title: Characteristics of denitrifying granular sludge grown on nitrite medium in an upflow sludge blanket (USB) reactor.
abstract: While inoculating pre-acclimatized floccular sludge, nitrite-denitrifying granular sludge was obtained after approximately 40 days of cultivation in a 10 L upflow sludge blanket (USB) reactor. The nitrite removal efficiency was approximately 95% when the nitrite concentration was 50 mg L(-1)at an influent flow rate of 20 L h(-1). The nitrite granular sludge had several notable features including good settleability (110 m h(-1)), high ash content (79%), and high density (1.248 g cm(-3)). The mixed liquor suspended solids (MLSS) of the sludge bed remained at 130.04 g L(-1), at a hydraulic upflow velocity of 2 m h(-1). These interesting characteristics were attributed to a high effluent pH (9.7) caused by the release of alkalinity during the nitrite denitrification process. The surfaces of the granules were dominated by cocci bacteria with a diameter of approximately 3 μm, which could be classiﬁed as Nitrosomonas-like species based on our analysis of 16 S rDNA sequences.
authors.affiliation: East China University of Science & Technology, Shanghai, China. xbjin@ecust.edu.cn
authors.forename: Xibiao
authors.initials: X
authors.lastname: Jin
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.forename: Guohong
authors.initials: G
authors.lastname: Liu
authors.forename: Yongdi
authors.initials: Y
authors.lastname: Liu
mesh_terms: D019149:Bioreactors; D058440:Denitrification; D059013:Microbial Consortia; D009573:Nitrites / Q000737:chemistry*; D012722:Sewage
chemical_list: D009573:Nitrites; D012722:Sewage