(1、廣東省環(huán)保局廢物管理中心，廣州 510045
2、昆明理工大學真空冶金研究所，昆明 650093)
摘 要: 為克服粗鉍精煉中，傳統(tǒng)的加鋅除銀工藝存在的 效率低、污染環(huán)境等問題，提出了用真空蒸餾，將鉍蒸餾、冷凝，銀殘留在蒸餾渣中的脫銀工藝。實驗研究表明，粗鉍的真空蒸餾脫銀在溫度約1 050℃和 約30 Pa真空條件下 ，經(jīng)過兩次一級蒸餾或一次兩級蒸餾，使鉍中含銀量達到低于5×10-4 %的要求。據(jù)實驗結論設計的內(nèi)加熱閉式多級連續(xù)粗鉍真空蒸餾爐，具有進出料方便、爐況穩(wěn)定、熱效率高、自動控制和對環(huán)境無污染等優(yōu)點。
關鍵字: 粗鉍 真空蒸餾 脫銀
（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
