含铅固废还原固硫混合熔炼工艺研究

为解决湿法炼锌渣和废铅酸蓄电池铅膏等含铅固废难以经济有效回收利用的难题, 提出了一种含铅固废还原固硫混合熔炼新工艺。采用单因素试验分别考查了还原剂配比、碳酸钠配比、设定铁硅比FeO/SiO₂和钙硅比CaO/SiO₂等因素对熔炼效果的影响, 获得的最佳工艺条件为: 还原剂配比10%、Na₂CO₃用量4%、设定铁硅比1.4、钙硅比0.5, 在此条件下, 铅平均直收率为91.98%、渣含铅0.68%、锍含铅4.33%, 综合固硫率82.47%。该工艺流程短、清洁高效, 可实现一步炼铅和固硫熔炼。

Smelting Process with Reduction and Sulfur-Fixation for Lead-bearing Solid Wastes

In order to effectively recycle and utilize the lead-bearing wastes including zinc plant residues and spent lead-acid battery paste, a new smelting technique consisting of reduction and sulfur-fixation was proposed for study. With single-factor tests, effects of influencing factors, including the proportion of reductants, dosage of sodium carbonate, FeO/SiO₂ mass ratio and CaO/SiO₂ mass ratio on smelting were investigated. It is found that the following optimal conditions, including addition of 4% Na₂CO₃, 10% of reductant, FeO/SiO₂ mass ratio at 1.4, CaO/SiO₂ mass ratio at 0.5, resulted in the direct recovery rate of lead up to 91.98%, the content of lead in slag and ferric matte at 0.68% and 4.33% respectively, and a comprehensive sulfur fixation rate at 82.47%. It is shown that such method, being cleaning and efficient with a short technical process, can realize lead recovery and sulfur fixation by one-step smelting.