What is the function of a coagulation process in water treatment?

The coagulation process in water treatment plays a crucial role in improving water quality by addressing the removal of small particles that may not be effectively filtered out by conventional methods. During coagulation, coagulants—substances that promote particle aggregation—are added to the water. These coagulants cause small, suspended particles, such as silt, clay, and microorganisms, to clump together into larger aggregates called flocs. This aggregation significantly enhances the ability of subsequent filtration processes to remove these particles from the water.

This process is essential, especially in surface water treatment, where various organic and inorganic materials can lead to turbid water. The effectiveness of coagulation directly influences the clarity and quality of the water entering the disinfection phase. By removing these small particles, coagulation also aids in reducing the load on downstream treatments, making them more efficient and effective.

The other options either address processes not directly related to coagulation or discuss objectives that coagulation does not achieve. Coagulation is specifically designed for particle removal and does not remove dissolved salts, enhance disinfection efficiency directly, or serve as a cooling process.