Design and Evaluation of Household Horizontal Slow Sand Filter

Abstract

Slow sand filtration has been recognized as an appropriate technology for drinking water treatment in rural areas, and is recognized as a suitable filtration technology in reducing turbidity and coliform concentrations. It is capable of improving the physical, chemical, and microbiological quality of water in a single treatment process without the addition of chemicals, and can produce an effluent low in turbidity and free of bacteria. The objective of this study was thus to develop a household-scale horizontal slow sand filter (HSSF) with a low-cost treatment process, which can be operated and maintained by a member of the families. It therefore involves obtaining different grain sizes of sand as a filter media and water quality data from laboratory after filtering the water in different slopes of the HSSF tool. So, the primary product of this project was the developed recommendations and design criterias for the use of HSSF technology to improve water quality. Accordingly, the developed tool was found capable to produce remarkable results in removing turbidity and coliform concentrations in water. The average percent removal of coliforms was found to be 100% with effect from the 9th day; while, turbidity had become within the permissible limit in the first day of filtration.