高砷难处理金精矿细菌氧化-氰化提金

通过在高砷金精矿中配入不同比例的低砷碳酸盐型金精矿,使其所含硫、砷及铁等主要矿物成分含量发生变化,研究给矿中铁砷摩尔比对难处理高砷金精矿细菌氧化一氰化浸出效果的影响.结果表明:含砷金精矿中铁砷摩尔比直接影响细菌预氧化的效果,同时也影响细菌的活性和溶液中铁砷摩尔比的变化,给矿中铁砷摩尔比越高,溶液中的铁砷摩尔比也越高,且随着给矿中铁砷摩尔比的增加,溶液中铁砷摩尔比的变化幅度加大,给矿中铁砷摩尔比介于4.6~2之间,有利于细菌预氧化和氰化浸出,铁、砷氧化率分别由6.14%和7.38%提高到89.90%和93.60%,金、银浸出率分别由64.18%和35.93%提高到97.78%和88.83%,较好地改善细菌氧化效果,稳定和优化细菌预氧化过程.     

湖南某高砷难处理金精矿的细菌氧化-氰化提金实验研究

湖南某高砷金精矿属于难处理矿石,含砷11.28%,含金66.18g/t,金的直接浸出率仅为21.91%.通过该样品5%、10%、15%、20%矿浆浓度的细菌氧化试验,发现金精矿砷的氧化率达到93%以上.细菌氧化渣的金浸出率随着矿浆浓度的增大而降低,5%矿浆浓度下细菌氧化渣的金浸出率为93.15%;10%矿浆浓度下细菌氧化渣的金浸出率为92.46%;15%矿浆浓度下细菌氧化渣的金浸出率为90.50%;20%矿浆浓度下细菌氧化渣的金浸出率为87.58%,比未经处理时金的直接氰化浸出率21.91%有了很大的提高,预处理效果很好.     

含砷难处理金矿的细菌预氧化－氰化法提金研究

研究了我国二种难处理会砷金矿（半壁山、包古图）的细菌（Ｔ．ｆｅｒｒｏｏｘｉｄａｎｓ）预氧化槽浸工艺及其基础理论，讨论了初始接种量、矿浆浓度、铁离子浓度及矿物工艺学参数等因素对细菌氧化毒砂的影响，初步探讨了细菌浸出机理及反应动力学，并讨论了砷硫化物氧化率、金解离率及金氰化浸出率的关系。     

某难处理金精矿热压预氧化-氰化浸金实验

对某难处理金精矿进行了热压预氧化-氰化浸金实验,探讨热压预氧化温度、时间、氧化分压和矿浆浓度对金浸出率和氰化钠耗量的影响。结果表明,在粒度-44μm占90.74%、温度220℃、矿浆浓度25%、氧分压0.8 MPa和转速750 r/min条件下预氧化2.5 h,砷主要以稳定的结晶状砷酸铁或者臭葱石形式被固定在氧化渣中;预氧化渣在矿浆浓度33%、pH=10~11、初始氰化钠浓度0.3%和活性炭浓度25 g/L条件下氰化浸出24 h,与金精矿直接氰化相比,浸出率由11.21%提高至95.75%,氰化钠耗量从46.99 kg/t降低至1.36 kg/t。     

采用中温菌和常温菌浸出含砷金精矿

考察了不同矿浆浓度和接种量对细菌浸出含砷金精矿的影响。结果表明：中度嗜热嗜酸铁氧化菌MLY和嗜酸氧化亚铁硫杆菌（Acidthiobacillus ferrooxidans,At.f）的浸矿效果不同。MLY和At.f对含砷金精矿的浸出机理也不同;接种MLY的矿浆中,可能主要是溶液中的细菌将Fe^2＋氧化为Fe^3＋,再由Fe^3＋氧化溶解矿物,即以间接浸出作用为主;而接种At.f可能首先是At.f被吸附到矿物表面,通过细菌与矿物之间的某种界面作用引起矿物溶解,矿物溶解产生的Fe^2＋被游离菌氧化成为Fe^3＋,从而溶解矿物,即At.f浸出可能包括直接作用和间接作用的共同效应。     

添加软锰矿强化复杂难选冶含砷金矿的生物氧化过程（英文）

通过控制生物浸出试验中软锰矿用量、过程p H和细菌接菌量等条件,对添加软锰矿强化复杂难选冶含砷金矿的生物氧化过程进行研究。结果表明,添加软锰矿可以缩短含砷金矿的生物氧化时间,砷的浸出率达到94.4%。反应过程中实现了含砷金矿中砷黄铁矿氧化的同时,软锰矿中锰元素高效浸出。生物浸出渣的氰化浸出实验结果表明,经软锰矿强化生物氧化后,生物浸出渣中金的氰化浸出率达到95.8%。生物浸出过程中,添加软锰矿能提高生物浸出溶液的氧化还原电位,从而促进生物氧化过程,且添加软锰矿后生物浸出过程中存在两种不同的反应方式。     

