Investigation of iron ore particle size and shape on green pellet quality

Abstract

ABSTRACTParticle size and shape of iron ore concentrate are effective parameters in the production of quality green pellets. In this research, the effect of particle morphology on green pellet quality was studied. It was concluded that pellet quality improved with increasing specific surface area. Drop number and green compression strength of pellets ground by HPGR were found to be superior over those ground in the ball mill. The chief reasons were related to particle shape and the fraction of fine particles. Smaller particle size results in a higher order of bonding between particles and therefore the formation of a stronger system. Also, the rougher and less circular shape of particles resulted in higher strength. According to the breakage model in the particle-moisture system, pellet failure occurs because of crack propagation in the solid–liquid interface. The effects of roughness on capillary force and wettability have been explained mathematically. In addition, the effects of roughness and aspect ratio on breakage path and increase of required energy for pellet failure have been modelled.