鞍山某复杂难选铁矿石预选—磁化焙烧—弱磁选试验

鞍山某复杂难选铁矿石铁含量为31.12%,主要以赤铁矿、磁铁矿形式存在,脉石矿物主要是石英。为确定预选—磁化焙烧—弱磁选工艺处理该铁矿石的可行性,进行了选矿试验研究,着重研究了焙烧温度、还原气氛CO浓度、焙烧时间和焙烧产物磨矿细度对铁精矿产品指标的影响。结果表明,在焙烧温度为560℃,CO浓度为30%,焙烧时间为10 min,焙烧产品磨矿细度为-0.038 mm占92.85%,弱磁选磁场强度为103.45 kA/m条件下,可获得铁品位为64.63%、回收率为92.01%的铁精矿。预选—磁化焙烧—弱磁选工艺是该复杂难选铁矿石的高效开发与利用工艺。

Research on Preconcentration-Magnetic Roasting-Low Intensity Magnetic Separation of Refractory Iron Ore from Anshan

There is 31. 12% of Fe in a fractory iron ore from Anshan. Valuable iron minerals of sample ore mainly exist in the form of hematite and magnetite,and primary gangue minerals are quartz. An innovative technological process consisting of preconcentration followed by magnetic roasting and low-intensity magnetic separation was applied to verify the feasibility for treating the ore. Effects of reduction temperature, concentration of carbon monoxide, reduction time and grinding fineness on concentrate index were discussed. The experiment results showed iron concentrate with Fe grade of 64. 63% and Fe recovery of 92. 01% was obtained under the conditions of reduction temperature 560℃,concentration of carbon monoxide 30% roasted for 10 min and low-intensity magnetic separation at feeding of reduction product ground to 92. 85% passing 0. 038 mm with mag-netic field intensity of 103. 45 kA/m. This technological process consisting of preconcentration followed by magnetic roasting and low-intensity magnetic separation is an innovative method to deal with the complex refractory iron ore of Anshan.