Ontario Operator-in-Training (OIT) Practice Exam

Rotating biological contactors (RBCs) are specifically designed to support the attached growth of microorganisms, which is key to their operational function. In an RBC system, a series of discs or media are partially submerged in wastewater, allowing for the biofilm of microorganisms to grow on the surface of the discs. As the discs rotate through the wastewater, the microorganisms interact with the organic matter in the water, facilitating the biological treatment process.

This interaction promotes the breakdown of pollutants, as the microorganisms metabolize the organic material. The design of RBCs enables oxygen transfer during the rotation, enhancing the aerobic digestion of wastewater. This is critical in biological treatment processes, ensuring that contaminants are effectively broken down and cleaned from the water.

Understanding the role of the biofilm and its growth on the media is essential, as it contributes to the overall efficiency of waste treatment in various water and wastewater management applications.