Characterization of MSWI fly ashes along the flue gas cooling path and implications on heavy metal recovery through acid leaching

This study reports on detailed chemical and mineralogical characterization of the different municipal solid waste incineration ashes forming along flue gas path plants with separate dust removal neutralization. In pursuit optimizing heavy metal recovery through acid leaching, extractability from empty pass (EA), boiler (BOA) electrostatic precipitator (ESPA) was evaluated compared. The focus laid matrix phases affecting leachability (e.g. alkalinity, oxidation–reduction potential), as well distribution concentration recoverable metals their binding forms. data showed, that EA BOA are geochemically similar essentially composed two materials: poor airborne ash particles Zn- Pb-rich sulfate deposits condensate heat exchanger surfaces. Variation in relative amount composition is responsible for fluctuations bulk BOA. ESPA shows characteristics than enriched volatile Zn, Pb, Cu, Cd Sn, which mainly incorporated chlorides sulfates. high content salt-bound thus easily soluble together lower alkalinity potential indicates, has a better compared to BOA, other hand, do not show any significant differences leachability. may contribute basis re-evaluating disposal routes fractions extraction properties.