Mining Aluminum from Landfills: Challenges, Technologies, and the Case forPre-Landfill Intervention.

Aluminum, a critical mineral in modern industry and energy transition, presents substantial environmental and economic burdens when produced through primary methods due to its high energy consumption and associated emissions. Although secondary production through recycling offers significant energy and emissions savings, it is widely believed that a large volume of aluminum still ends up in Municipal Solid Waste Landfills, particularly in the form of used beverage cans (UBCs) and other post-consumer products. This paper explores the feasibility and challenges of recovering aluminum from landfills through landfill mining (LFM). It presents an in-depth review of the historical and current state of aluminum waste generation in the United States, highlighting the growing accumulation of aluminum in landfills and the limitations of existing recycling practices. The study evaluates the physiochemical conditions of landfills affecting aluminum stability and outlines key technologies for material recovery, including air classification, magnetic separation, eddy current separation, electrostatic separation, sink-float techniques, and optical sorting. Despite technological advances, the recovery of aluminum from landfills remains hindered by numerous barriers such as technical inefficiencies, contamination, oxidation, high operational costs, regulatory ambiguity, and public opposition. The findings emphasize the importance of pre-landfill aluminum recovery as a more viable and sustainable strategy. By diverting aluminum from disposal before landfilling, the environmental, economic, and logistical burdens of post-disposal recovery can be substantially mitigated. This review advocates for upstream integration of aluminum recovery into waste management systems as a pathway toward resource efficiency, landfill space conservation, and reduced reliance on energy-intensive primary production.