大型转炉双角度氧枪喷头高供氧强度炼钢

High oxygen supply intensity steelmaking with dual-angle oxygen lance nozzle in large converter

为了把宝钢炼钢厂300t转炉的氧流量由60000提高到69000m^(3)/h,设计了6孔双角度氧枪喷头。根据第一个双角度喷头的试验结果,结合实验室内进行的氧枪喷头射流流场测定、射流与熔池作用的水模研究,对喷头设计进行了改进。为制定正确的供氧制度和喷头设计,对宝钢一炼钢的管道压力损失进行了测定。经过优化的3号6孔双角度喷头的主要参数为,氧流出口马赫数Ma≥2.1,小角度喷孔的氧流量不低于总供氧流量的57%,大角度喷孔夹角不小于13°,小角度喷孔夹角为10°左右。利用3号6孔喷头炼钢效果为,氧流量为69000m^(3)/h,吹氧时间平均缩短2.0min/炉,脱磷率平均为87.5%,氧枪喷头寿命平均为190次。通过这次研究工作掌握了大型转炉高供氧强度3.833m^(3)/(t·min)吹炼的双角度6孔喷头设计制作和吹炼操作技术。

In order to increase the oxygen flow rate of the 300 tconverter in Baosteel’s steelmaking plant from 60000 to 69000 m^(3)/h,a 6-hole dual-angle oxygen lance nozzle was designed.Based on the test results of the first dual-angle nozzle,combined with the measurement of the jet flow field of the oxygen lance nozzle in the laboratory,and the water model study of the effect of the jet and the molten bath,the nozzle design was improved.In order to formulate the correct oxygen supply system and nozzle design,the pipeline pressure loss of Baosteel No.1 Steelmaking Plant was measured.The main parameters of the optimized No.36-hole dual-angle nozzle are,oxygen outlet Mach number Ma≥2.1,the oxygen flow of the small-angle nozzle is larger than 57%of the total oxygen flow,and the angle of the large-angle nozzle is larger than 13°,the angle of the small-angle nozzle is about 10°.The effect of steelmaking with No.36-hole nozzle is,oxygen flow rate is 69000 m^(3)/h,oxygen blowing time is shortened by 2.0 min/ch on average,dephosphorization rate is 87.5%on average,and oxygen lance nozzle life is 190 times on average.Through this research work,we have mastered the design and manufacture of the dual-angle 6-hole nozzle for high oxygen intensity blowing(3.833 m^(3)/(t·min))and the blowing operation technology of the large converter.