脱磷专用转炉的氧枪设计及研究

Design and Research of Oxygen Lance in Dephosphorization Converter

脱磷专用转炉通常采用脱磷氧枪促进化渣,提高脱磷率,实现铁水预脱磷。设计了马赫数为1.9、氧枪流量为14 500m3/h的4孔脱磷氧枪,利用Fluent软件模拟了脱磷氧枪的速度场、温度场和密度场等分布。模拟发现:4孔脱磷氧枪在枪位为1.5m时,射流速度约为115m/s,当射流速度为100m/s时,最大射流半径为0.28m。在此基础上,将脱磷氧枪用于120t脱磷专用转炉的生产过程,取得了良好的冶炼效果:可控制脱磷终点温度为1 370℃左右;转炉终点碳的质量分数大于2.8%时能满足脱碳炉热量要求;半钢磷的质量分数平均可达到0.018%,平均脱磷率可达到79.2%。与传统单渣工艺相比,采用此工艺不仅能降低炼钢终点磷含量,也能保证脱磷的稳定性。

Special oxygen lance for dephosphorization was used in dephosphorization converter in order to promote slagging improving dephosphorization rate and to realize the pretreatment of dephosphorization. Four-hole dephos-phorization oxygen lance with the Mach number of 1.9 and flow rate of 14500m^3/h was designed, whose velocity field, temperature field and density distribution were simulated by Fluent software. It is found that oxygen jet speed is about 115 m/s at the lance height of 1.5 m, when jet speed is 100 m/s, the maximum jet radius is 0.28 m. Based on the simulations, the dephosphorization oxygen lance was used in 120 t converter smelting process, which has ob- tained some good smelting effects. The end-point temperature should be controlled at 1370 ℃ or so. The mass percent of end-point carbon in dephosphorization converter must be more than 2.8 % to satisfy the heat requirements of decarburization converter. The average mass percent of phosphorus in semi-steel is 0. 018% and dephosphorization rate can be reached 79.2%. Compared with the traditional single slag process, this steelmaking technology can not only reduce the phosphorus content, but also guarantee the stability of dephosphorization.