A kind of sintered ore and blast furnace smelting method thereof

Abstract

The invention provides sinter and a blast furnace smelting method thereof, and belongs to the technical field of blast furnace ironmaking. The sinter comprises, by weight percent, 53%-55% of TFe, 10.5%-12.5% of CaO, 5.5%-7.5% of SiO2, 1.5%-2.5% of MgO, 2.5%-3.5% of Al2O3, smaller than or equal to 0.1% of ZnO, 0.125%-0.145% of Cr, smaller than or equal to 0.1% of P and 0.45%-1.0% of Mn. According to the sinter, the content of Cr and the content of Mn are increased according to the requirement of steelmaking for the content of Cr and the content of Mn of molten iron, and therefore the number of Cr and Mn alloy materials needing to be added in steelmaking is reduced, and the steelmaking production cost is reduced.

Description

technical field [0001] The invention relates to the technical field of blast furnace ironmaking, in particular to a sintered ore and a blast furnace smelting method thereof. Background technique [0002] In steelmaking, chromium is a precious metal element and a beneficial element in steel, which can increase the corrosion resistance of steel; manganese can increase the strength and hardness of steel, can be used as a deoxidizer for steelmaking, and can also play a role in desulfurization. [0003] In ironmaking, in order to reduce the production cost of ironmaking, we firstly start by reducing the purchase cost of raw materials and fuels. Through market inquiries, we found two medium-quality iron ore powders with high cost performance: Indonesian powder and super special powder; Indonesian powder The powder is Indian fine-grained powder ore, but it does not meet the Indian coarse particle size standard. The grade ranges from 40 to 63.5%. It belongs to hematite, and the high...

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Problems solved by technology

[0004] Applying Indonesian powder and ultra-special powder to ironmaking sintering materials can not only reduce ironmaking production costs, but also reduce the amount of Cr and Mn alloy materials that need to be added in steelmaking, reducing steelmaking production costs; however, Indonesian powder Contains Cr and Al 2 o 3 Higher, super special powder contains Mn and Al 2 o 3 Higher, these three elements have varying degrees of influence on blast furnace smelting: Chromium is often represented by Cr in ores 2 o 3 The state exists, and the reduction rate in the blast furnace can reach 80% to 95%. After the content of Cr in ironmaking increases, first of all, because the melting point of chromium is higher at 1857 ° C, it is a refractory substance. From Fe-Cr-C It can be seen from the ternary phase diagram that the liquidus temperature of ferrochrome alloy is higher, so at the same tapping temperature, the fluidity of molten iron with high chromium content is not as good as that of ordinary molten iron, which makes the fluidity of molten iron and slag worse. Secondly, due to The reduction reaction of chromium-containing minerals will absorb a large amount of heat, which will affect the smooth progress of smelting; the increase of Mn content can effectively reduce the melting temperature of iron slag and improve the fluidity of iron slag. It is usually used as a conventional cleaning agent for blast furnaces, which can effectively solve Negative effects of high Cr hot metal smelting; Al 2 o 3 After the content of Al increases, it will lead to Al in the blast furnace slag 2 o 3 The increase will affect the desulfurization ability of slag and the flowability of slag