Studies on characterization of properties of low-grade hematite iron ores and their fired pellets

In this study, pellets were made from iron ores of Ramallakota and Veldurthi mines, Andhra Pradesh, by the addition of 1.5 to 4.5 wt.% of bentonite and molasses binders. Dried iron ore pellets were fired at 1173, 1373 and 1573K for 1, 2 and 3h. The aim has been to determine the effects of type of iron ore and binder, and firing conditions on the properties of resulting fired pellets. Chemical compositions and XRD patterns of studied iron ores revealed them to be of low- grade hematite iron ores having 27-46% Fe. Drop number of dried pellets got increased with an increase in their binder contents. Both the types of fired iron ore pellets exhibited an increase in their crushing strengths and decrease in apparent porosity with rise of firing temperature and time due to an increase in the extent of sintering of particles, as revealed by SEM micrographs.