Effect of NaOH on Direct Reduction of Vanadium Titano-magnetite

In order to reduce the direct reduction temperatures of vanadium titano-magnetite and improve the metallization ratio of pellets,sodium-treatment was adopted to the direct reduction of vanadium titano-magnetite.The vanadium titano-magnetite was direct reduced with coal and NaOH,and the influences of C/O,temperature,time,Na/Si on direct reduction were studied,the chemical analysis and XRD were used to measure metallized pellets as well.The results show that NaOH can reduce the direct reduction temperature and improve the reducibility performance of vanadium titano-magnetite significantly.The metallization ratio of pellets reduced at 1 150 ℃ for 50 min without NaOH is only 79.87%;the metallization ratio of pellets reduced can reach 93.17% at 1 150 ℃ for 30 min with Na/Si=5.0.XRD analysis indicates that titanium,aluminum and silicon oxides have been changed into the sodium salt respectively in the metallized pellet.The addition of NaOH is favorable for the reduction of iron bearing minerals,and the energy consumption can be greatly reduced.