Singh, G; Mishra, S; Sharma, NK
In India, the present management practice of handling coal combustion residue (CCR) :nvolves a combination of two strategies. The first one involves maximum possible utilization in all the avenues followed by the disposal of unutilized CCR as waste in landfill sites. In this study, CCR samples were collected from four different thermal power plants and analyzed for their leaching behavior by short and long term leaching studies. The leachates were found to exist in neutral to slightly alkaline range during the major course of study. Amongst the total twenty-three elements studied for leaching only nine like sodium, potassium, calcium, magnesium, manganese, copper, iron, zinc and lead were observed in leachates. For all the nine leached elements high concentrations were observed initially which reduced considerably with time. Chromium, nickel, cobalt, cadmium, selenium, aluminum, silver, arsenic, boron, barium, vanadium, antimony, molybdenum and mercury were observed to be present below the detection limit (0.01 ppm) during the entire study period of 1100 days. The results obtained further suggest that leaching from CCRs as such do not pose any significant environmental impacts to the water disposal system.
