The Potential Benefits of Introducing Informal Recyclers and Organic Waste Recovery to a Current Waste Management System: The Case Study of Santiago de Chile

摘要

Chile has experienced rapid economic growth in recent decades. However, this economic growth has been accompanied by a huge increase in waste generation. Although the country has historically put emphasis on appropriate final disposal of waste through landfill, the environmental problems generated by this activity have shown that it is necessary to improve the national solid waste management approach. Santiago, the capital of Chile, generates about 43% of the national solid waste. A study conducted by the Ministry of the Environment in 2011 found that 14% of the waste generated in the capital is recycled, mostly thanks to local campaigns and collection by the informal sector (scavengers). While in 2009 the government set a target to recycle 25% of municipal inorganic waste by 2020, there is no information on the implementation process to reach this target. Most importantly, the law has not established specific recycling rates for target materials, and, has not taken into consideration organic waste recovery, which accounts for 48% of the total waste stream. In order to meet the government target and at the same time promote organic waste recovery, this study proposes and evaluates the environmental impacts of different viable alternatives for municipal solid waste collection, treatment and recovery by using Life Cycle Assessment (LCA). The proposed scenarios range from the current situation to the introduction of organic waste recovery and the inclusion of informal recyclers in the collection process. By considering the investment and treatment costs of each alternative, the study identifies the most effective scenario in terms of avoided pollutants per cost ratio. Finally, the study analyzes the feasibility of the implementation of the selected scenario by indicating benefits and challenges. The results of the scenario evaluation suggest that the scenario with the highest recovery of inorganic and organic materials, coupled with the participation of the informal collectors, will have a positive impact not only in terms of meeting and surpassing the government goal, but also in the reduction of CO 2 eq emissions. This scenario can reduce by approximately 3.5% the national CO 2 eq generated, with a cost of $14.1/ton. Moreover, the potential reductions of CH 4 account for 8.5% of the national CH 4 emissions and 24.5% of the national waste sector CH 4 emissions.