title: Treatment of oil sands process-affected water using moving bed biofilm reactors: With and without ozone pretreatment.
abstract: Two moving bed biofilm reactors (MBBRs) were operated to treat raw (untreated) and 30 mg/L ozone-treated oil sands process-affected water (OSPW). After 210 days, the MBBR process showed 18.3% of acid-extractable fraction (AEF) and 34.8% of naphthenic acids (NAs) removal, while the ozonation combined MBBR process showed higher removal of AEF (41.0%) and NAs (78.8%). Biodegradation of raw and ozone treated OSPW showed similar performance. UPLC/HRMS analysis showed a highest NAs removal efficiency with a carbon number of 14 and a -Z number of 4. Confocal laser scanning microscopy (CLSM) showed thicker biofilms in the raw OSPW MBBR (97 ± 5 μm) than in the ozonated OSPW MBBR (71 ± 12 μm). Quantitative polymerase chain reaction (q-PCR) results showed higher abundance of gene copies of total bacteria and nitrogen removal relevant bacteria in the ozonated OSPW MBBR, but no significant difference was found. MiSeq sequencing showed Proteobacteria, Nitrospirae, and Acidobacteria were dominant.
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada.
authors.forename: Yijing
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada.
authors.forename: Chunkai
authors.initials: C
authors.lastname: Huang
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada.
authors.forename: Ketley Costa
authors.initials: KC
authors.lastname: Rocha
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada.
authors.forename: Mohamed Gamal
authors.initials: MG
authors.lastname: El-Din
authors.affiliation: Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2W2, Canada. Electronic address: yang.liu@ualberta.ca.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
mesh_terms: D001673:Biodegradation, Environmental; D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors / Q000382:microbiology*; D007220:Industrial Waste / Q000032:analysis; D061329:Oil and Gas Fields / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D007220:Industrial Waste; D014874:Water Pollutants, Chemical; D014867:Water; D010126:Ozone
keywords: Biofilm; Microbial community; Moving bed biofilm reactor (MBBR); Oil sands process-affected water (OSPW); Ozonation