1993 Volume 79 Issue 4 Pages 443-448
Direct injection of fine ores into a blast furnace has become a key technology to the development of an advanced blast furnace process for the 21st century. In order to take full advantage of this technology such as high flexibility under the coming resource circumstances, it is necessary to promote the "in-flight" reduction of fine ores in the raceway to the highest degree so as to minimize the endo-thermic reaction at the deadman due to the wustite residue.
As a base of pursuing a rapid reduction process, the study put its emphasis on revealing the microscopic reduction behavior. of fine ores. Observation showed that some of are particles which were obviously liquefied and completely spheroidizied during the experiment contained metallic irons inside the wustite shell. This particular morphology was explained by "Marangoni Effect". It was also mentioned that the "micro-flow"on the molten wustite surface had significant influence over the smelting reduction of fine ores by reducing gases.