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Abstract
This study addresses two key questions: (a) should we recycle plastics? and (b) what are the carbon footprints of virgin and recycled PET, vPET and rPET? (PET is the common abbreviation for polyethylene terephthalate.)
It does so by calculating the carbon footprint for PET bottles used to package drinks. The footprint is "cradle to grave," i.e., extending from production of raw materials (primarily oil and gas) through to disposal of all wastes. The study considers a base case—bottles are used by consumers in northwest Europe, collected in a curbside system and sent on for sorting and recycling—and variations on that, including PET-only take-back (as currently practiced in Switzerland) as well as no recycling (with scenarios of "all landfill" and "all incineration"). Sensitivities of all major variables are assessed.
The study concludes that the curbside take-back systems are no better than landfill. From a carbon-emissions standpoint, it would be just as well to bury used bottles as to recycle them, and either would be a better option than burning them. This has several important implications: (a) for regions that already have a recycling infrastructure, the aim should be to maximize rPET displacement of vPET, even if this involves long-distance transport to recycling plants (say, in China). The key here is not in raising collection rates, which already hover near their practical maxima, but in improving yields, especially in sorting and to a lesser extent in reprocessing. For countries without a recycling infrastructure, the best choice may well be to landfill bottles. Call it "carbon capture and storage" if you will, on an economy budget.
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