Aluminum is a critical mineral for the transition to a low-carbon future through its use in manufacturing of solar panels, wind turbines, and electric cars. One method to secure US supply chains is to recover aluminum from waste streams. According to the EPA, 16.69 million metric tons of aluminum was disposed of in US landfills from 1960 to 2018. With an annual consumption rate around 4 million metric tons per year, recovering even a fraction of the landfilled aluminum would represent a major new supply stream. Copper is another critical mineral for energy which is present in US landfills. In this report, we present an assessment of mining aluminum and copper from an old landfill (25+ years post-closure). Excavated materials are first separated through a trommel screen which recovers the cover soil. A magnetic separator and eddy current is then used to recover the ferrous and aluminum/copper metals from the remaining municipal solid waste (MSW). The aluminum/copper stream is then shredded and separated through air classification. The ferrous, aluminum, and copper products are all sold to scrap metal buyers off-site. The remaining MSW with no value is sent off site for disposal in another landfill. The value of the space made available from landfill excavation, for future waste disposal, redevelopment, stormwater management, or other uses are also considered. This developed framework was used to build a life cycle assessment and techno-economic model of aluminum recovery from municipal solid waste (MSW). Key reported metrics are the cumulative expenses and revenues for a model landfill excavation site, cost per kg recovered aluminum, as well as the kg of equivalent CO2 emissions (CO2eq) per kg of recovered aluminum. It was found that both the economic and environmental feasibility of landfill mining for aluminum and copper primarily depends on the characteristics of the landfill site, the quality of the recovered aluminum and copper, and the desired use for the reclaimed land.
