Interview with Sven Engelmann, Head of Packaging Technology at ILLIG Maschinenbau GmbH & Co. KG
Recycling of glass is often more energy-intensive than that of plastics
Chemical recycling is possibly a further option
Thermoformed packaging is lighter than injection-moulded packaging
What does circular economy mean to ILLIG?
Sven Engelmann: To us, circular economy is important because we can provide our customers with sustainable solutions, something our society is asking for. Currently, the opinion prevails that circular economy is a solution for sustainability. Circular economy produces recyclates. As machine and tooling system providers, we adjust the thermoforming processes of our systems in such a way that the recycled plastics can be machined into high-quality mouldings. This has already been done in practise for several decades. Many of our customers use recyclates, however only industrially collected plastic waste resulting from production. Thermoforming systems should be able to offset the variations in quality that always occur when using recyclates. Now we are moving one step further, planning to intensify converting post-consumer waste into recyclates.
Using post-consumer waste is more problematic, isn't it?
Sven Engelmann: Yes, greater effort is required. You need more complex sorting systems, and washing plants to remove the dirt. In material-based recycling of plastics, you try to separate different plastic materials in advance. Usable plastics from the post-consumer waste streams are currently mainly polypropylene and PET. They must be sorted more accurately. Just sorting out PET does not result in uniform PET but in a mix of various PET applications. We are also not sure, whether material-based recycling is a solution in the medium-term future. The ultimate solution might be chemical recycling. For example, these methods of depolymerisation break down a thermoplastic polymer into its individual components, monomers. They are then put together again and polymerised into new plastics. In a sense, this leads to completely new materials. At the K, virgin material manufacturers might present first concepts.
How willing are customers to use recyclates?
Sven Engelmann: The willingness is great. Previously, our customers used recyclates in suitable applications to save costs. And our machines offset possible batch variations. Now we argue that using recyclates enables the production of more sustainable packaging. Customers eagerly accept this. Regarding machines nothing much has changed.
Material-based recycling utilises many resources, critics sometimes say.
Sven Engelmann: Yes, it is true that a lot of energy is required. You must look at the extent and the environmental footprint of the individual packaging materials. Thus, circular economy of plastics requires much less energy than, for example, that for glass or metal. To reuse a yoghurt glass, resource costs are much higher than those of a thermoformed plastic cup.
Many manufacturers of consumer goods want to reduce the share of plastics in packaging. Is that possible?
Sven Engelmann: Yes, that is possible. This trend has clearly accelerated, particularly in the past months. You can already achieve a reduction target of 20 to 25 per cent if you change from injection moulding to thermoforming. This will work with many types of packaging. The result will be lighter, but the mechanical properties are the same. More and more packaging manufacturers therefore change over to thermoformed packaging wherever possible. For example, a margarine tub can be perfectly thermoformed, but very often it is still injection moulded.
How do you reduce the weight?
Sven Engelmann: In thermoforming we start from a semi-finished product, the plastic film, which is transformed. Transforming is achieved by stretching. This has the effect that their mechanical properties are improved because the original material, for example PP, has longer molecule chains. This results in greater strength.
Is there also a trend towards less packaging?
Sven Engelmann: We must consider the purpose of packaging. It must offer protection, secure transportation, ensure hygiene, it has barrier properties to extend durability – it must offer an incentive to buy at the point of sale. Currently, people tend to ignore the latter. But the incentive to buy is still extremely important. Consumers do not buy anything that is not optically appealing. I cannot think of a lot of packaging that uses an absurd amount of material. For this reason, we expect that plastics packaging will continue to exist. Besides, this is not the first crisis the plastics sector undergoes; twenty years ago, there had already been an intensive discussion on this issue. In the end, the realisation prevailed that plastics has many advantages.
What is the most important condition for a functioning circular economy?
Sven Engelmann: We just need more information. Most of the young people who demonstrate for climate protection are not able to take the metal lids off a yoghurt tub and sort them separately. Circular economy can only be successful if consumers make their contribution. They must be informed on how to sort their packaging waste.