Fouling of reverse osmosis membranes by biopolymers in wastewater secondary effluent: Role of membrane surface properties and initial permeate flux'. Together they form a unique fingerprint.

Cite this