title: Sequential Anaerobic/Aerobic Digestion for Enhanced Carbon/Nitrogen Removal and Cake Odor Reduction.
abstract: Anaerobic digestion (AD) has been proven to be an effective process for the treatment of wastewater sludge. However, it produces high levels of ammonia in the digester effluent, which may jeopardize meeting stringent nutrient discharge limits. In this study, the effect of a sequential anaerobic/aerobic (AN/AERO) digestion and a single-stage conventional AN digestion (as control) was investigated on mixed (primary + secondary) sludge generated by the Annacis Island wastewater treatment plant (WWTP) (BC, Canada). An overall sludge retention time (SRT) of 22.5 days under three different scenarios was chosen based on the current operational SRT of the digesters at the Annacis Island WWTP. The steady state results have shown that sequential AN/AERO digestion configurations achieved up to 11% higher volatile solids (VS) removal and 72% lower ammonia generation over single-stage conventional AN digestion. Furthermore, sequential AN/AERO system also showed enhanced dewaterability, improved fecal coliform destruction and reduced digested cake odors over control digesters.
authors.affiliation: University of British Columbia (UBC) Bioreactor Technology Group, School of Engineering, Okanagan Campus, Kelowna, BC, Canada.
authors.forename: Muneer
authors.initials: M
authors.lastname: Ahmad
authors.forename: Marco Abel
authors.initials: MA
authors.lastname: Denee
authors.forename: Hao
authors.initials: H
authors.lastname: Jiang
authors.forename: Cigdem
authors.initials: C
authors.lastname: Eskicioglu
authors.forename: Paul
authors.initials: P
authors.lastname: Kadota
authors.forename: Theresa
authors.initials: T
authors.lastname: Gregonia
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D001419:Bacteria / Q000378:metabolism*; D019149:Bioreactors; D002244:Carbon / Q000737:chemistry / Q000378:metabolism*; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism*; D009812:Odorants; D013457:Sulfur Compounds / Q000737:chemistry
chemical_list: D013457:Sulfur Compounds; D002244:Carbon; D009584:Nitrogen