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