Rao Mudila Dhanunjaya, Meshram Rohit B, Singh Kamalesh K, Morrison Carole A, Love Jason B
CSIR-National Metallurgical Laboratory, Jamshedpur 831007, India; Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India.
CSIR-National Metallurgical Laboratory, Jamshedpur 831007, India.
Waste Manag. 2023 Oct 12;171:621-627. doi: 10.1016/j.wasman.2023.10.008.
Informal recycling activities of waste printed circuit boards, such as pyrolysis and landfilling, cause severe environmental harm to society. Pyrolysis of resin and polymer fraction leads to the generation of toxic effluents, and landfilling causes the leaching of heavy metals into the groundwater. A sustainable and eco-friendly way to recover base and precious elements will be an economically attractive option. Current research studied the cradle-to-gate environmental impacts of the sequential recovery of copper and gold through delamination, leaching, solvent extraction, electrowinning and cementation from waste printed circuit boards with the help of life cycle assessment.GaBi software was utilized to assess environmental impacts such as global warming, abiotic depletion (fossil), acidification potential and human toxicity potential during the process. Inventory data was collected by conducting several experiments and from optimizing parameters for recycling and separating 4.53 g of copper and 2.25 mg of gold from 16 g of component-free waste printed circuit boards. Results indicate that the chemical pre-treatment or delamination process for separating metal clads from the non-metallic fraction is primarily involved in the impact category. The higher impact during delamination is due to electricity consumption. The proposed study also corroborates the industrial viability of recycling valuable metals from waste printed circuit boards to minimize the environmental impacts. The outcomes of this work could be beneficial in creating the environmental guiding principle for WPCBs recycling plants.
废旧印刷电路板的非正规回收活动，如热解和填埋，会对社会造成严重的环境危害。树脂和聚合物部分的热解会产生有毒废水，而填埋会导致重金属渗入地下水。一种可持续且环保的回收贱金属和贵金属的方法将是一个具有经济吸引力的选择。当前的研究借助生命周期评估，研究了通过分层、浸出、溶剂萃取、电解沉积和置换从废旧印刷电路板中顺序回收铜和金的从摇篮到大门的环境影响。利用GaBi软件评估该过程中的全球变暖、非生物资源耗竭（化石）、酸化潜势和人体毒性潜势等环境影响。通过进行多项实验并优化从16克无组件废旧印刷电路板中回收和分离4.53克铜和2.25毫克金的参数来收集清单数据。结果表明，从非金属部分分离金属包层的化学预处理或分层过程主要涉及影响类别。分层过程中影响较大是由于电力消耗。该研究还证实了从废旧印刷电路板中回收有价金属以尽量减少环境影响的工业可行性。这项工作的成果可能有助于为废旧印刷电路板回收厂制定环境指导原则。
