Multifunctional oxygen lance system and steelmaking method for converter steelmaking

Abstract

The invention belongs to the technical field of iron and steel smelting, and in particular relates to a multifunctional oxygen lance system and a steelmaking method for converter steelmaking, which are suitable for 30-350t converter steelmaking. The method uses a four-layer oxygen lance containing a powder injection tube, and selectively injects carbon powder, anthracite powder or lime powder into the central tube according to the process conditions, and the carrier gas uses N 2 / Ar / CO 2 Or a mixture of several gases, the oxygen lance gas pipeline selectively injects O according to different smelting processes 2 / CO 2 Or a mixture of two gases, carbon powder or anthracite powder injection in the inner tube can increase the heat of the converter molten pool, increase the scrap ratio, and lime powder injection in the inner tube can improve the dephosphorization and desulfurization efficiency of the converter, and reduce the carbon and oxygen accumulation at the end point . The beneficial effect is that, compared with the traditional oxygen lance smelting method, the oxygen lance system has higher flexibility, is suitable for various smelting process requirements, realizes an increase of scrap steel ratio by more than 10%, lime consumption can be reduced by more than 10%, and iron and steel material consumption can be reduced. If it is reduced by more than 3kg, the comprehensive economic benefit of 15 yuan / t steel can be realized.

Description

technical field [0001] The invention belongs to the technical field of iron and steel smelting, and in particular relates to a multifunctional oxygen lance system for converter steelmaking and a steelmaking method. Background technique [0002] At present, the output ratio of crude steel smelted by converters in my country is as high as 90%, and the amount of scrap steel is increasing year by year. Iron and steel enterprises can reduce the consumption of steel materials and increase production by increasing the scrap ratio of converters. However, excessive scrap ratios cannot To meet the heat balance of converter smelting, various ways are used to increase the surplus heat of converter smelting. At present, the ways to increase the ratio of steel scrap mainly include: preheating of steel scrap, adding heating agent (coal, carbon powder and silicon heating agent) to the silo and secondary combustion. There are certain problems in the above methods of increasing the ratio of s...

AI Technical Summary

Problems solved by technology

There are certain problems in the above methods of increasing the ratio of scrap to steel: special equipment is required for scrap steel preheating, and energy consumption and environmental pollution are lost during the scrap steel baking process; The price is higher; secondary combustion can only increase the scrap ratio to a certain extent, and reduce the calorific value of converter gas

During the process of adding lime from the trough, the powdered lime is sucked by the fan, causing loss. The lime block added to the molten pool has a large specific surface area, so it can only be dissolved and slagged by oxygen jet stirring the molten pool.

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