Study of blast furnace heat filterability through coke filling

Abstract

Increase of gas permeability of burden materials column lower part is one of the way of blast furnace heat intensification. Filterability of intermediate slag through coke filling determines the gas permeability of the lower zone and the blast furnace heat running. To study the filterability a methodology was elaborated and implemented, which enabled to estimate reliably the iron ore raw materials behavior in the blast furnace at high temperatures. By laboratory studies influence on the filterability of BF slag melt was determined, when MgO, MnO and CaO adding to the burden, depending on the oxides mineralogical composition. The positive influence of magnesium oxide on the slag filterability has an extreme character, at that the sinter basicity has a considerable influence. The mineral form of magnesium-containing additives introduced into the burden substantially influenced the filterability on heat products in blast furnace. Replace ofsiderite and dolomite by other magnesium-containing materials facilitates to improving of slag filterability through coke filling. Additional input of manganese in the form of manganese limestone or manganese-containing ferritic-calcium flux is an effective mean to improve filterability of sinter smelting products through coke filling. Transfer to hot metal smelting from fluxed pellets and sinter will facilitate heat products filterabilityincrease thanks to close physical andchemical properties of BF burden components in respect of smelting and slag filtering through coke filling.