Melting Behavior and Interaction of Gangue Phase of Iron-containing Burden

Abstract

The cohesive zone is an important location in the blast furnace due to decrease of permeability and sharp increase of pressure drop. Since the liquid phase has an important influence on the permeability, this study aimed to investigate the regulation of liquid phase formation in the cohesive zone. Through melting experiments of single and double slag tablets combined with thermodynamic calculations, some important phenomena were observed. The pellet slag melted prior to sinter slag, and the molten pellet slag caused the sinter slag to melt at a temperature below the melting temperature. The liquid phase of the cohesive zone originated due to the low melting point material of the gangue phase, and the interaction of different iron-containing burdens gangue phase. The production of the liquid phase was affected by the composition and temperature. The progress of the interaction seemed to be affected by the liquid phase ratio. The interaction was re-understood: interaction is physicochemical reactions of gangue phases of different iron-containing burdens which occurred during the formation of molten blast furnace slag with uniform composition. Thermodynamic calculations were consistent with the experimental results and showed that the interaction of the cohesive zone increased the liquid phase, which was disadvantageous for the permeability.