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Driving Sustainable Futures

August 13, 2021

Watch the Video: Using Mass Balance to Validate Sustainability Claims

An interview by Tim Sykes, Brand Director, Packaging Europe with Luc Bosiers, Senior Development Engineer, Trinseo.

Click below to watch the video or read the transcript of the discussion that follows.

video preview

Tim Sykes (00:11):

In our sustainability perspective series complementing the Sustainability Awards 2021 and the Sustainable Packaging Summit, we're sharing interviews with thought leaders from across the packaging value chain and exploring the key areas of progress. In this video, we're looking at the way mass balance accounting can be used to support transparent reincorporation of recycled material back into the start of the loop. And I'm very grateful to be joined today by Trinseo's senior development engineer, Luc Bosiers, who can talk us through the concept and explain how Trinseo is utilizing mass balance certification to underpin its own circular economy strategies. Luc, thank you for joining me today. I'd like to start by taking a moment to ensure that we understand the basics of what we're talking about. For those who aren't familiar with the concept, what's behind the idea of mass balance.

Luc Bosiers (01:09):

Well, mass balance for sustainable plastics is a methodology that's used to track sustainable content through the value chain. It allows a manufacturer and all the parties along the value chain to know precisely the total amount of sustainable content in a finished or semi-finished product. The concept is about mixing traditional and alternative products. In this case, the alternative product is the sustainable plastic raw material. And at the same time, keeping track of their quantities and allocating them to specific products. In every step of the process, the amount of sustainable content can be declared in accordance with the mass balance process that was validated by an independent and internationally recognized auditor. The mass balance methodology isn't new. It's well accepted in many industries, for example, green electricity, wood, paper, vegetable oil, cotton, and practically any industry where it might be necessary to commingle raw materials, when those raw materials are actually indistinguishable.

Luc Bosiers (02:15):

The chemical industry adopted the concepts to track bio sourced or post-consumer recycled raw materials in plastic products. Let's take green electricity as an example. A person contracting for 100% green electricity will not receive 100% green electricity every hour of every day as the electricity provider mixes electricity derived from nuclear, fossil and green sources on the grid. However, the provider can in total only sell as much green electricity as he bought or produced and this is tracked and audited. It has become a well-accepted practice globally, that is stimulating the transition towards an all green electricity without a need to build segregated power grids, exclusively reserved for green electricity. And the analogy doesn't stop here, once produced green electricity is indistinguishable from gray electricity so, segregation, testing and re-qualification is meaningless. So green raw materials used in plastics are chemically and physically indistinguishable from conventional materials and therefore also don't require segregation, testing or re-qualification.

Tim Sykes (03:35):

Okay. Thank you. That's a really useful analogy that makes it really clear how it works in principle. So, let's apply this to packaging, our area of interest. And can you give us a reason why the packaging value chain should consider embracing the mass balance approach?

Luc Bosiers (03:55):

Yeah, certainly. The packaging value chain should embrace mass balance as it is the least expensive and fastest way to accomplish a significant shift away from fossil derived raw materials to more sustainable and circular products. And this will help to achieve the globally agreed to CO2 reduction commitments mentioned in the Paris agreement. These commitments are being translated into national regulations, including rules on bio and recycled content in packaging items and other consumer goods. In an ideal world, bio derived or recycled materials would be available in unlimited quantities and would be segregated from fossil derived materials. However, today it's not possible to segregate them because the quantities aren't there yet to justify the investments and building new dedicated plants, storage facilities, et cetera, they cost a lot of money and it also takes a lot of time.

Luc Bosiers (04:52):

So right now, it makes most sense to use existing infrastructure to produce and bring to market sustainable alternatives using the mass balance methodology. It will require commitment by all the players in the value chain to make it happen. The global CO2 reduction goals are ambitious, and it is important that all the players in the value chain and especially the brand owners accept, apply and promote the concept of mass balance to help achieve those goals.

Tim Sykes (05:26):

Thank you. So we've established in general terms the purpose of mass balance and the relevance in the packaging context. And I'm interested now in finding out a bit more about how this applies to the specific context of Trinseo, where you work. First of all, how does mass balance certification relate to Trinseo's own sustainability strategies and objectives?

Luc Bosiers (05:53):

Well, Trinseo is a material solution provider and our goal is to develop materials with sustainable content to help our customers meet their sustainability objectives. So we have key customers in many markets, including automotive, building and construction, consumer electronics, packaging, and so on. And mass balance enables us to give them an exact accounting -- evidence if you will --of the amount of sustainable content in a final product. Our customers can then use the material confidently in their applications, knowing that they are supporting their own corporate sustainability goals and promote it as such to the consumer. Overall, Trinseo has a goal that 40% of our products will be produced with recycled or sustainably advantaged content by 2030, and 50% will support the United Nations sustainable development goals by 2030. Mass balance gives us an exact measurement tool for our progress towards this goal.

Tim Sykes (05:57):

Thank you, Luc. So, that's really interesting to hear, and it's clear that the mass balance certification is a way of demonstrating and giving that transparency of the progress that you're making towards those sustainability objectives, which I guess, the end users in the brand part of the value chain will require to obviously meet and demonstrate their own objectives. I'm really interested in understanding a little bit more how this works in concrete terms. How is mass balance integrated in Trinseo products and certified throughout that polystyrene value chain.’

