10 Questions and Answers to Better Understand Chemical Recycling
1. Is the chemical recycling concept used in the same way globally?
Chemical recycling (also referred to as advanced recycling) fits within national legislations and its definition can differ by geographies, which might have led to some confusions.
The chemical recycling definition in Europe is now clear and alignment has been found across the whole plastic value-chain through the European Coalition on Chemical Recycling*. It follows the existing EU definition of recycling in the Waste Framework Directive which includes chemical recycling under the definition of ‘Recycling’. The use of the output as a fuel in Europe is therefore excluded from the definition of chemical recycling.
This often raises questions around the classification of pyrolysis, whereby differing companies utilising a pyrolysis model may choose to make a fuel (which will not count under ‘recycling’), or sell their outputs as products / raw materials to make new products or plastics (which will count under ‘recycling’). All can have a role to play, but at different levels in the waste hierarchy.
Although there is an alignment in Europe on the definition, EU regulations are independent from regulations or definitions in other regions.
In North America, for instance the term Advanced Recycling or Enhanced Recycling is synonymous to Chemical Recycling, yet there it includes applications for fuels, compared to Europe.
*Chemical Recycling converts polymeric waste by changing its chemical structure to produce substances that are used as products or as raw materials for the manufacturing of products. Products exclude those used as fuels or means to generate energy.
2. How can chemical recycling contribute to the EU Green Deal, EU Circular Economy Package, EU Chemicals Strategy for Sustainability, as well as to the EU economy?
The EU Green Deal sets an ambitious growth roadmap towards a climate-neutral circular economy for the EU by 2050. Chemical recycling can help drive the EU towards a sustainable model by turning waste back into valuable products and thus keeping them in the cycle, by reducing carbon emissions by replacing incineration with chemical recycling process and by decoupling the manufacture of new plastic materials from fossil feedstock. Chemical recycling will effectively help increase recycling rates with the aim, for example, to reach the EU recycling targets for plastic packaging of 50% by 2025 and 55% by 2030.
Furthermore, the EU Chemicals Strategy for Sustainability aims at preventing or minimizing the presence of hazardous substances in recycled materials in order to achieve sustainable and safer circular economy for plastics. Chemical recycling can play a key role in eliminating those chemicals, thus ensuring hazardous-free and safe products that contain recycled materials.
3. What chemical recycling offer that mechanical recycling cannot?
Currently, plastic waste, especially rigid plastics, which are composed of one type of polymer can be recycled through mechanical recycling. In the mechanical recycling process, plastic waste is washed and separated by colour and polymer type and remelted and formed into pellets. These pellets are then made into new plastic products through a process involving melting and moulding. Through the mechanical recycling process, plastics cannot be recycled indefinitely, nor most of the time into the same application as individual plastic characteristics degrade with each melt process.
Chemical recycling addresses the plastic waste that cannot be mechanically recycled for technical or economic reasons. Chemical recycling offers a solution for plastic waste which is either more contaminated, or mixed and/or consist of multi-materials.
Chemical recycling is therefore a complementary solution to sit alongside traditional mechanical recycling, as it can be used to process a wider scope of plastic waste that is currently unsuitable for mechanical recycling. Additionally, chemical recycling overcomes some of the quality challenges faced by mechanical recycling as it can produce the basic chemicals needed to create high-quality food-grade packaging (this quality is currently mainly reached by the mechanical recycling of PET). It therefore overcomes issues related to odour, colour/aspect, limited functionality (in terms of application), and quality of the recycled content. Recycled content from chemical recycling is comparable to virgin materials and is therefore likely to be integrated into food-grade packaging.
Overall, chemical recycling takes a different type of plastic waste as its feedstock and creates a different quality output than that of mechanical recycling and is therefore a complementary recycling solution.
4. Can chemical recycling take all plastic waste?
No. Firstly, some plastic waste already has a clear and economical route to be mechanically recycled. While this plastic waste could be chemically recycled from a technical perspective, this plastic waste has an existing market through mechanical recycling and is preferred from an environmental point of view. Innovation in mechanical recycling processes will continue to improve its performance, yet, for some plastic structures, contamination levels and for some end-market applications, chemical recycling has an important role in filling the gap.
Second, most technologies have specifications for the plastic waste feedstock they process. Although different chemical recycling technologies can complement each other in covering different streams of polymers, they cannot take currently all plastic waste streams on the market that mechanical recycling cannot treat. These specifications are required to ensure the chemical recycling process is economical, achieves the right yield and delivers the targeted environmental performance. Therefore, it is an important aim for the plastic value-chain to continue working on the eco-design of their products to ensure all plastic waste can be either mechanically or chemically recycled, both economically and technically. Improved eco-design is the first step in ensuring that either mechanical or chemical recycling can recycle the plastic item. While fulfilling the necessary properties for the application intended, the plastic product needs to be simplified as much as possible.
Third, chemical recycling can theoretically take plastics from different sectors (for example packaging, automotive, agriculture). So far, focus has been placed on packaging, particularly post-consumer packaging, and due to its short-term use and partial collection. There are opportunities to recycling waste plastic from other sectors, although further studies must be done on the impact of different additives or contaminants on chemical recycling technologies.
