Cleaner Environmental Systems (Dec 2021)
Life cycle assessment for PET-bottle recycling in Brazil: B2B and B2F routes
Abstract
This study carried out the “cradle to the gate” Life Cycle Assessment (LCA) of two Polyethylene Terephthalate (PET) bottle recycling routes in a Brazilian context: 1) production of Post-Consumer Recycled PET (PET-PCR) by the bottle-to-bottle (B2B) process; 2) production of Recycled Polyester Fiber by the bottle-to-fiber (B2F) process. Primary data are all real data from a recycling unit in Minas Gerais State, Brazil – a highlight of this work; secondary data were given from the literature and LCA databases. The environmental impact indicators evaluated were: Global Warming Potential (GWP), Abiotic Resource Depletion (ARD), Terrestrial Acidification, Water Scarcity, Ozone Depletion Potential and Freshwater Ecotoxicity. Methodologies recommended for the Brazilian context were used for the impact assessment. A comparison between B2B and B2F was done: in five of the seven categories evaluated, B2F had a greater environmental potential impact; however, both show a lower impact than virgin PET. Related to similar products, results were compared with those of studies for other regions, for GWP and ARD, fossil, transportation characteristics such as average distance and load, resulting in impacts of the same order except when only transportation is analyzed. Environmental hotspots were related to diesel consumption in bottle logistics, and to the consumption of natural gas and electricity in industrial recycling processes. Improvement opportunities were identified, and proposals were discussed. The impact on changing bottle logistics was achieved by resizing PET-bottle bales, using more appropriate vehicles, and adopting transport distances compatible with international practice.