title: Nitrification, denitrification, and dephosphatation capability of activated sludge during co-treatment of intermediate-age landfill leachates with municipal wastewater.
abstract: This study focuses on the possible use and efficacy of the co-treatment of landfill leachate (intermediate-age) with municipal wastewater. The nitrification, denitrification, and dephosphatation capability of activated sludge acclimated with a mixture of raw municipal wastewater (RWW) with gradually increasing amounts of raw landfill leachate (RLL) (from 0.5 to 5% v/v) were tested. Biochemical tests were conducted simultaneously in batch reactors (BRs). According to the obtained data, the ammonia utilization rate (AUR) was 3.68 g N/(kg volatile suspended solids (VSS)·h) for RWW, and it increased to 5.78 g N/(kg VSS·h) with the addition of 5% RLL. The nitrate utilization rate under anoxic conditions (NURAX) remained at a comparable level of 1.55-1.98 g N/(kg VSS·h). During the anoxic phase, both nitrate utilization and phosphorus uptake occurred, suggesting that denitrifying phosphorus-accumulating organisms (DPAOs) utilized N-NO3. With the addition of RLL, the rates of anoxic and aerobic phosphate uptake (PURAXand PURAE) and phosphate release rate (PRR) decreased. The PRR was likely negatively influenced by high N-NO3concentrations but not completely inhibited due to the availability of a biodegradable fraction of chemical oxygen demand (COD). Thus, monitoring the NH4-N load in wastewater treatment plant influent before co-treatment is more informative than that using hydraulic-based criteria.
  
  
  BACKGROUND
  σ - standard deviation; AUR - ammonia utilization rate; DPAO - denitrifying phosphorus-accumulating organisms; MLVSS - mixed liquor volatile suspended solids content; MSW - municipal solid waste; NURAE- nitrate production rate under aerobic conditions; NURAX- nitrate utilization rate under anoxic conditions; PAO - phosphorus-accumulating organisms; PRR - phosphate release rate under anaerobic conditions; PURAX- phosphate uptake rate under anoxic conditions; PURAE- phosphate uptake rate under aerobic conditions; RLL - raw landfill leachates; RM0.5 - raw mixture of RWW with 0.5% (vol.) of RLL; RM3 - raw mixture of RWW with 3% (vol.) of RLL; RM5 - raw mixture of RWW with 5% (vol.) of RLL; RWW - wastewater; VFA - volatile fatty acids; WWTP - wastewater treatment plant.
authors.affiliation: a Faculty of Civil and Environmental Engineering, Department of Sanitary Engineering , Gdansk University of Technology , Gdansk , Poland.
authors.forename: S
authors.initials: S
authors.lastname: Fudala-Ksiazek
authors.affiliation: b Faculty of Civil and Environmental Engineering, Department of Water and Wastewater Technology , Gdansk University of Technology , Gdansk , Poland.
authors.forename: E
authors.initials: E
authors.lastname: Kulbat
authors.affiliation: b Faculty of Civil and Environmental Engineering, Department of Water and Wastewater Technology , Gdansk University of Technology , Gdansk , Poland.
authors.forename: A
authors.initials: A
authors.lastname: Luczkiewicz
mesh_terms: D019149:Bioreactors; D058440:Denitrification; D058465:Nitrification; D009584:Nitrogen; D010758:Phosphorus; D012722:Sewage; D014865:Waste Disposal, Fluid; D062065:Wastewater; D014874:Water Pollutants, Chemical
chemical_list: D009584:Nitrogen; D010758:Phosphorus; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Intermediate-age landfill leachates; co-treatment; kinetics of biochemical processes; municipal wastewater; nitrification–denitrification–dephosphatation