以我国攀枝花钛铁矿为研究对象,研究钛铁矿固态碳热还原反应的宏观动力学、钛铁矿还原产物的物相转变及显微结构的变化规律,探讨攀枝花钛铁矿固态碳热还原行为。研究结果表明:钛铁矿精矿还原速率较小,在温度为1000~1150℃时,攀枝花钛铁矿精矿的还原过程受界面化学反应控制,反应的表观活化能为125.92 kJ/mol;在钛铁矿还原过程中,将会形成M3O5型(M为Fe,Ti,Mg和Mn等)固溶体和TinO2n-1等导致铁离子活度降低的物相,使钛铁矿的还原难度加大,而且还原产物的结构和Mg在未反应内核处的富集都阻碍了攀枝花钛铁矿精矿的进一步还原。
The macrodynamics of solid-state carbonthermic reduction of Panzhihua ilmenite and the mineral phases transformation and microstructure change of reduction products were researched,and the solid-state carbonthermic reduction behavior of Panzhihua ilmenite was also researched.The results show that the reduction rate of ilmenite is low,and the reduction reaction is controlled by interfacial chemical reaction and apparent activated energy of reaction is 125.92 kJ/mol at 1 000-1 150 ℃.The M3O5(M is Fe,Ti,Mg,Mn,etc) solid solution and TinO2n-1 are found during the reduction processes,in which the activity of iron ion decreases and the reduction difficulty increases.Besides,the structure of reduction products and enrichment of Mg in the unreacted core restrict the further reduction of ilmenite.