| 摘要 |
<p>When manufacturing liquid steel from highly concentrated iron-ore concentrate, especially iron-ore concentrate containing phosphorous, a charge material is produced by sintering a mixture comprising substantially the afore-mentioned concentrate and basic slag-forming agents including CaO and MgO. The composition of the mixture is adjusted so that the charge material contains calcium oxide in an amount corresponding to at least 35% of the total weight of the non-iron oxide content of the charge material, and calcium oxide and magnesium oxide in a total amount corresponding to at least 55% of the total weight of the non-iron oxide content of the charge material, and also exhibits a weight ratio of CaO: MgO of at least 1.3. The charge material is reduced in solid phase to form sponge iron having a degree of metallization of at least 80 %,whereafter the sponge iron, optionally together with another iron-bearing material, is smelted in a steel furnace under such conditions as to maintain in the slag formed during the smelting process an iron-oxide content of at least about 5% by weight, and the resultant liquid steel and slag are separated from one another.</p> |
