Leaching Potential of Fly Ash
The present study has been carried out to assess the leaching potential of fly ash by open column experiment. Fly ash was collected from Parichha thermal power plant, Jhansi. The leachability of fly ash in aqueous environment for the major and trace elements was determined. The concentration of leachable ions was found in the descending order as Ca > Mg > K >Ni > Fe > Al > Mn > Cu > Si > Pb > Co > Zn > Cr > Ba. During the entire leaching period, the concentration of calcium and potassium did not change significantly into leachate with respect to pH variation and was found to be pH independent. However, the leached out concentration of Mg, Mn, Ni and Co was found to be maximum under slightly acidic condition. The concentration of leached out elements like Zn, Al, Cu, Ba, Pb, Fe and Si was found to be maximum under both acidic and alkaline conditions while chromium was found to be maximum under alkaline condition.
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