焙烧-氰化工艺中含氰废水处理新方法的研究与应用

研究提出了一个焙烧-氰化工艺中含氰废水处理的新方法。试验表明,该工艺方法不但可回收有价金属,有效地利用废水中的氰化物,且能够提高金、银的氰化浸出率,实现了闭路全循环、含氰废水零排放的目的。在国内解决了焙烧-氰化工艺中含氰贫液闭路全循环的难题,其经济效益和社会效益非常显著。     

全泥氰化炭浆提金工艺含氰尾矿处理技术改造与实践

介绍了一种全泥氰化炭浆提金工艺含氰尾矿处理技术新工艺方法。该方法基于采用压滤机将含氰尾矿浆压滤进行固液分离，滤饼送至尾矿库堆放，滤液用锌粉置换回收金、银；置换后的尾液采用酸化中和法处理。回收重金属离子，含氰废水返回流程利用。生产实践表明。该工艺不但综合回收尾液中的金、银、铜等有价元素，实现了含氰废水闭路循环。而且节约了处理成本。解决了尾渣的堆放难题和环境污染，具有极大的经济效益和社会效益。     

氰化污水零排放工艺研究与应用

氰化污水零排放工艺的研究结果表明,酸化－－沉淀－－碱中和后废水全循环为氰化工艺提供了良好的技术条件,同时可回收有价金属,降低氰化物消耗,实现含氰废水零排放,并取得了较好的经济效益和社会效益。     

国外信息

微波辅助氧化从含硫氰酸盐溶液中回收氰化物贵金属提取通常是使用过量的氰化物从矿石中浸出金和银。氰化物消耗往往是总生产成本中最重要的组成部分。目前,从硫氰酸盐和热力学性质稳定的氰络合物中回收氰化物工艺在工业上已经应用。但是,有许多生产厂家,还在采用成本较高的氰化     

氰化物污染及其治理技术（续三）

氰化物污染及其治理技术（续三）高大明（冶金工业部长春黄金研究院）３含氰废水的来源与特点人们常说的含氰废水并不是指含（ＣＮ）２的废水，而是泛指含有各种氰化物的废水。黄金氰化厂产生的含氰废弃物不仅包括含氰化物的废水（澄清的贫液、氰尾液、滤液和澄清水），还...     

酰基化强碱性离子交换纤维制备及其对金属氰络合物吸附性能研究

氰化提金工艺产生的含氰废水中多含有金属氰络离子,其会消耗额外的氰化物,进而影响生产工艺指标.研究以聚丙烯纤维为基体,制备了酰基化强碱性离子交换纤维(ASA-IEF),并考察了其对废水中金属氰络离子的去除性能.ASA-IEF的最优制备条件为反应时间4 h、反应温度30℃、三氯乙酰氯与苯乙烯摩尔比1:1.2.在此条件下,纤...     

氰化尾液除铜 提高金氰化浸出率实践

松树南沟金矿氰化厂尾液含铜高,耗氰量大,金浸出率达不到设计指标。为解决这个问题,进行了长时间的试验研究。根据试验结果,采用两步沉淀法除铜、尾液全循环工艺,并进行了工业试验。试验结果表明,采用该工艺可以从氰化尾液中回收铜,提高金氰化浸出率,实现氰化尾液全循环。     

焙烧氰化尾渣综合利用与新工艺探讨

氰化尾渣是难处理金矿经焙烧氰化浸出后的产物,含有金、银、铁等有价金属及微量氰,必须对其进行无害化处置和资源化利用。焙烧过程由于部分铁物相发生熔融或再结晶,导致部分金被致密赤铁矿二次包裹,要回收其中的金,最有效的途径是破坏包裹金的赤铁矿。在分析现有氰化尾渣无害化处置方法以及破坏包裹金赤铁矿方法研究与工艺应用现状的基础上,针对现有工艺将氰化尾渣无害化处置和除铁两工序分开的弊端,提出将氰化尾渣除铁和脱氰两过程合并进行以及浸出液光催化降解氰的新工艺,并对新工艺进行探索研究。     

提金氰化物回收循环再用技术新进展

从提金含氰废水中回收利用氰化物是比氧化消除或破坏氰化物以达到排放标准更科学更经济的方法, 着重介绍了现有酸化法(AVR ) 工艺的新进展, 即新型AVR、MNR、SART 及Velardena 工艺原理及工艺过程。简述了用离子交换树脂吸附法、活性炭法、萃取法回收氰化物新技术及氰化废水全循环零排放技术。国内外研究动向分析表明, 氰化物回收循环技术是经济有效的、面向21 世纪初期可持续发展的黄金冶金绿色工程组成部分, 具有重大经济、社会及环境效益。     

