Heavy metals in Indian coals and corresponding fly‐ash and their relationship with particulate size

Pulverised coal and corresponding fly‐ash collected from the stack precipitator of thermal power plants were analysed for eight heavy metals. Fly‐ash was separated into various sized fractions which were then chemically characterized. The fly‐ash contained higher concentrations of heavy metals with respect to their coal. Except in the case of Pb, Cd and Co, the heavy metals were more concentrated in the <53 μm than in the >150 μm fraction. For the probable contribution of these metals to atmospheric emission and waste ash, it is necessary to estimate the enrichment factors from coal to fly‐ash.