Element Distribution Behavior and Thermodynamics in Top-Blown Oxygen-Enriched Lead Smelting Processes

Based on industrial production data, the distribution patterns of elements in the oxygen-enriched top-blown Isa smelting process for lead were studied. The focus was on investigating the thermodynamic effects of different slag types and oxygen-enrichment levels on lead content in slag, and analyzing the equilibrium distribution of Pb, S, Fe, and Zn between slag and gas phases in different slag systems, thereby enabling the optimization of the smelting process and improving the lead grade in the slag phase. The optimized parameters obtained from simulation calculations were applied to the actual oxygen-enriched top-blown Isa lead smelting process. The results show that the most suitable smelting parameters are: CaO content of 3.5–4%, SiO2 content of 5.5–6%, SiO2/Fe ratio of approximately 0.9, CaO/SiO2 ratio of approximately 0.3, and oxygen-enrichment level maintained at around 60%. Under these conditions, the lead grade in the slag phase is approximately 50%, representing a relative increase of about 8% compared to that before optimization.