Feasibility of iron-rich ore tailing as supplementary cementitious material in cement pastes

Abstract

The present work aims at evaluating the technical feasibility of reusing iron ore tailing (IOT) rich in iron in natura (sludge and dry), partially replacing cement in pastes by up to 15%. Fluid, hydration and hardened state properties were investigated. IOT favored hydration of the aluminate phases due to the nucleation effect and the rheological behavior was affected by the morphology of the particles. The early age compressive strength of the cement paste is maintained when using 10% or less of sludge in the mixture. The use of higher contents or 10% of dry IOT reduced slightly the late age strength of the material.