Imogen Aley
All over the world, millions of tons of plastic are being disposed of daily, though less than 6% of plastics are recycled. Much of this plastic ends up in landfills, our oceans, our waterways, leaching toxins into soils and producing microplastics that destroy ecosystems and damage human health. There have been many attempts at dealing with this problem, one of which is the chemical recycling of plastics, also known as plastic pyrolysis.
Plastics are created using petroleum and other hydrocarbons which include additives that prevent biodegradation and create problems for recycling. Plastic pyrolysis allows non-recyclable plastics to be recycled back into their building blocks; specifically oil and natural gas. To achieve these raw materials, plastic is processed in the absence of oxygen and in the midst of extremely high temperatures that rise up to 1500 degrees Fahrenheit. The resulting oil and natural gas are then used to create new plastics or to be burned as fuel.
The idea of chemical recycling may seem to be an environmentally conscious alternative to both plastic disposal and the mining of fossil fuels, however, it is debated by environmentalists whether it really is beneficial. One of the main issues with plastic pyrolysis is the sheer amount of heat it requires to break down the plastic, which is acquired by burning natural gas. The toxins and harmful greenhouse gasses released as byproducts of burning natural gas have the potential to outweigh the benefits of disposing of plastic. Furthermore, the idea of creating new fossil fuels to use perpetuates the need for fossil fuels and increases reliance on them as energy sources. Although plastic pyrolysis recycles plastic, the creation of new fossil fuels to be burned will release more carbon dioxide into the atmosphere. Thus, putting the label of ‘recycling’ onto plastic pyrolysis may make the idea seem sustainable when actually it damages the environment.
Despite its controversy, plastic pyrolysis and chemical recycling in general provides valuable insight into how non-recyclable materials should be dealt with. Though the process is more lengthy and elaborate, chemical recycling of plastics allows even those plastics that are contaminated with other chemicals to be recycled, instead of taking up space in landfills and further damaging our waterways. Furthermore, although renewable energy resources are on the rise, so much of the world still relies on the use of fossil fuels. As such, chemical recycling provides a form of energy recovery from materials that are made from energy sources. Also, as chemical recycling is a relatively new industry, there is opportunity for a number of jobs to be provided both on the industry side and the research side.
Citations
Rashid Miandad et al, “Catalytic Pyrolysis of Plastic Waste: Moving Toward Pyrolysis based Biorefineries” frontiers 03/19/2019 https://www.frontiersin.org/articles/10.3389/fenrg.2019.00027/full
James Bruggers, “A New Plant in Indiana Uses a Process Called ‘Pyrolysis’ to Recycle Plastic Waste. Critics Say It’s Really Just Incineration” Inside Climate News 11/11/2022 https://insideclimatenews.org/news/11092022/indiana-plant-pyrolysis-plastic-recycling/
Ana Baranski, “Plastic Pyrolysis Pros and Cons: Converting Plastics Into Energy” Profolus 05/25/2021 https://www.profolus.com/topics/plastic-pyrolysis-pros-and-cons-converting-plastics-into-energy/
“Plastic Recycling News | Pyrolysis, a new future for plastics?” Plastic Expert https://www.plasticexpert.co.uk/plastic-recycling-pyrolysis/
Tom Fisk, “People Working on a Dump Site at Sunset” Pexels, 10/26/2020 https://www.pexels.com/photo/people-working-on-a-dump-site-at-sunset-5412975/
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