De-fluoridation of groundwater using magnesium oxide

Abstract

Fluorosis, which severely affects teeth and bones, is one of the common water-related diseases listed by the World Health Organization. Fluorosis is caused by ingestion of groundwater containing fluoride in excess of 1.5 mg/l and is widespread in about 25 countries. As majority of fluorosis affected regions occur in arid or semi-arid regions of the world, de-fluoridation of the limited available water resource forms the viable solution. Though several methods of de-fluoridation have been proposed, only few are implemented in field. Further, the existing field methods have various limitations such as cost, efficiency, quality of treated water and disposal of byproducts of treatment. In search of a sustainable solution towards mitigating the fluorosis problem, a new method of de-fluoridation using magnesium oxide has been developed in laboratory. Present study addresses issues that will assist in successful implementation of the new de-fluoridation method in field, using a domestic de-fluoridation unit.

A Review of Fluoride Removal from Groundwater

“…The pH adjustment is done using NaHSO 4 in the bottom container. Using a tap, the potable water can be drawn off from the bottom container [82]. In a further development of this method, Pemmaraju and Rao have used a two stage filter unit with an electric stirrer and layers of cotton cloth to filter out any sludge particles before the pH adjustment step [83,84].…”

“…Using a tap, the potable water can be drawn off from the bottom container [82]. In a further development of this method, Pemmaraju and Rao have used a two stage filter unit with an electric stirrer and layers of cotton cloth to filter out any sludge particles before the pH adjustment step [83,84]. For waters containing different bicarbonate concentrations and fluoride levels the various doses of MgO, CaO, CaCl 2 and NaHSO 4 for pH adjustment are also given [85].…”

A Review of Fluoride Removal From Ground Water by Various Adsorption Techniques

“…In a variation of this method, Mamatha and Rao 46 have used a two stage filter unit with an electric stirrer and layers of cotton cloth to filter out any sludge particles before the pH adjustment step.…”

Groundwater Quality

“…The process achieved over 99% rejection of the salts, arsenic, fluoride, and uranium for polypropylene and polytetrafluoroethylene membranes. Pemmaraju et al (2011) tried magnesium oxide for de-fluoridation in laboratory. This technique could be used in domestic de-fluoridation units.…”