Catalytic effect of activated carbon on bioleaching of low-grade primary copper sulfide ores

The catalytic effect of activated carbon on the bioleaching of low-grade primary copper sulfide ores using mixture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans was investigated. The results show that the addition of activated carbon can greatly accelerate the rate and efficiency of copper dissolution from low-grade primary copper sulfide ores. The solution with the concentration of 3.0 g/L activated carbon is most beneficial to the dissolution of copper. The resting time of the mixture of activated carbon and ores has an impact on the bioleaching of low-grade primary copper sulfide ores. The 2 d resting time is most favorable to the dissolution of copper. The enhanced dissolution rate and efficiency of copper can be attributed to the galvanic interaction between activated carbon and chalcopyrite. The addition of activated carbon obviously depresses the dissolution of iron and the bacterial oxidation of ferrous ions in solution. The lower redox potentials are more favorable to the copper dissolution than the higher potentials for low-grade primary copper sulfide ores in the presence of activated carbon.     

Role of ore mineralogy in optimizing conditions for bioleaching low-grade complex sulphide ores

The role that ore mineralogy plays in understanding and optimizing the conditions favouring the bioleaching of complex sulphide ore containing high amounts of siderite was studied using mixed cultures of mesophilic bacteria, with emphasis on zinc, lead and copper recoveries. The influencing parameters investigated include particle size, stirring speed, volume of inoculum, pulp density, and pH. The results show that the mixed mesophilic cultures can extract about two and a half times the amount of zinc than copper over an equivalent period of time. The highest zinc and copper recoveries of 89.2% and 36.4% respectively are obtained at particle size of 75 lam, stirring speed of 150 r/min, pulp density of 10% （w/v）, 12% （v/v） inoculum concentration, and a pH of 1.6. Variations in elemental composition within different particle sizes resulting from the mineralogy of the ore account for the bioleaehing behaviour at varying particle sizes. The dissolution at varying pulp density, volume ofinoculum, solution pH and the low solution potential observed are also influenced by ore mineralogy.     

低品位硫化铜矿细菌浸出

采用正交实验方法,考察了矿石粒度、矿浆含量、接种量对大冶露天矿石和井下矿石的摇瓶浸出过程的影响.结果表明:粒度对露天矿和井下矿的酸耗影响大,对井下矿的浸出率影响高度显著; 矿浆含量对酸耗影响大,对浸出率则不显著; 在接种的初期,接种量对酸耗与浸出率都有影响,2d后接种量的影响消失; 井下矿浸出的最优工艺条件为:粒度<0.154mm,矿浆含量10%,接种量10%; 露天矿浸出的最优工艺条件为:粒度<0.154mm,矿浆含量20%,接种量7.5%.     

Simulated small-scale pilot heap leaching of low-grade copper sulfide ore with selective extraction of copper

The bioleaching of low-grade copper sulfide ore and the selective extraction of copper were investigated. Lix984 dissolved in kerosene was used as extractant. The results show that it is possible to selectively leach copper from the ores by heap leaching. The copper concentration of leaching liquor after 250 d is 2.17 g/L, and the copper concentration is 0.27 g/L after solvent extraction. The leach liquor was subjected to solvent extraction, scrubbing and selective stripping for the enrichment of copper and the removal of impurities. The pregnant copper sulfate solution produced from the stripping cycle is suitable for copper electro-winning.     

生物因素对次生硫化铜矿堆浸过程动力学的影响

假定生物浸出过程细菌的作用是间接作用,以实验室柱浸模拟次生硫化铜矿生物堆浸,基于细菌生长Monod方程及收缩核模型建立细菌生长动力学因子影响硫化矿浸出速率的动力学模型,研究铜浸出速率、溶液总铁、溶液中细菌浓度与时间的关系、细菌产出率和细菌饱和系数对浸出速率影响的动力学规律。动力学研究表明,在浸出早期,氧化浸出速率、溶液中总铁浓度以及溶液中的细菌数量增长较快,而在浸出后期则增长较慢。计算与实际结果表明,细菌最大生长比速率、细菌产出率、细菌饱和常数及溶液中Fe离子的浓度均对硫化矿的氧化浸出速率有明显影响,尤其在浸出早期影响较大。应用动力学模型仿真结果与实际基本符合,可分析生物因素对浸出的影响趋势。     

