(1、广东省环保局废物管理中心，广州 510045
2、昆明理工大学真空冶金研究所，昆明 650093)
摘 要: 为克服粗铋精炼中，传统的加锌除银工艺存在的 效率低、污染环境等问题，提出了用真空蒸馏，将铋蒸馏、冷凝，银残留在蒸馏渣中的脱银工艺。实验研究表明，粗铋的真空蒸馏脱银在温度约1 050℃和 约30 Pa真空条件下 ，经过两次一级蒸馏或一次两级蒸馏，使铋中含银量达到低于5×10-4 %的要求。据实验结论设计的内加热闭式多级连续粗铋真空蒸馏炉，具有进出料方便、炉况稳定、热效率高、自动控制和对环境无污染等优点。
关键字: 粗铋 真空蒸馏 脱银
（1.Waste Management Centre, Guangdong Provincial Environmental Protecting Agency, Guangzhou 510045 ;
2.Vacuum Metallurgy Institute, Kunming University of Science and Technology, Kunming 650093）
Abstract:In order to improve the traditional Parkes method of desilverization (zinc desilverization) for fining crude bismuth, the new technique of desilverization by vacuum distillation, in which bismuth is distilled and then condensed but silver remains in residue, has been investigated. The experimental results showed that under the following conditions, e.g. distillation temperature about 1 050℃, vacuum pressure about 30 Pa and either twice one-grade distillation or once two-grade distillation, the silver content in crude bismuth could be reduced to below 5×10-4%. A multistage inter-heating closed vacuum furnace was roughly designed based on the experimental results. The designed furnace can be used for continuous production, and also has the advantages of the convenience for feeding and outlet of material, high heat efficiency and no pollution.
Key words: crude bismuth vacuum-distillation desilver
