DEFLUORIDATION OF POTABLE WATER BY NALGONDA TECHNIQUE

Fluoride, although beneficial when present in concentrations of 0.8-1. 0 mg/l, has been associated with mottled enamel of teeth when present in potable waters in excess of 1.5 mg/l and skeletal fluorosis beyond 3 mg/l. A simple and effective process, the Nalgonda technique of difl uoridation, has been developed by the National Environmental Engineeri ng Research Institute. The-process has been adapted for defluoridation of potable water at domestic as well as community level. The process details along with design data and cost of defluoridation are discusse d here.