The method of carbon powder mixed injection with a shrouding supersonic oxygen jet was proposed to increase the utilization efficiency of carbon powder and improve the foaming slag operation during the electric arc furnace (EAF) steelmaking process by delivering the carbon powder more deeply into the molten bath. In this study, the fluid flow characteristics of the carbon powder mixed injection with a shrouding supersonic oxygen jet were studied and analyzed using numerical simulations, which were first validated by a cold test experiment. Compared with the conventional carbon powder injection without a shrouding jet, the shrouding supersonic oxygen jet can protect the central gas-powder jet against the entrainment of the surrounding atmosphere, increase the velocity of carbon powder and make the carbon powder cluster together in a longer distance. Furthermore, the industrial application research was carried out in a 50-ton commercial Consteel EAF, and the relative metallurgical effects were also studied. Compared with EAF steelmaking using conventional carbon powder injection without a shrouding jet, the powder consumption, tap-to-tap time, FeO content in the final molten slag and phosphorus content of the final molten steel were reduced by 19.3 kWh/ton, 4 min/heat, 2.6 pct and 1.2 × 10−3 pct, respectively, after using the method of carbon powder mixed injection with a shrouding supersonic oxygen jet.

中文翻译：

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电弧炉炼钢中碳粉混合喷射带罩式超音速氧气射流

为提高电弧炉炼钢过程中碳粉的利用效率，改善发泡渣操作，提出了碳粉混合喷射加罩式超音速氧射流的方法，将碳粉更深地输送到熔池中。 . 在这项研究中，使用数值模拟研究和分析了碳粉混合喷射与覆盖超音速氧气射流的流体流动特性，这首先通过冷试验实验进行了验证。与传统的无护罩射流碳粉喷射相比，护罩超音速氧射流可以保护中心气粉射流免受周围大气的夹带，增加碳粉的速度，使碳粉聚集在一起的距离更远. 此外，在50吨商用Consteel EAF上进行了工业应用研究，并对相关冶金效果进行了研究。与采用传统碳粉喷射不带护罩射流的电弧炉炼钢相比，粉末消耗量、出钢时间、最终熔渣中的 FeO 含量和最终钢水的磷含量降低了 19.3 kWh/ton, 4 min /heat，分别为2.6 pct和1.2 × 10−3 pct，采用碳粉混合喷射的方法和覆盖式超音速氧气射流。