title: Enrichment and biofilm formation of Anammox bacteria in a non-woven membrane reactor.
abstract: An innovative reactor configuration for Anammox enrichment by connecting a non-woven membrane module with an anaerobic reactor was developed in this study. The Anammox non-woven membrane reactor (ANMR) exhibited high biomass retention ability through the formation of aggregates in the reactor and biofilm on the interior surface of the non-woven membrane. No fouling problems occurred on the membrane after the development of mature biofilms. After 8 months of operation, the nitrogen loading rate (NLR) and nitrogen removal rate (NRR) reached 1263 mg N/l/d and 1047.5 mg N/l/d, respectively, with a maximum specific ammonium consumption (SAC) of 51 nmol/mg protein/min. At steady state, the average ammonium and nitrite removal efficiencies were 90.9% and 95.0%, respectively. Morphological observation of Anammox aggregates and biofilm showed a high degree of compactness. Also, enrichment of Anammox bacteria was quantified by real-time polymerase chain reaction (PCR) analysis as 97.7%.
authors.affiliation: School of Environmental Science and Engineering, Shandong University, Jinan Shandong 250100, China.
authors.forename: Shou-Qing
authors.initials: SQ
authors.lastname: Ni
authors.forename: Po-Heng
authors.initials: PH
authors.lastname: Lee
authors.forename: Anania
authors.initials: A
authors.lastname: Fessehaie
authors.forename: Bao-Yu
authors.initials: BY
authors.lastname: Gao
authors.forename: Shihwu
authors.initials: S
authors.lastname: Sung
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D018441:Biofilms; D019149:Bioreactors / Q000382:microbiology*; D004269:DNA, Bacterial / Q000378:metabolism; D004867:Equipment Design; D008567:Membranes, Artificial; D008854:Microscopy, Electron / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D009573:Nitrites / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry; D016133:Polymerase Chain Reaction; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
chemical_list: D004269:DNA, Bacterial; D008567:Membranes, Artificial; D009573:Nitrites; D000644:Quaternary Ammonium Compounds; D009584:Nitrogen