Biological Nitrogen Removal Database

A manually curated data resource for microbial nitrogen removal


Water Treatment Plant


Experimental setup


Influent:Single Household Wastewater

Denitrification system:Sulfur-driven autotrophic denitrification

Denitrifying reactor:Packed-bed

Medium:Charcoal particles

Culture taken from:nan

Organism (s) cultured:nan

Respiration:Aerobic

Electron donor:Sulfur-limestone

Electron acceptor:Nitrate


Experimental Information


Input NO3-N (mg/l):nan

Nitrate removal rate (mg NO3-N/l/h):17–25

Denitrification rate (gNO3-N removed/m3/day):nan

Microorganisms identified:nan

Molecular tools:nan


Information about Article


Major findings:A simple and cost effective treatment techniques was developed based on autotrophic denitrification using sulfur. Their choice of electron donor and pH adjustment is readily available making setup of such a system applicable even in the rural areas. They found that using limestone results in the production of CaSO4- which tends to clogg the pipes. They suggested that for further research one ought to look at replacing limestone with NaOH to adjust the pH.

Authors:Kuai and Verstraete, 1999

Title:Autotrophic Denitrification with Elemental Sulphur in Small-Scale Wastewater Treatment Facilities

Pubmed link:None

Full research link:Link

Abstract:An autotrophic denitrification process with elemental sulphur to achieve a high quality effluent with a low concentration of total N was tested at laboratory scale. Two types of wastewater were tested during a period of 10 months. One was a multiple household wastewater obtained from a municipal wastewater treatment plant and the other was a single household wastewater collected from a family. The wastewaters were first treated by primary sedimentation, followed by nitrifying trickling filtration. The nitrified effluents from the trickling filter were further denitrified in an autotrophic denitrification stage. The autotrophic denitrifying reactor was filled with a mixture of elemental sulphur powder and small pieces of limestone. Sulphur was used as an electron donor and CaCO3 in the limestone served as pH buffer. With a hydraulic retention time of 2–3 hours, up to 86 % of total oxidizable nitrogen (TON) was removed from the multiple household wastewater and 75 % from the single household wastewater. The total N concentration in the final effluents was 3 mg l?1 for the multiple household wastewater and 17 mg l?1 for the single household wastewater. Besides the high removal efficiency and the short hydraulic retention time, other advantages were also noted such as no specific need for inoculum, rapid start up, a wide temperature range for application and low technical labour requirement. Hence, autotrophic denitrification offers interesting potential for removing surplus nitrate from nitrified domestic wastewater particularly in small-scale wastewater treatment facilities.