Trickling Filters and RBCs · Rotating Biological Contactors
How Does a Rotating Biological Contactor Work?
You now know how a trickling filter works, how you load it, how you test it, and how you handle its solids. The RBC is the other common fixed-film unit, and all of that applies here too. A rotating biological contactor, or RBC, is an attached-growth reactor. Plastic media is mounted on a level shaft above a tank. Part of the media sits in the wastewater while the shaft turns slowly.
As the shaft turns, the biofilm passes through the wastewater and then up into the air. In the water, the biofilm picks up food and nutrients. In the air, it picks up oxygen. Turning also mixes the tank and helps shed extra growth.
An RBC system may have several shafts set up in stages. Wastewater moves from an early stage to a later stage. Each stage grows a biofilm that fits the load left in the water at that point.
Operators must check both the treatment and the machines. RBCs use little power and are simple to run, but they rely on one heavy shaft that can fail, and the first stage is easy to overload. A healthy biofilm cannot work if the shaft stops.
Key point: An RBC moves its biofilm between wastewater and air while the flow passes through treatment stages.
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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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