Sedimentation is the next step in conventional filtration plants. (Direct filtration plants omit this step.) The purpose of sedimentation is to enhance the filtration process by removing particulates. Sedimentation is the process by which suspended particles are removed from the water by means of gravity or separation. In the sedimentation process, the water passes through a relatively quiet and still basin. In these conditions, the floc particles settle to the bottom of the basin, while “clear” water passes out of the basin over an effluent baffle or weir. Sedimentation involves one or more basins, called “clarifiers.” Clarifiers are relatively large open tanks that are either circular or rectangular in shape.
Types of Sedimentation and Clarification: