The Robert M. Buchan Department of Mining, Queen's University, Kingston, ON, K7L 3N6, Canada.
Department of Chemical Engineering, Monash University, Clayton, Victoria, 3800, Australia; Institute for Frontier Materials, Deakin University, Geelong, Victoria 3200, Australia.
J Environ Manage. 2022 Aug 15;316:115242. doi: 10.1016/j.jenvman.2022.115242. Epub 2022 May 16.
Over the last few decades, a substantial amount of e-waste including waste printed circuit boards (WPCBs) has been produced and is accumulating worldwide. More recently, the rate of production has increased significantly, and this trend has raised some serious concerns regarding the need to develop viable recycling methods. The presence of other materials in the WPCBs, such as ceramics and polymers, and the multi-metal nature of WPCBs all contribute to the increased complexity of any recycling process. Among the viable techniques, pyrometallurgy, with the inherent ability to process the waste independent of its composition, is a promising candidate for both rapid and large-scale treatment. In the present study, firstly, the principles of the pyrometallurgical methods for WPCB recycling are discussed. Secondly, the different unit operations of thermochemical pretreatment including incineration, pyrolysis, and molten salt processing are reviewed. Thirdly, the smelting processes for the recovery of metals from WPCBs, as well as the issues surrounding slag formation and subsequent treatment are explained. Fourthly, alternative methods for the recovery of polymers and ceramics, in addition to metal recycling, are elucidated. Fifthly, emission control techniques and the potential for energy recovery are evaluated.
在过去几十年中，全球产生并积累了大量的电子废物，包括废弃印刷电路板（WPCB）。最近，电子废物的产生速度显著加快，这一趋势引发了人们对开发可行的回收方法的严重关注。WPCB 中存在其他材料，如陶瓷和聚合物，以及多金属性质，都增加了任何回收过程的复杂性。在可行的技术中，冶金学具有独立于组成处理废物的固有能力，是快速和大规模处理的有前途的候选技术。在本研究中，首先讨论了 WPCB 回收的冶金方法的原理。其次，综述了热化学预处理的不同单元操作，包括焚烧、热解和熔盐处理。第三，解释了从 WPCB 中回收金属的熔炼过程，以及围绕炉渣形成和后续处理的问题。第四，阐述了除金属回收外，回收聚合物和陶瓷的替代方法。第五，评估了排放控制技术和能量回收的潜力。
