焙烧温度及时间对白云鄂博铁矿选铁尾矿悬浮磁化焙烧的影响

为了回收白云鄂博铁矿选铁尾矿中的铁矿物，采用强磁预富集-悬浮磁化焙烧-磁选工艺进行铁矿物再选试验。结果表明：TFe品位为14.10%的白云鄂博铁矿选铁尾矿经磁选预富集所得精矿在总气量600 mL/min、CO浓度15%、焙烧温度800 ℃、焙烧时间5 min条件下焙烧后，焙烧产品磨细至d90=39.29 μm，在磁选管磁场强度为10.56 kA/m时，可获得TFe品位为63.88%、对原矿回收率为57.25%的磁选精矿。对试验各阶段产品分析表明，焙烧温度过高、焙烧时间过长会导致过还原，同时焙烧过程使得预富集精矿中表面光滑无裂纹的赤铁矿变为表面伴有微裂纹的磁铁矿。研究结果为多金属共（伴）生铁矿资源的高效利用提供了理论基础。

Effect of Calcination Temperature and Time on Suspension Magnetization Roasting of Iron ailings in Bayan Obo Iron Ore

In order to recover iron ore from the tailings of Baiyun Obo Iron Mine， the high intensity magnetic separation preconcentration-suspension roasting-magnetic separation process was used to carry out the iron ore re-concentration test. The results show that the preconcentrated concentrate from tailings of Baiyun Obo Iron Mine with TFe grade of 14.10%， via the total gas volume of preconcentrated concentrate is 600 mL/min， in which the CO concentration is 15%， the roasting temperature is 800 ℃， and the roasting time is 5 min. After roasting， the particle size of the roasted product is d90=39.29 μm， and the magnetic field strength of the magnetic tube is 13.2 mT， the magnetic separation concentrate with TFe grade of 63.88% and total iron recovery of 57.25% can be obtained. The product analysis of each stage in the test shows that too high roasting temperature and too long roasting time will lead to excessive reduction. Meanwhile， the roasting process makes the hematite without cracks in the surface of preconcentrated concentrate change into magnetite with micro-cracks on the surface. The study can provide technical basis for the development and utilization of polymetallic co-associated iron ore resources.