Advancing Sustainability (part 1 of 2)

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2020/04/10 Advancing Sustainability (part 1 of 2)

Advancing Sustainability
Head of Sustainable Packaging Coalition discusses the prospects for packaging’s role in improving the environment.

Source from: https://www.flexpackmag.com/articles/90389-advancing-sustainability

Sustainability has become the mantra of the packaging world. No matter which way you look, companies are developing new products and processes that will reduce packaging’s impact on the environment.

Nowhere is this movement more critical than in the flexible packaging space. Currently, flexible packaging is the fast-growing segment of the industry. The main factor limiting its growth is recyclability, since many pouches and bags use laminated structures of different materials that are difficult to recycle. And plastics, the primary material, can take centuries to break down in the environment.

If anyone has an awareness of how the industry is progressing, that person would be Nina Goodrich, director of the Sustainable Packaging Coalition. Flexible Packaging recently met with her to discuss advances in packaging sustainability. Goodrich has held leadership positions in sustainability and R&D with Alcan Packaging, Amcor, Guelph Food Technology Center and Magic Pantry Foods. She also has done graduate work in technology management and holds a BA in molecular biology from Wellesley College.

Benefits of Flexible Packaging
Goodrich says flexible packaging is a very valuable form of packaging because it has a low carbon footprint and it offers a high level of product protection. Many people lose sight of the fact that if a product spoils or gets damaged, that is not very sustainable because the footprint of the product is often greater than that of the package. Where flexible packaging often falls down is on recyclability.

“The focus has been on plastics in the last year, but I think the focus needs to be on all materials,” Goodrich says. “We need to create an infrastructure that allows all materials to be collected, sorted and reprocessed to become feedstock for other processes.” She adds that that a circular economy is absolutely critical, and it is bigger and more important than just recycling.” We can’t have status quo answers to these big problems.”

Many companies are making tradeoffs with unintended consequences. “All materials have tradeoffs. It depends on what you think is more important. If you think climate change is important, it doesn’t make sense to move to materials with a higher carbon footprint and less performance capability,” Goodrich says. “Everybody making these decisions really needs to think about it. I think the answer is infrastructure for all materials, and we haven’t really been good for any of them.”

Many brand owners and consumers think that recycling is the best way to make packaging more sustainable. Today, mechanical recycling is the main method used to recover and reuse materials used in packaging.

Mechanical recycling refers to operations that aim to recover plastics waste via mechanical processes, such as grinding, washing, separating, drying, re-granulating and compounding. Mechanical recycling can only be done a few times before the polymers break down and the quality of the plastic degrades.
However, this is not easily accomplished with flexible packaging because it often combines multiple materials that cannot be separated and which may contaminate the recycling process. Consequently, many recycling facilities will not accept flexible packaging. This reduces its value in the recycling marketplace.
Goodrich says the industry really needs a way to collect film that is not dependent on being sorted in material recycling facilities (MRF). Today, it costs $80 a ton to sort the current mix of materials in an MRF, while the combined sale value is somewhere between $30 and $40 — and that’s for rigid materials and paper, not flexibles.

Recycling Flexibles Is Expensive
“The last thing we want to do is send flexibles through that system to incur the burden of that cost,” she says. “We need a new way of collecting recyclables. My belief is that some version of the current Energy Bag solution where films and hard-to-recycle materials could be placed in a bag and then picked up in curbside collections. It would then go in a different direction.”

She also points out that the market is seeing a surge of companies wanting to move out of multilayer flexible packaging and into single-layer polyethylene because that can be recycled at store drop-offs.

“Companies should not be making large investment decisions based on the ability to recycle packaging through store drop-offs,” Goodrich says. “We need a better solution than that. That’s a temporary solution — something that we can do today.”

The one thing that Goodrich says excites her about flexible packaging today is the work that is going on to increase the performance of monomaterial resins. Companies are figuring out ways to engineer plastics with improved performance properties. Some additives that can enhance film performance the second or third time around are critical to keeping materials in play.
Chemical recycling is another set of emerging technologies that might offer an alternative to material mechanical recycling. Chemical recycling can help reduce the amount of plastic waste that ends up in landfills or incineration. Pyrolysis and gasification are forms of chemical recycling that are used to turn plastic polymers back into building blocks individual monomers, which allows materials to be reused in a variety of ways.

Safe Processing of Mixed Materials
Goodrich likes the idea of chemical recycling because it would allow the safe processing of mixed materials into reusable materials. Most resins used for flexible packaging are polyolefins, most commonly polyethylene and polypropylene.

Polyethylene and polypropylene are addition polymers, and they’re the very best they can be the day they are born. They are made of very long carbon chains. Every time they are recycled the molecules get shorter, so you need to add more material — similar to paper where fibers get shorter each time they are recycled until they wash out.

When you chemically recycle polyolefins, the super-long carbon chain is going to break into different pieces to produce gases like methane, some liquids like diesel fuel and some solids like waxes. The process can be manipulated to some degree depending on what you want.

Some of the fuel-type materials could potentially be turned into precursors for polypropylene or polyethylene, she says. That’s an expensive proposition and requires extra steps. Some the other industrial materials like the waxes can be sold and used directly for use in products like roofing tiles.

Goodrich explains that the industry still has much to learn about mechanical recycling. There are performance limitations on being able to incorporate the recycled materials back into packaging. There are differences between the type of food contact qualifications they can receive. Some have letters of non-objection for food contact. Others have qualified letters for food contact, such as recycled polypropylene cups where the drink is only in the cup for a short time as opposed to a product that is actually going to be stored in the material.

Recycling into Packaging Not Always Feasible
She cautions that it seems crazy to try to mechanically recycle the flexible post-consumer material back into high-performance packaging. Applications for films with film PCR will be limited to products like trash bags.

There is an enormous amount of film material available. Post-consumer mechanical recycling may not make the most sense when there are large amounts of post-commercial material, such as stretch wrap, that is much cleaner. In 2021 there may be even more material available when the Basel convention comes into effect and may prohibit the export of plastic materials that are not high quality,

Post-consumer films are really well-suited for chemical recycling. Regional pyrolysis facilities that could create precursor materials would allow shipping of materials as liquids, which are much denser than flexible packaging. These could then feed into the larger supply chain.

“If you look at the flexible packages that have post-consumer content in them, that content is usually coming from milk jugs,” she says. Rigid PE milk jug containers (natural not colored) have the highest value compared to other plastic materials. This material is preferred for almost every type of post-consumer food application and there is not enough of it available. She pointed to a recent CEFLEX trial in Europe, which found that only a small percentage (20 percent of post consumer collected films were suitable to be used for recycle content applications.)

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