【摘要】 以活性炭为还原剂,氩气为保护气,采用微波还原焙烧的方法,将3种低品位赤铁矿还原为磁铁矿,并研究了微波还原焙烧温度、碳含量、保温时间及微波输出功率对其磁选指标的影响规律。结果发现:相同质量3种赤铁矿进行微波还原焙烧,随配碳量的增加,其升温速率加快,且3种赤铁矿具有相似的微波还原焙烧规律,即:在570~650℃、理论配碳量、微波输出电压220 V及保温10 min的条件下,其还原产物弱磁选后的品位和回收率均达到最佳,且磁铁精矿经细磨-二次磁选后,铁品位均能提高到60%以上。该研究对开发低品位赤铁矿的选冶技术新流程有重要的指导意义。更多还原

【Abstract】 Three kinds of low grade hematite were changed into magnetite by microwave reduction roasting process with argon as protective gas and active carbon as reductant. The influences of roasting temperature,carbon content,holding time and microwave output power on magnetic separation results were investigated. It was showed that heating rates of three kinds of hematite ores of same mass increased with the increase of C content during microwave heating. There was a similar microwave reduction roasting law for three kinds of hematite,that is,the grade and recovery of the sinters after low intensity magnetic separation were optimum at a roasting temperature of 570 ~ 650 ℃,with theoretical carbon content,holding time of 10 mins and microwave output voltage of 220 V. Furthermore,the iron grades of three kinds of magnetic concentrates all reached up to 60% after the process of fine grinding-secondary magnetic separation. This work has great instructive significance for the development of new dressing and metallurgical processes for low grade hematite.更多还原