Trickling Filters and RBCs · Fixed-Film Treatment
What Is Attached-Growth Wastewater Treatment?
Trickling filters and rotating biological contactors, or RBCs, use attached-growth treatment. In this kind of process, microbes live on a solid surface. They do not mainly float in the wastewater. The surface may be rock, shaped plastic media, or plastic discs that turn on a shaft. Media is the solid material that gives the microbes a place to grow.
The layer of microbes on the media is called a biofilm. Wastewater flows across the biofilm. Food in the water, such as dissolved organic matter, moves into the film. The microbes use that food for energy and growth. Oxygen supports the microbes near the surface of the film. Deeper in the film, conditions can be different.
The operator manages the conditions around the biofilm. Flow, load, spreading of the water, air supply, rotation, temperature, and solids removal all affect results. You cannot control each microbe. You can protect the conditions that keep the useful microbes active.
Key point: Fixed-film treatment works by bringing wastewater, oxygen, and an attached biofilm into steady contact.
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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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