Extrusion International 5-2023

58 Extrusion International 5/2023 CHEMICAL RECYCLING – INTERVIEW cycling, for example to fuel the pyrolysis process, and if you consider that afterwards you are right back at the beginning of the value chain, namely with syn - thetic crude oil, which then has to be processed again using energy, the claim that chemical recycling does not consume that much more energy than mechani- cal recycling cannot be upheld. Manfred Hackl: An honest process analysis would immediately show quite clearly that the energy input is higher in chemical recycling. Inmechanical recycling, a temperature of 250 degrees is needed for washing and extrusion. After that you have finished regranu - late. In chemical recycling, the energy required for breaking down the raw material into its basic chemi- cal components and then merging the components is many times higher. A lot of research is being done in mechanical recycling to constantly improve recyclate qualities. Won’t the research become obsolete if all the raw materials are broken down into their original components in chemical recycling anyway? Hackl: We don't see it that way at all. In the last few years, a lot has happened in mechanical recycling, also because the entire industry is developing many things jointly. This has made it possible to realise solutions that were unimaginable just a few years ago. The quality of the re-granulate now allows for very demanding ap- plications. In addition, mechanical recycling is already a functioning business model that makes sense ecologi- cally and economically. It is both efficient and scalable. That's why I don't see why the development of me- chanical recycling should rendered obsolete by chemical recycling. We will also see further developments within mechanical recycling. At EREMA, for example, we are opening our new research and development centre for mechanical recycling at our headquarters in Ansfelden in June – a 10 Million-Euro investment. However, chemi - cal recycling has its justification for certain material streams that mechanical recycling is not suitable for. What division of duties would then make sense in the future from your point of view? Lederer: The goal must be for the two technologies to complement each other; and in such a way that chemical recycling processes those materials that cannot be recy- cled mechanically. These are, for example, mixed plastics such as multi-layer films or fibre-reinforced plastics – or also such material that is intended to come into contact with food as an end product later. If chemical recycling manages to process the poorer quality materials and bring them into a cycle, then this would be a valuable addition. The division of duties would then be to avoid waste. If that isn’t possible, mechanical recycling will come in, and only when that reaches its limits will chemi - cal recycling get a chance. This hierarchy makes sense be- cause chemical recycling is more expensive and energy- intensive. At EREMA, we try to support chemical recyclers with our extrusion technology so that they can reliably and energy-efficiently bring potentially difficult-to-han - dle material streams into their chemical recycling process. In this way, we are making an important contribution to developing chemical recycling to the point where it can ultimately be a real complement to mechanical recycling. So EREMA serves both processes with its recycling machines. Where do you see the potentials for each? Hackl: We already offer the entire process technology for the mechanical treatment. Based on the strong in- crease in demand in the last two years, we can see how dynamically mechanical recycling is developing. For the chemical process, we supply a process for me - chanical treatment that is often applied at the beginning of the process chain to prepare input streams for subse- quent chemical recycling processes. We also see a lot of potential in this area and have already received a number of orders. However, numbers are still comparatively small at the moment, because very few large plants for chemi - cal recycling have been completed worldwide so far. In any case, our wish is to raise both potentials. Will the circular economy be accelerated by chemical recycling? Hackl: That will occur in the medium or long term at the earliest, but chemical recycling can already help im - prove the image of plastics today, because it will be the case that eventually, very many types of plastic will be able to be recycled. Thank you for this interview. EREMA Engineering Recycling Maschinen und Anlagen Ges.m.b.H. Unterfeldstraße 3, 4052 Ansfelden, Austria www.erema.com VDMA e.V. Plastics and Rubber Machinery Association Lyoner Str. 18, 60528 Frankfurt amMain, Germany vdma.org/kunststoffmaschinen-gummimaschinen Klaus Lederer Manfred Hackl