Multifunctional oxygen lance system for converter steelmaking and steelmaking method

Abstract

The invention belongs to the technical field of steel smelting and particularly relates to a multifunctional oxygen lance system for converter steelmaking and a steelmaking method. The multifunctionaloxygen lance system and the steelmaking method are suitable for converter steelmaking of 30-350 t. According to the steelmaking method, a four-layer oxygen lance internally comprising powder spray pipes is used, according to technological conditions, a center pipe selectively sprays and blows carbon powder or smokeless pulverized coal or lime powder, carrier gas adopts N2 or Ar or CO2 or mixtureof the N2, Ar and CO2, and an oxygen lance gas pipeline selectively sprays and blows O2 or CO2 or the mixture of the O2 and the CO2 according to different smelting technologies; an inner layer pipe sprays and blows the carbon powder or the smokeless pulverized coal so that heat of a converter molten bath can be increased, and the scrap ratio can be improved; the inner layer pipe sprays and blows lime powder so that the dephosphorization efficiency and the desulphurization efficiency of the converter can be improved, and the oxygen volume of end point carbon can be reduced. The multifunctionaloxygen lance system for converter steelmaking and the steelmaking method have the beneficial effects that compared with a traditional oxygen lance smelting method, the oxygen lance system is higher inflexibility and suitable for various smelting technology demands, it is achieved that the scrap ratio is increased by over 10%, the consumption of lime can be reduced by over 10%, and the consumptionof a steel material can be reduced by over 3 kg, and the composite economic results can reach 15 yuan per ton of steel.

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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