Which process is considered to remove suspended solids from water?

The process that is considered effective for removing suspended solids from water is sedimentation. During sedimentation, water is allowed to sit undisturbed in a basin or tank, which encourages suspended solids to settle to the bottom due to gravity. Over time, the heavier particles will fall and form a layer of sludge at the bottom, while clearer water remains above.

In contrast, although filtration, flocculation, and coagulation are also crucial steps in water treatment processes, they serve different primary functions. Filtration primarily focuses on passing water through a medium that captures particulate matter and separates solids from the liquid. Flocculation involves the agglomeration of smaller particles into larger clusters or 'flocs' to make subsequent filtration and sedimentation easier and more effective. Coagulation is the initial step in this process, where chemicals are added to destabilize suspended particles, allowing them to clump together.

Sedimentation is distinctive because it relies on time and gravity rather than the application of mechanical forces or chemical additives, making it a key and straightforward method for reducing suspended solids in water treatment.