Behaviors of Melt Formation and Pore Occlusion of Artificial Iron Ore Agglomerates at High Temperatures, and Reducibility

Energy consumption and CO2 emission from the iron and steel industry in Japan are each 12.5% in comparison to them of the whole Japan. Blast furnace process occupies a half of them in the iron and steel industry. Improvement of gaseous reduction for iron ore agglomerates at high temperatures is very effective to decrease in energy consumption and CO2 emission from blast furnace. In the present study, reducibility at high temperatures of 1100, 1150, 1200℃ and observation of pore occlusion by molten slag were investigated with artificial iron ore agglomerates including CaO and SiO2, of which have micro pores, macro pores and a penetrated hole. Influence of the melt formation on the reducibility is very strong, and the reduction rate at 1100℃ is faster than them at 1150 and 1200℃ although the reduction rate constant is more fast in proportion to temperature up. At 1200℃, macro pores become isolation pores by melt. On the other hand, a penetrated hole with 1 or 2mm is not closed by melt, and improves the reducibility. Penetrated hole is very effective to improve the reducibility of iron ore agglomerates at high temperature zones with melt formation.