METHOD OF BLAST FURNACE SMELTING ON MAGNESIAN-ALUMINOUS SLAGS Russian patent published in 2000 - IPC

FIELD: ferrous metallurgy, particularly, methods of blast furnace smelting. SUBSTANCE: method includes charging of burden consisting of coke and iron-ore materials with redistribution of amount of magnesian-aluminous sinter with different content of magnesium oxide and with change of ratio of types of iron-ore materials in radial direction; smelting of burden; blowing of high-temperature combined blast; maintaining temperature of final slags exceeding liquid temperature by 200-300 C; tapping of pig iron and slag. In so doing, at increase of Al₂O₃/MgO ratio in magnesian-aluminous slags by 0.1 unit above 1.3 units, amount of raw material with Al₂O₃/MgO ratio in excess of 1.3 units is reduced in central zone of furnace by 1.3-1.5%, and it is correspondingly increased in periphery zone. Amount of raw material with Al₂O₃/MgO ratio below 1.3 units is reduced by 0.5-0,7% in periphery zone, and it is increased correspondingly by the same value in central zone. In this case, amount of iron-ore material and their types in intermediate zone are not changed. EFFECT: reduced cost of smelting of pig iron. 1 tbl, 1 ex