Experimental analysis of the melt fraction - mechanical strength relationship for iron ore sinter analogues

Abstract

This study examined the strength of sinter analogue tablets for different types of iron ore under varying sintering conditions. A steel tamper was designed to quantify strength based on the percentage of 1 mm retained size after a drop weight test. The study found a linear relationship between total melt fraction M and strength index S quantified by mass fraction of the +1 mm retained size: S=0.88M. Importantly, a relationship was found between the total melt and a combined F factor incorporating the thermodynamic liquid fraction (α, representing sintering conditions) and the mineralogical factor loss on ignition (LOI ratio, β, representing ore types), where F=6.5α+β−1. This factor F was found well correlated the total melt via an asymptotic exponential relationship as M=1−2.6e−F. The results also suggested that, to achieve an acceptable strength of 80% +1 mm for a typical basicity B = 2, a sintering temperature range between 1273 and 1370 °C is required for the LOI range between 1.6% to 10.7% respectively. Finally, an analogous analysis was also carried out which proposed a similar trend between sinter yield obtained in a kilogram-scale by lab-scale studies and the present 0.6-g analogue scale.