关键词: 鲕状赤铁矿, 焙烧, 磁选, 酸浸, 提铁脱磷

Abstract: The process of roasting-magnetic separation and acid leaching was adopted to deal with oolitic hematite ore in Hezhang, Guizhou, and the influence of the roasting-magnetic and acid leaching element on iron increase and phosphorous reduction was investigated. The results show that roasting temperature and grinding fineness have an obvious effect on iron increase and phosphorous reduction. With the roasting temperature increasing, iron grade and recovery were all first increasing and then decreasing, while phosphorus content was first decreasing and then increasing. With grinding fineness increasing, iron grade was first decreasing and then increasing, while iron recovery was first increasing and then decreasing and phosphorus content was reducing gradually. Using acid leaching would reduce the phosphorus content to 0.20% below in the roasting - magnetic concentrate. When the ore was roasted for 40 min with 5.00% coal powder amount at the temperature of 800 ℃, after first grinding then adopting a flow-sheet consisting of one-roughing and one-cleaning magnetic separation, an iron concentrate grading 59.21% at a recovery of 70.32% with phosphorus content of 0.43% was obtained. When acid leaching for magnetic separation concentrate was adopted, an iron concentrate grading 60.43% with phosphorus content of 0.18% was obtained.

Key words: hematite, Roasting, Magnetic separation, Acid leaching, Iron increase and Phosphorous reduction