金矿氰化浸出强化技术研究

本文分析研究了氰化浸出理论,从助浸剂、浸出设备、浸出工艺等方面总结了金矿氰化浸出强化技术的研究现状,提出了金矿氰化浸出强化技术的发展方向。     

山东某金矿氰化浸出过程中影响因素的研究

通过对山东某金矿浮选精矿的氰化浸出研究 ,探讨了影响金矿氰化浸出的因素。研究结果表明 :通过优化金矿氰化浸出的各种因素 ,可提高矿浆中的“有效溶解氧”,改善氰化浸出环境 ,提高浸出速度 ,缩短氰化浸出时间 ,降低氰化物用量 ,提高金矿氰化浸出效果     

难选冶金矿微波预处理研究

研究难选冶金矿固体和矿浆微波预处理过程及微波预处理后氰化浸出效果，并分析微波预处理过程机理。矿样A固体状态下通过微波预处理，金的氰化浸出率达86．50％-89．19％，矿样B矿浆通过微波预处理，金的氰化浸出率达96．69％-97．86％。研究结果表明，微波预处理过程加热快而且均匀，处理时间短、成本低。微波预处理技术为难选冶金矿预处理的有效枝术之一。     

哈德门金矿富氧炭浸提金工艺的研究及应用

在开放体系下充氧对哈德门金矿进行富氧氰化浸出小型试验及工业实践证明，富氧氰化浸出明显地提高黄金氰化浸出速度，浸出时间缩短一半，从而处理能力提高一倍，节省基建投资402.78万元，年利润增加103.6万元，经济效益显著。     

哈德门金矿富氧炭浸提金工艺的研究及应用

在开放体系下充氧对哈德门金矿进行富氧氰化浸出小型试验及工业实践证明，富氧氰化浸出明显地提高黄金氰化浸出速度，浸出时间缩短一半，从而处理能力提高一倍，节省基建投资４０２．７８万元，年利润增加１０３．６万元，经济效益显著。     

高砷高硫金精矿提金工艺研究

介绍了某金矿氰化尾矿的摇床重选精矿的物质组成研究和多种提金工艺研究。研究结果表明，不利于金的直接氰化浸出的原因是硫化物包裹金占有率高，浸出的有害杂质As、Cu、Bi、Sb含量较高，与Au关系密切，相互胶结和共生，沸腾炉焙烧后，焙砂As、Se脱除率高，金属硫化物基本上完全转化为疏松多孔状的铁氧化物，提高了金的浸出率，金的浸出率达96.95%，认为是适合于处理某金矿氰化尾矿的摇床重选精矿的提金工艺。     

金矿氰化浸出助浸剂的研究

介绍了柠檬酸作氰化浸出助浸剂,分别对罗山金矿浮选精矿、鹿尔坝金矿焙砂、鹰嘴山北金矿进行助浸试验的结果。研究结果表明,柠檬酸作为助浸剂可改善氰化浸出环境,提高浸出速度,缩短氰化浸出时间,降低氰化物用量。     

难处理金矿石选冶技术研究

甘肃某金矿金矿品位较低,矿石氧化程度较高。金矿物粒度细小,主要以微粒、次显微金矿物形式嵌布于褐铁矿粒间以及被粘土矿物充填的褐铁矿裂隙、孔洞中,属于难处理矿石。根据该矿石性质进行了原矿全泥氰化浸金和浮选富集-氰化浸金两种工艺流程的试验研究,结果表明该两种工艺均可获得较好的选矿指标:原矿全泥氰化搅拌浸出的金浸出率为94.19%;浮选富集-氰化浸金的金浸出率为97.62%,银浸出率为90.80%。由于浮选抛尾可显著提高氰化浸金的设备效率和经济效益,故推荐浮选富集-氰化浸金为该金矿的选冶技术方案。     

药剂预处理金精矿氰化工艺研究与实践

对河台金矿金精矿氰化工艺，通过采用药剂X预处理的方法，提高了氰化浸出速度，优化了相关作业条件，增加了氰化处理能力。同时该法使用后，降低了材料消耗与处理成本，提高企业经济效益。     

湖南塘家冲红土型金矿矿石氰化浸出工艺试验研究

重点阐述了对湖南塘家冲红土型金矿矿石进行的氰化浸出试验研究的合适参数和工艺条件,浸出工艺试验结果表明:氰化浸出工艺浸出剂浓度、氧化剂浓度、液固比、溶液pH值、浸出时间等对浸出效果有较大的影响,选择合适的参数和工艺条件,金浸出率将达90%以上,为下步工业试验和工业生产提供参考依据.     

