Pelletization of hematite and synthesized magnetite concentrate from a banded hematite quartzite ore: A comparison study

Abstract

A compressive pelletization study, for the utilization of an Indian Banded Hematite Quartzite ore, is presented in this communication. Iron ore concentrates have been generated utilizing the conventional beneficiation process and also by the approach of reduction roasting-magnetic separation. The Fe contents of the hematite and the synthesized magnetite concentrate were found to be 64.22 and 63.80%, respectively. The influence of different factors on the respective physical, chemical, and metallurgical properties of the fired pellets, generated through both the routes, have been compared. The pellets prepared from the synthesized magnetite attain the threshold Cold Crushing Strength (CCS) of 50 kg/pellet at a lower temperature of 1050 °C in comparison to hematite pellets (1100 °C). Also, the threshold CCS of 250 kg/pellet is attained by synthesized magnetite pellets at a lower temperature of 1250 °C compared to hematite pellets (1360 °C). The fired synthesized magnetite pellets also achieve the desired metallurgical properties i.e., Reduction Degradation Index (RDI), Reducibility Index (RI), and Swelling Index (SI) at par with the hematite pellets. Moreover, unlike the hematite pellets, the synthesized magnetite pellets do not need the addition of external carbon during the pellet making.