RESUMO
Defluoridation by adsorption process is well known technique. Though several established techniques are available, they are found to be expensive and labour intensive. Keeping this in view, a study is being done to remove excess fluoride in drinking water based on the concept of adsorption using locally available materials like laterite, sand and gravel. The studies were being conducted in a column with varying depths of laterite by keeping constant gravel depth. The flow is varied for all the depths and the results obtained were found to be quite encouraging as compared to some of the established costly techniques. This technique can be employed in rural areas and places where expensive techniques like electrolytic precipitation, etc. cannot be adopted.