Trickling Filters and RBCs · Recirculation and Loading
What Is Organic Loading on a Trickling Filter?
Organic loading tells you how much food reaches the media each day, measured by weight. Food here means organic matter, usually measured with the BOD test. For trickling filters, the load is compared with the volume of media. The math box shows how it is figured.
When you compare loads, say whether they use total BOD or soluble BOD. Soluble BOD is the part that passes through a lab filter. Also say whether recirculation is included. Do not compare numbers built from different definitions.
Why do you care? When organic loading runs above design, growth gets thick, the open spaces start to plug, and oxygen runs short. You will see ponding, odors, and higher effluent BOD, and nitrification often stops. When loading runs well below design, the film thins out, but you still need enough flow to keep the media wet.
When the load is high, check whether more units can go in service, whether recirculation helps, and where the extra strength is coming from.
Key point: High organic loading leads to thick growth, plugging, low oxygen, and poorer effluent.
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Trickling Filters and Rotating Biological Contactors
This page comes from the course. It covers biofilm, trickling filter equipment, recirculation and loading, lab tests, sloughing, RBCs and common operating problems, one step at a time, with short knowledge checks and a certificate of completion.
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