Évaluation de l’effet de la spatialité sur la performance environnementale du recyclage des bouteilles de PET

Abstract

Recycling is a growing end-of-life management option. It allows the use of secondary raw materials, that came out of a transformation process, instead of the sole use of fossil fuels materials. Nevertheless, recycling requires the involvement of types of transformation processes different from those found in the initial value chain and additional distances to connect them. The recycling efficiency is partly based on those distances, but also on other intrinsic characteristic of the territory, such as the electricity mix. There are, however, few studies linking recycling with spatial parameters and measure the impact of territorial features on the performance of the entire value chain. Each process, whether it transforms or not the matter, is considered and participates in the total greenhouse gases emissions calculation. The main aim of this study is to measure the impact of territorial features on the environmental performance of the PET bottle recycling through the North America scale (Canada and United States). The main indicator used is the amount of equivalent CO2 emitted per bottle (500mL; 26 g of PET) throughout the entire value chain. The methodological approach has enabled the three following sub-objectives to be reached: (1) map the multiple processes, (2) calculate the current PET bottle flows as well as the chosen environmental indicators, based on the given situation, then (3) evaluate the performance of alternatives constructed based on the territorial particularities. This study showed transportation is solely responsible for 0,2 % of GHG emissions attributable to the entire value chain. Conversely, the electricity mix, another spatial characteristic of territories, has a stronger influence on the GHG indicator. Some flows reallocations alternatives (towards territories with a lower electricity mix) permitted a decrease of the amount of equivalent CO2 emitted per bottle higher than 95 %, while simultaneously, flows distances have increased of 573 km (correspondingly 143 %). Nevertheless, when the electricity mix is low (about a few grams of equivalent CO2 per kWh of electricity), the impact of transportation on the carbon footprint is significant. In Quebec, transportation takes up more than 5 % of the PET bottle’s carbon footprint. The developed approach is presented as a decision-making tool to permit the consideration of territorial differences and highlight environmental opportunities.

Date	2 Dec 2022
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Mathias Glaus (Supervisor)