The process for chemo-defluoridation of water and an unit therefor to obtain potable water, involves addition of a combination of chemicals consisting of calcium chloride, calcium phosphate and bleaching powder in one shot, which dissolve in water, react with fluoride to form chemical complex and precipitate out from water. The treated water along with precipitate is passed through sand - gravel filter containing calcium phosphate. The precipitate settled on the sand, further acts as adsorption media and enhances the fluoride removal efficiency. Thus, there is no need to remove this layer from the filter. The precipitate formed due to addition of chemicals is amorphous and does not clog the filter and allows filtration for a period of 4 to 6 months. Another chemical is added for disinfection of water, thus in addition to fluoride removal, the present invention also reduces the microbial contamination in raw water. The taste of the treated water is palatable. The process and unit is suitable for provision of safe potable water in fluoride affected areas, both at domestic as well as community level.[IN-DEL-2008-01242A]
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