title: Oxygen uptake rate tests to evaluate integrated fixed film activated sludge processes.
abstract: A modified oxygen uptake rate (OUR) test for characterizing the performance of integrated fixed-film activated sludge (IFAS) processes was developed while monitoring the startup of a full-scale demonstration facility. Data on total biofilm solids, in-basin nitrification rates, and batch nitrification rates were compared to the OUR test. The data was used to investigate dynamic changes in the physical and microbiological parameters during and after plant startup. Nitrification of the carriers was observed to follow different trends than the biofilm total solids during process startup. The process reached high nitrification rates within weeks, whereas the biofilm total solids required more than 50 days to attain a quasi-steady-state. This study illustrated that parameters in addition to biofilm total solids are required to assess activity in nitrifying IFAS processes and oxygen uptake rates can be a useful tool in this regard.
authors.affiliation: Hydroxyl Systems Inc., 26 Bastion Square, Victoria BC, Canada, V8W 1H9. clamaas@gmail.com
authors.forename: Carol L A
authors.initials: CL
authors.lastname: Maas
authors.forename: Wayne J
authors.initials: WJ
authors.lastname: Parker
authors.forename: Raymond L
authors.initials: RL
authors.lastname: Legge
mesh_terms: D001673:Biodegradation, Environmental; D018441:Biofilms; D018533:Biomass; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism*; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid; D018508:Water Purification
chemical_list: D009566:Nitrates; D009573:Nitrites; D012722:Sewage; D010100:Oxygen