NEERI develops indigenous De-fluoridation kit

June 10, 2012

National Environmental Engineering Research Institute (CSIR-NEERI) has developed indigenous and economically feasible method to reduce high fluoride content in potable water, which has possible domestic and community applications.
The method can be used for reduction of fluoride concentration from 5-8 mg/L to less than 1.0 mg/L (miligram per litre).
The process does not affect the taste of water.
The household unit costs about Rs 2000 and the cost of treatment is around 20 paise/ litre.
The units are appropriate for the small fluoride-affected villages where community water supply schemes are not economically feasible
30 household defluoridation units distributed in Chichkavatha village in Nagpur district in cooperation with the Nagpur Zila Parishad, Sonegaon (Lodhi) Gram Panchayat and Bharat Nirman Cell, Nagpur

Apparatus:

The defluoridation domestic apparatus consists of a steel container fitted with a sand filter at its bottom.

The Process:

The fluoride containing water (30 L) is poured in the container followed by some dose of the salts of calcium and phosphorous chemical coagulants with constant stirring. The salts get dissolved and then get precipitated absorbing fluoride from water. The water along with the precipitate is then passed through the sand filter to collect the treated water with fluoride less than the permissible limit of 1.0 mg/L.

Maintenance:

The filter should be manually cleaned monthly by removing the top layer of the precipitate settled on the sand bed.

What can be harmful effects of excessive fluoride intake?

The excessive fluoride component causes Bone deformations of children, dental fluorosis, toxicity and it is hazardous if it comes in direct contact with skin or eyes.

What is the permissible limit of concentration of Fluoride in water?