基于微波预处理的废弃电路板破碎特性

Broken characteristics of waste circuit boards with microwave pretreatment

采用扫描电镜与激光粒度分析仪对比分析微波预处理前、后废弃电路板颗粒形貌与粒度分布规律;以破碎产物的粒径分布为指标,设计单因素实验,探讨不同微波辐照功率、辐照时间以及破碎时间对废弃电路板破碎效果的影响。结果表明:微波预处理可有效促进废弃电路板的破碎,当辐照功率为700 W时,<0.5 mm粒级的破碎颗粒的质量分数为45.8%,相比未预处理的增加19.97%;当辐照时间为90 s时,<0.5 mm粒级的破碎颗粒的质量分数为47.2%,相比未处理的增加21.37%;经微波预处理后的废弃电路板结构破坏明显,表面粗糙,微裂纹生长发育,而破碎后的颗粒细小,结构松散,金属与非金属成分解离明显。

The particle morphology and particle size distribution of waste circuit boards before and after microwave pretreatment were analyzed by scanning electron microscope and laser particle size analyzer.The particle size distribution of broken products was taken as the index.A single factor experiment was designed to investigate the effects of different microwave irradiation power,irradiation time and break time on the broken effect of waste printed circuit boards.The results show that microwave pretreatment can effectively promote the broken effect of the waste circuit boards.When the irradiation power is 700 W,the content of less than 0.5 mm particles is 45.8%of mass fraction,which is 19.97%higher than that of the untreated condition.When the irradiation time is 90 s,the content of less than 0.5 mm is 47.2%of mass fraction,which is 21.37%higher than untreated condition.After microwave pretreatment,the structure of the discarded circuit board is obviously damaged,the surface is rough,and the microcracks grow and develop.The broken particles are fine and loose,and the decomposition of metal and nonmetal is obvious.