title: Performance evaluation and bacterial characterization of membrane bioreactors.
abstract: A bench-scale conventional membrane bioreactor (C-MBR), a moving bed membrane bioreactor (MB-MBR) and an anoxic/oxic membrane bioreactor (A/O-MBR), operating under similar feed, environmental and operating conditions, were each evaluated for their treatment performance and bacterial diversity. MBRs were compared for the removal of organics (COD) and nutrients (N and P) while pure culture techniques were employed for bacterial isolation and an API 20E kit was used to identify the isolates. Pseudomonas aeruginosa, selected as a representative of denitrifying microorganisms, was isolated only from the A/O-MBR using Citrimide Agar. Using PCR, the nitrifying bacteria Nitrosomonas europaea was detected only in the MB-MBR. On the other hand, Nitrobacter winogradskyi was detected in all three reactors. Addition of media and maintenance of a lesser DO resulted in the highest TN removal in the A/O-MBR as compared to the C-MBR and the MB-MBR, whereas better nitrification was observed in the MB-MBR than in the C-MBR.
authors: Institute of Environmental Sciences and Engineering, School of Civil and Environmental Engineering, National University of Sciences and Technology, Sector H-12, Islamabad, Pakistan. s.jamal@iese.nust.edu.pk
authors: Sher Jamal
authors: SJ
authors: Khan
authors: Fozia
authors: F
authors: Parveen
authors: Aman
authors: A
authors: Ahmad
authors: Imran
authors: I
authors: Hashmi
authors: Nicholas
authors: N
authors: Hankins
mesh_terms: D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D008567:Membranes, Artificial; D058465:Nitrification; D009576:Nitrobacter / Q000302:isolation & purification / Q000502:physiology; D009584:Nitrogen / Q000032:analysis / Q000737:chemistry; D043370:Nitrosomonas europaea / Q000302:isolation & purification / Q000378:metabolism; D010710:Phosphates / Q000032:analysis / Q000737:chemistry; D010758:Phosphorus / Q000032:analysis / Q000737:chemistry; D012722:Sewage / Q000382:microbiology*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
chemical_list: D008567:Membranes, Artificial; D010710:Phosphates; D012722:Sewage; D010758:Phosphorus; D009584:Nitrogen