The fundamental objective of this study was to define such a cement composite with the addition of
white (ladle) slag, which will provide functionality for selected purposes and furthermore, prevent the
leaching of toxic elements into the environment. The recovery (recycling) of secondary metallurgical
slags from stainless steel production has an important synergistic impact on the environment. In this
study, detailed characterization of slag derived from two different ladle refining processes of stainless
steel production has been performed. In order to assess its potential for use as a supplementary
cementitious material, slag cement composites as well as slag itself were investigated. A comparative
study of reference cement composites and cement composites to which a conventional supplementary
cementitious material (limestone filler) had been added, was also performed. The results showed that
the slag contains hydraulic phases to a total amount of about 50 %. Calcium aluminates are the
predominant constituents. In the case of slag cement composites, a larger degree of strength
development was observed in comparison to the cement composite with the addition of limestone
filler. This was attributed to the larger proportion of hydration products formed in the slag cement
composite. The environmental impact of cement composite with the addition of the investigated slag
was further evaluated. The results revealed that chromium was immobilized in the cement composites
with the addition of slag. Cr(VI) content originating from the cement was also appreciably reduced by
the added slag, which thus had significant positive environmental effects. The stabilization process is
controlled by the reducing and hydraulic properties of the slag. It was demonstrated that the presence
of the investigated slag in cement composites does not influence its durability. The investigated white
(ladle) slag can be implemented in cement composites as supplementary cementitious material.
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