Luc Bosiers (07:42):

Let's take a yogurt cup as an example. So yogurt cups, as you know, are typically made of blends of high-impact and general purpose polystyrene. And polystyrene can be completely recycled. This is what's so interesting about this polymer. It's unique, simple chemistry allows it to be infinitely recycled using a chemical process called depolymerization. Depolymerization results in a material, post-consumer waste to be reduced back to styrene monomer, which is the essential building block of polystyrene. And this material is identical to virgin styrene, and therefore can be mixed, it doesn't need to be segregated. So the first step is the depolymerization and the styrene monomer production. Post-consumer polystyrene waste is depolymerized yielding a styrene containing oil. This styrene containing oil is added to an existing styrene monomer production unit and gets mixed with virgin raw materials, other raw materials and it gets purified through distillation.

Luc Bosiers (08:50):

The styrene producer now has X tons of recycled styrene available and certified through mass balance methodology and he can sell that quantity to a polystyrene producer with a mass balance certificate. So again, note, there is no segregation of recycled styrene monomer, it's co-mingled with conventional styrene monomer. This brings us to step two. The polystyrene plant receives this quantity of recycled styrene along with the mass balance certificate. Again, there is no segregation. The recycled styrene monomer gets mixed with conventional virgin styrene. In the reactor, we make mass balance certified recycled polystyrene. Again, production losses aren't taken into account and again, there is no segregation. It's only upon bagging or upon bulk loading that we will relabel the product and the percentage of recycled content is allocated using the mass balance rules.

Luc Bosiers (09:59):

Step three, the polystyrene is sold and delivered to a converter, say a polystyrene sheet producer, an FFS sheet producer, with a matching mass balance certificate indicating the amount of recycled content. Again, no segregation needs to be applied and the polystyrene can be stored and mixed with virgin materials. Step four, the converter produces polystyrene sheet, the so-called form fill seal sheet. And he sells a certain quantity of it with a claim that it contains X percent of recycled contents. He sells this volume with a matching mass balance certificate. And then step five, the dairy brand owner. He receives the reels of this polystyrene sheet and the matching accompanying mass balance certificates. And he converts the sheet into dairy cups. He can then attribute the mass balance credits to specific dairy cups, which he markets with the claim, containing X percent of recycled content.

Luc Bosiers (11:01):

In summary, the entire mass balance process through the value chain hinges on four cornerstones. Complete identicality of raw materials. Styrene monomer derived from post-consumer recycled polystyrene sources is chemically and physically identical to that made of fossil sources. Two, segregation of raw materials, semi-finished goods and final products is not needed. ISCC certification by all players is mandatory and mass balance certification accounting throughout the entire value chain is done. A bit similar to blockchain technology.

Tim Sykes (11:40):

Thank you. It's really interesting to see that and I can see how that would be a powerful tool in demonstrating that and giving that visibility throughout the value chain. I'm also interested in just understanding the scale of how far you've come on this journey as an organization at the moment. Are you able to say how many of Trinseo's plants are certified and how did you achieve that designation? What does that involve and what does it mean to you as a manufacturer of resin?

Luc Bosiers (12:15):

Okay. We are implementing the mass balance technology concept in our entire portfolio. We are implementing it in the styrene monomer. We're implementing it in our styrenic polymers, in polycarbonate, rubber and latex. And already certified today are our polystyrene plant in Tessenderlo (Belgium),our polycarbonate plant in Stade, Germany, our synthetic rubber plant in Schkopau, Germany and our styrene monomer facility in Terneuzen, in The Netherlands. In July, we added our latex factory in Rheinmunster, Germany to that list and later this year in September, we will also add ABS and SAN, in Terneuzen, in The Netherlands, as well as latex in Terneuzen, in the Netherlands to this list. So, that encompasses our complete product mix. And in preparing for the certification, we work closely with the certification body ISCC. They are the global leader in this field and their experts provided good help in preparing the official audit.

Tim Sykes (13:26):

Finally, I'd like to ask you how you see things developing beyond the current situation. How do you assess the future of mass balance?

Luc Bosiers (13:35):

Well, I'm convinced that mass balance is here to stay. I mean, the mass balance concept is already broadly accepted by the chemical industry and by the many markets we serve. Leading brand owners across the world, participating in hugely different markets, understand the benefits of mass balance in the sense that it's the best, fastest, and economically most sensible way to meet the ambitious goals of the Paris agreements in massive reduction of CO2 footprint in everything we do, make and buy. The emphasis on sustainability is accelerating, so while the volumes of sustainable materials today are limited, we are going to see significant growth. And polystyrene recycling is one area that Trinseo is heavily involved in. For example, the recently announced investments by Trinseo and by others will lead to very significant volumes of recycled polystyrene in Europe as of 2023. Over 80,000 metric tons per year of polystyrene containing 50% bio derived styrene, or containing 50% recycled content will be available as of then, with significant further growth expected in the years to follow. So, you're going to see this in every product category.

Tim Sykes (14:56):

Thank you very much, Luc. So, that's all we have time for today. If you're interested in this topic, you can hear from and engage with sustainability pioneers and thought leaders from different points in the value chain via our year-round series of virtual sustainable packaging summit panels, workshops, videos, and podcasts. And I think we will be touching on the topic of mass balance later in the year in our live content. And you can reach all of that via the event platform, packagingsummit.earth/join or through the packaging Europe website. For now, thanks for watching and special thanks, Luc Bosiers for joining me today.

Luc Bosiers (15:37):

Thanks for having me, Tim.

Tim Sykes (15:39):

Goodbye.



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