Cleaner Engineering and Technology (Feb 2022)
Comparative life cycle analysis of disposable and reusable tableware: The role of bioplastics
Abstract
Annually, 115.000 tons of plastic tableware are used in Italy. The end of life of these objects is particularly troubled because no efficient way of recycling or reusing exist. Studies performed by the European Union demonstrate that about 80% of sea waste is made of plastic, representing a danger to human health and ecosystem. The aim of this paper is to analyse substitutes to disposable plastic tableware using the Life Cycle Assessment methodology. The alternatives are objects made of bio compostable plastic, both disposable and reusable. This article compares single-use and multi-use tableware made of a Polylactic acid (PLA) - Polybutylene succinate (PBS) blend with traditional disposable tableware made of polypropylene and of polystyrene. In order to perform an effective assessment, the objects are grouped in place settings, each made of a cup, a plate and cutlery. The use of tray mat and napkin is also taken into account. It was assumed that the fossil-based items are sent to landfill whereas the bio-based ones are sent to a compost plant. The functional unit chosen was “the service of 1000 meals”. The impact categories taken into account are Global Warming 100a, Ozone Depletion, Ozone Formation (Vegetation), Acidification, Aquatic Eutrophication, Human Toxicity water and Ecotoxicity water chronic. The results show that the compostable table sets have lower impact than the sets made of fossil-based plastic in all the categories except in Ozone Depletion and in Aquatic Eutrophication. In the categories of Human Toxicity water and Ecotoxicity water chronic, fossil-based materials have higher impact than multi-use one mainly due to the landfill scenario chosen as end of life. Disposable and reusable systems give a different contribution to total impact in different life stages. For disposable systems, the production and the end of life are the critical stages in terms of environmental burden, whereas for reusable systems washing is the most impactful phase. Further improvements can be obtained in the production of bio-based materials by using renewable energy to power the facilities whereas the washing phase can be improved by adopting certified ecopower. The impact of the reusable system strongly depends on the assumptions made on the number of reuses and on the washing modality.
