Chemical Examination of Fly Ash and Bottom Ash Derived from Incineration of Hazardous Waste

Abstract

The content of heavy metals in solid residues from the incineration of hazardous waste affects the quality of the environment including soil and water and – most importantly – human health. The chemical composition is often decisive for the further management of the waste, which involves its direct use or conversion into an environmentally safe form. Therefore, the chemical and mineralogical composition of fly and bottom ash from the incineration of hazardous waste was examined. In addition, the results of leaching tests for heavy metals, Cl- and SO4 2- were performed. The obtained results indicate that the dominant components are SiO2, CaO, Al2O3, Fe2O3, SO3 and Cl-. Partitioning was observed for heavy metals such as Cr(III), Cu(II), Zn(II), Ni(II), Pb(II) and Cd(II) between fly ash and bottom ash. The leaching results showed a lower amount of heavy metals in eluates from bottom ash than fly ash as a result of their presence in the glassy phase.