Modeling the major limitations on nitrification in floating-bead filters1
نویسندگان
چکیده
A model was developed and calibrated to experimental data, to formulate a theoretical description of nitrification in bead filters. The model results were consistent with the literature, indicating that the inverse relationship between solids accumulation and nitrification is mediated by an oxygen limitation. This result was central to an explanation of why differing optimal backwash intervals in gentlyand aggressively-washed filters are related to: (1) differences in harvest fraction, which fixes the relationship between backwash interval and interstitial solids concentration and (2) differences in biofilm retention, which controls the average biomass age thereby determining total biomass concentration.
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Developing Backwash Protocols for Floating-Bead Filters: A Model of Solids-Loading and Biofilm-Retention Effects on Nitrification
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