水洗脱酸对酸浸脱磷人工磁铁精矿表面性质及球团性能的影响

Effect of water-washing deacidification on surface and pellet properties of artificial magnetite concentrate after acid leaching dephosphorization

我国铁矿石通常经选矿后进行造块制备优质炉料,部分复杂铁矿需经酸浸或其它化学选矿才能产出高品质的铁精矿,该类型铁精矿由于表面亲水性弱而导致生球性能差。为了充分利用此部分矿种,本文采取水洗脱酸预处理酸浸脱磷磁铁精矿,考察水洗对铁精矿表面性质与球团性能的影响,为酸浸脱磷精矿球团制备提供理论依据和强化措施。研究结果表明:水洗脱酸预处理可使酸浸脱磷铁精矿细颗粒增加,比表面积从1 682 cm~2/g增加到1 853 cm~2/g,接触角从33.77°降低到31.82°,亲水性增强,颗粒的物理稳定性提高。经水洗脱酸,酸浸脱磷铁精矿生球强度与焙烧性能得到改善,落下强度由1.0次/(0.5 m)升高到5.8次/(0.5 m),焙烧球强度从999 N/P提高到2 500 N/P以上。

Iron ore is usually agglomerated after beneficiation to obtain the high-quality charge in China.Some complex iron ores need acid leaching or other chemical beneficiation to produce high-quality iron concentrate, this type of iron concentrate has the poor performance of green balls due to its weak surface hydrophilicity.To fully optimize this kind of miderals, in this paper, the magnetite concentrate after acid leaching dephosphorization is pretreated by water-washing deacidification, and the effect of water washing on the surface and pellet properties of iron concentrate is investigated in order to provide the theoretical basis and strengthening measures for pellet preparation of acid leaching dephosphorization concentrate.The results show that water-washing deacidification pretreatment can increase the ratio of the fine particles, and the surface area increased from 1 682 cm~2/g to 1 853 cm~2/g.The contact angle decreased from 33.77° to 31.82°,enhancing hydrophilicity and improving particles’ physical stability.After water-washing deacidification, the strength of green balls and roasting performance of acid-leaching dephosphorized iron concentrate are improved.The drop strength increased from 1.0 times/(0.5 m)to 5.8 times/(0.5 m),and the compressive strength of fired pellets increased from 999 N/P to more than 2 500 N/P.