The Effects of Volatile Materials of Non-coking Coal on the Reduction of Hematite

One of the most important methods to produce sponge iron is coal based reduction of iron ore. Direct reduction methods based on coal are being improved due to the abundance of coal sources and its lower cost in comparison with natural gas. Volatile materials in coal play an important role in the reduction of iron oxides. In this study, noncoking coal with high volatile materials from Iran and commercial hematite with the purity of 98% were used to investigate the effect of volatile materials on the reduction process. The effects of reduction time (0 to 75 minutes), temperature of reduction (700 to 1000 oC), particle size of coal (53 to 250 micron), and the ratio of carbon content of coal to hematite (0.9 to 1.2) were investigated. The results indicated that volatile materials could reduce 56% of iron oxide. The XRD results of reduced materials implied the stepwise reduction process. Furthermore, activation energy was increased with increasing the degree of reduction.