线路板粉末风选过程气固两相流模拟及实验

Gas-solid two-phase flow simulation of waste printed circuit board powder pneumatic separation process and experiment

针对线路板破碎粉末的特点，提出了一种通过风力分选实现废旧线路板中金属和非金属分离的方法．分别采用RNGk-ε模型、颗粒轨道模型模拟气流场和固体颗粒，模拟结果显示风选器腔体处于旋风状态，风压随着风选器半径和高度的增加而升高，至风选器高度为1．2m附近达到峰值．开展线路板粉末风选实验，通过模拟分析和实验分别得到不同粒径、不同叶轮转速下的优化工艺参数，结果表明粒级对实验结果的影响最大，当线路板粉末粒径为0．125—0．212mm、叶轮转速为200r／min时，金属回收率最高达到96．5％．最后进行分选效果的实验一模拟对比分析，验证了模拟的有效性及分选方案的可行性．

A method of separating metal powder and resin through pneumatic separation was presented according to the characteristics of waste printed circuit board powder. RNG k-ε model and unsteady tracking model were used respectively to simulate the gas flow field and the solid particles. Simulation results showed that the pneumatic separator cavity was in the whirlwind state. Wind pressure was increased with radius and height increasing, and reached the peak at the height of 1.2m. The printed circuit board powder pneumatic separation experiment was carded out and the optimal technological parameters which were chosen from the different particle sizes and impeller rotate speed were obtained. The results showed that particle fractions had the most important influence on separation effect, and the maximal metal recovery rate reached 96.5% when particle sizes were 0.125-0.212mm and the impeller speed was 200r/min. Finally, through the correl＇ation analyzing of experiment and simulation results, the validity of the simulation was verified, and the separation scheme was proved to be feasible.