Effect of Gas Distribution Mode on Bath Stirring and Mixing in a Bottom‐Blown Converter

Abstract

Currently, converter steelmaking is the main method for steelmaking, the performance of bottom blowing and bath stirring would obviously affect the efficient and stable smelting of high‐quality clean steel. At present, the uniform bottom gas distribution mode is mostly applied in converter steelmaking, which would probably lead to unstable stirring performance and inadequate mixing at the later stage of furnace campaign. Therefore, a nonuniform bottom gas distribution mode is proposed herein, which intends to improve the mixing efficiency. The physical and numerical simulations are carried out to investigate the influence of gas flowrate, nozzle configurations, and bottom gas distribution mode on bath stirring and mixing. In the results, it is shown that the large and asymmetric circulation flow is formed due to the nonuniform gas distribution for each nozzle, which enhances stirring in the horizontal direction and ultimately improves mixing efficiency. Compared with the uniform gas distribution mode, when gas distribution ratio of nonuniform bottom blowing is 3:1, the mixing time is reduced by 29%, the average velocity of liquid steel is increased from 0.0342 to 0.0404 m s−1, the ratio of the dead zone is decreased by 26.23%, and the proportion of active flow region is added by 10.49%.