金精矿浸出含氰废水综合处理的研究与工业实践

处理金精矿浸出含氰废水一般采用酸化回收法，氰化物的去除率只能达到90％左右，给二次处理增加了技术与经济上的难度。文中从提高酸化回收法的氰化物去除率入手，研究改进了金精矿浸出含氰废水综合处理的工艺及设备，使氰化物的去除率达到99％以上，为二次处理创造有利条件。采用二氧化硫－空气法进行二次处理，不仅保证了废水达标排放，还可回收金、银、铜等金属，实现了经济效益、社会效益和环境效益三者的统一。     

金矿非氰化浸金研究进展

随着易处理金矿石资源枯竭,含砷、含碳、高硫、超细颗粒金矿石已成为金矿开采的重点,这些难处理金矿通过常规氰化浸金等方法浸出效果差,由于氰化物有剧毒,会危害人体健康,并严重污染生态环境。非氰化法浸金因具有环保、浸出速率快、效率高等优点受到了广泛关注。在综述了硫代硫酸盐法、甘氨酸法、卤素法、石硫合剂法、碘化焙烧工艺、硫脲浸出法和非水溶液浸金7种非氰浸金方法的浸金原理及其在难处理金矿方面的最新研究进展的基础上,讨论了非氰浸金方法存在的浸出剂昂贵、浸出液中金回收困难、浸出体系复杂、浸出剂性质不稳定及消耗量大等问题,并对非氰浸金技术的发展方向进行了展望。      

Hydrometallurgy of precious metals recovery

The hydrometallurgical process for the treatment of gold and silver ores remained unchanged for the first 70 years of this century, and consisted essentially of leaching in cyanide solution followed by solid-liquid separation, with the solid residues being washed as efficiently as possible, and the leach liquor being treated by zinc cementation to recover the precious metals. White this process is generally extremely efficient and fairly cheap, it does have limitations in the treatment of low-grade ores and certain complex ore types. For example, ores with a high content of clay or other soft, fine minerals are usually difficult to filter, and losses of soluble gold or silver in the residues can be unacceptably high. In other situations, where the precious metal host rock contains high concentrations of sulphides such as pyrite or arsenopyrite, for example, or base-metal oxides or carbonates, the traditional process often suffers from poor gold recovery (due to encapsulation of the precious metals in the sulphides) or high cyanide consumption, or both of these. Whereas these occurrences were fairly rare (or were avoided!) in the first half of this century, they are now assuming great importance, and each year a higher percentage of world gold production derives from sources such as these.A number of new hydrometallurgical processes have been developed and implemented in the gold industry in the last 20 years, and these have transformed gold processing into a chemical “high tech” industry, and have allowed increasingly complex ore types and progressively lower grades of ore to be treated economically. As a result, in a period when gold production might have been expected to decline, world-wide production has almost doubled over the two decades.This paper describes the traditional cyanidation and zinc cementation processes, but focuses on the new developments in the industry. In particular, new leaching technologies such as heap leaching for low-grade ores and pressure leaching for refractory sulphide ores are discussed, as well as the carbon-in-pulp and carbon-in-leach processes that have effectively replaced filtration and countercurrent decantation on almost every gold plant built since 1980. Some emerging technologies such as bacterial leaching and resin-in-pulp are also discussed briefly.     

