Achieving Circularity Through Composting and Biopolymers
The Need for Proper Handling of Compostable Alternatives in the RRC Triad
In my previous post, “Why Achieving Reusable, Recyclable, or Compostable (RRC) Targets Are Being Missed”, I emphasized, as reported by the Ellen McArthur Global Commitment 2022 Progress Report that “Compostable” in the RRC triad (Recyclable, Reusable, Compostable), has been for the most part ignored by major brands (0% out of 65% compliance progress). It’s obviously clear that it is easier for brands to report on the recyclability of its packaging, even though they do not bear any responsibility for their “recyclable” packaging to be actually recycled. Producing recyclable products is just the first step in achieving circularity, but much more needs to be done for the recyclable product to be recycled and then to return that recycled material into productive use. If the subsequent steps are not achieved, any benefit of recyclable products will never be realized. More than that, such recyclable material will become a major pollutant. That is where we are today.
However, not all is lost. Composting, the “C” in RRC, represents a fundamentally different paradigm, with Bio-Polymers presenting a completely different alternative.
Circularity of both conventional polymers and biopolymers can be achieved, if handled properly through the collection and processing infrastructure and appropriate recycling technologies. Of these, biopolymers represent less risk of plastic contamination and pollution, especially with respect to product “leakage” into the environment.
It should be noted however, that not all biopolymers are created equally, and their potential impact on the environment strongly depends on their ability to degrade, and the conditions necessary to achieve a complete or near-complete degradation, along with the residual impact on the environment. There is also an important consideration related to the recyclability of products made from biopolymers. Not all such bio-based polymers can be effectively recycled.
Existing classification of biopolymers traditionally distinguishes between bio-based polymers (those derived from bio-based sources) and bio-degradable (those that can be composted under various conditions). Bio-based polymers that are not compostable/degradable are equally as harmful as conventional plastics when spilled into the environment. A well known example of a product made from bio-based polymers is the “plant bottle”. Even though the PET used in the production of these bottles was bio-based, in the end, these bottles were no different from PET bottles produced from hydrocarbons, and they pollute the environment in exactly the same way, if not recycled properly. They also result in the same amount of microplastics discharged into the environment as any traditionally produced plastic bottle.
Biopolymers: A Promising Alternative for Achieving Circularity in Plastic Packaging
Understanding the Role of Composting and Bio-Based, Compostable Polymers in Sustainable Packaging
At present, there are several groups of bio-based, bio-degradable materials that satisfy the conditions of “Compostable” in RRC that provide the biggest positive impact in meeting the sustainability goals of major brands. Polyhydroxyalkaonates (PHAs) is a group of bio-based materials that emerge as the most promising, with a wide variety of physical and mechanical properties that can replace conventional plastics in several applications where non-recyclable plastics currently dominate. We believe that PHAs are closer than any other compostable alternative to meeting three key elements of viability, described in the previous post: (1) availability of functional solutions, (2) economics and scalability of these solutions, and (3) availability of infrastructure and regulatory support. Currently, there are only a few PHA-based products offered in the marketplace. There is much more that needs to be done to create a meaningful presence of compostable packaging on the shelves of our stores.
It should be emphasized that PHA-based products, or other products made from bio-based, compostable polymers are NOT supposed to fully replace conventionally produced and properly recycled plastics. For example, beverage containers made from recycled PET are the most efficient way to achieve circularity in that segment of packaging. PET containers are easily recycled and the respective infrastructure exists and continues to grow. Effective technologies exist to convert post-consumer PET into material perfectly suitable for the majority of regular applications. At the same time, many other polymers are NOT recycled and that contributes to the overall negative view of plastics as a major pollutant (actual recycling rate of 9% for all polymers does not help). While it is highly unlikely that PHA can replace all non-compostable polymers, it is definitely a great first step in achieving circularity in a sizeable segment of plastic packaging products that are currently NOT recycled and end up in landfills and waterways, while shedding substantial amount of microplastics in the process.
Our next post will be devoted to describing specific products that we believe can be economically produced from PHA, and our recommendations for the most efficient path forward to that objective.