Transparency in the life cycle assessment: What is the environmental impact of recycled plastics?

There is a growing demand for information on the environmental impact of the use of recycled plastic. However, publications and reliable data are rare. Now is the time for industry, academia and policy makers to share ideas and reach a consensus on how to model the environmental impact of recycled plastics. This is exactly where the Fraunhofer CCPE compact on 20 June 2024 on "Impacts of recycled plastics – A stakeholder approach to find consensus in LCA" comes in. Dr Anna Kerps and Tanja Fell give us an initial insight in this interview.

May 14, 2024, 5:11:21 PM
Dipl.-Chem. Iris Kumpmann, Fraunhofer-Institut für Umwelt-, Sicherheits- und Energietechnik UMSICHT

Anna, you are the lead author of the position paper ‘Challenges and requirements in comparative life cycle assessment of plastics recycling’ published by Fraunhofer CCPE in January 2024. What is the most important message for you in this paper? Anna Kerps: We - and by that I mean research and industry in particular - still have a long way to go before we can make reliable statements about the comparative environmental impact of recycled plastics. There is currently a lack of standardised and harmonised rules for LCA studies in the field of plastics recycling, which can lead to misleading communication and decision-making. In the position paper, we have formulated ten challenges and ten requirements relating to the comparability of different studies in the field of plastics recycling. We are currently working on addressing some of these challenges using solvent-based recycling as an example, which we are developing further in the CCPE cluster and beyond. We want to make the differences and incomparabilities visible through modelling decisions using the example of solvent-based recycling. New recycling technologies in particular have different requirements for system boundaries and modelling decisions. In order to be able to show the environmental benefits of recycled plastics in comparison with each other and with virgin plastics, it is necessary to create a standardised assessment framework for the life cycle assessment so that the raw material types can be compared with each other. How is your recycling technology, solvent-based recycling, already contributing to this? Tanja Fell: We keep plastic resources from waste that is otherwise considered non-recyclable in the cycle, i.e. we come from heavily contaminated post-consumer film packaging waste, for example, and can reintroduce our recyclates into a film application for packaging. We achieve the high recyclate quality required for this through the high selectivity of our dissolving process and our effective cleaning methods. The process requires less energy than virgin material production and chemical recycling; in short, we achieve high qualities and a positive ecological balance through the process. The process should not be seen as a competitor to thermo-mechanical recycling, but rather as a complementary physical recycling route. This is because the solvent-based process is primarily aimed at heterogeneous waste materials that have so far either only been thermally utilised or can only be processed into very low-grade recyclates. After the Fraunhofer CCPE compact, you will ask the industrial companies for interviews. What will that be about? Anna Kerps: Exactly! We want to enter into a dialogue with plastics recyclers in order to compare the theoretical challenges from the position paper with the practical benefits and costs of recycling. The aim is to better understand the challenges and discuss them together in a stakeholder approach. Modelling decisions in life cycle assessment are generally characterised by different motivations, objectives, topicality and underlying (scientific) expertise as well as the potential fields of application for plastics. On the one hand, we want to impart knowledge and enter into a dialogue; on the other hand, the aim is to create a consensus. Many individual studies on plastics recycling independently show that the use of recyclate leads to environmental benefits compared to virgin material. So far, however, these studies cannot be compared with each other. Together with industrial companies, we would like to strengthen the use of recyclates through comparable modelling decisions. What is important for you to tell the industry about the life cycle assessment of recycled plastic? Anna Kerps: It is unacceptable for recyclates to bear a large proportion of the burden of emissions from the downstream incineration of collected contaminants. As recycling is a multi-functional process and waste is utilised and new material is produced at the same time, the environmental impact of collection, sorting and recycling should be allocated according to the function of waste utilisation and resource provision. We would like to solve this multifunctionality problem together. The starting point for this exchange is the upcoming online event, where we will revisit the challenges and then enter into dialogue together. We would like as many people as possible to take part in order to achieve a high level of support. You can register free of charge for the online event Fraunhofer CCPE compact ‘Impacts of recycled plastics - A stakeholder approach to finding consensus in LCA’ on 20 June 2024 from 14:00 to 16:00 here. The event will be held online in English.