Study and Application of Bottom Blowing Technique of Combined Blowing Converter

The water modelling experiments of 300 t converter concerning combined blowing parameters, the number, and configuration of bottom nozzles are carried out. The results show that the arrangement of 16 bottom nozzles at 0. 40D and 0. 45D (hearth diameter) concentric circles is the reasonable solution. The combined blowing steelmaking technique of 300 t converter has been developed through experiments and studies relating to optimizing the top-bottom combined blowing pattern, the number and configuration of the bottom nozzles, the type selection of bottom nozzle, and bottom nozzle maintenance techniques. The results show that the product of w[c]
• w[o] at endpoint is reduced from 0.00262 to 0.00243, average TFe content is decreased by 2%, phosphorus distribution is raised from 70. 85 to 78. 95, sulfur distribution is raised from 3.43 to 4.32 and manganese content is raised by 0. 02%.