A method for reducing
slag viscosity during
blast furnace smelting belongs to the field of ironmaking technology. This invention solves the problem that excessively high
slag viscosity hinders desulfurization and makes
slag discharge difficult. Specifically, it includes the following steps: S1: Increasing the slag temperature from the original 1530℃ to above 1550℃; S2: Controlling the basicity of the slag, which was originally 1.20 to 1.28 times higher, to between 1.15 and 1.25 times higher; S3: Increasing the MgO content in the original slag from 6% to 8% to 12%; S4: Reducing the FeO content in the original primary slag from 35% to ≤22%; S5: Reducing the Al2O3 content in the original slag from 20% to ≤19%; S6: Controlling the CaF2 content in the original slag from 1.0% to 1.0% to 2.0%. This invention, through precise control of the composition, maintains suitable
viscosity and surface properties in the slag. It significantly improves the desulfurization reaction efficiency and desulfurization capacity of slag, and improves the quality of molten iron; moreover, the optimized viscosity range, combined with the increased tapping frequency, ensures that slag and iron can be smoothly separated and discharged, promoting efficient
smelting.