Innovative integration of superimposed extrusion with supergravity for enhanced metallic aluminum recovery from hot dross

Aluminum dross, a valuable resource rich in metallic aluminum, presents a significant challenge: conventional methods fail to efficiently liberate entrapped metal from its complex matrix. Here, we introduce an innovative technique combining superimposed extrusion with supergravity separation, dramatically enhancing the recovery of aluminum droplets from dross. We first characterized the distribution and microstructure of aluminum particles within the dross. Systematically investigating the influence of gravity coefficient (G) and extrusion force (F) then revealed their critical role in separation efficiency across particle sizes. Under optimized conditions (G = 500–700, F = 1000–1300 N), we achieved a remarkable total metallic aluminum recovery of 95.78%. Successful pilot-scale validation using hot aluminum dross further demonstrated the method's robustness, yielding a high recovery of 94.88%. This work establishes a novel, highly efficient pathway for reclaiming metallic aluminum from hot dross, substantially advancing the resource utilization of this industrial byproduct.