Short wave infrared hyperspectral imaging for recovered post-consumer single and mixed polymers characterization

Abstract

Postconsumer plastics from packing and packaging represent about the 60% of the total plastic wastes (i.e. 23 million of tons) produced in Europe. The EU Directive (2014/12/EC) fixes as target that the 60%, by weight, of packaging waste has to be recovered, or thermally valorized. When recovered, the same directive established that packaging waste has to be recycled in a percentage ranging between 55% (minimum) and 60% (maximum). The non-respect of these rules can produce that large quantities of end-of-life plastic products, specifically those utilized for packaging, are disposed-off, with a strong environmental impact. The application of recycling strategies, finalized to polymer recovery, can represent an opportunity to reduce: i) not renewable raw materials (i.e. oil) utilization, ii) carbon dioxide emissions and iii) amount of plastic waste disposed-off. Aim of this work was to perform a full characterization of different end-of-life polymers based products, constituted not only by single polymers but also of mixtures, in order to realize their identification for quality control and/or certification assessment. The study was specifically addressed to characterize the different recovered products as resulting from a recycling plant where classical processing flow-sheets, based on milling, classification and separation, are applied. To reach this goal, an innovative sensing technique, based on the utilization of a HyperSpectral Imaging (HSI) device working in the SWIR region (1000-2500 nm), was investigated. Following this strategy, single polymers and/or mixed polymers recovered were correctly recognized. The main advantage of the proposed approach is linked to the possibility to perform "on-line" analyses, that is directly on the different material flow streams, as resulting from processing, without any physical sampling and classical laboratory "off-line" determination

Near infrared spectroscopy as a tool for in vivo analysis of human muscles

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Hyperspectral Imaging Applied to WEEE Plastic Recycling: A Methodological Approach

“…HSI is a cutting-edge approach to waste management that is rapidly gaining popularity as a quality control tool and as a core for sorting engines in several recycling processes [9]. Different HSI-based approaches have been proposed for plastic recycling [10][11][12], Construction and Demolition Waste (C&DW) recycling [13,14] and WEEE recycling [15,16].…”

Hierarchical modelling for recycling-oriented classification of shredded spent flat monitor products based on HyperSpectral Imaging

“…In recent years, the use of NIR-HSI has grown rapidly in many sectors, including the solid waste sector . In literature, different HSI-based approaches are proposed for plastic recycling (Ulrici et al, 2013;Bonifazi et al, 2015), construction and demolition waste recycling (Palmieri et al, 2014;Serranti et al, 2015;Bonifazi et al, 2015;Bonifazi et al, 2017;Bonifazi et al, 2018c) and WEEE recycling (Palmieri et al, 2014;Bonifazi et al 2018b).…”