This Way2K interview conducted by the VDMA in the lead-up to K 2022 with Dr. Stephan Gneuß, Managing Director of Gneuss Kunststofftechnik GmbH explores the challenges of plastics recycling and the different responses. “At the moment we often recycle at any cost. ”
Dr. Gneuß, how has recycling developed in recent years?
From the supplier side, recycling in general and also up-cycling in many cases was already possible a few years ago, as was visible at K 2019. However, back then far fewer customers were interested in it than today. I haven’t seen a fundamental technological breakthrough since then, but there have been many steady improvements. In the meantime, interest in recycling has grown considerably. The reason is the pressure from consumers and the political arena. Our company Gneuss therefore now has a great number of projects for up-cycling and very high quality recycling. This is a very positive development where we can play to the strengths of our products very well.
Could you give an example?
Our recycling machines and lines are all designed to achieve both very high quality and consistency within the relevant processes. In the extrusion sector, we have paid great attention to food contact capability from the very beginning. This is precisely what many now place at the top of the agenda. Our continuous filtration systems also play a key role in recycling, because with the increasing use of recyclates, filter elements are being changed much more frequently, which is where a pressure-constant and continuous mode of operation is essential. Today, we offer turnkey systems for recycling, not only for polyester, but also for polystyrene, polypropylene and polyolefins, and others.
Is it possible to compensate for quality fluctuations in the material with improved extrusion technology?
Yes, definitely. That is one of the core tasks for the recycling equipment; it has to cope with different input qualities, but in the end, it is the purity of the type that determines which qualities will emerge. If you’re now wondering whether improved extrusion technology makes separation by type unnecessary, the answer is no – because, if you mix different types of plastic during melting, you always suffer a loss in quality.
Is recycling also worthwhile from an economic perspective?
At the moment, in some segments, we see recycling at all costs. There is simply pressure to use recycled materials because otherwise you can no longer sell your products. Where these processes are more established, economic efficiency naturally gains priority. We will see significant progress here in the next few years. This increasing focus on economic efficiency is a development that definitely plays into our hands as a company.
We still have a quantity problem. How can the shortage be eliminated?
The quantity problem is indeed crucial: it is largely determined by product design and waste collection. If you want to solve the problem, you have to intervene very early in the process. There are already approaches to solving the problem, for example, more mono-materials or more deposit systems. Our task will be to provide the technical prerequisites for new recycling cycles; something that we can handle. The bottleneck is collection and product design. Something will have to be done about this, because otherwise the circular economy will not work and we as the plastics industry will never get rid of its bad reputation.
There are two points of criticism about plastic: one is the CO2 balance, which is burdened among other things by recycling quotas that are too low. The other is the littering of the landscape and the oceans. This is also a major problem, but it is only secondarily related to recycling, as it is primarily a disposal and collection problem. However, we cannot turn away from the problem. At the moment, politically, we see considerable pressure on plastic products, especially in Europe and North America. Recycling quotas and targets are actually the easier way to go. France, for example, has relatively low collection rates, but an increasing tendency to ban plastic products. This however is often the worst solution because the alternative materials are rarely better in terms of sustainability and carbon footprint. We have to take care of both: do something about littering and improve the carbon footprint. Both must be taken into account during product design.
Do you also need regulations for product design?
Partly, yes, but I think it is too complex for general legal regulations for product design. I also fear that we are running out of time if we wait for comprehensive specifications. This discussion has been going on for a long time, but it is still the case that recyclability comes last in the development process for many products. It's easy to write on a package that it contains recycled material. What exactly is recycled, how much and how, and whether it makes sense, is another matter altogether. There is still a lot of work ahead of us.
Where will we be three years from now?
I see the pressure increasing and this will lead to changes; not only in the packaging sector, which is primarily responsible for the littering of the oceans, but a rising amount of plastic is also being used for clothing, and these clothes are being disposed of at an increasingly fast rate. I assume that we will already see changes at K 2025, such as a rethink in product design, better collection systems, and therefore better flows of goods. Accordingly, the demands on plant and machinery manufacturers will be different, but we are used to conditions changing, and we simply have to adapt.