Experimental Simulation of Ferromanganese Slag Flow in Coke Bed
摘要
The extent of feasible reduction that can occur in a submerged arc furnace is dependent on the residence time of slag in the coke bed. A quick flow will result in low reduction, while a slow flow can achieve higher reduction at the expense of production efficiency. In this study, the flow of ferromanganese slag in the coke bed has been evaluated. The slag flow is dependent on the size of voids in the coke bed, viscosity, and the interfacial tension. The primary slag will have two zones, a high-viscosity multiphase slag containing a mix of solid and liquid phases and a low-viscosity liquid slag. The low-viscosity liquid slag and the produced alloy phase will drain into the void during reduction. The multiphase slag decreases with reduction and will flow when the volume is comparable to the size of the void. Slags with lower MnO content than the liquidus composition, also called post-liquidus composition, have been studied. It is observed that the liquid slag and the alloy have low wettability and will only enter the void when the interfacial tension toward the carbon is low enough, that is a high wettability. In the presence of alloy, the wettability of low-basicity and low-MnO slag with graphite substrate varies greatly over time compared to slags with higher-basicity and MnO content. The wettability was found to be dependent on the SiO