This study provides an effective solution to the recovery issue of hot acid leaching residue (lead-silver residue) from the hydrometallurgical process of Zn, in the form of low-temperature alkaline smelting. Investigations were carried out to study lead-silver residue as the raw material, sodium carbonate and salt as flux, carbon powder as the reductive agent, and the effects of salt usages, melting temperature, melting time, carbon powder usages, and sodium carbonate usage. The influence of relative factors was also verified. Under the optimum conditions, that is, using salt and sodium carbonate mass ratio as 4/6, melting time 60 min, temperature 900 ℃, carbon powder usage 0.15 times the raw materials, and sodium carbonate usage 1.215 times the raw materials, the average direct recovery of lead and silver reached up to 85.1% and 87.5%, and the average residual rate of lead and silver in the molten residue were 11.0% and 7.8%, respectively. The mechanism of immobilizing sulfur was also studied. The analysis of the XRD pattern showed that iron exists as Fe₃O₄, sulfur and zinc exist as ZnS, and lead and silver exist as crude lead. This method has one-step lead and silver recovery and sulfur immobilization.

本研究为湿法炼锌过程中热酸浸渣（铅银渣）以低温碱冶炼的形式回收问题提供了有效的解决方案。以铅银渣为原料，碳酸钠和食盐为熔剂，碳粉为还原剂，研究了食盐用量、熔化温度、熔化时间、碳粉用量、碳酸钠用量的影响。 . 还验证了相关因素的影响。在最佳条件下，即使用盐和碳酸钠质量比为4/6，熔化时间60 min，温度900℃，碳粉用量为原料的0.15倍，碳酸钠用量为原料的1.215倍，平均铅和银的直接回收率分别达到85.1%和87.5%，熔渣中铅和银的平均残留率分别为11.0%和7.8%。还研究了固定硫的机理。XRD图谱分析表明铁以Fe形式存在₃ O ₄、硫和锌以ZnS的形式存在，铅和银以粗铅的形式存在。该方法具有一步铅银回收和硫固定。