Method based on high-silicon high-phosphorus molten iron converter low slag material consumption to melt low-phosphorus steel

Abstract

The invention relates to a smelting technology method of a steel technological process and specifically relates to a method based on high-silicon high-phosphorus molten iron converter low slag material consumption to melt low-phosphorus steel. The method comprises the following steps: utilizing single-slag operation under the conditions that Si of molten iron putting into a furnace is larger thanor equal to 0.55% and smaller than or equal to 0.8% and P of molten iron putting into the furnace is larger than or equal to 0.17% and smaller than or equal to 0.22%; making a molten iron temperaturelarger than 1250 DEG C and a scrap steel ratio larger than 25%; utilizing a less-slag material, adding the less-slag material into a melting model and controlling the adding amount of an auxiliary material. When Si of general molten iron putting into the furnace is larger than or equal to 0.6% or P of the general molten iron putting into the furnace is larger than or equal to 0.12%, a duplexing method or a double-slag method is utilized by a converter. Under the situations of molten-iron-free three-removal pretreatment and converter duplexing method dephosphorization, operation of the method disclosed by the invention utilizes a single-slag method; under the premises that converter lime consumption is smaller than 40kg / t and a new slag material consuming total amount is smaller than 70kg / t, the condition that P is smaller than 0.012% when a smelting point C is larger than or equal to 0.065% is ensured at the same time. The method disclosed by the invention can effectively reduce novelslag material consumption of high-silicon high-phosphorus molten iron converter smelting, is favorable for reducing industrial waste generation and reduces production cost of per ton of steel.

Description

technical field [0001] The invention relates to a smelting control method of an iron and steel process flow, in particular to a method for smelting low-phosphorus steel based on a high-silicon, high-phosphorus molten iron converter with low slag consumption. Background technique [0002] The blast furnace smelting process is a reducing atmosphere, and the phosphorus in the blast furnace raw materials (iron ore, sinter, pellets, coke, lime, etc.) is reduced into molten iron, and the blast furnace smelting process cannot dephosphorize. Under the condition of no "three removal" pretreatment of molten iron, phosphorus in molten iron is mainly oxidized and removed by converter. The blast furnace molten iron directly enters the converter for blowing. Since the molten iron contains relatively high elements such as Si and P, the converter not only needs to decarburize and heat up, but also undertakes the tasks of desiliconization and dephosphorization. The silicon content of molten...

AI Technical Summary

Problems solved by technology

Low metal yield, high solvent consumption, heavy gun sticking and slopping due to this high slag blowing method

The existence of these problems has greatly increased the cost of steelmaking

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