Study On Slagging Regime And Process Optimization Of LongSteel Converter

The purpose of slagging is to remove sulfur and phosphorus in molten steel, reduce to the splash and protect lining. Slagging regime and process optimization is the important way of achieving high efficiency and energy saving about converter production. Slagging process is related to the raw materials, addition amount and the time of raw materials, slag component design, the type and quality of lining materials, and various other aspects. To improve the ecnomical results and reduce the cost, process optimization should be the main research aspectfor.According to results of LongSteel production, steel-making process analysis software were used to analyse the data which came from the raw materials (such as molten iron, scrap steel, lime, etc.) and steel-making operations in converter slagging process (the amount of lime addition, slag components, etc.). The material balance and the thermal balance were carried out. single-factor-regress analysis was used to optimize the technologiccal parameters. Based on these, the related measures are suggested and put into practice. Good results are obtained. The major conclusions are as following:1,Among the steel-making raw materials of LongSteel, lime is in poorer quality. The silicon ,sulfur, phosphorus are at relatively low level and stable. So the task of desulfurization and dephosphorization is easy to be completed. The granularity or active of lime should be improved because the production cycle and the time of Oxygen blowing is being shorten.2,The thermal balance of process is affected mainly by amount of molten iron , iron ore and silica content in hot metal. The main factors to effect to amount of slag and alkalinity are lime component, silicon content of the molten iron, amount of lime and iron. Shese should be controlled carefully.3,In the conditions of LongSteel, it is foound that alkalinity of the ending-slag at 2.6～3.0, FeO content at 15%, temperature at about 1650℃, and with the use of sludge ball and the active lime, slaging is quick and stable, and production speed can be meet well.4,With the optimization, the final results is improved obviously. Metallic material and lime are reduced by 10kg/t and 6.29 kg/t relatively. Slag splashing is put into use successfully and the highest lifespan of converter lining achieved 21129.