Environment & Energy

NNadir

(36,937 posts) Tue Nov 4, 2025, 09:46 PM Nov 4

Inequities from the Embedded Plastic Flow and Carbon Footprint Transfers in International Trade

There's a nice illustrative graphic on the flow of plastics in the paper to which I will briefly refer in this post, this one: Inequities from the Embedded Plastic Flow and Carbon Footprint Transfers in International Trade Shang Zhang, Jinhui Li, and Quanyin Tan Environmental Science & Technology 2025 59 (42), 22554-22565.

From the paper's introduction:

Plastic is deeply embedded in everyday life and part of industrial production and its consumption has increased exponentially over the last decades worldwide. (1−3) Plastic waste nearly doubled from 2000 to 2019, reaching 353 million tons (Mt) globally. (4) Extremely slow degradation, coupled with spreading via rivers and oceans, causes increased pollution, impairs ecosystems, (5−7) and is a threat to human health. (8) Furthermore, plastic production is projected to double by 2050 and triple by 2100, exacerbating plastic pollution. It has also been predicted that by 2050, greenhouse gas (GHG) emissions from the plastic system will increase by 37%, reaching 3.35 billion tons of CO2 equivalent. (9) To combat this situation, an increased number of multilateral initiatives have recently commenced addressing plastic pollution. In 2024, the fifth session of the Intergovernmental Negotiating Committee (INC-5) for the development of an international, legally binding instrument on plastic pollution took place. However, consensus on a global plastic treaty was not reached, and the international community resumed the INC meeting in 2025. The resumed fifth session (INC-5.2), held in the first half of August 2025, concluded without agreement after negotiations extended beyond the planned schedule. (10) This outcome further underscored the significance of resource efficiency and the role of international trade in plastics and plastic products, while reaffirming the continued importance of addressing global plastic consumption and strengthening transparency across supply chains in the ongoing negotiations. (11)

The international community is calling for research on elucidating material flow and future trends in plastic to facilitate concerted worldwide action. Previous studies concentrated on future trends in plastic production and associated material flows at the global, (12−15) regional, (16−19) and national levels, (20,21) with a focus on China (22−25) (Table S1)...

The graphic of interest:

The caption:

Figure 1. Global value-chain of embedded plastic exported from China in 2022.

"RoW" in this graphic is the abbreviation of "Rest of the World."

A graphic on carbon impact:

The caption:

Figure 4. Carbon footprint linked to embedded plastic exported from China in 2022. (a) Global value-chain of carbon footprint (GHG emissions). (b–g) Top 6 countries and regions with the highest carbon footprint. The inner ring represents the sectoral proportion of direct consumption, while the outer ring represents the sectoral proportion of indirect consumption.

I am somewhat ambivalent about plastics. I try to avoid, as much as possible - although to be honest with myself, I often fail - using single use plastics. In modern times this is nearly impossible, but I do what insignificant bit I can.

In theory, the word "theory" being the most important operative word, plastics made from CO₂ via the hydrogenation to methanol followed by the MTO "methanol to olefins" process would sequester carbon if obtained from the atmosphere, possibly via seawater. This would amount to sequestering carbon by use, that is make plastics carbon negative.

The energy demands of such a process would be formidable, even allowing for the wise use of process intensification by increasing the exergy recovery from heat. Reducing carbon dioxide to carbon or carbon based polymers requires the investment of all the energy that created it (overwhelmingly from the combustion of fossil fuels) as well as additional energy to overcome the entropy of mixing. This cannot be done, no matter how strong the fantasy flies in the face of reality, with so called "renewable energy." To avoid a perpetual motion machine, the only possible pathway is, as in my oft stated view, nuclear energy. There is, regrettably, little or no time left for nuclear energy to do what it might have done however. The delays caused by irrational antinukism has left us in a hard place.

Have a nice day tomorrow.