采用磁场强化浸出提高某含铜难浸金矿浸出率的试验研究

某含铜难浸金精矿常规硫脲浸出率仅48.71%,采用细菌预处理及磁场强化浸出后金浸出率可达92.86%。在常规硫脲浸出、低氧细菌预处理及氧化渣浸金试验中添加磁场可明显促进金的浸出,提高浸出率。     

提高含铜难浸金矿金浸出率的细菌预处理研究

江西某含铜难浸金矿的金精矿常规金浸出率仅48.71%,采用富氧细菌氧化预处理后金浸出率可达91.67%。鉴于富氧、低温控制工艺的高要求不宜实际推广,研究中开展了低氧细菌预处理试验,并引入磁场强化预处理,达到金浸出率91.72%的较理想指标。同时,对磁场强化细菌预处理过程的机理进行了分析探讨。     

酸性硫脲浸出废旧手机线路板中金的研究

采用硝酸氧化预处理-酸性硫脲浸金法浸出废旧手机线路板中金, 考察了物料粒度、氧化剂Fe₂(SO₄)₃质量分数、pH值、硫脲浓度、温度等因素对酸性硫脲浸金过程的影响, 结果表明: 物料粒度越小, 金浸出率越高; 当氧化剂Fe₂(SO₄)₃用量0.3%、pH值1.5、硫脲浓度12 g/L、温度30 ℃, 磁力搅拌反应2 h, 金浸出率为88.54%。硝酸氧化预处理-酸性硫脲浸金工艺能高效、无毒地浸出手机线路板中的金, 为“城市矿山”开采提供技术支撑。     

难浸金精矿硫脲浸金试验研究

讨论了某难浸金精矿的相关性质,分析了硫脲浸出剂的浸金机理,明确了硫脲浸金工艺流程。通过试验,分析了焙烧工艺、磨矿细度、硫脲用量、矿浆pH值、矿浆温度和浸出时间等影响因素,确定了硫脲浸金最佳工艺参数。在最佳工艺参数条件下,获得了金浸出率超过93%、银浸出率超过94%的工艺指标。     

镇源浮选金精矿细菌氧化——硫脲浸金的试验研究

对镇源难处理浮选金精矿作了细菌氧化－硫脲浸金的试验研究，细菌氧化在模拟堆浸的不充气搅拌和矿浆液固比为１：１的操作条件下进行，使用菌株Ｉ，氧化４２天，金的浸出率达８３．５１％；使用菌株Ⅱ，氧化１４天，金的浸出率达８５．１６％；而对金精矿直接进行硫脲浸出，金的浸出率不大于７％。此项技术为开发利用镇源特大型金矿提供了一条路子。     

铜-金矿石的硫脲浸出

加拿大用硫脲从含０．４％Ｃｕ和５．６ｇ／ＬＡｕ的矿石中浸出Ａｕ。研究的参数是酸预处理、浸出时间、ｐＨ、硫脲浓度和采用的氧化剂。金提取率为８９％,硫脲消耗为３．９ｋｇ／ｔ。在ｐＨ为３时浸出不耗酸。推荐酸洗预处理以改进金的浸出并减少硫脲消耗。用硫酸铁作氧化剂获得了最好的金回收率,虽然较为昂贵。硫脲溶铜比氰化物少３倍。最佳浸出条件为：酸洗预处理,硫脲平均加入量为１２ｇ／Ｌ,浸出时间７２ｈ,ｐＨ为３。氧化还原电位波动在４１０～４５０ｍＶ／ＳＨＥ之间。铜-金矿石的硫脲浸出@许孙曲     

吉林某难处理含铜金精矿硫脲浸金试验研究

针对吉林某难处理含铜金精矿进行了硫脲浸金试验研究,考察了硫脲用量、硫脲浓度、三价铁离子浓度和浸出时间等因素对浸金效果的影响。试验结果表明,在矿浆液固比为4∶1,矿浆pH值为1,硫脲用量160kg/t时,常温浸出8h,金的浸出率可由全泥氰化浸出的57.14%提升至91%以上。浸金过程中铜的浸出率保持在2.5%以下,铜浸出较少。      

