title: Pilot and full scale applications of sulfur-based autotrophic denitrification process for nitrate removal from activated sludge process effluent.
abstract: Sulfur-based autotrophic denitrification of nitrified activated sludge process effluent was studied in pilot and full scale column bioreactors. Three identical pilot scale column bioreactors packed with varying sulfur/lime-stone ratios (1/1-3/1) were setup in a local wastewater treatment plant and the performances were compared under varying loading conditions for long-term operation. Complete denitrification was obtained in all pilot bioreactors even at nitrate loading of 10 mg NO3(-)-N/(L.h). When the temperature decreased to 10 °C during the winter time at loading of 18 mg NO3(-)-N/(L.h), denitrification efficiency decreased to 60-70% and the bioreactor with S/L ratio of 1/1 gave slightly better performance. A full scale sulfur-based autotrophic denitrification process with a S/L ratio of 1/1 was set up for the denitrification of an activated sludge process effluent with a flow rate of 40 m(3)/d. Almost complete denitrification was attained with a nitrate loading rate of 6.25 mg NO3(-)-N/(L.h).
authors.affiliation: Istanbul Medeniyet University, Bioengineering Department, Goztepe, Istanbul, Turkey. Electronic address: erkansahinkaya@yahoo.com.
authors.forename: Erkan
authors.initials: E
authors.lastname: Sahinkaya
authors.affiliation: Yeditepe Treatment Company, Kucukbakkalkoy, Ataşehir, Istanbul, Turkey.
authors.forename: Adem
authors.initials: A
authors.lastname: Kilic
authors.affiliation: Yeditepe Treatment Company, Kucukbakkalkoy, Ataşehir, Istanbul, Turkey.
authors.forename: Bahadir
authors.initials: B
authors.lastname: Duygulu
mesh_terms: D052818:Autotrophic Processes; D019149:Bioreactors; D009566:Nitrates / Q000378:metabolism*; D010865:Pilot Projects; D012722:Sewage / Q000032:analysis*; D013455:Sulfur / Q000378:metabolism*; D013696:Temperature; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D009566:Nitrates; D012722:Sewage; D014874:Water Pollutants, Chemical; D013455:Sulfur
keywords: Autotrophic denitrification; Elemental sulfur; Nitrate removal; Post denitrification; Wastewater treatment