Plastic waste from recycling centres: Characterisation and evaluation of plastic recyclability

While recycling has been recognised as the preferred plastic waste management solution, little is known about the detailed characteristics of plastic waste and how these may affect its recycling. In this study hard plastic, plastic film and PVC waste collected at three Danish recycling centres were sampled and characterised according to product applications, legislative requirements (quality), expected product life time, polymer types and presence of potential impurities such as coloured plastics, non-plastic materials and multi-polymer products.

The obtained information was applied for estimation of overall recycling potentials for selected archetype recycling process chains based on material flow analysis. In addition to providing detailed data for the composition of the plastic waste products, the results showed that impurities represented 28% (wet weight) of the plastic waste, and that about 75% of the plastic waste was characterised as Low Quality applications, indicating some legislative recovery restrictions.

By accounting for the level/type of impurities, the overall recycling potential was found to be 52% for hard plastics, 59% for plastic films and 79% for PVC waste. The results showed that while varying according to polymer type, the recyclability of “High Quality” plastic waste was 12–35% higher than “Low Quality” applications.

While actual results are representative of Danish conditions, the study demonstrates that detailed characteristics of plastic waste are needed to identify potential challenges to recycling and thereby potentially improving the design (and recovery efficiency) of recycling facilities.