Blast furnace slag obtained from dry granulation method as a component in slag cement

Blast furnace slag obtained from water quenching is generally used for cement production. However, harmful waste, such as SO2, H2S and heavy metals, is discharged into the surrounding environment after water quenching. Dry granulation is an environmentally-friendly treatment, and the performance of dry granulation slag cement is investigated in the study. The results demonstrated that the particle size distribution and XRD pattern of dry granulation slag were similar to those of slag obtained from water quenching. The early strength of cement mortar made from dry granulation slag was very low, less than 50% of the cement clinker strength. Due to the weak reaction with the slag, the content of the CH phase was high. Next the CH phase was consumed in a reaction with dry granulation slag after 28 days. Crystalline and amorphous CSH were formed in the hydration of the slag cement paste system from dry granulation, and were measured by XRD and FTIR. The compressive strength data, including SEM study, indicate that dry granulation slag can accelerate the hydration of slag cement in the next stage.