难处理含砷金精矿的生物预氧化—硫脲浸金工艺研究

本文用氧化亚铁硫杆菌（Ｔｈｉｏｂａｃｉｌｕｓｆｅｒｒｏｏｘｉｄａｎｓ）对含砷金精矿进行了氧化预处理脱砷实验，脱砷率达９８％。生物浸渣用ＳＯ２－硫脲浸取体系浸出金，不仅降低了硫脲用量，而且缩短了浸出时间，金的浸出率达９５％以上。该工艺具有广阔的应用前景。     

某高硫砷难浸金精矿的细菌氧化预处理

为提取广西某高硫砷难浸金精矿中的金,利用氧化亚铁硫杆菌,通过鼓泡搅拌槽浸试验对该金精矿进行细菌氧化预处理,浸出铁和砷,分解黄铁矿和砷黄铁矿,使金得以暴露以便氰化浸出.研究了pH、细菌接种量、矿浆浓度、通气量以及矿石粒度等因素对细菌氧化预处理过程的影响,结果表明:细菌氧化预处理该高硫砷难浸金精矿的适宜条件为pH=2.0、接种量10%(体积分数)、矿浆质量浓度100 kg/m3、通气量0.1 L/(L·min),在此条件下,细菌作用10 d后,Fe和As的浸出率分别可达到50%和90%以上;矿石的粒度越小越有利于细菌预处理;细菌预处理过程中砷酸铁沉淀的生成对铁和砷的浸出均不利,有待采取措施.     

生物预氧化—酸性硫脲浸金联合工艺

详细介绍了生物预氧化技术的原理、硫脲浸金法的反应机理和研究进展,以及生物预氧化—酸性硫脲浸金联合工艺的研究现状及其应用前景。采用生物预氧化—酸性硫脲浸金联合工艺处理新疆某低品位难处理金矿,对影响硫脲浸金的因素进行了实验探索,得到了该体系下较优的硫脲浸出条件为:温度25℃、pH值1.5、液固比5∶1、硫脲浓度25kg/t、浸出时间5h、搅拌速度350r/min,金浸出率最高可达97.84%。     

磁处理提高广东某含铜金矿金浸出率的试验研究

广东某含铜浮选金精矿的金品位为8.312 g/t、铜含量为5.18%,工业上采用全泥氰化、浸出渣浮选回收铜的工艺流程。矿石中较高的铜含量不仅消耗大量的氰化物,还影响了金的浸出效果。为了进一步提高金的浸出率、降低氰化物用量,采用加温常压化学预氧化浸铜—浸铜渣氰化浸金工艺回收试样中的铜和金,并在磁处理条件下,考察了磁场强度、磁化时间、起始硫酸浓度、NaCl浓度、浸出温度和浸出时间等因素对金、铜浸出率的影响。试验确定磁处理的最佳条件为：磁场强度150 kA/m,磁化时间50 min,磨矿细度-200目占88%,预氧化温度93 ℃,起始硫酸浓度0.77 mol/L,NaCl浓度0.76 mol/L,预氧化时间27 h。在此条件下进行氧化预处理浸铜及铜渣氰化浸金试验,固定搅拌强度为760 r/min,液固比为3∶1,氧气流量为160 mL/min,氰化钠用量为7 kg/t,铜和金的浸出率分别为85.76%、98.86%。较未进行磁处理的最佳指标（铜浸出率71.28%,金浸出率86.26%）相比,铜浸出率提高了14.48个百分点,金浸出率提高了12.60个百分点;此外,预氧化温度降低了2 ℃,预氧化时间减少了1 h,氰化钠用量减少了3 kg/t。研究结果表明磁处理能有效提高含铜金矿的铜、金浸出率,减少有毒氰化物的用量。     

含砷金矿微生物预氧化过程强化方法研究进展

微生物预氧化技术具有成本低、设备简单、环境友好等优点,在难处理金矿资源的开发利用中得到了巨大发展和广泛认可。然而,由于原料来源复杂、浸矿菌种耐砷性差、浸矿过程容易生成钝化产物等问题,微生物预氧化在实际生产中依然受到一定程度的制约。目前如何强化含砷金矿微生物浸出已成为该领域的研究热点和难点。综述了目前国内外含砷金矿微生物预氧化强化方法的研究现状,其中详细阐述了应用氧化剂、金属离子、原电池效应、表面活性剂、腐殖酸和磁化水等强化方法的研究进展及作用机理。在此基础上,展望了该领域未来研究的主要发展方向,为含砷金矿微生物预氧化工艺的进一步开发及应用提供参考。      

