title: Treatment of hypersaline produced water employing a moderately halophilic bacterial consortium in a membrane bioreactor: effect of salt concentration on organic removal performance, mixed liquor characteristics and membrane fouling.
abstract: In this study the organic pollutant removal performance and the mixed liquor characteristics of a membrane bioreactor (MBR), employing a moderately halophilic bacterial consortium, for the treatment of hypersaline synthetic produced water containing 100-250 g L(-1) NaCl were considered. The COD and oil and grease (O&G) removal efficiencies in the range 81.6-94.6% and 84.8-94.0% respectively and MBR effluent turbidity lower than 2NTU were achieved. There was no pronounced membrane fouling at any salt concentration. O&G accumulation (less than 11% of the influent O&G) occurred in the mixed liquor at all salt concentrations, but biodegradation was identified as the major organic removal mechanism. With increasing salt concentration, initially increase in SVI and later formation of oil/biomass bodies took place but due to the presence of the membrane biomass washout did not occur. The mixed liquor was pseudoplastic and the apparent viscosity and flow behavior index generally increased with salt concentration.
authors.affiliation: Department of Chemical Engineering, Amirkabir University of Technology, Tehran, Iran; Department of Energy, Materials and Energy Research Center, Karaj, Iran.
authors.forename: Elham
authors.initials: E
authors.lastname: Abdollahzadeh Sharghi
authors.affiliation: Department of Chemical Engineering, Amirkabir University of Technology, Tehran, Iran. Electronic address: babakb@aut.ac.ir.
authors.forename: Babak
authors.initials: B
authors.lastname: Bonakdarpour
authors.affiliation: Department of Chemical Engineering, Amirkabir University of Technology, Tehran, Iran.
authors.forename: Mehrzad
authors.initials: M
authors.lastname: Pakzadeh
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis; D001673:Biodegradation, Environmental / Q000187:drug effects; D057219:Biofouling; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology*; D008567:Membranes, Artificial; D059013:Microbial Consortia / Q000187:drug effects*; D009930:Organic Chemicals / Q000302:isolation & purification*; D011134:Polysaccharides / Q000032:analysis; D012212:Rheology; D054712:Salinity; D012722:Sewage / Q000382:microbiology; D012965:Sodium Chloride / Q000494:pharmacology*; D014835:Volatilization; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D008567:Membranes, Artificial; D009930:Organic Chemicals; D011134:Polysaccharides; D012722:Sewage; D014874:Water Pollutants, Chemical; D014867:Water; D012965:Sodium Chloride
keywords: Halophilic bacterial consortium; High salt concentration; Hypersaline produced water (PW); Membrane bioreactor (MBR); Morphology