Institute for Resources, Environmental and Ecology, Tianjin Academy of Social Sciences, Tianjin 300191, People's Republic of China.
College of Environmental Science and Engineering, Nankai University, Tianjin 300350, People's Republic of China.
Waste Manag. 2020 Jun 15;111:41-50. doi: 10.1016/j.wasman.2020.05.017. Epub 2020 May 25.
Waste mobile phones contain significant amounts of valuable metals and non-metallic materials. Consequently, the extraction of valuable materials from discarded phones, which is a more cost-effective method compared with primary mining, is an essential step for maximizing the recovery of secondary resources and minimizing e-waste pollution. We designed a green and efficient path for recovering valuable metals from waste mobile phones and explored its technical feasibility from both environmental and economic perspectives through life cycle assessment and revenue expenditure model. The results showed that the hydrometallurgical process had three characteristics of high recovery efficiency, significant environmental friendliness and economic feasibility. The recovery efficiencies of valuable metals were higher than 90%. Simultaneously, the return on investment was 29%, indicating that the recycling enterprises can achieve self-sufficiency. Thirdly, the environmental benefits were more significant compared to environmental damage released by hydrometallurgical process, representing a significant environmental friendliness. Within the overall recycling process, the core process made the greatest contribution to the environmental burden (45.38-65.68%), followed by manual disassembly process. A comparison of sub-processes in core process revealed that the mechanical crushing and sorting phase had the greatest environmental impacts that were primarily attributed to power consumption. Consequently, future research should focus on the development of energy-efficient pretreatment techniques and energy-saving equipment. The industrial practice of recycling waste mobile phones is still in its infancy in China. Future studies should also focus on the comparing different treatment processes, with the aim of providing technical support for the advancement of industry.
废旧手机中含有大量有价值的金属和非金属材料。因此，从废弃手机中提取有价值的材料，相比于原始开采，是最大限度地回收二次资源和最小化电子废物污染的关键步骤。我们设计了一条从废旧手机中回收有价值金属的绿色高效路径，并从环境和经济角度通过生命周期评估和收益支出模型探索了其技术可行性。结果表明，湿法冶金工艺具有高回收效率、显著的环境友好性和经济可行性等三个特点。有价值金属的回收率均高于 90%。同时，投资回报率为 29%，表明回收企业可以实现自给自足。第三，与湿法冶金工艺释放的环境损害相比，其环境效益更为显著，具有显著的环境友好性。在整个回收过程中，核心工艺对环境负担的贡献最大（45.38-65.68%），其次是手动拆解工艺。核心工艺中各子工艺的比较表明，机械破碎和分类阶段的环境影响最大，主要归因于电力消耗。因此，未来的研究应集中于开发节能预处理技术和节能设备。中国的废旧手机回收工业实践仍处于起步阶段。未来的研究还应侧重于比较不同的处理工艺，为行业的发展提供技术支持。
