超级铁精矿深度提纯试验研究

Experimental Study on Deep Purification of Super Iron Concentrate

为探索化学法获取超纯铁精矿的可能性,以国内某铁矿选厂的超级铁精矿为原料,分别以硫酸—氟化钠和硫酸—氢氧化钠为浸出剂开展提纯试验。结果表明:①经过硫酸—氟化钠联合处理,在硫酸浓度10%、矿浆浓度15%、氟化钠用量14 g/L,30℃恒温反应1 h的条件下,可以得到铁品位为72.12%、铁回收率为94.23%的超纯铁精矿。②经过硫酸—氢氧化钠联合处理,在一阶段硫酸浓度10%、矿浆浓度15%、30℃恒温反应1 h,二阶段氢氧化钠用量160 g/L、液固比6 mL/g、80℃恒温反应2 h的条件下,可以得到铁品位为72.14%、铁回收率为99.67%的超纯铁精矿。硫酸—氟化钠联合处理法比硫酸—氢氧化钠联合处理法简洁,但铁回收率较低,含氟废水需处理后才能排放;硫酸—氢氧化钠联合处理法铁回收率较高,生产成本也较高。与常规选矿工艺提升铁品位的方式相比,化学处理法能更深度地纯化铁精矿。

In order to explore the possibility of obtaining ultra-pure iron concentrate by chemical method,the super iron concentrate from a domestic iron ore sorting plant was used as raw material,and the purification experiment was carried out with sulfuric acid-sodium fluoride and sulfuric acid-sodium hydroxide as leaching agents,respectly.The results showed that:①After the combined treatment of sulfuric acid and sodium fluoride,under the suitable conditions of sulfuric acid concentration of 10%,pulp concentration of 15%,sodium fluoride of 14 g/L,and constant temperature of 30℃for 1 h,ultra-pure iron concentrate with iron grade of 72.12%and iron recovery rate of 94.23%could be obtained.②After the combined treatment of sulfuric acid and sodium hydroxide,under the conditions of sulfuric acid concentration of 10%,pulp concentration of 15%,constant temperature of 30℃for 1 h in the first stage,sodium hydroxide dosage of 160 g/L,liquid-solid ratio of 6 mL/g,and constant temperature of 80℃for 2 h in the second stage,ultra-pure iron concentrate with iron grade of 72.14%and iron recovery rate of 99.67%could be obtained.The sulfuric acid-sodium fluoride combined treatment method is simpler than the sulfuric acid-sodium hydroxide combined treatment method,but the iron recovery rate is low,and the fluorine-containing wastewater needs to be treated before discharge.The iron recovery rate of sulfuric acid-sodium hydroxide combined treatment is high,and the production cost is also high.Compared with the conventional beneficiation process to improve the iron grade,the chemical treatment method can purify the iron concentrate more deeply.