Effect of degree of burden mixing on the permeability of ferrous burden layers in the cohesive zone

Abstract

The cohesive zone is the location where the pressure drop is the largest within the blast furnace. Researchers usually adopt the way of increasing the permeability of the softening-melting ore layer to achieve the purpose of improving the permeability of the cohesive zone. In this study, we proposed the concept of the degree of burden mixing (DBM). Through experiments and thermodynamic calculations found that the increase in DBM enhanced the interaction between sinter and pellet, made the burden produce a liquid phase in the cohesive zone, and deteriorated permeability. In addition, the amount of liquid phase in the cohesive zone determined the permeability of the cohesive zone. Therefore, suppressing the interaction between burdens can be considered as one of the effective ways to improve the permeability of the cohesive zone. It is worth noting that the regulation of the DBM can achieve the purpose of suppressing the interaction.