Journal of Water, Sanitation and Hygiene for Development Vol 1 No 4 pp213–223 2011 doi:10.2166/washdev.2011.016
Fluoride removal from drinking water in Senegal: laboratory and pilot experimentation on bone char-based treatment
Sabrina Sorlini, Daniela Palazzini and Carlo Collivignarelli
Faculty of Engineering, University of Brescia, via Branze 43, 25123 Brescia, Italy E-mail: sabrina.sorlini@ing.unibs.it
In Senegal there are four regions where fluoride concentration in drinking water exceeds the World Health Organization guide value of 1.5 mg/L. This generates permanent damages to the teeth (dental fluorosis) and to the skeleton (skeletal fluorosis). A safe, efficient, simple and low-cost effective defluoridation technique is not available yet and needs to be developed in order to prevent the occurrence of fluorosis. This experimental research was carried out in order to define an appropriate technology for fluoride removal from groundwater in Senegal. Batch tests and filtration tests at laboratory and pilot scale were carried out using animal bone char as adsorbent material for fluoride removal. Possible influencing parameters, such as specific ions in Senegalese drinking water, were investigated and the best process conditions were defined for the application in Senegal. The results attest to the efficacy of bone char in removing fluoride from Senegalese water: at pilot scale the mean specific adsorption was 2.7 mg F-/g of bone char, corresponding to a total treated volume of 4,000 L and a filter life of nearly three months.