Iron Ore Concentrate Particle Size Controlling Through Application of Microwave at the HPGR Feed
Nowadays, the HPGR (high-pressure grinding rolls) is an intermediate step between filtering and balling in the most modern iron ore pelletizing operation. The operation debottlenecks filtering process and reduces pressure over the typical milling process to control particle size to the balling. The present study evaluated aspects of microwave application to the iron ore concentrate fed to HPGR in a bench scale unit. Iron ore concentrate was irradiated varying the microwave exposure time and grinding efficiency was evaluated. The moisture influence in the HPGR efficiency was also assessed. The pellet feed blaine surface area (BSA) improved by 300 cm2/g and % < 325# fraction by 3%. Scanning electron microscope (SEM) images show the formation of micro-cracks onto the particle surface induced by microwave; the effect observed helped improve the milling process performance, in addition to the moisture reduction observed due to the temperature increase.
KeywordsHPGR Microwave Moisture Pelletizing
The authors would like to thank Samarco Mining, CAPES-PROEX, CNPq, and FAPEMIG for stimulating and supporting research.
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
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