About

• Fly ash is a fine gray powder consisting mostly of spherical, glassy particles that are produced as a byproduct in coal-fired power stations. 
• Fly ash has pozzolanic properties, meaning that it forms cement in the presence of water. 

Issues with Fly ash

• Fly ash is a highly toxic substance known for causing health and environmental problems. It can contain lead, arsenic, mercury, cadmium, and uranium. 
• When fly ash is deposited in water bodies they contaminate aquaculture and may leach into landmasses, leading to toxicity of agricultural land and drinking water.
• Fly ash cannot be disposed-off in the open field because it pollutes the air, soil and groundwater.
• Long inhalation of fly ash causes serious respiratory problems.
• Fly ash also causes siltation problems.

Uses of Fly ash

• Fly ash composition, rich in silicon dioxide (SiO2), calcium oxide (CaO), and aluminum oxide (Al2O3), makes it valuable for various applications, transforming potential waste into useful material.
• Fly ash can be used as prime material in many cement-based products, such as poured concrete, concrete block, and brick. 
• One of the most common uses of fly ash is in Portland Cement Concrete pavement or PCC pavement. 
• Road construction projects using PCC can use a great deal of concrete, and substituting fly ash provides significant economic benefits. 
• Fly ash can be used in reclamation of wastelands and wastewater treatment.
• Fly ash has also been used as an embankment and mine fill.

Regulations in India

• Prohibiting dumping and disposal of fly ash discharged from coal or lignite based thermal power plants on land or into water bodies, the Centre has made it mandatory for such plants to ensure 100% utilization of ash in an eco-friendly manner.
• The centre has also introduced a penalty regime for non-compliance based on the ‘polluter pays’ principle.
• The Ministry of Environment, Forest and Climate Change has made it mandatory for all agencies (government, semi-government and private), engaged in construction activities within 300 kms from the lignite or coal based thermal power plants, to utilize ash in these activities.