预氧化在攀枝花钛铁矿固态还原过程中的作用

Effect of pre-oxidation on Panzhihua ilmenite in solid state reduction process

研究了预氧化对攀枝花钛铁矿还原行为的影响.结果表明:预氧化加快了钛铁矿铁氧化物的还原速率,提高了还原产物铁的金属化率.其作用机理是:钛铁矿在预氧化过程中形成了假金红石、三氧化二铁、金红石和三价铁板钛矿等新的物相,破坏了原有矿物结构,颗粒内部形成了大量孔隙,有利于增大颗粒的比表面积,改善还原过程气体的扩散条件;经预氧化处理的钛铁矿在预氧化过程中形成的新物相将被重新还原,新生钛铁矿活性高,还原产物的显微结构也得到了进一步的改善.

The effect of pre-oxidation on the reduction behavior of Panzhihua ilmenite was studied.The results show that pre-oxidation can speed up the reduction rate of ilmenite iron oxide and improve the iron metallization rate of reduction products.The action mechanism is that new phases of shame rutile,ferric oxide,rutile,and trivalent pseudobrookite formed in the pre-oxidation process of ilmenite,which destroyed the structure of original minerals and formed plenty of pores in the granule interior.It would be beneficial to enlarge the specific surface area of the granule and improve the gas diffusion in reduction process.Also after pretreatment of oxidation,new phases formed in pre-oxidation process would be re-reduced,neonatal ilmenite has high activity,and the microstructure of reduction products is improved.