Mines Paris, PSL University, Centre for Geosciences and Geoengineering, 77300 Fontainebleau, France.
Chimie ParisTech, PSL University, CNRS, Institut de Recherche de Chimie Paris, 11 Rue Pierre et Marie Curie, 75005 Paris, France.
Waste Manag. 2024 Oct 1;187:296-305. doi: 10.1016/j.wasman.2024.07.001. Epub 2024 Jul 31.
Whether it be to measure their value before a trade, to calculate yields and optimize the recycling process or to check for the presence of harmful substances, Waste Electronic and Electric Equipments (WEEE) need to be characterized. Sampling can give an accurate assessment of the grade of a batch of WEEE, but quantifying the uncertainty around this estimate can be delicate. Pierre Gy's sampling theory of particulate matter studies how the latter is affected by the physical and chemical properties of the studied objects. However, its application requires a deep understanding of the correlations existing between their size, shape, volume, density, mass and grade, which are still unclear for WEEE fragments. Although average information is typically available on batches of WEEE, a more detailed description would be necessary to gain insight into such relationships. To start filling the gap, this paper focuses on the fine characterization of two different batches of waste printed circuit boards, crushed into pieces of about 10 mm. One by one, over 5,000 fragments were sampled, photographed and analyzed. Their individual mass, density, volume, thickness, surface, width and length were all measured separately. Based on their appearance, they were also sorted into four heuristic categories: plastic, metal, circuit boards and electronic components. Descriptive statistics of this novel granulometric database are shown here, throwing light on the unique correlations between the studied parameters and exhibiting a peculiar mass-size law. They point to new avenues on how to adapt Gy's sampling model to WEEE.
无论是在交易前衡量其价值、计算收益率和优化回收过程，还是检查有害物质的存在，都需要对电子废物和电气设备（WEEE）进行特性分析。采样可以对一批 WEEE 的等级进行准确评估，但量化该估计值的不确定性可能很棘手。Pierre Gy 的颗粒物采样理论研究了后者如何受到研究对象的物理和化学特性的影响。然而，其应用需要深入了解 WEEE 碎片之间的大小、形状、体积、密度、质量和等级之间存在的相关性，而这些相关性对于 WEEE 碎片来说仍然不清楚。虽然通常可以获得 WEEE 批次的平均信息，但为了深入了解这些关系，还需要更详细的描述。为了填补这一空白，本文专注于对两个不同批次的废印刷电路板进行精细特性分析，将其粉碎成约 10 毫米的碎片。超过 5000 个碎片被逐个采样、拍照和分析。它们的个体质量、密度、体积、厚度、表面、宽度和长度都分别进行了测量。根据它们的外观，它们还被分为四类启发式类别：塑料、金属、电路板和电子元件。本文展示了这个新颖的粒度数据库的描述性统计数据，揭示了研究参数之间独特的相关性，并表现出一种特殊的质量-尺寸规律。它们为如何适应 Gy 的采样模型以应用于 WEEE 提供了新的途径。