A Review on Recovery of Copper and Cyanide From Waste Cyanide Solutions

The mainstream technology for leaching gold from gold ore is still leaching in aqueous alkaline cyanide solution. However, when copper minerals are present in the gold ore, high levels of free cyanide must be maintained during leaching because many common copper minerals react with cyanide, forming copper cyanide complexes that deplete the solution of free cyanide. This results in a significant economical penalty through excessive cyanide consumption and loss of valuable copper in tails. Environmental constraints controlling the discharge of cyanide from mining industry are being tightened by local governments worldwide. The solution chemistry of copper in cyanide solution and various technologies for the recovery of copper and cyanide from barren gold cyanide solutions were reviewed in the paper. Direct recovery methods are mainly based on the acidification–volatilization–reneutralization (AVR) process or its modifications. These processes are not very efficient for treating low cyanide solutions and high metal cyanide solutions due to their substantial operational cost. Indirect recovery technologies by activated carbon, ion-exchange resins (IX) and solvent extraction (SX) have been extensively studied. The basic principle of these technologies is to pre-concentrate copper (and part of cyanide) into a small volume of eluant or stripping solution. The copper and cyanide in the resulted solutions can be further recovered by AVR or similar processes or by the electrowinning process. Activated carbon is only suitable for use as a polishing process to remove cyanide to lower levels from those cyanide solutions where the cyanide content is already low. Compared to activated carbon, ion exchange resins are less easily poisoned by organic matter and can usually be eluted at room temperature, and selectivity for particular metals can be achieved by the choice of the functional group incorporated into the bead or by the selective elution process. Solvent extraction process developed base on guanidine and modified quaternary amines exhibit relative fast extraction kinetics and can be operated in a continuous manner. It will be necessary to thicken and wash the solids in order to produce a clarified feed solution while treating the slurry from operations using carbon-in-pulp (CIP) for the recovery of gold. Other copper and cyanide recovery technologies such as biosorption or direct electrowinning were also proposed, but they have still not found their way to practical application.     

某环保药剂的浸金性能及贵液中金的活性炭吸附特性

为了促进我国自主研发的环保提金药剂完全替代剧毒NaCN用于黄金冶炼,解决氰化法提金过程中含氰废水、废渣污染环境的问题,研究了某环保药剂对不同金矿类型的适应性以及活性炭对环保药剂贵液中金吸附的选择性。研究结果表明,环保药剂对焙砂酸浸渣、高硫金矿中金的浸出效果与氰化法相当,对硫化金矿的浸出速度比氰化法快,浸出过程环保药剂用量与矿物类型有关。活性炭对环保药剂浸出贵液中金和银的吸附具有选择性,贵液pH值保持在10.0~10.5时吸附效果更好。由于环保药剂成分分析方法不健全,无法揭示浸出过程环保药剂的消耗量与矿物类型的关系,且无法检测吸附前后药剂的浓度及其成分变化。因此,在研究药剂分析方法的基础上,揭示环保药剂溶金机理和环保药剂体系与矿物的相互作用是当前研究的主要任务。     

金矿氰化提金工艺优化试验研究

针对金矿石中,金与硫化矿物伴生的特点,将金矿矿石充分细磨后,采用强化措施进行全泥氰化浸出。然而,硫化矿物在一定程度上溶于氰化物溶液,产生的可溶性硫化物将阻碍金的氰化浸出。为减少硫化矿物对金氰化浸出的影响,采用鼓空气的方法对矿浆进行预处理。同时,在氰化浸出过程中,通过对磨矿细度、溶解氧、硝酸铅以及氰化钠质量分数的控制,优化了金浸出效果。最终,在减少氰化物消耗量的前提下,金浸出率提高到95．4％。     

BOTA型氰化物浓度在线分析仪的升级及工业应用

氰化物浓度是氰化浸金工艺的重要参数,通过氰化物浓度在线检测控制可以有效减少氰化物消耗。介绍了BOTA型氰化物浓度在线分析仪的技术升级,由光度滴定替代电位滴定,提高了仪器测量性能及可靠性。升级后的BOTA-Ⅱ型氰化物浓度在线分析仪在排山楼金矿进行了工业应用,在氰化钠和某低氰药剂的浸出流程中均能实现氰化物浓度的在线测量,测量精度及可靠性满足要求,为企业带来了显著的经济效益。     

西藏高寒地区低品位金矿石堆浸提金试验研究

介绍了在西藏高寒地区采用堆浸工艺从低品位金矿石中提取金的试验结果,原矿石金品位为5．26g/t,属氧化矿石,经29d氰化浸出后,金的浸出率达到75．15％,相应的氰化钠耗量为0．223kg/t。     

氨氰法从含铜金矿石中提金研究与工业实践

本文对氨氰法浸取含铜金矿石进行了工艺过程研究，详细地考查了各操作条件对金浸取率的影响，对于含４．６７ＴＣｕ及５８ｇ／ｔＡｕ的金精矿，氨氰法的ＮａＣＮ用量约为氰化法的１／３，并且金浸出率也高，可达９３．５％，将实验结果用于工业生产（２８ｔ／ｄ）运转稳定正常，技术指标与小试结果相符合。