Extrusion International 3-2021

33 Extrusion International 3/2021 Fraunhofer Institute for Microstructure of Materials and Systems IMWS Walter-Hülse-Str. 1, 06120 Halle (Saale), Germany www.imws.fraunhofer.de Plastics such as polyethylene (PE), polypropylene (PP) or poly- styrene (PS), which are currently produced almost entirely from fossil raw materials, are funda- mental to many everyday prod- ucts and modern technologies. The carbon contained in plastics is an important resource for the chemical industry. If it is possible to better identify such carbon- containing components in waste, to recycle them more effectively, and to use them again to pro- duce high-quality raw materials for industry, the carbon can be kept in the cycle. This not only reduces the need for fossil re- sources, but also pollution with CO 2 emissions and plastic waste. At the same time, the security of supply for industry is improved because an additional source of carbon is tapped. The “Waste4Future” lighthouse project therefore aims to create new opportunities for recycling plastics in order to make the car- bon they contain available as a “green” resource for the chemi- cal industry. “We are thus pav- ing the way for a carbon circular economy in which valuable new basemolecules are obtained from plastic waste and emissions are largely avoided: Today’s waste becomes tomorrow’s resource,” says Dr.-Ing. Sylvia Schattauer, deputy director of the Fraun- hofer Institute for Microstructure of Materials and Systems IMWS, which is heading the project. “With the know-how of the par- ticipating institutes, we want to show how the comprehensive re- cycling of waste containing plas- tics without loss of carbon is pos- sible and ultimately economical through interlocking, networked processes.” The outcome of the project, which will run until the end of 2023, is expected to be in- novative recycling technologies for complex waste that can be used to obtain high-quality recy- clates. Specifically, the development of a holistic, entropy-based assess- ment model is planned (entropy = measure of the disorder of a system), which will reorganize the recycling chain from process- guided tomaterial-guided. Anew type of sorting identifies which materials and in particular which plastic fractions are contained in the waste. Based on this analysis, the total stream is separated and a targeted decision is then made for the resulting sub-streams as to which recycling route is the most technically, ecologically and eco- nomically sensible for this specific waste quantity. What cannot be further utilized by means of me- chanical recycling is available for chemical recycling, always with the aim of preserving the maxi- mum possible amount of carbon compounds. Burning waste con- taining plastics at the end of the chain is thus eliminated. The challenges for research and development are considerable. These include the complex evalu- ation of both input materials and recyclates according to ecologi- cal, economic and technical cri- teria. Mechanical recycling must be optimized, and processes and technologies must be established for the key points in the material utilization of plastic fractions. In addition, suitable sensor technol- ogy must be developed that can reliably identify materials in the sorting system. Machine learning methods will also be used, and the aim is to link them to a digital twin that represents the proper- ties of the processed materials. Another goal of the project is the automated optimization of the formulation development of re- cyclates from different material streams. Last but not least, an economic evaluation of the new recycling process chain will be carried out, for example with re- gard to the effects of rising prices for CO 2 certificates or new regu- latory requirements. The proj- ect consortium will also conduct comprehensive life cycle analysis (LCA) studies for the individual recycling technologies to identi- fy potential environmental risks and opportunities. For the development of the cor- responding solutions, the partici- pating institutes are in close ex- change with companies from the chemical industry and plastics processing, waste management, recycling plant construction and recycling plant operation, in order to consider the needs of industry in a targeted manner and thus increase the chances of rapid application of the results achieved. The following Institutes are in- volved in the Fraunhofer light- house project “Waste4Future”: – Fraunhofer Institute for Micro- structure of Materials and Sys- tems IMWS (lead) – Fraunhofer Institute for Non- Destructive Testing IZFP – Fraunhofer Institute for Materi- als Recycling and Resource Strat- egy IWKS – Fraunhofer Institute of Optron- ics, System Technologies and Im- age Exploitation IOSB – Fraunhofer Institute for High Frequency Physics and Radar Techniques FHR – Fraunhofer Institute for Struc- tural Durability and System Reli- ability LBF – Fraunhofer Institute for Process Engineering and Packaging IVV