Municipal waste life cycle assessment part 1, and aluminium case study

Life Cycle Assessment (LCA) is essentially a material and energy balance over the entire life cycle of a material, product or service to determine its interaction with its environment and to assess its impact on the environment. Most LCAs have so far been of specific consumer products. This paper develops a method for LCA of the base materials, which are derived from many different products, in municipal waste. The method quantifies the environmental impact of all stages in the life of a material: production, product manufacture and use, and waste disposal. It includes impacts apportioned from general industrial processes, such as transport and electricity generation. Measures of specific environmental impacts, for example SO 2 emissions and NO X emissions, are aggregated wherever possible into environmental loads, in this case units of polluted air. Recycling is widely believed to reduce the burden of product life cycles on the environment. However, consideration of the additional loads due to the extra operations needed to recycle material often casts doubt on this belief. The method is designed for comparing the environmental loads of various rates of material recycle with the other waste management options of landfill and incineration. The method is applied to aluminium. It is shown that recycling aluminium considerably reduces all the environmental loads considered, compared to landfill and incineration.