镜铁矿粉矿制粒回转窑磁化焙烧及分选研究

甘肃酒泉地区镜铁矿是一种难选贫铁矿石,回转窑磁化焙烧是处理此类矿石的有效方法,但粉矿需磨细造球,工艺复杂。为利用该粉矿,试验结合其细粒级含量高的特点,采用制粒—回转窑磁化焙烧—磁选工艺。结果表明,粉矿在膨润土质量配比1%、水分8%条件下制粒成3~8 mm小球,在焙烧温度750℃、焙烧时间60 min、兰炭质量配比2.5%、填充率20%的条件下经回转窑磁化焙烧,焙烧矿磨至-0.074 mm占85%,采用一粗一扫一精的磁选流程,获得精矿品位56.16%、回收率85.24%的良好指标,为此类粉矿的高效利用提供了借鉴。

Study on Granulation Magnetic Roasting with Rotary Kiln and Separation of Fine Specularite

The lean specularite from Jiuquan in Gansu is difficult to be separated .Magnetic roast-ing with rotary kiln is an effective way to process this type of ore , in which fine specularite need to be ground and pelleted .In order to utilize fine specularite , granulation-rotary kiln magnetic roast-ing-magnetic separation process based on its properties was adopted .Small pellets with a diameter of 3~8 mm were prepared with 1%bentonite and 8%water.Then the pellets were roasted at 750℃for 60 min, during which the dosage of carbon was 2.5% and the filling rate was 20%.The roasted ore, ground to -0.074 mm which accounted for 85%, was couducted with a magnetic sep-aration process of one roughing , one scavenging , one screening and one concentration .Finally, i-ron concentrate with grade of 56 .16%and recovery of 85 .24%was obtained .This study provided some reference for utilization of fine specularite .