李坝(杜沟)金矿原生矿细菌氧化提金试验研究

本文采用细菌氧化法对李坝（杜沟）金矿低品位原生矿石进行预处理，矿石金浸出率由41％提高到62．77％．为西秦岭微细浸染型难浸金矿生物堆浸开发提供了依据。     

Research status and prospect of gold leaching in alkaline thiourea solution

In this paper, fundamentals, development and the recent research progresses of gold leaching in alkaline thiourea solution, which is the most prospective substitute for dissolving gold in cyanide solution, are reviewed. The mechanism of gold dissolution is the theoretical foundations for gold leaching in thiourea solution. The suitable oxidant should be the substances with moderate redox potential. An efficient stabilizing reagent selected for alkaline thiourea must be satisfied with two conditions: i.e., easily forming hydrogen–sulfur bond and a stable orbicular structure with thiourea molecular in alkaline medium. A series of electrochemical behaviors, adaptability to leach different gold ores and the correlative fundamentals have been studied in detail, gold leaching rate has been improved to 82.68%, the selectivity of gold dissolution has been anatomied based on complex theory. At present, the dissolution process and mechanism are not very well understood, the leaching rate is still lower than that of cyanidation and further studies are needed. It should be believed that gold leaching rate would be improved on a large degree when the key questions are resolved. These fundamentals are of vitally importance that gold leaching in alkaline thiourea solution quickly, high-efficiently and nontoxically will be realized industrially and successfully, translation of this new method into productivity will be quickened, widely industrial application of alkaline thiourea will be propelled, and persistent and harmonized development of gold industry will be accelerated.     

Two-step oxidation of a refractory gold-bearing sulfidic concentrate and the effect of organic nutrients on its biooxidation

Methods for improving the treatment efficiency of a refractory gold-bearing sulfidic concentrate are proposed. These methods consist of the oxidation of the concentrate during a two-step process, which includes a high temperature ferric leaching step and a subsequent biooxidation step, and the use of organic nutrients during the biooxidation step. The concentrate contained 34.7% pyrite and 7.9% arsenopyrite. The biooxidation of the concentrate (for a one-step process) was conducted at 45 °C in two bioreactors that were connected in series under continuous conditions. The pyrite and arsenopyrite oxidation levels after 240 h were 60.2% and 92.0%, and the gold recovery level by carbon-in-pulp cyanidation was 65.7%. The two-step process included the leaching of the concentrate by a biologically generated Fe³⁺-containing solution and the subsequent biooxidation of the leach residue. In this case, the pyrite and arsenopyrite oxidation levels after 240 h of biooxidation were 65.7% and 94.1%, and the gold recovery level was 71.7%.The effect of an organic nutrient (yeast extract) on biooxidation during the two-step process was studied. The pyrite and arsenopyrite oxidation levels after 240 h of biooxidation under mixotrophic conditions were 73.5% and 95.1%, and the gold recovery level was 77.9%. The effect of the organic nutrient on the microbial population was determined. Sulfobacillus thermosulfidooxidans and Acidithiobacillus caldus were the predominant microorganisms studied under both autotrophic and mixotrophic conditions. Archaeon Acidiplasma sp. MBA-1 was a minor component of the microbial community under autotrophic conditions but was one of the predominant microorganisms studied under mixotrophic conditions. These results suggest that the organic nutrient changed the composition and increased the activity of the microbial population.Thus, a two-step process with organic nutrients added during biooxidation may be considered as an effective strategy for treating refractory pyrite–arsenopyrite concentrates.     

某硫铁矿烧渣的硫脲法浸金银研究

针对某硫铁矿烧渣进行了硫脲法搅拌浸金、银研究,考察了磨矿细度、硫脲浓度、pH值、液固比、搅拌时间、矿浆温度、浸出剂种类对金、银浸出率的影响。结果表明,适宜的搅拌浸出条件为: 磨矿细度-0.074 mm粒级占89%、硫脲浓度15 g/L、pH=2.5、液固比3、搅拌时间7.5 h、矿浆温度50 ℃,此条件下金、银浸出率分别达到84.8%、72.1%。