Quality assessment of mixed plastic flakes from Waste Electrical and Electronic Equipment (WEEE) by spectroscopic techniques

Abstract

The quality of mechanically recycled plastics from WEEE is seen as one of the main bottlenecks for their re-application in high-quality products to enable a circular economy for these materials. Most literature focuses on the quality at the end of the value chain while significant potential to improve the performance of the entire value chain is seen by the quality assessment of input material of recyclers. In this research a testing procedure for mixed plastic flakes by Fourier-Transform InfraRed (FTIR) spectroscopy, X-Ray Fluorescence (XRF) and manual composition analysis assisted by computer vision. Mixed plastics from TV housings, washing machines, fridges and fridge drawers were taken as case studies. It is shown that unwanted plastic types, glass, metals, wood, rubber and foam as well as additives such as talc, calcium carbonate or brominated flame retardants can be detected by the procedure. In addition, a Failure Mode and Effect Analysis (FMEA) is shown to be a powerful tool for a risk-based assessment of the most relevant quality influences, which allows to define strategies for quality control. The economic evaluation showed that automation is required to allow the systematic use of the testing procedure.

Life Cycle Assessment of a Plastic Part Injected with Recycled Polypropylene: A Comparison with Alternative Virgin Materials

“…The materials obtained by separation in specialized centers are considered to be of better quality and purity than those extracted in the separation of domestic waste [62]. But even so, they are unreliable as they can be subject to human error or cross-contamination [63]. The common agreement is that this is still a field with significant room for improvement [64].…”

Influence of selected contaminations and melt filtration on the properties of ABS and ABS recyclate

“…This Waste Electrical & Electronic Equipment (WEEE) is not only a rapidly growing waste stream, but also a complex one due to various factors. [9][10][11] WEEE includes a large group of waste: small consumer products like mobile phones or laptops, as well as large household devices like fridges or washing machines. Besides various types of plastics, these products contain a large proportion of nonplastic materials, like glass, iron, copper, aluminum, and others.…”

“…Commercial post‐consumer polyolefin recyclates were found to be contaminated with foreign particles, even though most of them were designated as “melt‐filtrated.” 8 One source of waste coming from many diverse applications is post‐consumer waste from electrical and electronic devices. This Waste Electrical & Electronic Equipment (WEEE) is not only a rapidly growing waste stream, but also a complex one due to various factors 9–11 . WEEE includes a large group of waste: small consumer products like mobile phones or laptops, as well as large household devices like fridges or washing machines.…”