Comparative life cycle assessment and life cycle costing of four disposal scenarios for used polyethylene terephthalate bottles in Mauritius

Abstract

The annual rise in population growth coupled with the flourishing tourism industry in Mauritius has lead to a considerable increase in the amount of solid waste generated. In parallel, the disposal of non-biodegradable wastes, especially plastic packaging and plastic bottles, has also shown a steady rise. Improper disposal of used polyethylene terephthalate (PET) bottles constitutes an eyesore to the environmental landscape and is a threat to the flourishing tourism industry. It is of utmost importance, therefore, to determine a suitable disposal method for used PET bottles which is not only environmentally efficient but is also cost effective. This study investigated the environmental impacts and the cost effectiveness of four selected disposal alternatives for used PET bottles in Mauritius. The four disposal routes investigated were: 100% landfilling; 75% incineration with energy recovery and 25% landfilling; 40% flake production (partial recycling) and 60% landfilling; and 75% flake production and 25% landfilling. Environmental impacts of the disposal alternatives were determined using ISO standardized life cycle assessment (LCA) and with the support of SimaPro 7.1 software. Cost effectiveness was determined using life cycle costing (LCC). Collected data were entered into a constructed Excel-based model to calculate the different cost categories, Net present values, damage costs and payback periods. LCA and LCC results indicated that 75% flake production and 25% landfilling was the most environmentally efficient and cost-effective disposal route for used PET bottles in Mauritius.