基于共存理论的废线路板火法熔炼渣⁃铜平衡研究

Research on Slag⁃Copper Equilibrium in Smelting of Waste Circuit Board Based on Coexistence Theory

基于炉渣结构离子分子共存理论,结合高温熔炼实验,研究了废线路板熔炼过程中铜、锡及铅在渣⁃铜平衡中的分配规律。以石灰为添加剂的废线路板混合料火法熔炼,其熔渣为CaO⁃SiO_(2)⁃Al_(2)O_(3)⁃FeO四元渣系。结果表明,使用熔渣结构离子分子共存理论,能较好表征该渣系组元的活度;渣中FeO活度随着CaO含量增加先减小后增大,随着FeO含量增加而增大。渣中铜、锡及铅含量与渣中FeO活度成正比;渣中铜、锡及铅含量随着碱度增加先降低后增加,随着FeO含量增加而增加。通过控制熔渣碱度(CaO/SiO_(2))0.6~1.2、FeO含量15%~24%,可有效提高熔炼效果,使渣中铜含量低于0.7%、锡含量低于0.2%、铅含量低于0.2%。

Based on the ion⁃molecular coexistence theory of slag constitution,the distribution rule of Cu,Sn and Pb in slag⁃copper equilibrium during the smelting of waste circuit board(WCB)was investigated by performing high⁃temperature smelting experiments.The slag was CaO⁃SiO_(2)⁃Al_(2)O_(3)⁃FeO quaternion system after the smelting of WCB mixture with the additive of lime.The results show that the activity of the slag system can be better characterized by using the coexistence theory.The activity of FeO in the slag increases after an initial decrease with the increasing of CaO content,and also increases with the increasing of FeO content.The content of Cu,Sn and Pb in the slag is directly proportional to the activity of FeO,and increases after an initial decrease with the increasing of basicity,and increases with the increasing of FeO content.By controlling the basicity(CaO/SiO_(2))within the range of 0.6~1.2,and FeO content within the range of 15%~24%,the smelting effect can be effectively improved,showing the Cu content in the slag less than 0.7%,both Sn content and Pb content in the slag less than 0.2%.