某碳质金矿石真空焙烧预处理工艺试验研究  

Experimental study on vacuum roasting pretreatment of a carbonaceous gold ore

作　　者：张辛未 宋永辉[1] 董萍 尹宁 李一凡 Zhang Xinwei;Song Yonghui;Dong Ping;Yin Ning;Li Yifan(Key Laboratory of Gold and Resources of Shaanxi Province,School of Metallurgical Engineering,Xi an University of Architecture and Technology;Shaanxi Institute of International Trade&Commerce)

机构地区：[1]西安建筑科技大学冶金工程学院,陕西省黄金与资源重点实验室 [2]陕西国际商贸学院珠宝学院

出　　处：《黄金》2022年第3期55-60,共6页Gold

基　　金：国家自然科学基金项目(51774227)。

摘　　要：某碳质金矿石总有机碳品位5.05%,矿石直接提金难度大。采用真空焙烧预处理—浸出提金联合工艺对其进行处理,研究了焙烧过程的影响因素及碳质金矿石中碳与硫的转化规律。结果表明:在磨矿细度-0.074 mm占75%、焙烧温度1200℃、保温时间10 min、升温速率7.5℃/min、再磨细度-0.074 mm占80%的条件下,金浸出率达到88.43%。真空焙烧过程中,金的主要包裹矿物硫化矿物发生分解反应使包裹金得以解离,矿石中61.25%的S元素最终以单质硫的形式挥发冷凝而非形成SO 2。有机碳发生热分解反应导致其“劫金”能力降低,固体产物中C元素高达90.00%,主要以单质碳的形式存在。真空焙烧预处理工艺可有效解决碳质金矿石中硫化矿物包裹及碳质物“劫金”问题,提高金浸出率,同时可降低有害气体处理成本。It is difficult to extract gold directly from the carbonaceous gold ore due to its 5.05%organic carbon grade.The joint process of vacuum roasting pretreatment and leaching is used for the treatment.The influence factors on roasting and the conversion rules of carbon and sulfur in carbonaceous gold ores are analyzed.The results showed that when grinding fineness of-0.074 mm accounts for 75%,roasting temperature is 1200℃,heat preservation time is 10 min,heating rate is 7.5℃/min,and regrinding fineness of-0.074 mm accounts for 80%,the gold leach-ing rate reaches 88.43%.In the process of vacuum roasting,pyrite,as the main gold-locking mineral,was decomposed,dissociating the locked gold,and 61.25%S element in the ore was finally volatilized and condensed in the form of elemental sulfur instead of forming SO_(2).The thermal decomposition of organic carbon reduces its"preg-robbing"ability,and the grade of C element in the solid product is up to 90.00%,which was mainly in the form of elemental carbon.The vacuum roasting pretreatment process could effectively solve the problems of sulfide locking and"preg-robbing"of carbonaceous matters in carbonaceous gold ores,improve the gold leaching rate,and reduce the cost of harmful gas treatment.

关 键 词：碳质金矿 真空焙烧 预处理 劫金 金浸出率 

分 类 号：TD953[矿业工程—选矿]