Biological Nitrogen Removal Database
A manually curated data resource for microbial nitrogen removal
Biological Nitrogen Removal Database
A manually curated data resource for microbial nitrogen removal
Influent:Synthetic water
Denitrification system:Simultaneous Desulfurization and Denitrification (SDD)
Denitrifying reactor:Stirred tank
Medium:Walnut husk
Culture taken from:Activated sludge
Organism (s) cultured:nan
Respiration:Anaerobic
Electron donor:Sulfide
Electron acceptor:Nitrate
Input NO3-N (mg/l):0.8
Nitrate removal rate (mg NO3-N/l/h):0.6
Denitrification rate (gNO3-N removed/m3/day):nan
Microorganisms identified:Thiobacillus denitrificans D4
Molecular tools:nan
Major findings:An innovative process of simultaneous desulfurization and denitrification (SDD) was developed to obtain sulfur from sulfide using Thiobacillus denitrificans a bacterial species that oxidizes sulfide into sulfur when nitrate is used as the electron acceptor. It is reported that in organic wastewater plants there is high concentrations of sulfate and nitrate present which poses serious health and environmental hazards. The SDD is an attractive solution for the removal of sulfate and nitrate from water bodies that needs to be explored.
Authors:Wang et al., 2005
Title:An innovative process of simultaneous desulfurization and denitrification by Thiobacillus denitrificans.
Pubmed link:Link
Full research link:Link
Abstract:Thiobacillus denitrificans, a species of autotrophic facultative anaerobic bacterium, was found to be capable of oxidizing sulfide into elemental sulfur when nitrate was adopted as its electron acceptor and carbon dioxide as its sole carbon source under anoxic conditions. In this way, sulfur was accumulated extracellularly and nitrate was converted into nitrogen gas. Based on these special physiological characteristics, an innovative process of simultaneous desulfurization and denitrification (SDD) was developed to obtain sulfur from sulfide. A strain of T. denitrificans, named D(4), was isolated and used as sulfur producers in this study. The stoichiometric equations of SDD by T. denitrificans were also derived. The key factors affecting this process were investigated through continuous-flow and batch tests. The experimental results indicated that both the sulfide concentration and the ratio of S2-/NO3- in the influent are key factors. Their suitable levels are suggested to be controlled less than 300 mg/L and 5/3-5/2, respectively, to achieve a high sulfur conversion degree.