Plastic recycling

Plastic recycling
Clockwise from top left:
  • Sorting plastic waste at a single-stream recycling centre
  • Baled colour-sorted used bottles
  • Recovered HDPE ready for recycling
  • A watering can made from recycled bottles

Plastic recycling is the processing of plastic waste into other products.[1][2][3] Recycling can reduce dependence on landfill, conserve resources and protect the environment from plastic pollution and greenhouse gas emissions.[4][5] Recycling rates lag those of other recoverable materials, such as aluminium, glass and paper. From the start of production through to 2015, the world produced some 6.3 billion tonnes of plastic waste, only 9% of which has been recycled, and only ~1% has been recycled more than once.[6] Of the remaining waste, 12% was incinerated and 79% either sent to landfill or lost into the environment as pollution.[6]

Almost all plastic is non-biodegradable and without recycling, spreads across the environment[7][8] where it can cause harm. For example, as of 2015 approximately 8 million tons of waste plastic enter the oceans annually, damaging the ecosystem and forming ocean garbage patches.[9] Even the highest quality recycling processes lead to substantial plastic waste during the sorting and cleaning process, releasing large amounts of microplastics in waste water, and dust from the process.[10][11]

Almost all recycling is mechanical: melting and reforming plastic into other items. This can cause polymer degradation at a molecular level, and requires that waste be sorted by colour and polymer type before processing, which is complicated and expensive. Errors can lead to material with inconsistent properties, rendering it unappealing to industry.[12] In feedstock recycling, waste plastic is converted into its starting chemicals, which can then become fresh plastic. This involves higher energy and capital costs. Alternatively, plastic can be burned in place of fossil fuels, in energy recovery facilities or biochemically converted into other useful chemicals for industry. In some countries, burning is the dominant form of plastic waste disposal, particularly where landfill diversion policies are in place.

Plastic recycling is low in the waste hierarchy. It has been advocated since the early 1970s,[13] but due to economic and technical challenges, did not impact plastic waste to any significant extent until the late 1980s. The plastics industry has been criticised for lobbying for expansion of recycling programs, even while research showed that most plastic could not be economically recycled.[14][15][16]

  1. ^ Al-Salem, S.M.; Lettieri, P.; Baeyens, J. (October 2009). "Recycling and recovery routes of plastic solid waste (PSW): A review". Waste Management. 29 (10): 2625–2643. Bibcode:2009WaMan..29.2625A. doi:10.1016/j.wasman.2009.06.004. PMID 19577459.
  2. ^ Ignatyev, I.A.; Thielemans, W.; Beke, B. Vander (2014). "Recycling of Polymers: A Review". ChemSusChem. 7 (6): 1579–1593. Bibcode:2014ChSCh...7.1579I. doi:10.1002/cssc.201300898. PMID 24811748.
  3. ^ Cite error: The named reference cycles was invoked but never defined (see the help page).
  4. ^ Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward (27 July 2009). "Plastics recycling: challenges and opportunities". Philosophical Transactions of the Royal Society B: Biological Sciences. 364 (1526): 2115–2126. doi:10.1098/rstb.2008.0311. PMC 2873020. PMID 19528059.
  5. ^ Lange, Jean-Paul (12 November 2021). "Managing Plastic Waste─Sorting, Recycling, Disposal, and Product Redesign". ACS Sustainable Chemistry & Engineering. 9 (47): 15722–15738. doi:10.1021/acssuschemeng.1c05013.
  6. ^ a b Cite error: The named reference Geyer2017 was invoked but never defined (see the help page).
  7. ^ Andrady, Anthony L. (February 1994). "Assessment of Environmental Biodegradation of Synthetic Polymers". Journal of Macromolecular Science, Part C: Polymer Reviews. 34 (1): 25–76. doi:10.1080/15321799408009632.
  8. ^ Ahmed, Temoor; Shahid, Muhammad; Azeem, Farrukh; Rasul, Ijaz; Shah, Asad Ali; Noman, Muhammad; Hameed, Amir; Manzoor, Natasha; Manzoor, Irfan; Muhammad, Sher (March 2018). "Biodegradation of plastics: current scenario and future prospects for environmental safety". Environmental Science and Pollution Research. 25 (8): 7287–7298. Bibcode:2018ESPR...25.7287A. doi:10.1007/s11356-018-1234-9. PMID 29332271. S2CID 3962436.
  9. ^ Jambeck, Jenna, Science 13 February 2015: Vol. 347 no. 6223; et al. (2015). "Plastic waste inputs from land into the ocean". Science. 347 (6223): 768–771. Bibcode:2015Sci...347..768J. doi:10.1126/science.1260352. PMID 25678662. S2CID 206562155.{{cite journal}}: CS1 maint: numeric names: authors list (link)
  10. ^ Paul, Andrew (8 May 2023). "Recycling plants spew a staggering amount of microplastics". Popular Science. Retrieved 8 May 2023.
  11. ^ Brown, Erina; MacDonald, Anna; Allen, Steve; Allen, Deonie (1 May 2023). "The potential for a plastic recycling facility to release microplastic pollution and possible filtration remediation effectiveness". Journal of Hazardous Materials Advances. 10: 100309. doi:10.1016/j.hazadv.2023.100309. ISSN 2772-4166. S2CID 258457895.
  12. ^ Cite error: The named reference EU-demand was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference The Plastics Issue was invoked but never defined (see the help page).
  14. ^ National Public Radio, 12 September 2020 "How Big Oil Misled The Public Into Believing Plastic Would Be Recycled"
  15. ^ PBS, Frontline, 31 March 2020, "Plastics Industry Insiders Reveal the Truth About Recycling"
  16. ^ Dharna Noor (15 February 2024). "'They lied': plastics producers deceived public about recycling, report reveals". theguardian.com. Retrieved 16 February 2024.