Effect of technological factors on bacterial leaching of low-grade Ni-Cu sulfide ore

1　ＩＮＴＲＯＤＵＣＴＩＯＮＢａｃｔｅｒｉａｌｌｅａｃｈｉｎｇｗｉｔｈａｕｔｏｔｒｏｐｈｉｃｂａｃｔｅｒｉａ ,ｓｕｃｈａｓＴｈｉｏｂａｃｉｌｌｕｓｆｅｒｒｏｏｘｉｄａｎｓ (Ｔ .ｆ.) ,ｈａｓｂｅｅｎｅｘｔｅｎｄｅｄｔｏｓｏｍｅｐｏｌｙｍｅｔａｌｌｉｃｓｕｌｆｉｄｅｏｒｅｓ[1] .ＡｆｅｗｏｆｐａｐｅｒｓｏｎｂｉｏｌｅａｃｈｉｎｇｏｆＮｉ Ｃｕｓｕｌｆｉｄｅｏｒｅｗｅｒｅｐｕｂｌｉｓｈｅｄ .Ｔｏｒｍａ[2 ] ｒｅｐｏｒｔｅｄｔｈａｔｔｈｅｌｅａｃｈｅｄＮｉ,ＣｕａｎｄＣｏｗｅｒｅａｌｌｏｖｅｒ 6 0 %ｉｎ 10ｄ…     

低品位氧化铜矿氨-硫酸铵体系过硫酸铵氧化浸出

以过硫酸铵为氧化剂,研究低品位氧化铜矿在氨-硫酸铵体系氧化浸出工艺。讨论氨/铵离子摩尔比、总氨浓度,氨、硫酸铵和过硫酸铵的浓度,反应温度,液固比,反应时间和搅拌速度等操作条件对铜浸出的影响。结果表明:在92.8%的矿样粒径小于0.045 mm,氨、硫酸铵和过硫酸铵浓度分别为2.4、1.8和0.100 mol/L,浸出时间为90 min,温度为30℃,液固比(mL/g)为5:1,搅拌速度为500 r/min时的优化条件下,低品位铜矿的铜浸出率达87.7%。     

Co-extraction of valuable metals and kinetics analysis in chlorination process of low-grade nickel-copper sulfide ore

To efficiently co-extract Ni and Cu from low-grade nickel-copper sulfide ore, chlorination roasting with NH₄Cl followed by a water leaching process was investigated. The results show that 98.4% Ni and 98.5% Cu can be synchronously extracted when the ore particle size is 75-80 μm, the roasting time is 2 h, the mass ratio of NH₄Cl to ore is 1.6:1 and the roasting temperature is 550 °C. The evolution behavior of various minerals was elucidated using X-ray diffraction (XRD) coupled with scanning electron microscopy (SEM). The kinetics of the chlorination process based on the differential thermal and thermogravimetric analysis (DTA-TG) data was analyzed by Kissinger method and Flynn-Wall-Ozawa (FWO) method. The chlorination process of low-grade nickel-copper sulfide ore mainly contains two stages: the decomposition of NH₄Cl and the chlorination of ore. The maximum apparent activation energies (E_a) at two stages are determined to be 114.8 and 144.6 kJ/mol, respectively. The condensed product of exhaust gas is determined to be ammonium chloride, which can be recycled as the reactant again, making the process economic and clean.     

Transformation and leaching kinetics of silicon from low-grade nickel laterite ore by pre-roasting and alkaline leaching process

The mineralogical phase transformation of a low-grade nickel laterite ore during pre-roasting process and the extraction of silicon during alkaline leaching process were investigated. The results indicate that the reaction activity of nickel ores is effectively improved by pre-roasting at 650 °C for 2 h, because of the transformation of lizardite into magnesium olivine and protoenstatite. When finely ground ore samples (44–61 μm) pre-roasted firstly react with sodium hydroxide solution (60 g/L) with a solid/liquid ratio of 1:5 at 140 °C for 120 min, the extraction of silicon can reach 89.89%, and the other valuable elements of magnesium, iron and nickel are accumulated in the solid residues. The leaching kinetics of nickel laterite ore can be described successfully by the diffusion through the product layer control model. The activation energy is calculated to be 11.63 kJ/mol and the kinetics equation can be expressed as 1–3(1–x)^2/3+2(1–x)=13.53×10^?2exp[–11.63/(RT)]t.     