难处理高砷金矿的细菌氧化-提金研究

采用经过驯化的HQ0211菌对高砷金矿进行氧化预处理-氰化提金实验研究.该矿石含金128.5 g/t,含砷16.84%(质量分数,余同),含硫21.72%,含铁26.62%,氰化浸出率只有29.35%,是典型的高砷难处理矿.经过细菌氧化预处理,金矿脱砷率达到96.2%,失重率达到43.9%.矿石的金氰化浸出率由原来的29.35%提高到92.57%,效果十分显著.     

细菌氧化预处理含砷难处理金矿的研究进展

含砷难处理硫化矿经过细菌预氧化,将包裹Au的硫化矿物毒砂、黄铁矿等溶解、破坏,将Au暴露出来,可大大提高后续氰化浸出中Au的回收率。细菌氧化技术具有投入低、工艺简单、污染轻或无污染等优点。作者在回顾细菌浸矿发展历史与现状的基础上,着重阐述了含砷难处理金矿细菌氧化预处理的机理、氧化菌种和工艺流程,并提出了该技术现存的一些亟待解决的问题。     

低品位微细粒金矿浮选精矿的处理工艺研究

针对低品位微细粒金矿中金的赋存特点,对其浮选精矿进行高压氧化-氰化浸出工艺处理。重点考察了高压氧化预处理过程中的温度、液固比和氧化时间对预处理效果的影响。预处理渣再磨后氰化浸出,金的浸出率(对浮选精矿)为94.30%,渣率为10.88%。     

新疆哈图金矿含砷金精矿加压氧化预处理工艺研究

采用具有代表性的哈图含砷金精矿进行了硫酸介质加压氧化预处理工艺研究。通过正交试验,确定了适宜的预处理工艺条件．考查了氧化矿浆电位对预处理效果的影响。在此条件下取得了预处理后精矿氰化金浸率97．0％,较直接氰化提高了16．5个百分点的良好结果。     

A new extraction process of carbonaceous refractory gold concentrate

A new hydrometallurgical process for a carbonaceous refractory gold concentrate at ambient temperature and pressure was presented, including grinding-leaching, intensified alkaline leaching（IAL）, thiosulfate leaching and cementation by zinc powder. The experimental results show that the grinding-leaching and intensified alkaline leaching process result in the selective oxidation of arsenopyrite and pyrite. The oxidation ratio of As is 96.6%, and 46.7 % for S. The total consumption of NaOH in alkaline leaching is only 28 % of that theoretically calculated under the conditions of full oxidization for the same amount of arsenopyrite and pyrite transforming into arsenates and sulfates, and 83.6% of gold is synchro-dissoluted by thiosulfate self-generated during pretreatment. Since the carbonaceous matter in concentrate possesses a strong capability of preg robbing, the cyanidation process is not suitable for the extraction of gold after pretreatment. However, the gold leaching rate by thiosulfate leaching for 24 h is increased to 91.7% from 0 - 3.2% by ultra-fine grinding without the pretreatment. The recovery of gold by zinc cementation gets to 99.6%. Due to the thiosulfate self-generated during alkaline leaching, the reagent addition in thiosulfate leaching afterwards is lower than the normal one.     

Bioleaching of refractory gold ore （ Ⅲ ）——Fluid leaching Jinya refractory gold concentrate by Thiobacillus ferrooxidans

A novel fluidized-bed reactor was designed and installed for bloleaching in a semi-continuous way, by which a process for biuleaching-cyanidation of Jinya refractory gold arsenical concentrate was studied. The arsenic extraction rate reaches 82.5 % after 4-day batch biooxidation of the concentrate under the optimized condition of pH 2.0, ferric ion concentration 6.Sg/L and pulp concentration 10%. And leached rate of gold in the following cyanida.tion is over 90%. The parameters of three series fluidized-bed reactors exhibit stability during the semi-continuous bioleaching of the concentrate.Armmic in the concentrate can be got rid of 91% after 6-day leaching. Even after 4 days, 82% of arsenic extraction rate was still obtained. The recovery rates of gold are 92 % and 87.5 % respectively in cyaniding the above bioleached residues.The results will provide a base for further commercial production of gold development.     

