Leaching Characteristics of Fluoride from Coal Ash

More than 100 million tonnes of coal fly ash is produced annually in India from combustion of coal in power plants. It is expected that up to 2020 AD about 150 million tonnes of coal ash will be produced due to burning of coal in power plants. This will require about 30,000 hectare of land for ash disposal. One of the main problems in disposing of big quantities of coal ash is the possible leaching of different pollutants, including fluoride. A thorough investigation regarding leaching of fluoride from fly ashes is much essential to know the impact of fluoride due to its leaching from fly ash to ground water as well as surface water. In the present paper, short term and long term leaching studies have been carried out on fly ash, bottom ash, pond ash and weathered ash of Chandrapura thermal power station (CTPS), Jharkhand and Ramagundam thermal power station (RTPS), Andhra Pradesh. The amount of fluoride released in different experiments has been evaluated. A field investigation at Damoda abandoned open cast mine of Bharat Coking Coal Limited, filled with pond ash of CTPS has been done. Concentration of fluoride in ground water beneath the ash filled mine has been evaluated on monthly basis. Environmental impact of fluoride and remedial measures for ash disposal has been discussed.