废旧电路板中有价金属回收试验研究

提出了一种以FeO-SiO₂-Al₂O₃-CaO渣体系为基础的废旧电路板还原熔炼工艺,从减少渣中金属损失及控制性能角度,对渣成分及结构进行调控,研究了熔剂添加量、熔炼时间、熔炼温度、炉渣组成成分对金属回收率的影响。结果表明,在熔剂添加量为原料质量30%、熔炼温度1 450 ℃、熔炼时间75 min、FeO/SiO₂比为1、渣中CaO含量8%条件下,废旧电路板中Cu、Sn回收率分别为91.98%、86.30%,贵金属Au、Ag、Pt在合金相中含量分别可达67.41 g/t、1 020.74 g/t、54.75 g/t。以该渣系为基础还原熔炼废旧电路板的工艺是可行的。

Experimental Research on Recovery of Valuable Metals in Waste Circuit Boards

A reduction smelting process based on FeO-SiO₂-Al₂O₃-CaO slag system was firstly proposed for waste circuit boards. Aiming at reducing slag metal loss and controlling performance, the composition and structure of the slag were regulated, and effects of flux addition, smelting time, smelting temperature and slag compositions on metal recovery were investigated. The results show that with the addition of flux at 30% of the raw materials, the smelting temperature at 1 450 ℃, the smelting time of 75 min, FeO/SiO₂=1 and the CaO content of 8% in the slag, the recovery rates of Cu and Sn from waste circuit boards can reach 91.98% and 86.30%, respectively, and the contents of precious metals (Au, Ag and Pt) in the alloy phase can reach 67.41 g/t, 1 020.74 g/t and 54.75 g/t, respectively. Thus, it is feasible to recover valuable metals from waste circuit boards by using reduction smelting process based on this slag system.