Determination of the intrinsic kinetic parameters of sulfide-oxidizing autotrophic denitrification in differential reactors containing immobilized biomass

• Published in: Bioresource technology Vol. 104; pp. 250 - 256
• Main Authors: Moraes, B.S., Foresti, E.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-01-2012
• Subjects: Autotrophic denitrification; Bacteria, Anaerobic - metabolism; Biodegradation, Environmental; Bioreactors - microbiology; Cells, Immobilized - physiology; Computer Simulation; Denitrification; Domestic; Equipment Design; Equipment Failure Analysis; Immobilized cells; Intrinsic kinetic parameters; Kinetics; Mathematical models; Metabolic Clearance Rate; Models, Biological; Nitrates; Nitrites; Nitrogen - isolation & purification; Nitrogen - metabolism; Nitrogen removal; Oxidation-Reduction; Reaction kinetics; Reactors; Sulfide; Sulfides; Sulfides - isolation & purification; Sulfides - metabolism; Sulfide; Autotrophic denitrification; Immobilized cells; Intrinsic kinetic parameters
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2011.11.050

► Intrinsic kinetic parameters of sulfide-oxidizing autotrophic denitrification. ► Sulfide as electron donor and nitrate/nitrite as electron acceptors. ► Negligible external and internal mass transfer resistance. ► Half-order kinetic model for biofilm applied to systems with attached cells. ► Intermediary sulfur compounds production from partial sulfide oxidation.
Nitrogen removal coupled with sulfide oxidation has potential for the treatment of effluents from anaerobic reactors because they contain sulfide, which can be used as an endogenous electron donor for denitrification. This work evaluated the intrinsic kinetics of sulfide-oxidizing autotrophic denitrification via nitrate and nitrite in systems containing attached cells. Differential reactors were fed with nitrified synthetic domestic sewage and different sulfide concentrations. The intrinsic kinetic parameters of nitrogen removal were determined when the mass transfer resistance was negligible. This bioprocess could be described by a half-order kinetic model for biofilms. The half-order kinetic coefficients ranged from 0.425 to 0.658mgN1/2L−1/2h−1 for denitrification via nitrite and from 0.190 to 0.609mgN1/2L−1/2h−1 for denitrification via nitrate. In this latter, the lower value was due to the use of electrons donated from intermediary sulfur compounds whose formation and subsequent consumption were detected.