【作者】 孙伟光；

【导师】 李玉文；

【作者基本信息】 东北林业大学 ， 环境科学， 2008， 硕士

【摘要】 随着我国废旧电器数量的增加,废弃的印刷线路板(废PCB)也在急剧增加。废弃PCB中含有大量的贵金属,可以被回收利用;同时,又含有多种重金属和有毒有害物质,处理不当会严重污染环境。目前,废弃印刷线路板回收处理技术主要包括三类:热处理法、化学处理法和机械物理处理法,但都存在回收效率偏低的问题。本文研究了印刷线路板中贵重金属回收工艺的主要部分:印刷线路板的解离,破碎物料的气流分选、分选产品有机组分的去除。通过实验对贵重金属的回收条件做了优化,提高了回收效率,为今后走向工业化提供了重要理论基础。解离实验结果表明:破碎后的物料主要集中在0.074～0.125mm,0.125～0.25mm,0.25～0.42mm,0.42～0.84mm的4个粒径范围;粒径小于0.84mm的废弃印刷线路板破碎料中金属和非金属基本解离;不同破碎时间下,随着时间增加,金属解离度也随之增加,但到了一定时间(130s),解离度变化不大;在最低转速下,金属解离度不够理想,在大于2000r/min的转速下就能达到较理想的分离效果。气流分选技术对废弃印刷线路板破碎料有较好的分选富集作用,通过计算确定出不同粒径下的最佳操作气速:0.074～0.125mm,0.125～0.25mm,0.25～0.42mm,0.42～0.84mm 4个粒径对应的最佳分选气速分别是0.24m/s,0.28m/s,0.57m/s和0.71m/s,铜的回收率分别为90.56%,85.34%,86.28%,80.33%。火法实验结果表明:火法焚烧可以有效去除物料中有机组分,即在冶炼中产生有毒有害气体的组分;在相同的加热时间下(60min),得出在600℃时为最优加热温度;在相同的温度(600℃)下进行试验,得出物料在加热40min的时间内能够充分燃烧。更多还原

【Abstract】 With the rapid growth of waste electrical and electronic equipment(WEEE) in our country, the quantity of waste printed circuit board(PCB) is increasing sharply in recent years.Lots of precious metals were contained in the PCB and can be recycled as resources,at the same time, large amounts heavy metal and other toxic substances were contained in the PCB and may pollute environmental severely without appropriate treatment.There are three kinds of recycling techniques in recent:heat treatment,chemistry processing and mechanical treatment. Lower recycling efficiency was feature in these techniques.This paper studies three main parts of the metal recovery process in the PCB:the PCB dissociation,flow separation of broken materials,remove the organic components of separated products.For each part of the experiment,all of the experimental conditions for recycling metals have been optimized,and the recycling efficiency was heightened significantly,the experimental results provide theoretic foundation for industrialization in the future.Liberation experimental results show that:the crushed materials mainly concentrated in the size of 0.074 to 0.125 mm,0.125～0.25mm,0.42mm to 0.25,0.42 to 0.84mm;The metal and non-metallic in the material smaller than 0.84 mm are basically separated;At different broken time.as the time increases,metal liberation degree also will be increased gradually,but at a certain period of time(130 s),the liberation degree change little;In the minimum speed, metal liberation is not in expectation,when the rotate speed is over 2000r/min,can reach an ideal separation results.Dealing with the printed circuit board scrap by using air separation technology have achieved separation enrichment effectively,different size can be identified by calculating the optimum operation of gas velocity:in the size of 0.074 to 0.125mm,0.125～0.25mm,0.42mm～0.25,0.42 to 0.84mm,the better separation gas velocity is 0.24 m/s,0.28m/s,0.57m/s and 0.71 m/s,copper recovery rates were 90.56%,85.34%,86.28%,80.33%respectively.The fire experimental results show that:burning can effectively remove organic compounds in the separated material,which produced poisonous gas component in smelting technology:the copper concentrated at the size of 0.42～0.84mm,0.25-0.42mm.In the same heating time(60 min),600℃is the ideal heating temperature;under the same temperature(600℃),materials were fully burned over the time of 40 min.更多还原