Effect of the separation of large limonite ore particles in the granulation process of sinter raw materials

Abstract

Sintering with large amount of limonite generally requires higher fuel consumption, either due to the dehydration of combined water or the evaporation of more added water. Although limonite can accelerate melt formation, the sintering strength indexes are in lower level on the contrary, proved to have much to do with the excessive assimilation. In order to improve the sintering behavior of sintering mix when large amount of limonite were used, a simplified method named separating large particles of limonite from granulation was investigated by measuring the bonding strength using quasi-particles on the base of confirming influence of excessive assimilation on effective liquid phase of limonite, and calculating changes in properties of sintering mix for moisture transferring. The results obtained were summarized as follows: Limonite nuclei adversely influenced bonding strength of quasi-particles mainly by the effective liquid phase, which was determined by volume decrease for penetration and viscosity increment by less fluxed melt, separation of limonite nuclei to reduce the contact interface is helpful in improving bonding of sintered body, and the separation ratio was suggested be within certain range by melt distribution in the whole bed. Less accumulation of condensed water and partial absorption by ungranulated dry limonite resulted in smaller increment in effective mean size and less decrement in void fraction, indicating better bed permeability.