Green Economy Journal Issue 63

CIRCULARITY
CIRCULARITY
(think water and biomass) but are less prevalent in man-made
systems. Converting fossil fuels and minerals into energy and
materials is a prime example of man-made open-loop processes in
which finished products are discarded or accumulate in unwanted
forms, such as CO 2 emissions.
Exceptions do exist. Notably, 50% to 90% of aluminium is recycled
(depending on the application), and other metals such as steel, copper
and zinc also have recycling rates above 50%. 2 Nevertheless, only 9%
of all human-produced end-of-life materials and energy are recycled.
For plastics, that rate is 20%, with polyethylene terephthalate (PET)
being among the highest at 29% to 58% across the US and Europe,
leaving a significant opportunity on the table for recycling. 3
What is special about plastics, and what are its circular scenarios?
Chemical products, including plastics, have improved the quality
of life for people across the globe over the past century. Useful
properties and versatility combined with low cost have allowed
these products to proliferate and deliver significant benefits
to consumer convenience, industrial processes, logistics and
public health. Unfortunately, these benefits have come with
an environmental cost. Packaging, for example, accounts for at
least a third of plastics usage and presents one of the most acute
challenges for closing the loop.
To understand the potential path to creating a circular value
chain for plastics, it’s helpful to look at other materials that have
similar usage patterns. For example, the aluminium value chain
highlights some of the potential success factors while also revealing
the unique factors that must be addressed for plastics. Historically,
aluminium was mostly used for durable products in construction,
transportation and other heavy industries. Although aluminium
packaging had existed before, it accelerated in the 1960s with the
explosive growth of beverage cans. As aluminium entered the public
consciousness, with it came a call for recycling. The aluminium
recycling process begins with collecting scrap at the point of use
followed by aggregation, melting, purification and remixing with
virgin feedstock (Figure 1).
The main lessons from this closed-loop process include valuation
of the scrap material to incentivise its capture, a mixed mechanical
and chemical recycling value chain, purification technology and
favourable economics that create a cost advantage for using recycled
material rather than virgin feedstock.
Recycling value chains for plastics are less well-established than
those for metals. Single-material circular value chains, which we refer
to as small-loop scenarios, are presently the most common, such
as polyester material in PET bottles. The path forward for greater
circular flows of plastic will involve a combination of plastics-specific
small-loop scenarios and multiple-plastic, large-loop scenarios
(Figure 2).
Closed-loop value chain for aluminium
CLOSING THE LOOP
Man-made open-loop systems are centuries old – converting natural resources into energy
and materials in a linear process of make, use and dispose. These systems fuelled the Industrial
Revolution, which elevated the quality of life and economic condition of people globally. Yet,
these processes generate huge amounts of waste and are now considered unsustainable.
Figure 1. The metals industry has a well-established recycling process.
Potential closed-loop value chains for plastics
BY KEARNEY CONSULTING
Plastics, along with energy, are central to this issue given the
waste and emissions created in the linear systems used for
their production. Images of plastic waste in beautiful natural
ecosystems such as beaches and oceans along with information
about the potential environmental impact have prompted a
growing and emotional public call for action.
Despite the many applications and benefits, including being
versatile, lightweight, cost-effective, safe and clean; plastic materials
– more than $500-billion of global product value – are now more
vulnerable than ever to public and government scrutiny. 1 To
respond, plastics producers and consumer companies are taking
a range of actions, from redesigning their products to reduce how
much plastic they use and opting for renewable sources instead
of fossil-based feedstock to reusing and recycling.
Recycling through viable circular chains has the power to stem
the negative tide and secure the use of plastics. For chemical and
consumer companies on the journey to address the opportunities
and challenges of the circular economy, success will depend on
recognising the unique characteristics of the plastics value chain,
understanding the forces that will drive future models and planning
an appropriate course of action.
What is a circular value chain?
In its simplest form, a circular system has inputs that remain in
the system and are reused rather than expelled as waste. In a
circular economy, the value of products, materials and resources
is maintained in the system for as long as possible, and waste is
minimised. These closed-loop systems are easily found in nature
Figure 2. A circular system for plastics is likely to involve two closed-loop models.
50% to 90% of
aluminium is recycled.
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