What is the coagulation-flocculation process primarily used for?

The coagulation-flocculation process is primarily used to combine small particles into large aggregates, a crucial step in water treatment. In this process, chemicals known as coagulants are added to the water, which neutralize the charges on suspended particles, allowing them to come together—this is the coagulation phase. Following this, flocculation involves gently mixing the water to promote the aggregation of these now neutralized particles into larger clumps called flocs.

These larger aggregates can be more easily removed from the water through sedimentation or filtration, thus improving the overall water quality by reducing turbidity and removing various contaminants. This process is essential for ensuring that water meets safety and aesthetic standards for potable use, as the reduced particle concentration leads to clearer water and minimizes the risk of harmful substances being present.

The other options, such as increasing water temperature, eliminating bacteria, or reducing water hardness, do not align with the primary objective of the coagulation-flocculation process, which focuses specifically on the aggregation of small particles.