Effect of Oxides of Magnesium and Manganese and the Basicity of the Iron-Ore-Bearing Materials on the Ability of the Smelting Products to Filter Through the Coke Column in Blast Furnaces

One way of increasing the smelting rate in a blast furnace is to increase the gas permeability of the lower part of the stock. Gas permeability in this zone and the smoothness of the furnace’s operation depend on the ability of the intermediate slag to filter through the coke column. A method of studying filterability has been developed and introduced, the method making it possible to reliably assess the behavior of the iron-orebearing materials in a blast furnace at high temperatures. It was established by laboratory studies and confirmed by factory tests that the filterability of molten blast-furnace slag is affected by the presence of the oxides MgO, MnO, and CaO, which are added to charge that is used to make sinter. The magnitude of this effect depends on the composition of the minerals that contain these oxides.