Thermal media-reconstructed heat transfer pathways and mechanisms elucidation for molten copper slag

Improving the cooling efficiency of molten copper slag (MCS) is critical for the green transformation of the metallurgical industry. However, the poor thermal conductivity of MCS induces inevitable issues, including heat accumulation, prolonged cooling durations, and low recovery efficiency of valuable metals during natural cooling. Herein, we proposed a novel strategy to reconstruct the heat transport pathways in MCS using thermal media and adopted the proper orthogonal decomposition (POD) reduced-order model to elucidate the heat transfer and cooling characteristics. The results demonstrate that the thermal media could achieve reductions of 10.6% in average temperature and 81.8% in liquid fraction, which is attributed to the formation of a continuous heat transfer pathway with a high-temperature gradient within MCS. Moreover, a quantitative correlation model between structural parameters and cooling performance was developed, enabling rapid prediction of the cooling process and determination of the thermal media structural parameters. Furthermore, POD-based modal analysis revealed that the first-order modal energies of the temperature and liquid fraction fields shifted toward higher-order modes by 2.05% and 1.51%, respectively, indicating the internal heat transfer and solidification front transition from single-wall domination to multi-channel synergistic advancement, thereby realizing the reconstruction of heat transport pathways. These findings offer novel insights and a design basis for the efficient cooling and process optimization of MCS.