What is the function of primary treatment in water treatment?

The function of primary treatment in water treatment primarily involves the removal of solids from wastewater. This stage focuses on physical processes to separate larger particles, such as solids and floating materials, from the water. Techniques used during primary treatment include screening to catch large debris, sedimentation to allow heavier solids to settle at the bottom, and flotation processes to remove lighter materials. The goal is to reduce the concentration of suspended solids and organic matter before moving the water to secondary treatment, where biological processes take over.

Disinfection, adjusting pH levels, and filtering out chemicals are all important aspects of water treatment but are characteristic of subsequent phases. Disinfection is primarily conducted to eliminate pathogens and ensure the water is safe for public use; pH adjustment often follows primary treatment to stabilize the water before distribution; and chemical filtration may be utilized later to remove dissolved minerals and contaminants from the water. Therefore, the correct understanding of primary treatment specifically highlights its role in solid removal as a foundational step in the overall water treatment process.