title: Denitrification of high strength nitrate waste.
abstract: The aim of the present work was to study the treatment of high strength nitrate waste (40000 ppm NO(3) i.e., 9032 ppm NO(3)-N) by acclimatizing sludge initially capable of degrading dilute streams (100-200 ppm NO(3)-N). Sludge from an effluent treatment plant of a fertilizer industry was acclimatized for 15 d each at 1694, 3388, 6774 and 9032 ppm NO(3)-N in a 4 L sequencing batch reactor. Complete denitrification of extremely concentrated nitrate waste (9032 ppm NO(3)-N) using acclimatized sludge was achieved in just 6 h. During the acclimatization period, increase in nitrite peak value from zero to 5907 ppm NO(2)-N was observed, as the concentration was increased from 1694 to 9032 ppm NO(3)-N. Kinetic analysis of the nitrate and nitrite profile could reasonably support microbiological explanations for nitrite build up and changes in sludge composition.
authors.affiliation: Food and Fermentation Technology Department, Institute of Chemical Technology, University of Mumbai, Matunga, Mumbai 400 019, India.
authors.forename: Pradip B
authors.initials: PB
authors.lastname: Dhamole
authors.forename: Rashmi R
authors.initials: RR
authors.lastname: Nair
authors.forename: Stanislaus F
authors.initials: SF
authors.lastname: D'Souza
authors.forename: S S
authors.initials: SS
authors.lastname: Lele
mesh_terms: D019149:Bioreactors; D005308:Fertilizers; D007220:Industrial Waste; D007700:Kinetics; D017744:Medical Waste Disposal / Q000379:methods*; D009566:Nitrates / Q000737:chemistry* / Q000378:metabolism; D009573:Nitrites / Q000032:analysis; D012722:Sewage / Q000737:chemistry*
chemical_list: D005308:Fertilizers; D007220:Industrial Waste; D017744:Medical Waste Disposal; D009566:Nitrates; D009573:Nitrites; D012722:Sewage