电子废弃物脉动气流分选的实验研究

Experimental Study of Separation of Electronic Waste in the Pulsing Airflow

金属与非金属材料的分离是电子废弃物资源化的关键环节．探讨了脉动气流分选机理，利用高速摄像机和颗粒高速动态分析系统，研究了在1．0和2．0Hz频率下，脉动气流分选机中物料颗粒的分选过程．结果表明，颗粒的位移、速度、加速度呈现明显的周期性变化，并且周期与脉动气流的周期一致．物料颗粒通过不断累积脉动气流的加速度效应实现按密度分离．采用脉动气流分选机对2．0～0．5mm粒级的废弃电路板破碎物料进行了分选实验，并利用Design—Expert6．0软件进行了正交实验设计和分析，得出了分选效率与不同操作变量之间的二次方模型，结果表明气流速度和脉动频率以及两者的交互作用对分选效率具有显著影响，操作条件优化后，分选效率达到89．97％．

The separation between metal and non-metal materials is the key process for the reclamation of electronic waste. The separation mechanism of particles with different properties was discussed in a pulsing airflow classifier using a high speed camera and particle dynamic analysis system under a frequency of 1.0 Hz and 2.0 Hz, respectively. The results show that the displacement, speed and acceleration of the particle changed regularly and the change cycle is matched with the cycle of pulsing airflow. The accumulation of acceleration effect is contributed to the separation of particles in the pulsing airflow. The separation tests of 2.0-0. 5 mm electronic waste in pulsing airflow classifier were conducted. The orthogonal experiments were designed and their results were analyzed using a Design- Expert 6.0 software. A Quadratic model between separation efficiency and different operation variable was proposed, which shows that the interaction of airflow velocity and pulsing frequency on separation efficiency was significant. The separation efficiency of 89.97 % was achieved under the optimum conditions.