酸浸提高金氰化浸出率的试验研究

对于含砷较高的金矿，在研究和生产实践中多采用二段焙烧技术进行预处理，通过除砷和除硫来获得较高的金浸出率。如何通过采用更低成本的预处理方法来进一步降低尾渣的含金量，是目前研究和生产实际中亟待解决的技术难题之一。在对某二段焙砂进行化学分析、矿物组成及金赋存状态分析的基础上，进行了强酸浸出提高金氰化浸出率的试验研究，着重探讨了磨矿粒度、浓硫酸用量、浸出温度和浸出时间对金氰化浸出率的影响。试验结果表明：在二段焙砂球磨1 h，每吨二段焙砂的浓硫酸用量为2 t，酸浸反应温度为95 ℃以及浸出时间为2.5 h的条件下，金的氰化浸出率可达97.86%。

Experimental Study on Raising the Cyanide Leaching Efficiency of Gold by Acid Leaching

For high arsenic containing gold ore，two stage roasting technology for pretreatment in the research and production practice are usually used to obtain higher leaching rate of gold by removing arsenic and sulphur.The key technical problem should be resolved urgently in the research and production is how to adopt low-cost pretreatment method to further reducing the rate of gold in tailing.The research on raising the cyanide leaching efficiency of gold by acid leaching was carried out on the basis of chemical analysis，mineral composition analysis and the gold occurrence state analysis of the second segment calcine.The effects of experimental conditions，such as the grinding size， the volume of concentrated sulfuric acid，leaching temperature and leaching time were investigated.After being milled for 1 hour，the second segment calcine was leached at 95 ℃ for 2.5 hours by using concentrated sulfuric acid dosage 2 tons per ton（to second segment calcine），and the cyanide leaching efficiency 97.86% of gold was achieved.