采用HF酸浸蚀沉降的方法从单晶硅切割废浆料中回收硅粉

Recycling of silicon powder from cutting slurry waste using HF etching sedimentation method

采用HF酸浸蚀沉降的方法回收单晶硅切割废浆料中的硅粉。系统地研究了在回收硅粉过程中,HF酸的浓度,HF酸处理的时间,以及在HF酸浸蚀沉降处理前的超声震荡时间等实验条件对回收率和纯度等性能的影响因素。研究表明,在HF酸浓度为2%,HF酸处理时间24h,超声震荡时间60min的条件下,回收得到的粉体中硅的纯度可以达到82%(质量分数),且回收率可以达到62%的水平。通过此方法可以实现从切割废浆料中回收硅粉。

HF acid etching sedimentation process was designed to recycling of silicon from cutting slurry waste in poly-silicon slicing process.The effects of several operational variables on the recovery rate and yield of silicon kerfs were systematically investigated,including HF acid concentration,HF processing time.Also the effects of dispersion time of ultrasonic agitation prior to the HF acid etching sedimentation process were also studied.In considering the acceptable levels of both recovery rate and yield,a product with Si recovery rate of 82wt% and the yield 62% is obtained under the operating conditions by setting HF acid concentration at 2%,HF processing time at 24h,the agitation time at 60min.It is indicated that through this method we can recycle the Si powder from slurry waste.