低品位硫化铜矿的细菌浸出

以宁夏某低品位硫化铜矿为研究对象,利用嗜酸氧化亚铁硫杆菌(Acidithiobacillusferrooxidans)和嗜酸氧化硫硫杆菌(Acidithiobacillusthiooxidans)的混合菌,采用摇瓶浸出、小型柱浸和大型柱浸对矿石可浸性进行研究;采用X射线衍射仪分析矿物及其浸渣的成分;采用扫描电镜分析浸渣表面形貌及其表面元素的含量.结果表明摇瓶矿浆浓度为5%,浸出55d铜浸出率为94.38%;小型柱浸处理矿石2.10kg,矿石粒度小于15mm,浸出226d铜浸出率为62.50%;大型柱浸处理矿石77.85kg,矿石粒度小于25mm,浸出285d铜浸出率为50.63%.柱浸过程中,铜的浸出速率逐渐下降;浸渣中钙含量基本不变,而元素硫的含量明显增加,且存在新的石膏相;浸出后矿石表面元素硫、钙、铁的含量明显增加,在浸出过程中生成的硫酸钙结晶覆盖在矿石表面,铁在矿石表面形成沉淀,使矿石的渗透性变差,导致铜的浸出率逐渐下降.     

Dominance of Acidithiobacillus at ore surface of Zijinshan commercial low-grade copper bioleaching heap

The microbial community structure in the ore surface of Zijinshan commercial low-grade copper bioleaching heap was investigated by 16S rRNA gene clone library.For both bacteria and Archaea,105 clones were sequenced.The dominant bacteria species present in the ore surface were Acidithiobacillus and Leptospirillum,accounting for 51.42% and 48.57%,respectively. However,for the Archaea,only one operational taxonomic unit(OUT)belonged to Ferroplasma acidiphilum.These results indicate that function of genus Ac...     

膜生物反应器浸出镍钼矿

采用对钼有一定耐受性的嗜热金属硫叶菌结合膜反应器浸出镍钼矿。结果表明：由于膜生物反应器（MBR）中膜的过滤作用,使浸出液中的钼浓度保持在该菌可以耐受的范围内,从而实现细菌对矿物相对高效的浸出。在矿浆浓度100mg/L、通气量1.0L/min下,将MBR浸出液中钼被控制在不同浓度,镍、钼的浸出率各不相同。当MBR浸出液中钼的浓度不超过395mg/L时,镍和钼的浸出率达到79.57%和56.23%;而在相同条件下的柱浸,镍、钼浸出率为75.59%和54.33%,低于相同条件下MBR浸出。     

氨-硫酸铵体系过硫酸盐氧化含钙镁碳酸盐低品位铜矿的浸出动力学(英文)

研究在氨?硫酸铵体系中用过硫酸盐氧化低品位铜矿浸出动力学,确定搅拌速度、浸出温度、矿物粒度及氨、硫酸铵和过硫酸钠的浓度对浸出的影响。结果表明,搅拌速度在300r/min以上时对浸出速度无影响,浸出速度随反应温度及氨、硫酸铵和过硫酸钠浓度的增大而增加。对浸出渣的EDS和物相定量分析表明斑铜矿被过硫酸盐氧化而溶解于氨?硫酸铵溶液。用产物层的界面传质和扩散控制的收缩核模型分析铜矿的溶解动力学,其表观活化能为22.91kJ/mol,同时获得了描述浸出过程的半经验动力学方程,其对氨、硫酸铵和过硫酸钠的浓度的表观反应级数分别为0.5、1.2和0.5。     

Dominance of Acidithiobacillus at ore surface of Zijinshan commercial low-grade copper bioleaching heap

The microbial community structure in the ore surface of Zijinshan commercial low-grade copper bioleaching heap was investigated by 16S rRNA gene clone library. For both bacteria and Archaea, 105 clones were sequenced. The dominant bacteria species present in the ore surface were Acidithiobacillus and Leptospirillum, accounting for 51,42% and 48.57%, respectively. However, for the Archaea, only one operational taxonomic unit （OUT） belonged to Ferroplasma acidiphilum. These results indicate that function of genus Acidithiobacillus in the commercial low-grade copper bioleaching heap may be underestimated. More detailed and quantitative information on microbial community structure over time are now under investigation.     

