Splash into Success with the NEHA Wastewater Practice Test 2025 – Dive Deep and Conquer!

The purpose of a rotating biological contactor (RBC) in wastewater treatment is to provide surface area for microbial growth and aeration. RBCs consist of a series of closely spaced discs that are partially submerged in wastewater. As these discs rotate, microorganisms attached to the surface of the discs come into contact with the wastewater, where they break down organic matter.

This design maximizes the exposure of the biofilm to both the wastewater and the air, allowing for efficient nutrient uptake and aerobic digestion of pollutants. The rotation helps ensure the biofilm is adequately aerated and periodically exposed and submerged in the wastewater, enhancing the overall treatment process. The effective combination of microbial growth and aeration is key to the RBC's function in treating wastewater.

Other options do not accurately represent the primary purpose of an RBC. While the device may assist indirectly in some of these functions, such as the potential to impact nutrient levels or assist in removing certain contaminants, its main role is centered on providing a platform for microbial communities to thrive and facilitate aerobic treatment.