Treatment of swine wastewater in continuous activated sludge systems under different dissolved oxygen conditions: Reactor operation and evaluation using modelling
Résumé
Swine wastewater was treated in two continuously aerated activated sludge (AS) systems at high (AS1: 1.7'2.6 mg/L) and low (AS2: 0.04'0.08 mg/L) dissolved oxygen (DO), and at three temperatures (10, 20, and 30 °C). Biochemical oxygen demand (BOD) removal was >94.8%. Meanwhile, total nitrogen (N) removal was significantly higher in AS2, at 64, 89, and 88%, than in AS1, at 12, 24, and 46%, for 10, 20, and 30 °C, respectively. The experimental data were considered in a simulation study using an AS model for BOD and N removal, which also included nitrite, free ammonia, free nitrous acid, and temperature. Simulations at high-DO showed that ammonium was partly oxidized into nitrate but not removed, whereas at low-DO ammonium was removed mainly through the nitrite shortcut in simultaneous nitrification'denitrification. This study demonstrates that treatment at low-DO is an effective method for removing N, and modelling a helpful tool for its optimization. © 2017 Elsevier Ltd
Mots clés
ACTIVATED SLUDGE MODEL (ASM)
NITRITE SHORTCUT
SIMULTANEOUS NITRIFICATION AND DENITRIFICATION (SND)
ACTIVATED SLUDGE PROCESS
BIOCHEMICAL OXYGEN DEMAND
DENITRIFICATION
OXYGEN
WASTEWATER TREATMENT
ACTIVATED SLUDGE MODEL(ASM)
ACTIVATED SLUDGE SYSTEMS
BIOCHEMICAL OXYGEN DEMANDS (BOD)
FREE NITROUS ACIDS
SIMULTANEOUS NITRIFICATION AND DENITRIFICATION
DISSOLVED OXYGEN
ACTIVATED SLUDGE
POLLUTANT REMOVAL
TEMPERATURE EFFECT
ARTICLE
EVALUATION STUDY
HIGH TEMPERATURE
NONHUMAN
OXIDATION
PIG
PIG FARMING
PRIORITY JOURNAL
PROCESS OPTIMIZATION
REACTOR OPERATION
WASTE COMPONENT REMOVAL
WASTE WATER
WASTE WATER MANAGEMENT