Impact of solid retention time and nitrification capacity on the ability of activated sludge to remove pharmaceuticals.
Removal of five acidic pharmaceuticals (ibuprofen, ketoprofen, naproxen, diclofenac and clofibric acid) by activated sludge from five municipal activated sludge treatment processes, with various sludge ages and nitrification capacities, was assessed through batch experiments. The increase in aerobic sludge age from 1-3 to 7 d seemed to be critical for the removal ofnaproxen and ketoprofen, with markedly higher rates of removal at sludge ages of 7 d or more. No removal was shown for diclofenac and clofibric acid, whereas high rates were observed for ibuprofen in all investigated sludges. Parallel examinations of activated sludge batches with and without allylthiourea (12 mg/L), an inhibitor ofammonia monooxygenase, showed minor to moderate influence on the removal rates of ketoprofen and naproxen. These results suggest that the removal rates of biodegradable pharmaceuticals in municipal activated sludge processes are strongly linked to the heterotrophic bacteria community.
Water and Environmental Engineering, Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund. per.falas@chemeng.lth.se
P
P
Falås
H R
HR
Andersen
A
A
Ledin
J la Cour
Jl
Jansen
D001419:Bacteria / Q000378:metabolism; D019149:Bioreactors; D058465:Nitrification; D010100:Oxygen / Q000378:metabolism; D010101:Oxygen Consumption; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology; D013890:Thiourea / Q000031:analogs & derivatives / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D004364:Pharmaceutical Preparations; D012722:Sewage; D014874:Water Pollutants, Chemical; C009842:allylthiourea; D013890:Thiourea; D010100:Oxygen