Preparing WEEE plastics for recycling – How optimal particle sizes in pre-processing can improve the separation efficiency of high quality plastics

Review on the photonic techniques suitable for automatic monitoring of the composition of multi-materials wastes in view of their posterior recycling

“…If spectroscopy is applied in automated sorting, separation is performed by air nozzles that blow-out particles from the feed stream, which has previously been subjected to size reduction processes. As recently reported (Maisel et al, 2020), the particle size of such processes is decisive for the sorting outcome. Nevertheless, failures in automated sorting may occur by incorrect identification but also if the air nozzle emits more than the targeted items or if a blownout particle hits another one, which is then falsely separated.…”

“…of the feed is rejected with only 3–4% of the material being off-specification. Another issue of the position in the value chain is the particle size, especially if photonic sorting is combined with other processes such as density separation or washing procedures ( Maisel et al, 2020 ).…”

“…With respect to packaging, this is mainly achieved by rotating sieves and wind sifters defining an input particle size between 3 mm and 20 cm by 30 cm items. With respect to WEEE and ELV plastics deliberated from other materials by shredders and supplied to sorting machines as a shred, typical sizes below 5–50 mm, and preferably between 10 and 20 mm are obtained ( Maisel et al, 2020 ).…”

Ecotoxicity of Plastics from Informal Waste Electric and Electronic Treatment and Recycling

“…The use of FRs with a low environmental load is an effective solution [ 45 ], keeping in mind that FRs cannot be simply interchanged, as most FRs are compatible with only a limited amount of polymers [ 58 ]. However, since the end-of-life phase has the largest environmental load, future improvements are expected, such as investigations of alternative recycling and re-use possibilities and studies on disassembly (and consequently assembly) techniques [ 30 ] that lead to decreases in the amount of e-plastic scraps [ 80 ] and allow for effective recycling and remanufacturing strategies.…”

“…When a large mix of materials has to be reprocessed, dismantling-based recycling (i.e., the disassembly of plastic components before shredding) is the most effective method for recovering high-quality post-consumer plastics (primary recycling) [ 29 ]. Using optimized strategies allows for the separation of plastics so that different materials can be recycled individually [ 1 , 30 ] and the presence of hazardous substances can be measured [ 31 , 32 ] for use as secondary raw for chemical recycling [ 27 ].…”