TURKIYE JEOLOJI BULTENI-GEOLOGICAL BULLETIN OF TURKEY, vol.63, no.1, pp.43-56, 2020 (ESCI)
Acid mine drainage (AMD) generated by anthropogenic effects has low pH and contains high concentrations of metals, sulfate, dissolved and suspended solids. The Etili coal mine, located within the Can Coal Basin, northwestern Turkey, has been facing environmental problems caused by AMD since the 1980s. As a result of mining activities, fine grain size mine waste with high sulfur content is distributed over large areas around the coal mines and accelerates the AMD formation process. In this study, the aim was to determine the effect of using the fluidized bed thermal power plant waste of fly ash to neutralize AMD and reduce environmental effects caused by mine wastes at the laboratory scale. Based on the results of chemical analysis, paste pH and acid-base accounting tests, it was identified that mine wastes need to be mixed with at least 30% fly ash by weight in order to prevent AMD production. The leach tests prepared according to the determined optimum mixing ratio showed that as the pH value of leachate increased, the electrical conductivity, metal (Al, Fe, Mn, Ni, Pb and Zn) and sulfate concentrations decreased. At the end of 24 h, the metal concentrations of the leachate fell below the permissible limits in the Turkish Water Pollution Control Regulation and there was no increase in metal concentrations of the leachate during 720 h. At the end of 720 h, reductions of 72-97% were identified for the metal concentrations in leachate. In this research, it was determined that the environmental effects of AMD could be minimized by using fly ash.