The current study is focused on developing a two-step pyro-hydrometallurgical process for the recovery of valuable components of electric arc furnace (EAF) slag produced by the steelmaking industry. The first step (hot step) involves carbothermic reduction of the EAF slag to recover iron along with niobium, chromium, and manganese in a metallic phase and titanium, magnesium, and aluminum in an iron-depleted slag phase. The second step (cold step) involves acid baking – water leaching of the iron-depleted smelting slag to recover these metals in an iron-depleted slag phase. Fractional factorial design of experiment and response surface methodology were utilized to find the optimum operating parameters of the two steps, respectively. The optimum operating conditions were determined to be smelting temperature of 1600 ºC, carbon to slag mass ratio of 0.12 g/g_EAFS, and no flux addition for carbothermic reduction and baking temperature of 185 ºC, acid to smelting slag mass ratio of 2.03, baking time of 69.8 min, and water to acid-baked slag ratio of 5.83 for acid baking – water leaching. The metallic phase obtained in the smelting process contains 70.2 wt% iron, 17.3 wt% manganese, 7.0 wt% chromium, and 0.2 wt% niobium. The developed extraction process results in 86.4% titanium and 100% aluminum and magnesium extraction. We expect the findings of this study to help enable the EAF slag valorization using the two-step (hot and cold) pyro-hydrometallurgical process, contributing to sustainable recycling and circular economy.

目前的研究重点是开发一种两步火法湿法冶金工艺，用于回收炼钢行业产生的电弧炉 (EAF) 炉渣的有价值成分。第一步（热步骤）包括对 EAF 渣进行碳热还原，以回收铁以及金属相中的铌、铬和锰，以及贫铁渣相中的钛、镁和铝。第二步（冷步骤）涉及酸焙——对贫铁熔炼渣进行水浸，以在贫铁渣相中回收这些金属。分别利用实验的部分因子设计和响应面方法来寻找两个步骤的最佳操作参数。最佳操作条件确定为熔炼温度为 1600 ºC，_EAFS，碳热还原不加助熔剂，焙烧温度185℃，酸熔渣质量比2.03，焙烧时间69.8min，酸焙-水浸水酸焙渣比5.83。在冶炼过程中获得的金属相含有70.2wt%的铁、17.3wt%的锰、7.0wt%的铬和0.2wt%的铌。开发的提取工艺可提取 86.4% 的钛和 100% 的铝和镁。我们预计这项研究的结果将有助于使用两步（热和冷）火法湿法冶金工艺实现 EAF 炉渣的增值，为可持续循环和循环经济做出贡献。