Hydration study of ternary blended cements containing ferronickel slag and natural pozzolan

The present investigation focuses on the hydration evolution of ternary blended cements composed by natural pozzolan (NP) and ferronickel slag (FNS), which is produced during the pyrometallurgical treatment of laterites for the production of ferronickel. The slag and pozzolan were grounded to a specific surface area of 4000 cm2/g and twelve different cement mixtures were produced containing up to 20% Portland cement replacement with the above-mentioned cementitious materials. The produced blended cements were tested by determining their initial and final setting times, standard consistency, flow of normal mortar, soundness and compressive strength at 2, 7, 28, 56 and 90 days. X-ray diffraction and TG/DTG analyses were used for the determination of the hydration products, whereas the microstructure of the hardened cement pastes and their morphological characteristics were examined by scanning electron microscopy. According to the results, the ferronickel slag could be readily utilized together with natural pozzolan as substitutes for cement, presenting significant environmental benefits in waste management practice.