India has a fly ash disposal problem

India produced about 170 million metric tons of fly ash in 2017.  Hundreds of millions of tons are presently stored in ponds which are causing contamination of ground water.

Over a period of last twenty years, the image of fly ash has completely changed from a “hazardous waste” to “resource material”. This is achieved due to the focused thrust provided by Fly Ash Mission (FAM) & through Fly Ash Unit (FAU), Department of Science & Technology (DST) India. Fly ash is being used in all fields whether whole or in parts. It is being used in the form of cement, for road reclamation and low-lying areas (RLLA), road embankments, mine fillings, ash dyke raising, bricks and tiles, agriculture, concrete and others. The major portions of fly ash are being used mainly for civil construction which include cement, mine fillings, concrete, bricks and tiles, road embankments and reclamations.

Indian coals have high ash content about 30-50% in comparison to the coals of other countries. The quantum of fly ash production depends on the types of coal used and the operating parameters of the thermal power plants. By the year 2013-14, about 65,000 acres of land has been already occupied by the ash ponds. While in the current year, 2016-17 the annual production of fly ash in India was about 169.25 MTs and utilization was 107.10 MTs, and about 63 MTs remained unutilized. This huge volume of fly ash requires large areas of land in the form of ash ponds for dumping which may lead to encroachment on agricultural land. Such a huge volume possesses a challenging threat, in the form of usage of land, health and environmental hazards. Other problems related to fly ash disposal includes high disposal costs and potential leaching of toxic heavy metals from the areas of dumped fly ash into surrounding soil or ground water.