硫酸渣磁化焙烧-磁选提铁降硫

Iron concentration and sulfur reduction on sulphuric acid drag by magnetic roasting-magnetic separation

硫酸渣铁品位为55.08%,其中有害元素硫的含量为1.3%.为高效利用硫酸渣,必须提高铁含量、降低硫磷等有害元素.硫酸渣试样直接进行弱磁选,得到铁精矿品位60.54%,精矿回收率仅为54.46%,采用磁化焙烧-弱磁选的方法来进行选铁试验,通过对磁化焙烧时间、磁化焙烧温度、还原剂的质量配比等条件试验,确定了在焙烧时间40min,焙烧温度750℃,还原剂10%的最佳焙烧条件.焙烧矿磨矿至-0.074mm97.02%,用弱磁选管进行磁选的最佳试验条件,在此焙烧条件下,进行一粗一精的磁选,获得了铁品位64.57%,精矿回收率86.99%,硫含量降低到0.13%.

The iron content （mass fraction） is 55.08% and the sulfur is 1.3% in sulfuric acid residue. This experiment aims at improving the iron grade and reducing the harmful elements such as sulfur in the drag. Direct magnetic separation was used, obtaining 60.54% iron concentrate grade, only 54.46% iron recoveries. Then process of magnetizing roasting-magnetic separation was put forward. Through analyzing the experimental condition of magnetizing roast temperature, magnetizing roast time and the proportion of reducer, the condition of 40 minutes of roast time, 750 ℃ of roasting temperature and 10% reducer is the best. When the roasted product is grinded to --0. 074 mm 97.02%, a good index through simple mineral processing is got, the iron grade of concentrate reaches to 64.57% % and the iron recovery rate reaches to 86. 99G. The mass fraction of sulfur in iron concentrate is reduced to 0.13% after the roasting product is separated by one roughing and one cleaning magnetic separation process.