Na_2CO_3促进复杂难选铁矿石深度还原的机理分析

Mechanism Analysis on Deep Reduction of Complex Refractory Iron Ore Promoted by Na_2CO_3

以羚羊铁矿石为原料,在1 200℃下深度还原40 min,通过外配Na2CO3的方法研究了Na2CO3对羚羊铁矿石深度还原的影响,并从热力学角度探讨了Na2CO3促进深度还原的机理.结果表明,铁橄榄石(2FeO.SiO2)、铁尖晶石(FeO.Al2O3)等复杂化合物的生成是影响还原物料金属化率和铁粉品位的一个重要因素.配入的Na2CO3分解产生的Na2O可以置换铁复杂化合物中的FeO;同时和矿石中的SiO2和Al2O3反应,进而有效减少了与FeO反应的SiO2和Al2O3的量,从而提高了还原物料的金属化率及铁粉品位.

Effect of Na2CO3 on deep reduction of antelope iron was studied under the temperature of 1 200 ℃ and duration of 40 min. Characteristics of solid-state in deep reduction was analyzed by thermodynamic analysis. Complex iron compound such as fayalite and hercynite that was generated during deep reduction is one of the primary factors that affect metallization rate and the index of iron powder. According to analysis, FeO is replaced from complex iron compound by Na2O, which is decomposed from Na2CO3. At the same time, because of reactions between SiO2, and Al2O3, the amount of SiO2 and Al2O3 that may react with FeO is effectively reduced, thus improving the metallization rate and the index of iron powder.