An environmental analysis for comparing waste management options and strategies

The debate on different waste management practices has become an issue of utmost importance as human activities have overloaded the assimilative capacity of the biosphere. Recent Italian law on solid waste management recommends an increase in material recycling and energy recovery, and only foresees landfill disposal for inert materials and residues from recovery and recycling. A correct waste management policy should be based on the principles of sustainable development, according to which our refuse is not simply regarded as something to eliminate but rather as a potential resource. This requires the creation of an integrated waste management plan that makes full use of all available technologies. In this context, eMergy analysis is applied to evaluate three different forms of waste treatment and construct an approach capable of assessing the whole strategy of waste management. The evaluation included how much investment is needed for each type of waste management and how much ‘utility’ is extracted from wastes, through the use of two indicators: Environmental yield ratio (EYR) and Net eMergy. Our results show that landfill is the worst system in terms of eMergy costs and eMergy benefits. Composting is the most efficient system in recovering eMergy (highest EYR) from municipal solid waste (MSW) while incineration is capable of saving the greatest quantity of eMergy per gram of MSW (highest net eMergy). This analysis has made it possible to assess the sustainability and the efficiency of individual options but could also be used to assess a greater environmental strategy for waste management, considering a system that might include landfills, incineration, composting, etc.