This paper presents a study of the potential use of iron mining tailings as artificial pozzolan (metakaolin) after their submission to thermal treatment via calcination in a flash furnace. The research consists of the characterization of the tailings before and after calcination, chemical, mineralogical, thermogravimetric, and mechanical strength analyses were conducted. The results were compared with those for commonly used pozzolans, metakaolin, and similarities were identified. The study of the morphology of the particles before and after calcination was conducted through analyses of images obtained by scanning electronic microscope. The pozzolanic activity of the fine mining tailings calcined with flash technology was evaluated in uniaxial compression trials, which showed excellent results.
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