In the following article, The Earth & I covers Professor Michael Shaver's presentation given at the 28th International Conference on the Unity of the Sciences (ICUS) entitled, “Sustainability, Plastics, Systems—One Bin to Rule Them All.” Prof. Shaver is the Director of Sustainable Futures at The University of Manchester, UK. An official, edited version of Prof. Shaver’s presentation will be published in the ICUS XXVIII Proceedings in the future.
Plastics can be seen as the bane of any environmentalist’s existence due to their reputation as the primary source of single-use waste, such as from plastic bottles, cups, and straws. However, plastics (or polymers) are an indispensable part of modern society. They are the building blocks found in appliances, clothing, and electronics, as well as being prevalent in applications such as packaging and sanitation. It may be counterintuitive, but alternatives to plastics often end up producing more waste and carbon dioxide.
An example is the use of Styrofoam cups versus ceramic cups. Single-use plastics (including Styrofoam) are notorious for their contribution to waste and water pollution in particular.
However, from a resource consumption perspective, over 500 Styrofoam cups could be made, transported, and used before they reach the energy costs of one ceramic cup. In addition, in general, it is estimated that using plastics over alternatives saves 582.6 million gigajoules (GJ) of energy per year, corresponding to 100 million barrels of oil.
However, given how long it takes Styrofoam and other plastics to break down once in the environment, their environmental impact could be lowered by them being properly recycled and reused instead.
“So, the consequences for a plastics-free world are really significant. And so the argument is that we have to have a waste management system that recovers value from all plastics. Which means we’re not seeking something like a sustainable plastic. We’re seeking a sustainable system in which that plastic exists,” Professor Michael Shaver told the Twenty-Eighth International Conference on the Unity of the Sciences (ICUS XXVIII).
One Bin to Rule Them All
Prof. Shaver is a lead researcher of a project at The University of Manchester (UK) called “One bin to rule them all.”
The project started in November 2020 and is scheduled to end in October 2023. It is organized by a consortium led by The University of Manchester with cooperation from seventeen companies and UK authorities.
The purpose of the project is to “improve compliance with recycling [in the UK] by developing ‘One bin’ to hold all plastic-like items and improving recycling infrastructure to create more usable recycled plastics that can be fed back into a circular economy.” As the project name suggests, consumers would discard all their unwanted plastics into a single bin. Recyclers would sort the plastics later. The automatic sorting process would happen more swiftly if all plastics were created with hidden barcodes, marker molecules, embossed codes or flexible semiconductors that sorting machines could easily identify.
This would require cooperation from everyone in the plastic supply chain, including manufacturers, brand owners, and local waste management, in an integrated business model to ensure that plastics are reused, recycled, and disposed of properly in a circular economy.
It also requires shared industry standards for tagging plastics. As Prof. Shaver explained: “[A]ll that we’re doing is really identifying decisions that can be made and recognizing the increase in both material value and economic value that is enabled through that. … It requires us to have open data standards on waste management across the system. And it requires us to have shared business models instead of isolated business models.
“One Bin” envisions a circular economy in which plastics are reused, recycled, and disposed of properly through cooperation between all relevant stakeholders, including manufacturers, brand owners, and local waste management under a shared business model.
“What’s really important is that this exists across the supply chain,” he added. “So, this is not just isolated into a particular silo, but in fact really integrated across that whole system to ensure it works for all actors and all stakeholders who are involved.”
As part of the ‘One bin to rule them all’ project, Prof. Shaver and his team focused on developing “an agenda for future research” through twenty-five interviews with senior industrial and commercial management leaders and a cross-sector workshop, with the study published as an open access article.
Four Areas of Agreement
By the second stage of the study, twenty interviews were completed, and thirteen partners attended a full-day workshop. The workshop participants were able to formulate open-ended questions regarding an ideal circular plastics economy following discussion around 1) standardization of materials, 2) sorting and technology, 3) value creation, and 4) pilot trials. They reached four broad areas of agreement—on standardization, infrastructure investment, collaborative business models, and value creation—although these will require certain systemic changes to be made.
Standardization refers not only to a universal manufacturing criterion of the plastics themselves (PET, HDPE, PP, and the like), but other elements pertaining to contamination and disposal. These include the use of adhesives, color pigments, labels, lacquers, and laminates used with plastics, as well as descriptors such as “biodegradable” and “compostable.”
Infrastructure investment refers to setting up systems that incentivize recycling and reusing plastics and make them economically feasible. Current deterrents cited in the UK include the lower cost of virgin plastics versus recyclates and increased profitability of Plastic Export Recovery Notes (or exporting plastics for burning) over Plastic Recovery Notes (or plastic recycling after contaminants have been removed).
Collaborative business models would include not only the tagging techniques outlined above, but they would also include reporting the volumes of individual plastic products sorted for recycling. This information will reduce disposal burdens based on current legislation (Extended Producer Responsibility) in the UK.
Value creation refers to improving the desirability of discarded plastic materials through advanced sorting and higher purity recyclates. Producing cleaner recyclates will encourage the creation of a circular economy in addition to increasing recycling and reuse.
Sorting plastic requires numerous factors to be considered, including the following:
Multi-materials versus mono-materials
Food versus non-food
Bottles versus trays
Colored versus natural
Melt flow indices
Mechanical versus chemical recycling
Systemic changes (with cooperation from local governments), including standardization, infrastructure investment, collaborative business models, and value creation, need to be implemented to create a circular economy for plastics.
In his presentation, Prof. Shaver stressed how the development of tagging will encourage recycling activities as well as help persuade governments to get involved.
“What’s important to recognize is that all these tags will enable a decision,” said Prof. Shaver. “[A]s soon as an infrastructure investment is made, you enable another decision. And you can then work with governments to say, ‘Oh, OK, if you invest in this infrastructure, you can now unlock this potential fate,’ because the sorting mechanism is already there.
“That doesn’t mean there aren't any risks associated with it, so if something like switching that final pathway from chemical recycling to biodegradation, there’s a lot of other things you need to think about in that system. But it gives you the potential to potentially work,” he said.
Recycled, Biodegraded, Composted, and Reused
Plastics are an essential part of society, and replacements often require more energy and resources to produce. Instead of focusing on the elimination of plastics as the goal, we can focus on creating a sustainable system in which those plastics exist.
This will require cooperation from supply chain businesses, local governments, and the active participation of consumers to ensure that the plastics are recycled in the first place. The ‘One bin to rule them all’ project is an example of a starting point of bringing relevant stakeholders together to discuss how a sustainable system, or circular economy, for plastics can be implemented.
Once sustainability is coupled with economic growth, this will provide an incentive for decisions toward a sustainable system.
During the session discussion following Prof. Shaver’s presentation, he responded to a question regarding the challenge of plastics in India. “[I]f you show that environmental sustainability is enabled alongside economic growth, because you’re de-risking things, because compliance costs are less, because systems are more efficient—that unlocks change. And tying those two narratives together has been really useful in our work with [the] UK Government, and with some international plastics trade bodies.”
As the general populace becomes more educated, more actions can be taken to enable an economy in which the plastics people use are also regularly recycled, biodegraded, composted, and reused. Just thinking of things as recyclable, biodegradable, compostable, or reusable does not matter. Instead, Prof. Shaver said, “The only thing that matters is that things are recycled, biodegraded, [and] reused. We have to focus on enabling an actual fate—not an imagined fate.”