The corrosion behavior of glass and glass-ceramics fabricated with silicate glass frit mixed
with 50~70 wt% EAF dust in the acidic solution was analyzed by both heavy metal leaching test and
microstructural observation. The crystallization temperature, Tc of glassy specimens was around 850
measured by DTA and the heat treatment temperature to crystallize a glassy specimen was selected
as 950 / 1 hr. The spinel crystal peaks were found in XRD analysis for the glass containing dust >
60 wt%. For the glass-ceramics, however, the spinel peaks in a specimen containing dust > 50 wt%
was found with weak willemite peaks. The glass and glass-ceramic specimens showed the first stage
of corroding reaction according to Clark models in acidic solution. The glass-ceramic specimens
showed much lower a heavy metal leaching concentration than that of glass specimens in the
corrosion test in acidic solution of pH=2.95. Especially, the glass-ceramics containing dust 60 wt%
showed a heavy metal leaching concentration of 66 % Pb, 60 % Zn and 98 % Fe lower than that of
glass specimens due to crystal phases formed, thermodynamically more stable than a glass network
structure. From the leaching test that more Zn ion leached out than Fe ion, the spinel crystal phase
[ZnFe2O4] showed better corrosion resistant in the acidic solution than the willemite [Zn2SiO4].
Direct reuse of two deep-dewatered sludge cakes without a solidifying agent as landfill cover: geotechnical properties and heavy metal leaching characteristics
