Removal of Silica and Alumina as Impurities from Low-Grade Iron Ore Using Wet High-Intensity Magnetic Separation and Reverse Flotation

This study investigates the removal of silica and alumina as impurities from hematite based low-grade iron ore containing 34.18 mass% iron, 31.10 mass% of silica and 7.65 mass% alumina. Wet high-intensity magnetic separation (WHIMS) and reverse flotation (RF) were investigated. In WHIMS process, 93.08% of iron was recovered with a grade of 53.22 mass% at an optimum magnetic density of 10,000 mT, and pulp density of 2% used the L-4 machine. In RF experiments, optimal results showed 95.95% of iron recovered with 51.64 mass% grade using 1 kg/t of 1% alkaline starch as iron depressant and 1:1 mixture ratio of 0.75 kg/t DAA and NaOL as silica and alumina collectors. The designed multi-stage process involving feeding the concentrate from WHIMS into RF process reduced silica to 2.02 mass%, alumina to 1.04 mass% whilst recovering 81.94% of the iron with 67.27 mass% grade. As a result of this research, a process to produce high quality iron concentrate from hematite based low-grade iron ore with high iron recovery rate was constructed.

遵义高铁锰矿锰铁分离试验及机理研究

介绍了高铁锰矿石的性质和选矿试验结果。采用磁重浮联合流程,以强磁选抛尾,预先富集锰,磁选精矿经过多次浮选精选,可得到含锰33％,30％,25％以上3个品级的锰精矿,锰收率可达75％;磁选尾矿通过重选回收黄铁矿。文章还从菱锰矿晶体结构与可浮性,氧化石蜡皂在菱锰矿表面的作用机理,石油磺酸钠与菱锰矿作用机理,硅酸钠与菱锰矿的作用机理等的研究,说明了锰与铁的分离原理。