Investigation on Burden Particle Softening and Melting Process under High Reduction Potential Condition

Abstract

AbstractThe present study using a single-particle softening under a load equipment was designed to better understand the softening and melting process of pellet, sinter and a mixture of both under a high reduction potential condition. Additionally, the experiment was interrupted at different shrinkage stages, and the evolvement of particle structure was analyzed. The softening and melting behavior of ferrous burden in high reduction potential compared with the general conditions was ascertained. In comparison with the general case, the thickness of the iron shell and the fineness of the metallic iron phase increased in high reduction potential. In the general condition the melting process is impacted by the low melting point of the slag with wustite outflow from the metallic iron shell, while in high reduction potential, the higher melting point of the slag without wustite exuded from the metallic iron phase. Under high reduction potential, the liquid slag was distributed in the metallic iron phase, which hindered the interaction between pellet and sinter. Thus, the temperature of interaction in high reduction potential is obviously higher than that in the general condition. The thicker iron shell and the higher melting point of slag lead to the improvement of the softening behavior under high reduction potential.