title: Impact of carbon to nitrogen ratio and aeration regime on mainstream deammonification.
abstract: While deammonification of high-strength wastewater in the sludge line of sewage treatment plants has become well established, the potential cost savings spur the development of this technology for mainstream applications. This study aimed at identifying the effect of aeration and organic carbon on the deammonification process. Two 10 L sequencing bath reactors with different aeration frequencies were operated at 25°C. Real wastewater effluents from chemically enhanced primary treatment and high-rate activated sludge process were fed into the reactors with biodegradable chemical oxygen demand/nitrogen (bCOD/N) of 2.0 and 0.6, respectively. It was found that shorter aerobic solids retention time (SRT) and higher aeration frequency gave more advantages for aerobic ammonium-oxidizing bacteria (AerAOB) than nitrite oxidizing bacteria (NOB) in the system. From the kinetics study, it is shown that the affinity for oxygen is higher for NOB than for AerAOB, and higher dissolved oxygen set-point could decrease the affinity of both AerAOB and NOB communities. After 514 days of operation, it was concluded that lower organic carbon levels enhanced the activity of anoxic ammonium-oxidizing bacteria (AnAOB) over denitrifiers. As a result, the contribution of AnAOB to nitrogen removal increased from 40 to 70%. Overall, a reasonably good total removal efficiency of 66% was reached under a low bCOD/N ratio of 2.0 after adaptation.
authors.affiliation: Center for Microbial Ecology and Technology (LabMET), Ghent University, CoupureLinks 653, 9000 Ghent, Belgium; DC WATER, 500 Overlook Ave SW, Washington, DC, USA.
authors.forename: M
authors.initials: M
authors.lastname: Han
authors.affiliation: DC WATER, 500 Overlook Ave SW, Washington, DC, USA.
authors.forename: H
authors.initials: H
authors.lastname: De Clippeleir
authors.affiliation: DC WATER, 500 Overlook Ave SW, Washington, DC, USA.
authors.forename: A
authors.initials: A
authors.lastname: Al-Omari
authors.affiliation: ARAconsult, Unterbergerstr. 1, 6020 Innsbruck, Austria.
authors.forename: B
authors.initials: B
authors.lastname: Wett
authors.affiliation: Center for Microbial Ecology and Technology (LabMET), Ghent University, CoupureLinks 653, 9000 Ghent, Belgium; Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium E-mail: siegfried.vlaeminck@uantwerpen.be.
authors.forename: S E
authors.initials: SE
authors.lastname: Vlaeminck
authors.affiliation: Hampton Road Sanitation District, 1436 Air Rail Ave, Virginia Beach, VA, USA.
authors.forename: C
authors.initials: C
authors.lastname: Bott
authors.affiliation: DC WATER, 500 Overlook Ave SW, Washington, DC, USA.
authors.forename: S
authors.initials: S
authors.lastname: Murthy
mesh_terms: D000641:Ammonia / Q000378:metabolism*; D064751:Ammonium Compounds / Q000378:metabolism*; D001419:Bacteria / Q000378:metabolism*; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D002244:Carbon / Q000032:analysis; D058440:Denitrification; D004784:Environmental Monitoring; D009584:Nitrogen / Q000032:analysis; D012722:Sewage / Q000032:analysis; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000032:analysis
chemical_list: D000641:Ammonia; D064751:Ammonium Compounds; D002244:Carbon; D009584:Nitrogen; D012722:Sewage; D062065:Wastewater