Differences of cyanide leaching between calcine and dust from refractory gold concentrates

Differences of cyanide leaching between the calcine and the dust from a refractory gold concentrate were investigated by comparative method. Results showed that gold leaching efficiencies of the calcine and the dust were 85.31% and 54.30%, respectively, with direct cyanidation. Contents and existing forms of arsenic and carbon were the main reasons for those differences. The maximum gold leaching efficiencies of the calcine and the dust were 87.70% and 58.60%, respectively, with cyanidation after NaOH pre-leaching. Harmful elements removal, gold loss in NaOH pre-leaching and iron oxides hindrance codetermined gold leaching efficiencies of the calcine and the dust. After H₂SO₄ pre-leaching, the maximum gold leaching efficiencies of the calcine and the dust achieved 94.96% and 80.40%, respectively. The effect of carbonaceous matter was the main reason for differences for leaching efficiencies of the calcine and the dust. Based on those differences, two proper gold extraction processes were put forward, and gold leaching efficiencies for the calcine and the dust achieved 94.91% and 91.90%, respectively.     

重金属强化含金矿石的氰化浸出

通过分析铊、铋、汞和铅等重金属强化金氰化溶解的电化学原理,对含金氧化物矿石和难浸硫化物金精矿进行了重金属强化浸金研究.结果表明:重金属对金氰化溶解的阳极过程有显著的强化作用,但在常规供氧条件下,金的溶解速率并未显著提高;只有同时采用阴极强化措施,才能使重金属起到显著提高金溶解速率的作用;对于含金氧化物矿石,单独采用重金属强化即可明显提高浸金速率,如果在过氧化氢助浸的基础上添加重金属,金的浸出速率会有更大幅度的提高;对硫化物金精矿而言,单独采用重金属无明显强化效果,只有在添加过氧化氢作为辅助氧化剂的基础上,重金属对金的浸出才能起到强化的作用,该体系中过氧化氢起到了强化阴极过程和氧化硫化物的双重作用.     

Chemical behaviors of different arsenic-bearing sulphides bio-oxidated by thermophilic bacteria

1INTRODUCTION Arsenic bearinggoldoreiswidelydistributedinprovincesofYunnan,Guizhou,Sichuan,Guan gxi,Guangdong,Hunan,Jiangxi,Liaoning,Jilin,Hebei,Shanxi,Gansu,Qinghai,Xinjiang,etc.Withtheprocessdevelopmentofbacteriummetal lurgy[1,2],suchgoldoreresourcemaybereasona blyutilized,however,arsenicintheseoresishigh lytoxictotheleachingbacteriaandbecomesthe researchfocus.Arsenicisacomplexandvitalele mentofarsenic bearingmineralswiththeelectronconfigurationof4s34p3[3].WhenAslosesthree electro…     

国内氰化法浸出金矿中金的研究进展

基于中国期刊全文数据库(CNKI),检索了2014~2018年氰化法浸出金矿中金的论文和专利,对国内相关研究进行综述讨论。文献分析表明,对贫金矿的开发是近年来研究的热点,有关氰化工艺、氰化条件、尾渣处理和贫液净化的研究较多,但氰化浸出条件之间的交互影响,以及脉石矿物对氰化浸出效率影响的相关研究较少。建议通过工艺完善、加强应用软件模拟等研究,不断完善金矿氰化浸出理论与实践,提高金矿资源的利用率。     

硫精矿中难选金银焙烧浸出研究

某高金硫精矿全泥氰化时金和银的浸出率低,一段焙烧预处理会造成金和银的二次包裹。实验结果显示,二段焙烧效果优于一段焙烧效果,能降低氧化铁的烧结程度,减少铁氧化物对金、银的包裹,金、银浸出率分别为79.86%、68.13%。添加剂实验结果表明,焙烧过程加入NaOH,银浸出率大幅提高;加入CaO有利于金的浸出;加入KMnO4能降低焙砂硫品位。以NaOH、CaO、KMnO4为组合焙烧添加剂,金、银浸出率提高至87.43%、85.86%。扫描电镜观察到,加入组合焙烧添加剂有利于焙砂孔隙度的提高,氰化尾渣表面腐蚀较为严重,有利于浸出剂与金、银的接触。 关健词:含金硫精矿;全泥氰化;二段焙烧;焙烧添加剂     

Use of ferricyanide for gold and silver cyanidation

Low gold and silver leaching kinetics has been commonly observed in traditional gold-silver cyanidation process, especially in heap leaching and in situ leaching operations. The different mineralogy of gold and silver in the ores is suspected to be the main reason, e.g., the occurrence of low solubility acanthite (Ag2S) typically results in low overall silver extraction. Due to the low solubility of oxygen in cyanide solution, the reactivity and availability of oxidant is believed to be the critical limitation for gold and silver dissolution. The use of ferricyanide as the auxiliary oxidant for gold and silver cyanidation has been examined. The rotating disc test results prove the assistant effect of ferricyanide on increasing the dissolution rate of gold and silver. The potential use of ferricyanide in gold/silver cyanidation process is proposed based on the leaching results of actual ores.