废弃电路板选择性破碎基础研究

Selectivity Crushing of Discarded Printed Circuit Boards

废弃电路板的资源化是电子废弃物资源化研究的重点和难点.介绍了电路板的组成、各种成分的力学性质、界面特性,进行了电路板冲击特性试验,探讨了其解离机理.提出了用剪切破碎机和锤式破碎机实现电路板的粗碎和选择性破碎.结果表明:当筛网为5 mm,锤式破碎机的线速度为13 m/s,转速为2 600 r/min时,细粒级产率小,小于0.074 mm物料占7.88%;各粒级金属品位随着粒度的减小而降低,72.77%的金属主要分布在0.5～2 mm粒级.研究结果为后续的干法分选工艺提供了条件.

The reutilization of the discarded printed circuit boards （PCBs） is very important. The components, mechanical properties of the different components, and interface characteristics of PCBs were introduced. The experiments on impact property of PCBs were conducted, and the liberation mechanism of PCBs was discussed. A sheared double-toothed roll and a hammer crusher were used to achieve the liberation of metals from PCBs. The results show that when the screen aperture mesh is 5 mm, linear speed of the hammer crusher is 13 m/s and rotation speed is 2 600 r/min, the yield of fine particles of -0. 074 mm is only 7.88%. The grade of metals of each grain size decreases with the reducing of grain size, and the metals of 72.77% are distributed in that of 0.5-2 mm, which provides a basis for dry separation process.