5. Why is chemical recycling (only now) a growing sector?
Mechanical recycling has been around for many decades as a part-recycling solution for certain plastic waste streams. Despite chemical recycling technologies being available for some time, it is only in the past 5 years or so that the global plastic waste challenge has been brought to the attention of many parties in an effective way. Consumers, companies, governments and NGOs, amongst others, have realized that a concerted effort, involving the entire plastic value chain, is required to address the issue. Significantly increasing recycling rates of plastic waste are now being put at the top of EU’s and national governments’ agenda. As mechanical recycling has its limitations, some attention has been given to technologies such as chemical recycling, that can provide a new and powerful solution to this challenge.
6. What plastics are being used in the chemical recycling processes? Can bioplastics be chemically recycled?
Plastic waste used in chemical recycling are those streams that are currently not recycled mechanically – for technical or economic reasons – and which would otherwise end up in waste-to-energy, incineration, or landfills, or worse still as plastic pollution in the environment. In this sense, chemical recycling is complementing mechanical recycling efforts by increasing the recycling rates.
Each chemical recycling technology can treat specific feedstock and therefore offer a complementary model to support a circular economy for all plastics.
Deploymerisation mostly focuses on monostreams independently sorted by plastic types: PET (including fibers), PA, PU, PMMA and PLA.
Pyrolysis and hydrothermal upgrading mostly focus on mixed polymers (including multilayers, multi-materials within controlled limits): LDPE, HDPE, PP, PS.
Gasification mostly focuses on mixed polymers.
Bioplastics can be bio-based, like bio-based PE (polyethylene) and bio-based PUR (polyurethanes), biodegradable, for example PBAT (polybutylene adipate terephthalate), or both, such as PLA (polylactic acid) and starch blends.
Bio-based plastics that are chemically and physically identical to their fossil-based counterparts, but made from biomass, like bio-based PE or PET and can be recycled by some chemical recycling processes. However, biodegradable plastics are mostly not recyclable by pyrolysis.
CRE strongly supports efforts to ensure that biodegradable plastics are sorted and diverted towards waste streams for composting or other feasible recycling operations.
7. Is chemical recycling a reality or still a myth on a paper? Are the technologies already optimized?
Compared to what some claim, chemical recycling is now a reality. However, it is not a recycling solution which has been fully scaled yet.
Some chemical recycling plants are already up and running in Europe either as pilot or as small industrial and commercial plants. Additionally, some of their outputs are REACH registered and already sold on a daily basis.
Chemical recyclers have worked with the value-chain to further prove the chemical recycling process by incorporating the high-quality recycled content into brands’ commercialized food-grade products or by making value-added products which are used in existing products, formulations and processes.
Yet, the technologies are in constant evolution. R&D activities have provided new opportunities for optimizing existing processes in the areas of health and safety, environmental, energy, product quality, etc. Following any technology development processes, each chemical recycling process will follow an evolutionary path of development and deployment and significant progress is expected to be achieved in the coming 5 years.
8. What is the yield of the different processes? Are there any by-products of the chemical recycling processes?
For all chemical recycling processes, the yield naturally varies based on the composition and contamination of the plastic waste. Chemical recycling still relies on good sorting system to prepare the plastic waste into a feedstock to the specifications required to make the processes technically and economically viable.
Taking real data based on existing streams the following are indications:
Pyrolysis has a yield ranging around 70-80%.
Hydrothermal upgrading has a yield of around 85%.
Deploymerisation has a yield closer to 90%.
In most chemical recycling technologies, there is some residue which is being used/sold as input into other processes or products like bitumen or in cement.
9. Is the output of chemical recycling suitable for food-contact application?
Yes, it has the capacities and properties, but it doesn’t yet have the full policy recognition. This is something that the chemical recycling sector, through CRE and also directly, is working on with other stakeholders.
Chemical recycling technologies can remove contaminants through purification steps and can create outputs comparable to virgin materials which are therefore suitable for food-contact applications.
Although pyrolysis doesn’t have yet the policy recognition that is currently being discussed in the Commission under DG SANTE, the hydrocarbon oils from this process have received a formal authorization to be used in food-grade packaging. The current assessment of the Commission in the amendment of EU Regulation 282/2008 is that no EFSA authorisation would be necessary for “Feedstock Recycling” due to the eliminated contamination following the chemical recycling and cracking unit.
Deploymerisation does not have the policy recognition either. However, we hope that DG SANTE will authorize the output to be used for food-grade applications without an EFSA authorisation as long as the output is in compliance with the with the defined characteristics and purity levels as explained in Regulation 282/2008/EC and Regulation 10/2011/EC.
10. What is the LCA of various chemical recycling technologies?
We are in the process of developing a holistic chemical recycling LCA, although some of our members already have conducted Life Cycle Analyses for their processes.
Overall, the results of Life Cycle Analysis for chemical recycling processes are positive. Chemical recycling:
has a lower environmental impact than incineration with energy recovery;
has a lower environmental impact than making plastics or specialty chemical products from fossil sources;
tends to have a higher environmental impact than mechanical recycling, although it varies between technologies and plastic streams treated.
Here are some links to the existing LCA results:
CE Delft : https://www.cedelft.eu/assets/upload/file/Presentaties/2019/Chemical%20recycling%20an%20environmental%20perspective%20CE%20Delft%2020%20february%202019%20brussel.pdf
BASF : https://www.basf.com/be/en/who-we-are/sustainability/we-drive-sustainable-solutions/circular-economy/mass-balance-approach/chemcycling/lca-for-chemcycling.html
Some companies have also done their own LCA that you can find on their website.