Abstract: The technical characteristics of electric arc furnace steelmaking with direct reduced iron as a substitute for scrap steel are analyzed， and the main factors affecting the smelting power consumption are expounded . The results indicate that a large amount of steel left in melting pool （≥ 40%） and intensive mixing such as enhanced oxygen supply， bottom blowing， and electromagnetic stirring are important ways to promote melting and shorten the tap-to-tap cycle （which can be shortened by 8%-10%）. The proportion of direct reducing iron exceeds 30%， continuous feeding should be used. The feeding speed in the early and middle stages of smelting is generally equal to the melting speed of 28-33 kg/min （power supply power is 1 MW）. It is necessary to match lime and dolomite to prevent the erosion of slag line， and the whole smelting process should be sprayed with carbon foam slag to ensure the power supply efficiency. To reduce power consumption of smelting， direct reduction iron with high C content， high metallization rate， low SiO₂ content， low P content， low S content， and higher temperature should be used as much as possible within a certain suitable range （that is， w［C］ 1%-4.5%， metallization rate ≥ 90%， w［SiO₂］ ≤ 6%， w［P］ ≤ 0.1%， w［S］ ≤ 0.04%）. The compact short process combining direct reduction iron vertical furnace and electric arc furnace is an important direction for low-carbon， energy-saving， and clean production.

Key words: Electric Arc Furnace （EAF）, Direct Reduction Iron, Power Consumption, Low Carbon and Energy-saving, Purification

摘要： 分析了直接还原铁作为废钢替代品进行电弧炉炼钢的工艺技术特征，并阐明了影响冶炼电耗的主要因素。结果表明，熔池较大留钢量（≥40%）和诸如强化供氧、底吹和电磁搅拌的强化搅拌始终是促进熔化和缩短冶炼周期（可缩短8%～10%）的重要手段。直接还原铁比例超过30%宜采用连续加料，冶炼前期和中期加料速度一般等于熔化速度28～33 kg/min（供电功率1 MW），需匹配石灰和白云石以防渣线侵蚀，冶炼全程应喷碳使泡沫渣埋弧操作以保证供电效率。为降低冶炼电耗，应控制w［C］1%～4.5%、金属化率≥90%、w［SiO₂］≤6%、w［P］≤0.1%、w［S］≤0.04%，使用高C、高金属化率、低SiO₂、低P、低S和较高温度的热直接还原铁。采用直接还原铁竖炉和电弧炉相结合的紧凑短流程工艺是低碳节能和洁净化生产的重要方向。

关键词: 电弧炉, 直接还原铁, 电耗, 低碳节能, 洁净化