title: High-rate biological denitrification in the cyclic rotating-bed biological reactor: Effect of COD/NO3(-), nitrate concentration and salinity and the phylogenetic analysis of denitrifiers.
abstract: The effects of COD/NO3(-) ratio, nitrate concentration and salinity was tested on the performance of the CRBR in denitrification with catechol as carbon source. The maximum nitrate reduction attained at COD/NO3(-) ratio of 1. The CRBR operated at optimum COD/NO3(-) ratio could completely denitrify the nitrate at inlet concentration up to 1250mg/L without nitrite accumulation. The maximum denitrification rate in the CRBR was 3.56kgNO3(-)/m(3)d with a nitrate reduction efficiency of 99% when the bioreactor was operated at inlet nitrate loading rate of 3.6kgNO3(-)/m(3)d. The denitrification performance of the CRBR was not affected significantly by NaCl concentrations up to 20g/L. 16S rRNA fragment and phylogenetic analysis identified Pseudomonas resinovorans, Stenotrophomonas maltophilia and Bacillus cereus as the most abundant denitrifiers in biomass. Accordingly, the CRBR is a high-rate bioreactor and appropriate technology for treatment of nitrate-laden industrial wastewaters containing phenolic compounds and salinity.
authors.affiliation: Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Seyed Javad
authors.initials: SJ
authors.lastname: Jafari
authors.affiliation: Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address: moussavi@modares.ac.ir.
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Moussavi
authors.affiliation: Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Center for Water Quality Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Kamyar
authors.initials: K
authors.lastname: Yaghmaeian
mesh_terms: D018441:Biofilms; D057919:Biological Oxygen Demand Analysis; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology*; D002244:Carbon / Q000378:metabolism; D002396:Catechols / Q000378:metabolism; D058440:Denitrification; D059013:Microbial Consortia / Q000235:genetics; D009566:Nitrates / Q000032:analysis / Q000378:metabolism*; D009573:Nitrites / Q000032:analysis / Q000378:metabolism; D009589:Nitrogen Oxides / Q000032:analysis; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S; D054712:Salinity; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods; D062065:Wastewater / Q000737:chemistry
chemical_list: D002244:Carbon; D002396:Catechols; D009566:Nitrates; D009573:Nitrites; D009589:Nitrogen Oxides; D012336:RNA, Ribosomal, 16S; D062065:Wastewater; C034221:catechol
keywords: Biological denitrification; Cyclic reactor; Rotating bed; Salinity