Sedimentation

Description  

This method enables the settling of small, suspended particles (like flocks, sand and clay) in slow-streaming or still water. Installation includes a tank/basin with inlet and outlet structure. Sludge layer is formed at the bottom requiring periodic removal.

Financial  

Both construction costs and O&M costs are low. Specific costs…

Institutional  

Typically applied at municipal treatment plants or at small community level. Limited labor is required for the management. Since sedimentation is applied jointly with other processes (e.g. coagulation/flocculation), caretakers can combine maintenance activities of more installations.

Environmental  

Mainly used for surface water. Tank requires significant amount of surface area. If basin is open, contaminations might blow into water. Sludge needs safe disposal. If put in waste pit, leaching contaminants might affect groundwater sources and pose health risk.

Techical  

Simple to construct, mostly using masonry or concrete. Design inlet arrangement must ensure the even and turbulence-free supply of water in tank to keep settling efficiency high. Regular removal of sludge required. Installation maintenance is minimal. Effluent monitoring required.

Social

Does not require specific actions from users. Since the method is widely known and applied acceptance will be good. Sedimentation does not give the guarantee of safe water, it should always be used in combination with other disinfection processes.

Relevant remarks:

No relevant remarks for Sedimentation.