A kinetic and electrochemical study of the ammonia cyanide process for leaching gold in solutions containing copper

One of the biggest challenges for the gold industry in the 21st century is the presence of copper in gold containing ore bodies. This is because copper consumes large quantities of cyanide. In addition, copper cyanide species are more stable than free cyanide, and hence are problematic in events of tailings spillage. One of the methods which has been suggested for treating copper containing ores is to leach with an ammonia cyanide solution. The effect of copper and ammonia addition on gold leaching kinetics was studied in the present paper. It will be shown that when the solutions do not contain copper, the addition of ammonia decreases the rate of gold leaching. When copper is added to solution, the leach rate does decrease due to the formation of the copper cyanide complexes. However it will be shown that under conditions of zero free cyanide, gold does leach readily via the Cu(CN)₃²⁻ complex. It was found that the addition of ammonia had little effect on the leaching of gold by Cu(CN)₃²⁻, but did increase the leaching kinetics when the major cyanide species present is Cu(CN)₂⁻. Under these conditions, leaching in the absence of ammonia is very slow. The effect of copper(II) addition was also studied, and it was found that in the absence of free cyanide the presence of copper(II) increases the leach rate, provided there is enough ammonia to stabilise it against reaction with the copper(I) cyanide complexes.     

某难选金矿的选矿试验研究与工艺流程改造

甘肃某金矿金矿物主要为自然金,金属矿物主要为黄铁矿、毒砂、褐铁矿、辉锑矿。金矿物中24.88%的金以次显微或微细包裹体形式赋存于黄铁矿、毒砂等硫化矿物中,10.87%的金以微细包裹体形式赋存于褐铁矿、锑铁矿及石英等脉石矿物中。针对该微细粒浸染含砷含锑的金矿石,通过详细的条件试验及不同流程结构的试验研究,采用浮选+中矿再磨氰化浸出的选矿工艺流程,得金精矿金品位50.21g/t,金总回收率78.81%,实现了较高的金回收率。      

高硫金细粒嵌布硫化矿金矿石选冶工艺的探讨

本文结合小型试验研究结果, 对高硫金细粒嵌市硫化矿金矿石选冶工艺进行了探讨。处理该类型金矿石比较适用的生产工艺是: 混合浮选-混精氰化浸出-氰渣硫酸化焙烧制酸-硫酸渣氰化浸出。     

含铜氧化金矿氨氰选择性提金试验研究及工业应用

针对含铜氧化金矿采用氨氰选择性浸出提金,考察了分段加药制度、硫酸铵用量、矿石粒度等对金浸出率及浸出液铜金比的影响。结果表明:当硫酸铵用量8.00 kg/t,氰化钠用量0.60 kg/t,石灰用量5.00 kg/t,矿浆浓度40.00%,磨矿细度-0.074 mm粒级含量不低于95.00%时,平均金、铜浸出率分别为86.66%和1.16%。工业试验连续运行70 d,氰化尾渣金品位约0.55 g/t,金吸附率99%,金解吸率99.2%,电积回收率99.5%,金精炼回收率99.5%,金锭纯度99.99%,产品金达到国标Au-1标准。     

A review of copper cyanide recovery technologies for the cyanidation of copper containing gold ores

Many gold producers are today processing gold ores containing significant amount of cyanide soluble copper. Typically, cyanide destruction is used to prevent the discharge of copper cyanide into tailings storage facilities. This imposes a significant financial cost to producers from the additional cyanide used to solubilize the copper and the cost of cyanide destruction reagents. Therefore, the recovery of copper as a valuable by-product and the recycle of cyanide to the leach circuit have the potential for significant economic and environmental benefits. This includes enabling the treatment of gold ores with even higher soluble copper. Over the years, a variety of processes have been developed or proposed to recover the copper and/or cyanide including acidification based technologies such as AVR and SART, direct electrowinning, activated carbon, ion exchange resins, solvent extraction, polychelating polymers, and membrane technologies. In this paper, these processes are critically reviewed and compared, with particular focus on the advantages and limitations, and the separation of copper from cyanide. Ultimately, there is no universal process solution and the choice is highly dependent on the nature of the stream to be treated and integration with the whole processing plant.     

