Guest Interview: Bianca Gubi – Product Manager Circular Economy at ENGEL Austria GmbH “Plastic waste is a valuable raw material. If we manage to keep it in circulation, we can protect our environment and our climate.”

Hello everyone and welcome to this guest interview. Today I present to you Bianca Gubi who is product manager Circular Economy at Austrian injection moulding and automation manufacturer ENGEL AUSTRIA GmbH. We have the chance to deep-dive into Circular Economy moulding, learn about the newly developed two-stage moulding process for recycled materials, and what to take care in design for recycling in injection moulding.

Enjoy the interview!

Guest Interview with Bianca Gubi, working as Product Manager Circular Economy at ENGEL Austria GmbH.  

1. Tell us about yourself, your current role, and your way into the Circular Economy and recycling.

I have been working intensively on the subject of the circular economy for five years now because it's also very important to me personally. Plastic waste is a valuable raw material. If we manage to keep it in circulation, we can protect our environment and our climate. As product manager for Circular Economy at ENGEL, I'm happy to be able to make an active contribution now. That’s something I really like about my work. Here in the Circular Economy Division, we focus on sustainable technologies and are committed to ensuring that recycled plastic waste can be reprocessed to create high-quality plastic products. As an injection moulding machine manufacturer, ENGEL is part of the plastics industry and takes its responsibility very seriously. We are continuously enhancing our machines and have a range of new technologies for the circular economy in our portfolio. As a product manager, I am responsible for the design and marketing of this technology portfolio. That means I analyse what our customers need and collaborate very closely with R&D to meet those requirements. 

2. What are the differences between regular injection moulding and Circular Economy moulding? And are there things which need to be handled with special attention?

For the injection moulding machine, it's more or less irrelevant whether you process granulate, that is, virgin material, or a regranulate, that is, recycled material. This is basically good news if you're looking to establish a circular economy, because it means that it's very easy to switch to regranulate in many applications. But two things, above all, are important if you want to achieve high product quality across the board. Firstly, the plasticising unit needs to be precisely matched to the properties of the material you want to process. ENGEL has a great deal of in-house plasticising expertise and produces all the plasticising units itself; this means that we can offer our customers fantastic support here. Secondly, when you are processing recycled material, you have to take into account that the material is exposed to more pronounced batch fluctuations than you are accustomed to from virgin material. We meet this challenge with smart assistance. For example, the iQ weight control smart assistance system can automatically adjust the injection moulding parameters responsible for quality to match the current conditions for each individual cycle and ensure consistently high component quality by doing so. For standard injection moulding, it is important for the regranulate to be single grade and free of impurities. And if there are impurities, our Circular Technology engineering helps to produce good parts anyway – with our new two-stage process for example. 

3. Can you tell us about the newly developed two-stage moulding process for recycled materials? And can you point to some of the benefits of processing flakes directly compared with ready-to-use recycled pellets? 

Thanks to the new two-stage process, ENGEL makes it possible to process plastic waste as flakes in injection moulding directly after grinding. Since this eliminates pelletising, as a separate and particularly energy-intensive, process step, this innovation significantly improves energy- and cost-efficiency in plastics recycling.

To be able to process flakes in injection moulding, we have broken down plasticising and injection into two independent, but mutually tuned, process steps. In the first stage, the raw material, for example plastic flakes originating from post-consumer or post-industrial collection, is melted in a conventional plasticising screw. The melt is transferred to a second plasticising unit for injection into the cavity. Depending on the material and application, a melt filter and a degassing unit can be integrated between the plasticising and injection units; this allows customers to create high-quality products from contaminated plastic waste. 

The two-stage process is far leaner than the legacy recycling process, where plastic waste is ground, compounded, filtered and pelletised after sorting and cleaning. Thus far, the plastic has had to be melted twice for reprocessing. Pelletising the recycled material is an energy-intensive process which typically also involves logistics overhead. The need for this step is removed completely in the two-stage process. Based on calculations by ENGEL, the energy required for manufacturing the product is reduced by at least 30 percent.

4. How do you see “Design for Recycling” in injection moulding? And what are the upcoming trends in sustainability for plastics moulding?

Design for Recycling is an absolute must-have, if we are serious about the circular economy. Later recycling needs to be taken into account and planned for as early as in the development of new products. One example is thin-wall packaging produced using in-mould labelling. The trend here is towards monomaterial solutions, which allow the containers to be recycled along with the label. Another field where a great deal is happening in terms of design for recycling is lightweight construction in the mobility sector. At ENGEL, we are focusing on thermoplastic composite solutions. In the ENGEL organomelt process, thermoplastic sheets or UD-tapes are formed and functionalised in an integrated process by moulding the functional elements directly onto the preform. Again, the aim is to use materials belonging to the material group of the fibre composite prepreg matrix material for moulding on. The parts created in this way can then be fed back into the material cycle at the end of their service lives.

When it comes to trends for greater sustainability in injection moulding processing, ENGEL is taking action at various levels. Among other things, this is about innovative technologies for processing recycled materials, about process stability thanks to smart assistance systems, but also about the energy efficiency of the processing machines. 

5. Where can the readers find out more about you and the Circular Economy offers?

Just contact me and my colleagues. We are on site at very many trade fairs worldwide and can be contacted at any time by phone, email or on LinkedIn. Our website also gives people great overview of our commitment to sustainability at ENGEL: ▷ Circular Economy & Plastics Recycling - ENGEL (engelglobal.com). We also have our own blog there to keep our readers up to date at all times.

That was the guest interview with Bianca Gubi from ENGEL AUSTRIA GmbH – thank you Bianca and the whole team for sharing such interesting insights of the Circular Economy moulding!

Thanks for reading!

Greetings and #findoutaboutplastics

Herwig Juster