This study investigates the microwave carbothermal reduction of low-grade banded hematite jasper iron ore (Fe ~ 37%). The susceptibility of iron phases to microwave exposure and their selective absorptions help in the liberation of iron values from impurities. It was found that a small fraction of the microwave-irradiated ore-charcoal mixture was rapidly melted to produce pure ferrite balls with Fe ~ 90%. The ferrite balls were observed within 6-10 min of reduction at 8% and above charcoal at microwave power of 900 W. The iron grade deteriorated over prolonged exposure because of the formation of the fayalite phase. The optical micrograph of the ferrite ball reveals retained austenite and martensitic iron phases with an average hardness value ~ 302 HV and a saturation magnetization of ~ 190.4 emu/g.

中文翻译：

---

带状赤铁矿碧玉矿石的微波辅助碳热还原

本研究研究了低品位带状赤铁矿碧玉铁矿石（Fe〜37％）的微波碳热还原。铁相对微波辐射的敏感性及其选择性吸收有助于从杂质中释放铁值。发现一小部分受微波辐照的矿石-木炭混合物迅速熔化，以生产出Fe〜90％的纯铁氧体球。在900 W的微波功率下，在8％或以上的木炭还原后的6-10分钟内观察到铁氧体球。由于形成了铁橄榄石相，铁的等级随着长时间的暴露而劣化。铁氧体球的光学显微照片显示残留奥氏体和马氏体铁相，平均硬度值为〜302 HV，饱和磁化强度为〜190.4 emu / g。