From the point of view of sustainable development, improving waste management is essential if society’s environmental impacts are to be reduced. Identifying waste management channels with lower environmental impacts is thus a key issue. The waste hierarchy illustrated in Figure 1 is often used as a rule of thumb followed by public policies.
However, a recurring theme in the debates that surround waste and resources management is the extent to which the recycling of materials offers genuine benefits to the environment. Often, critics of the policy drive towards greater recycling assert that the act of recycling may in fact have little or no benefit to the environment, suggesting that more energy may be used in getting materials to the recycling facility than is saved by the process of recycling.
In order to compare waste management routes in environmental terms, the Life Cycle Assessment (LCA) methodology is currently seen as the best approach to use. The strength of LCA is that the methodology allows comparison of two or more different products or processes by quantifying the service given by the products or processes.
The weakness of LCA is that the results of the assessment are very sensitive to the scope of the study, to the hypothesis made, etc. To compare environmental impacts of numerous waste management routes, one solution is to review and compare existing Life Cycle Assessment (LCA) studies on waste management and to analyse the impacts of each hypothesis. To analyse the different burdens or benefits of each waste management option, WRAP (Waste & Resources Action Programme) reviews and commissions relevant LCAs. The purpose of this study is to update the Environmental Benefits of Recycling published by the WRAP in 2006.
This study reviews LCA studies and compares the various possible options for waste management. This study was undertaken by Bio Intelligence Service (BIOIS) and the Copenhagen Resource Institute (CRI, former Danish Topic Centre on Waste and Resources). Collaboration with WRAP took place throughout the study. Materials covered by this study are paper and cardboard, plastics, biopolymers, food and garden waste, wood and textiles.
The waste management options that are studied are composting, energy recovery (incineration, anaerobic digestion, pyrolysis and gasification), landfill and recycling.
Table 1 shows the combinations of
materials and treatment options covered in the study (the combinations materials/disposal options included in the
previous edition are highlighted in grey). Some options, such as gasification or pyrolysis, could in theory be used
for most of the fractions but the literature review has pointed out large data gaps, therefore these options could
not be assessed.
