研究一种处理磁选前高铝硅氰化渣的新工艺。采用复合添加剂焙烧-水浸-磁选工艺对一种铁品位为27.69%(质量分数),SiO2含量为23.9%,Al2O3含量为6.35%的高铝硅氰化渣进行杂质与铁分离的研究。研究结果表明:在最佳焙烧条件下,当水浸温度为60℃,液固比为15:1,水浸时间为5 min,转速为20 r/min,在激磁电流为2 A时,可获得铁品位57.11%,铁的回收率为72.58%的铁精矿。铁的品位和回收率都比单纯的复合添加剂还原焙烧-磁选法所获得的铁精矿的指标高,铁的品位提高了10%左右,回收率提高了30%左右。X线荧光(XRF),X线衍射(XRD)及能谱(EDS)分析研究结果表明:经水浸后,复合添加剂焙烧过程中所产生的可溶性复杂杂质化合物被洗除,不溶性物质经磁选后随之进入非磁性物,实现铁与杂质矿物之间的有效分离。
A novel process was developed to treat the high-aluminum and silicon cyanide tailings before magnetic separation.Fe-impurities separation from a high-aluminum and silicon cyanide tailings with total iron grade of 27.69%(mass fraction),SiO2 content of 23.9% and Al2O3 content of 6.35% was studied in the process of compound additives roasting-water leaching-magnetic separation.The results show that under the best roasting condition,magnetic concentrate with total iron grade of 57.11% and the recovery rate of 72.58% are obtained when the leaching temperature is 60 ℃,the liquid-solid ratio is 15:1,the leaching time is 5 min,the stirring speed is 20 r/min and the exciting current is 2 A.The grade of magnetic concentrate and recovery rate of iron are higher than the indexes obtained by the method of simple additive reduction roasting-magnetic separation.The grade of magnetic concentrate increases by about 10% and the recovery rate of iron raises by about 30%.The X-ray fluorescence(XRF),X-ray diffraction(XRD) and energy dispersive spectrometer(EDS) results indicate that the soluble impurities generated in the compound additives roasting process are washed out,and the dissoluble substances enter into nonmagnetic materials by water leaching,thus realizing the effective separation of impurities and Fe.