Research on Top and Bottom Mixed Blowing CO2 in Converter Steelmaking Process

Based on the analysis of reaction mechanism between CO2 and molten pool elements at the steelmaking temperature, and on the calculation of materials and heat balance during converter steelmaking process with blowing CO2, a new technology which uses CO2-O2 as top gas and CO2 as bottom gas in a converter was proposed and experimented in a 30?t converter. It is found that the new technology is feasible absolutely, the amounts of smoke dust and T-Fe are reduced by 11.15% and 12.98% on average, the contents of nitrogen and phosphorus are decreased by 50% and 23.33% respectively, iron loss of slag is lowered by 3.10% and oxygen consumption is reduced remarkably. This research will provide a new blowing method for BOF steelmaking process, which can save steelmaking energy consumption and reduce smelting cost.