攀枝花钛精矿真空碳热固相还原
Vacuum carbothermal solid phase reduction of Panzhihua ilmenite concentrate

运用FactSage、XRD和BSE-EDS分析手段研究了在1 000~1 400℃下真空碳热还原钛精矿的物相变化及还原历程。结果表明：还原温度能促进还原反应进行和金属铁的形核长大。当温度为1 200~1 300℃时反应最为剧烈；在1 350℃时有硅进入铁相，初期有少量的Fe2TiO4→FeTiO3，钛精矿的还原历程主要为：FeTiO3→FeTi2O5→Ti3O5→Ti2O3。铁氧化物被还原为金属铁，并形核集聚长大，钛氧化物则由高价态向低价态转变，还原最终主要物相为Ti2O3和金属铁。还原过程中会形成（Fe，Mg） TiO3及M3O5型固溶体，遏制铁的还原效果。
The phase transformation and reduction process of vacuum carbothermal reduction ilmenite concentrate at the temperature from 1 000℃ to 1 400℃ were studied by using FactSage, XRD and BSE-EDS. The results showed that reduction temperature promoted the reduction reaction and the nucleation and growth of the metallic iron. The reaction was most intense at the temperature from 1 200℃ to 1 300℃. At 1 350℃, silicon entered the iron phase region. Except for a small amount of Fe2TiO4→FeTiO3 at the initial stage, the reduction process of ilmenite concentrate was basically carried out along the FeTiO3→FeTi2O5→Ti3O5→Ti2O3. Iron oxides were reduced to metallic iron and aggregated and grown, while titanium oxides changed from high valence to low valence. Finally, the main phases of the reduction were Ti2O3 and metallic iron. A solid solution of (Fe, Mg)TiO3 and M3O5 was formed during the reduction process, which restrained the reduction effect of iron