Developing Backwash Protocols for Floating-Bead Filters: A Model of Solids-Loading and Biofilm-Retention Effects on Nitrification
نویسندگان
چکیده
Maintaining effective solids capture and nitrification can determine the success or failure of a recirculating aquaculture system (RAS). Although solids capture and nitrification are often performed sequentially, they are united in floating-bead filters. The use of bead filters in a RAS began at the Dworshak National Fish Hatchery (Cooley 1979). More recently, a bead filter was developed and tested by Wimberly (1990) at Louisiana State University (LSU). The Dworshak filter was pneumatically washed whereas LSU’s was hydraulically washed. However, in both filters, increasing the washing frequency enhanced nitrification. These early studies established the importance of abridging solids residence time (SRT).
منابع مشابه
Modeling the major limitations on nitrification in floating-bead filters1
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 ...
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