Mathematical model of reasonable adjusting tuyere parameters of blast furnace and measures

The reasonable adjustment of tuyeres is benefit for blowing through center and activity of large BF hearth. At present,some views of actual operation were proposed that depth of raceway was increased by increasing the length of tuyere. And also blast velocity and kinetic energy could be increased by decreasing the area of tuyere. A mathematical model of adjusting tuyere parameter was established. Based on a domestic BF with volume of 3 200 m3,the blast volume,velocity and kinetic energy of each tuyere were analyzed by adjusting one tuyere's length and area and multiple tuyeres' size at the condition of constant total blast volume. It was found that blast volume,velocity and kinetic energy of the adjusted tuyeres would be decreased by increasing their lengths. The blast volume of the tuyeres would be reduced by decreasing their areas. The blast velocity and kinetic energy of the adjusted tuyeres could be enhanced with decreasing more tuyeres' areas. However,the blast parameters of unadjusted tuyeres would be improved even more. The parameters of adjusting tuyere for this BF were given quantitatively according to this model,which could be utilized to control uniformity of hearth gas flow and maintain BF stable and smooth.