What is the primary purpose of coagulation in water treatment?

The primary purpose of coagulation in water treatment is to create larger particles—known as flocs—from smaller suspended solids in the water. When a coagulant, such as aluminum sulfate or ferric chloride, is added to the water, it causes tiny particles and impurities to clump together. This process improves the sedimentation and filtration processes by increasing the size of the particles, making them easier to remove from the water during subsequent treatment stages.

This larger particle formation is crucial because smaller particles can remain suspended in water longer and are harder to filter out effectively. By enhancing the removal of these particles, coagulation helps to produce clearer and safer drinking water.