关键词: 浮选铁尾矿, 预富集, 磁化焙烧, 磁选

Abstract: The iron grade of tailings from Donganshan Sintering Plant is 17.20%， mainly exists in hematite or limonite with a distribution rate of 70.17%， and the amount of magnetite is small. In order to provide a basis for the efficient recovery and utilizing the flotation tailings efficiently， a systematic experimental study was carried out using the process of pre-concentration followed by magnetization roasting and magnetic separation. XRD and iron phase analysis were performed on the iron ore before and after the magnetization roasting. The results showed that the pre-concentration concentrate obtained by magnetic separation was roasted under the conditions of roasting temperature of 560 ℃， roasting time of 12 min， total gas volume of 0.03 m3/h， CO concentration of 30%. Then， the roasted product was ground to bellow 0.025 mm accounting for 98%. The concentrate with iron contents of 63.02%， recovery of 81.39% was finally obtained by magnetic separation with a magnetic field strength of 104 kA/m. Through magnetization roasting， the distribution rate of hematite or limonite in the roasted product was reduced from 66.98% to 2.85%， and the distribution rate of magnetite was increased from 13.98% to 88.36%， which indicated that magnetization roasting can efficiently transform weakly magnetic iron ore into strong magnetic iron ore.The iron in the roasted production could be recovered efficiently with the magnetic separation.

Key words: flotation iron tailings, pre-concentration, magnetization roasting, magnetic separation