钒钛磁铁矿直接还原试验研究

在热力学分析的基础上研究了实验室条件下钒钛磁铁矿配煤直接还原的特点,考察了还原机理及还原温度、反应时间和配碳量对金属化率的影响.结果表明:采用直接还原可使钒钛磁铁矿中铁的氧化物优先还原为金属铁,钛仍以氧化物的形态存在;随着温度升高,球团金属化率呈上升趋势,且上升趋势随之减缓;在xC/xO=0.9∶1时,延长反应时间金属化率增加,但反应时间过长金属铁会被再氧化,反应时间控制在20 min为宜;在xC/xO=1.1∶1时,40 min内未出现再氧化现象;低配碳(xC/xO=0.8∶1)时,球团的金属化率随还原时间、还原温度的增加而增加,1 300℃下还原10 min后金属化率即达到了90%以上.

Experimental Study on Direction Reduction of Vanadium-Bearing Titanomagnetite

The direct reduction behavior of vanadium-bearing titanomagnetite pellets containing coal was experimentally studied in laboratory based on thermodynamic analysis. The reduction mechanism and influences of reduction temperature， reduction time，and the x_C/x_O on metallization ratio were investigated. The results showed that direct reduction iron (DRI) can be obtained in this process， while titanium exists as the form of titanium oxide in the slag. With the increase of reduction temperature， the metallization ratio increases quickly first and then slowly. For carbon-containing pellets with 0.9 of x_C/x_O， the metallization ratio reached the highest at 20min and DRI was re-oxidized after 20 min. When the x_C/x_O in the pellets was 1.1∶1， no re-oxidization happened within 40min. With less coal addition (0.8 of x_C/x_O)， there were similar phenomena with that of 1.1 of x_C/x_O and the metallization ratio was up to 90 % at 1300℃ after 10min.