Application of calcareous iron ore tailings in the production of cement

In order to effectively manage large quantities of discharged iron ore tailings (IOTs), this investigation studied the application of calcareous IOTs in cement production with the analysis of clinker phases and hydration products using X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. Furthermore, the influence of the addition of calcareous IOTs on the physical strengths of the prepared cement was evaluated. The results showed that the clinker phases were C3S, C2S, C3A, and C4AF, and the cement hydration products were claviform ettringite, granular C-S-H gels, and flaky Ca(OH)2. In addition, the maximum amount of IOTs added for a 52.5 grade cement production was 6 wt.%. This investigation is beneficial in both reducing the use of conventional cement materials and the management of IOTs.