Quality Improvement of Sintered Ore in Relation to Blast Furnace Operation

High productivity operation of a blast furnace requires enhancing reducibility and improving reduction behavior at high temperatures of sintered ore. Analysis results of sintered ores with extensive ranges of chemical composition showed that reduction behavior of sinter depended on their chemistry and pore structure as a result of changes in the amount of liquid phase, viscosity and smelting-reduction rate of formed slag containing 'FeO'. Sinter with High Fe content, proper basicity range (1.5-2.0), low Al 2 O 3 content and fine pores below 15μm in size had superior reduction behavior. Finally, sinter with low SiO 2 , low MgO and low Al 2 O 3 has been developed and manufactured in all works in Nippon Steel, resulting in improvement of blast furnace operation.