Analysis of Leachate Characteristics to Study Coal Ash Usability - Management of Natural Resources in a Changing Environment - page 237

Conclusions
The main chemical compositions of coal ash are SiO 2 , Al 2 O 3 , Fe 2 O 3 , CaO and MgO,
in which SiO 2 content is high showing high pozzolanic property. EDXA analysis
indicated the presence of the following elements: Ca, Mg, Al, Na, Si, K, Ti, Fe, C
and O in the coal ash samples. The SEM microphotograph of ash reveals that it is a
mixture of spherical particles of different sizes indicating less surface area. The
concentrations of all the metals, salts and ions under this study of the leachate were
invariably well below the permissible limits for discharge of effl uents as per the
Indian standards. Mixture of fl y ash and pond ash can be utilized as the potential
material as leachability of elements was found to be very low. Long term leaching
tests are required to be studied to understand long term leachate behaviour.
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