东鞍山某鲕状赤铁矿石悬浮焙烧试验

Suspension Calcination of Oolitic Hematite Ore from Donganshan

东鞍山某鲕状赤铁矿石铁品位为44.53%、P2O5含量为2.25%。矿石中赤铁矿主要以鲕状集合体形式存在,嵌布粒度微细,属难选矿石,采用传统选矿工艺难以获得理想的选别指标。为给该矿石合理开发利用提供依据,进行了悬浮焙烧—磁选试验。结果表明:在给矿细度为-0.074 mm占75%、总气流量为8 m^3/h、H2浓度为40%、焙烧温度为650℃、焙烧时间为75 s条件下进行悬浮焙烧,焙烧产品磨细至-0.074 mm占95%,在磁场强度为85.1k A/m条件下磁选,获得了铁品位为56.73%、回收率为83.96%、磷含量为0.78%的铁精矿,该精矿磷含量较高,还需进一步进行降磷研究。试验结果为我国鲕状赤铁矿石的开发利用提供了参考。

There is 44. 53% iron,and 2. 25% phosphorus pentoxide in an oolitic hematite ore from Donganshan. Hematite mainly finely disseminated in form of oolitic aggregates,belongs to refractory iron ore. It＇s difficult to obtain ideal separation index via traditional concentration process. In order to provide technique basis for reasonable development and utilization of the ore,suspension roasting-magnetic separation experiments was conducted. The results indicated that： at the grinding fineness of75%- 0. 074 mm for raw ore,total gas flow rate of 8 m^3/ h,hydrogen concentration of 40%,suspension roasting temperature of650 ℃ for 75 s,roasting products ground to 95% passing 0. 074 mm,then via magnetic separation at magnetic field intensity of85. 1 k A/m,iron concentrate with 56. 73% iron,0. 78% phosphorus,and iron recovery of 83. 96% was obtained. The content of phosphorus in concentrate was a bit high,further study should be conducted. The results provide technique basis for development and utilization of oolitic hematite ore.