焙烧氰化尾渣提金工艺研究现状

焙烧氧化过程中铁物相出现熔融或再结晶，对金造成二次包裹，使焙砂中部分金仍难以浸出，导致焙烧氰化尾渣金品位较高。破坏尾渣中铁氧化物对金的包裹可提高金的浸出率。综述了焙烧氰化尾渣主要提金工艺，包括直接酸溶法、还原焙烧法、氯化法、炼铁-电解法、硫酸熟化法和硫脲法等。直接酸溶工艺简单，金浸出效果较差；还原焙烧法金浸出率高，但工艺复杂、能耗大；氯化焙烧法对矿石适应性强，可综合回收有价金属，但基建及维护费用高；炼铁-电解法在富集金的同时可获得纯铁产品，对矿石有较高的要求；硫酸熟化法显著提高金银浸出率，与直接酸溶法相比，所需更高的温度与酸度；硫脲法反应速率快、选择性好，但生产成本较高。 关健词:有色金属冶金；氰化尾渣；铁氧化物；包裹金；提金

Research Status of Gold Extraction Process of Roasting Cyanide Tailings

During the roasting oxidation process, the iron phase appears to melt or recrystallize, causing secondary encapsulation of gold, making it difficult for some gold in the calcined to be leached, resulting in higher gold grade in roasting cyanide tailings. Destroying iron oxide in the tailings can increase the leaching percentage of gold. The main gold extraction processes of roasting cyanide tailings were reviewed, including direct acid dissolution, reduction roasting, chlorination, iron making-electrolysis, sulfuric acid ripening method and thiourea method. The direct acid dissolution process is simple, but the gold leaching effect is poor. The reduction roasting method has high gold leaching percentage, but the process is complicated and the energy consumption is high. The chlorination roasting method has strong adaptability to ore and can comprehensively recover valuable metals, but infrastructure and maintenance costs high. The iron-electrolysis method can obtain pure iron products while enriching gold, which has higher requirements on ores. The sulfuric acid ripening method significantly increases the leaching percentage of gold and silver, and requires higher temperature than direct acid dissolution. Thiourea method has a fast reaction rate and good selectivity, but the production cost is high.