A potential industrial waste-waste co-treatment process was proposed and verified for the recovery of the valuable metals Co, Ni, and Cu from copper smelting slag by utilizing high temperature SO₂ off-gas. Sulfation roasting followed by water leaching under designed thermodynamic conditions was conducted to facilitate the selective formation of Co, Ni, and Cu sulfates while separating iron as oxide. Several parameters were studied such as roasting temperature, roasting time, the addition of Na₂SO₄, and leaching agent. Under the optimized sulfation roasting conditions (Gas flow: 500 mL/min, 5% SO₂ + 20% O₂ + 75% Ar; Roasting temperature: 650 °C; Roasting time: 4 h; Addition of Na₂SO₄: 30%) followed by water leaching (Leaching temperature: 80 °C; Leaching time: 5 h; solid to liquid ratio: 0.05 g/mL), the extraction yields of Ni, Co, and Cu were shown to reach 95.8% and 91.8%, 81.6%, respectively. Furthermore, the sulfation roasting – water leaching process was confirmed on lab-scale as a feasible and efficient way to recover valuable metals and the mechanism was determined and verified from the microstructural evolution. Finally, a potential environmentally friendly industrial process in terms of the energy flow and material flow was presented based on preliminary assessments for environmental benefits, economic benefits, and heat recovery.

提出了一种潜在的工业废料协同处理工艺，并通过利用高温SO ₂废气从铜冶炼炉渣中回收有价金属Co，Ni和Cu进行了验证。进行硫酸焙烧，然后在设计的热力学条件下进行水浸出，以促进选择性分离形成钴，镍和铜的硫酸盐，同时分离出铁氧化物。研究了焙烧温度，焙烧时间，Na ₂ SO _4的添加和浸出剂等参数。在优化的硫酸盐焙烧条件下（气流：500 mL / min，5％SO ₂ +  20％O ₂ +  75％Ar;焙烧温度：650°C;焙烧时间：4 h;添加Na₂ SO ₄：30％），然后水浸（浸出温度：80°C；浸出时间：5 h；固液比：0.05 g / mL），显示Ni，Co和Cu的提取率达到分别为95.8％和91.8％，81.6％。此外，在实验室规模上证实了硫酸盐焙烧-水浸工艺是一种回收有效金属的可行而有效的方法，并从微观结构演变中确定并验证了该机理。最后，根据对环境效益，经济效益和热回收的初步评估，提出了一种在能量流和物料流方面潜在的环境友好型工业流程。