Which phase of wastewater treatment focuses on the separation of solids from liquid?

The primary treatment phase of wastewater treatment is specifically designed to focus on the separation of solids from liquid. During this initial stage, the main objective is to remove settleable solids and floating materials from the wastewater through physical processes such as sedimentation and flotation. This phase typically involves the use of screening and sedimentation tanks to allow heavier solids to settle to the bottom, forming a sludge layer, while lighter materials rise to the top and can be skimmed off.

The importance of this phase is crucial, as it reduces the organic load and prepares the wastewater for further treatment processes. In contrast, the aeration phase and secondary treatment are more concerned with the biological processes to break down remaining organic matter, while the final disposal phase focuses on the safe disposal or reuse of treated wastewater. By emphasizing the removal of solids, primary treatment plays an essential role in enhancing the overall efficiency and effectiveness of the subsequent treatment stages.