New Approach to Understand the Removal Efficiency of Some Anions in Well Water by Slow Sand Filtration

Aims: Slow sand filtration (SSF) is a simple technique widely used for the treatment of drinking water. However, little attention has been accorded to the improvement of the understanding of this process model. The main objective of this work is to develop a numerical tool allowing the prediction and the evaluation of the efficiency of slow sand filtration to decontaminate contaminated well water.

Materials and Methods: This evaluation was done by comparing data from contaminated well water filtered through the laboratory columns with the same diameter (5 cm) but filled with sand to various heights (5 cm, 10 cm and 15 cm).

Results: Decontamination efficiency of slow sand filtration was determined in terms of selected physicochemical parameters such as sulphates, chlorides and total hardness. Results indicated significant difference in levels of sulphates and chlorides in filtered water through the three sand bed heights whereby decontamination efficiency of these parameters was found to be better at the highest sand bed (15 cm).