铊离子强化金精矿氰化浸出的研究

通过对混合电位模型的研究, 提出了铊离子对金氰化溶解只有在辅以阴极强化的条件下才具有显著强化作用的观点。以某硫化物金精矿为对象进行的强化氰化浸出试验表明, 不加入辅助氧化剂时, 铊离子对氰化浸金的强化作用并不显著;加入H₂O₂作为辅助氧化剂时, 取得了显著提高金浸出率的效果。对于常规氰化浸出48 h 只有54.89 %金浸出率的金精矿, 采用铊离子和H₂O₂ 协同强化时, 经过一段4 h 、二段12 h 总共16 h 的两段浸出, 即可达到92%以上的金浸出率。     

Processing of gold ores using Guinean bauxite waste

This paper describes the treatment of gold ores via the bauxite waste mud used as a pH modifier in the cyanidation of gold. The red mud is irrefutable in modifying the pH of gold ore sludges. So any gold contained in the red mud is concentrated by gravity separation and is recovered along with gold from the gold ore. Carbon tests are carried out on cyanide leach solutions to determine the level of deactivation resulted by organics in the bauxite waste mud.     

The mechanism of leaching of gold from refractory ores

Refractory gold ores commonly contain free gold, submicroscopic gold, base metal sulphides, pyrite, pyrrhorite, labile sulphides and carbonaceous material. The analysis of gold deportment with the diagnostic leaching technique has opened a research field to gain more insight into the fundamentals of the kinetic behaviour of gold dissolution from refractory ores. Hence, more detailed studies on the kinetics of the reactions that occur during leaching with cyanide are now possible.Previous research work has indicated that the dissolution rate of gold during cyanidation becomes depressed after a certain time with no further increase in the rate. However, a second noticeable increase in the gold dissolution rate has been observed after a leaching time of 5 to 12 hours during some of the cyanidations, following the destruction of a mineral with the diagnostic leaching technique. If such a second increase in dissolution rate does not occur, the re-leaching of the filtered solids with a fresh cyanide solution yields an additional gold extraction of 4 to 8 %.Various experimental results have indicated that a passivative film forms on the surface of some of the liberated gold. The selective destruction of the various minerals with oxidative acid leaches destroys and/or decomposes certain minerals which may form films on the gold surface by precipitation. The chemical composition of these films and precipitates depends on the mineralogy of the sample. These films may be oxides, sulphides, carbonates and cyanide complexes.The complexes can be destroyed, depending on the nature of the film, by interstage dilute acid and/or cyanide washes in an agitated vessel. The destruction of the films exposes the gold surface for cyanidation. Whereas most of the previous studies on the leaching of gold have focused on the whole ore, the emphasis in this study was on the leaching behaviour of gold from various ore constituents. This approach of studying the leaching behaviour of different gold bearing minerals has provided reasons why some ores leach better than others.     

The cyanide leaching of gold in solutions containing sulfide

A large proportion of the gold processed in the 21^st century will be recovered from sulfide ores. Since the sulfide minerals are to some extent soluble in cyanide solutions, there will always be some sulfur species present in the leach solution. It has been shown that soluble sulfide hinders the rate of gold leaching, forming a protective layer of the type Au/S_x. Electrochemical studies of the constituent half reactions: gold oxidation; and oxygen reduction, were consistent with this view. The effect of sulfide and cyanide concentrations on the leaching reaction were investigated, and it was shown that the sulfur formed is chemically attacked by cyanide, resulting in higher leach rates at higher cyanide concentrations. The effect of lead was also studied and is discussed in detail.