California Wastewater Treatment Operator Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The role of a clarifier in a wastewater treatment plant is to separate solids from liquids through the process of sedimentation. In this process, wastewater flows into the clarifier, where the velocity decreases, allowing suspended solids, such as grit, organic matter, and other particulates, to settle to the bottom under the force of gravity. This settled material forms a sludge layer at the bottom of the clarifier, while the clarified water, which has a lower concentration of solids, rises to the top and can then be further treated or discharged.

This function is crucial in wastewater treatment because it helps to remove a substantial amount of suspended solids from the water, contributing to the overall efficiency of the treatment process and helping to ensure that the effluent meets environmental standards before it is released back into the environment. By effectively separating the solid and liquid components, clarifiers play a key role in maintaining the quality of treated wastewater.