针对传统磁化焙烧装备及技术所存在的还原时间长、还原不均匀、能耗及生产成本高等问题，采用悬浮焙烧法处理湖北某鲕状赤铁矿石。结果表明，在给矿细度为-0.074 mm占80%、气体速度为1.4 m/s、H2浓度为40%、还原温度为650℃、焙烧时间为10 s 条件下，对铁品位为46.31%的鲕状赤铁矿石进行悬浮焙烧，焙烧产品磨细至-0.035 mm占90%后，在磁场强度为85 kA/m条件下磁选，可获得铁品位为58.32%、回收率为85.69%的铁精矿。对焙烧产品进行XRD分析表明，矿石中的赤铁矿经悬浮焙烧后转变为磁铁矿。对悬浮焙烧产品进行磁性分析表明，鲕状赤铁矿中弱磁性铁矿物经悬浮焙烧可快速转变为强磁性铁矿物，焙烧后物料的磁化强度和比磁化率显著提高。悬浮焙烧具有焙烧时间短、热利用效率高、处理能力大等优点，可在较短的时间内实现铁矿石的磁性转变，为难选铁矿石的利用开辟了新的途径。%Suspension roasting for an oolitic hematite from Hubei province was carried out to solve the long reduction time,uneven reducing,high energy consumption and high production costs of traditional magnetic roasting equipments and tech-nology. The results show that an iron concentrate with iron grade of 58. 32% and recovery of 85. 69% can obtained under the conditions of material size of 80% passing 0. 074 mm,gas velocity of 1. 4 m/s,H2 concentration of 40%,reduction temperature of 650 ℃ for 10 s,magnetic separation was brought after ground the roasted products at 90% passing 0. 035 mm . The XRD a-nalysis of roasted material show that hematite in ore can transformed to magnetite via suspension roasting. The magnetic analy-sis show that weakly magnetic iron mineral in oolitic hematite ore can rapidly transformed to magnetite during suspension roast-ing. The magnetization and magnetic susceptibility of reduced material were greatly increased. Suspension roasting has advanta-ges of short roasting time,high heat utilization efficiency and large processing capacity,can transform the magnetic property of iron ore in a short time and provide a new approach for utilizing refractory iron ores.
展开▼
