The flow characteristics and postcombustion behavior of a single-flow postcombustion (PC) oxygen lance are of paramount significance to optimal design and operation of the lance but not well understood, and there is also no well-known design criterion for the optimization of the single-flow PC lance. Herein, the design criteria of a single-flow PC lance are first proposed. Then, a 3D fluid model is established combined with a 120 t top-blown converter. The influences of the key parameters of secondary nozzles (i.e., inclination angle, diameter, and number) on the jet characteristics and PC behavior at the steelmaking temperature are studied. Finally, based on the design criteria, an optimal PC lance is designed and its smelting effect is compared with that of the conventional lance by industrial tests. The results indicate that the reasonably designed PC lance can effectively improve the PC zone of CO gas and simultaneously increase both the penetration depth and impact area of the main jet. Compared with conventional lance, the PC oxygen lance can raise the temperature of molten steel by ≈30 °C and reduce the total fe (T.Fe) content in the final slag by 0.86%. Moreover, it has almost no effect on the gas recovery.

中文翻译：

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单流后燃氧枪在120t顶吹转炉的喷嘴设计及应用研究

单流后燃烧 (PC) 氧枪的流动特性和后燃烧行为对氧枪的优化设计和操作至关重要，但尚未得到很好的理解，而且也没有众所周知的单流后燃烧 (PC) 氧枪优化设计标准。 -流PC枪。在此，首次提出了单流 PC 喷枪的设计标准。然后，结合120 t顶吹转炉建立3D流体模型。研究了二级喷嘴的关键参数（即倾角、直径和数量）对炼钢温度下射流特性和PC行为的影响。最后，根据设计标准，设计出最优PC喷枪，并通过工业试验将其熔炼效果与常规喷枪进行比较。结果表明，合理设计的PC喷枪可以有效改善CO气体PC区，同时增加主射流的穿透深度和冲击面积。与传统喷枪相比，PC 氧枪可将钢水温度提高约 30 °C，并使终渣中的总铁 (T.Fe) 含量降低 0.86%。而且，它对气体回收率几乎没有影响。