Effect of Ternary Basicity of Iron Ore-Fluxed Pellets on Melting and Softening Properties in a Blast Furnace
Fábio R. Silva, Leandro Rocha Lemos, Paulo de Freitas Nogueira, Marcelo Bressan
Abstract
Abstract The cohesive zone is a region of low permeability in a blast furnace. This study shows the impact of the chemical composition of pellets on the metallurgical processes occurring in this region during the iron ore reduction process. Sixteen pellets containing varying contents of MgO, CaO, and SiO 2 were investigated. The results indicate that increasing the MgO content of pellets improves their high-temperature properties; e.g. , reduction degree and softening temperature. Modern equipment was used to replicate the phenomena that occur in the cohesive zone to measure the softening temperature, pressure drop, and the reduction degree of pellets at elevated temperatures and different pellet basicities. These experimental results were used to develop mathematical correlations between parameters related to high-temperature properties and the ternary basicity of the pellets ((CaO + MgO)/SiO 2 ). Defining such relationships will facilitate evaluating the effects of pellet chemical composition on blast furnace processes.