Investigation on Loss on Ignition to Study the Effect of Iron Ore Mineralogy in Green Pellet Growth Kinetics

Abstract

This study corroborates that the iron ore mineralogy has significant effects on green pellet growth and its properties by both experimental and mathematical arguments. In this context, three iron ore samples with different loss on ignition (LOI): 2.64, 4.85 and 9.19 wt.% were taken. The mineralogical differences were investigated through X-ray diffraction, thermogravimetric analysis, and heating cycle studies. The pellet properties; green compressive strength, drop, and moisture were evaluated for 8-16 mm green pellets. An empirical correlation was developed to predict the average green pellet size (D-Avg.) in correlation with disc rpm (R-D), inclination (I-D), retention time (T), LOI (L), and feed size (d(50)) of the ore with root-mean-square deviation of 0.290. The effect of mineralogy was quantified by modifying the existing self-preserving size distribution model using D-Avg. and the operating variables with R-2 of 0.941. The comparison between observed and predicted D-Avg was found with R-2 of 0.985.