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:Tap water
Denitrification system:Lithotrophic denitrification
Denitrifying reactor:Fluidized-bed
Medium:Silica sand
Culture taken from:Activated sludge
Organism (s) cultured:nan
Respiration:Anaerobic
Electron donor:Thiosulfate-limestone; Thiosulfate-bicarbonate
Electron acceptor:Nitrate
Input NO3-N (mg/l):0.1
Nitrate removal rate (mg NO3-N/l/h):2.9-8.6
Denitrification rate (gNO3-N removed/m3/day):0.72
Microorganisms identified:nan
Molecular tools:nan
Major findings:Methanol was dozed into the reactors stimulating (mixtrophic denitrification) heterotrophic and autotrophic denitrifcation which resulted in the reduction of sulfate generation. When bicarbonate was used as the alkalinity source enhanced the performance of the sulfur based autotrophic denitrification compared to when limestone was used.
Authors:Sahinkaya and Dursun., 2015
Title:Use of elemental sulfur and thiosulfate as electron sources for water denitrification
Pubmed link:Link
Full research link:Link
Abstract:This study aims at comparing the sulfur-based autotrophic and mixotrophic denitrification performances in fixed-bed bioreactors to reveal the impact of alkalinity source, methanol supplementation and use of thiosulfate as electron source. Three different columns were operated. Reactor 1 was packed with elemental sulfur (3–5 mm) and limestone (1–3 mm). The second reactor (reactor 2) was packed with elemental sulfur (3–5 mm) and bicarbonate was used as alkalinity source. In the third reactor (reactor 3), thiosulfate and bicarbonate were used as electron and alkalinity sources, respectively. Nearly complete autotrophic denitrification was attained at loading rates of 0.1, 0.36, and 0.1 g NO3 ?-N/(L day) in reactors 1, 2 and 3, respectively. Sulfate generated in autotrophic denitrification processes was nearly stoichiometric. Stimulating simultaneous heterotrophic and autotrophic denitrification by dozing methanol increased denitrification rate up to 0.72 g NO3 ?-N/(L day), decreased alkalinity requirement, and reduced sulfate generation.