低品位铝土矿选矿技术的优化

以铝硅比4左右的低品位铝土矿为原料,YG作捕收剂,碳酸钠作调整剂,通过实验探讨了正浮选方法提高一水硬铝石铝硅比的影响因素和工艺条件.对不同选矿流程的技术经济指标做了简要的对比.     

Bio-leaching of low-grade large porphyry chalcopyrite-containing ore

1　ＩＮＴＲＯＤＵＣＴＩＯＮＤｅｘｉｎｇＣｏｐｐｅｒＭｉｎｅｉｎＪｉａｎｇｘｉＰｒｏｖｉｎｃｅ ,Ｃｈｉ ｎａ ,ｉｓａｌａｒｇｅｃｏｐｐｅｒｄｅｐｏｓｉｔａｔｗｈｉｃｈａｒｏｕｎｄ 50 0ｍｉｌ ｌｉｏｎｔｏｎｓｏｆｗａｓｔｅｒｏｃｋｓｃｏｎｔａｉｎｉｎｇ 0 .1%～ 0 .3%ｃｏｐｐｅｒａｒｅｐｒｏｄｕｃｅｄ ,ａｎｄａｐｐｒｏｘｉｍａｔｅｌｙ 1.2ｍｉｌｌｉｏｎｔｏｎｓｏｆｍｅｔａｌｃｏｐｐｅｒｃｏｎｔａｉｎｅｄｉｎｔｈｅｓｅｌｏｗ ｇｒａｄｅｏｒｅｓｃｏｕｌｄｎｏｔｂｅｅｃｏｎｏｍｉｃａｌｌｙｒｅｃｏｖｅｒｅ…     

Electrochemical studies on interplay of mineralogical variation and particle size on bioleaching low grade complex sulphide ores

The interplay of mineralogical variation and mineral phase distribution within varying particle sizes on the dissolution behaviour of a low grade complex sulphide ore was investigated through bioleaching experiments and electrochemical technique. Investigations were carried out utilizing mineralogical data on the variations in mineral and phase distribution within particle sizes of <53 μm, 53–75 μm, 75–106 μm and 106–150 μm in mixed mesophilic cultures of Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans. Electrochemical behaviour was studied using particulate electrodes from the four varying particle sizes and from massive electrodes prepared from the two major sulphide mineral rich phases (sphalerite-rich and galena-rich) and a complex mineralogical phase of the bulk ore. Bioleaching studies reveal the highest recoveries at a particle size of 75 μm, while electrochemical investigations reveal the highest dissolution at particle size of 106 μm. Electrochemical results show that sphalerite rich phase has the highest dissolution rate while galena-rich complex phase has the least. SEM studies confirm the highest bacterial attack at the sphalerite-rich phase. The discrepancies between the dissolutions within particle sizes obtained from bioleaching experiments and electrochemical studies are consistent with and attributed both to the physical and mineralogical influences. Electrochemical behaviour is influenced and controlled by galvanic interaction resulting from mineralogical variation, while bioleaching behaviour is influenced by mineralogical variation as well as physical effect of particle size.     

黄铁矿、单质硫、亚铁离子对浸矿微生物产生胞外多聚物的影响(英文)

嗜酸浸矿微生物产生的胞外多聚物(EPS)在酸性矿坑水的产生和硫化矿的浸出过程中,有着非常重要的影响,胞外多聚物(EPS)介导细胞与能源物质的接触,对有机薄膜的形成和细菌与基础物之间的相互作用起着重要的作用。对7株浸矿菌在不同能源培养物下产生的EPS的量以及EPS的化学成分进行研究,发现EPS含有化学成分糖、蛋白质、糖醛酸等,细菌的种类和能源物质对EPS的量和成分有很大影响。结果表明,以黄铜矿为能源物质的细菌产生的EPS要比以单质硫和亚铁为能源物质产生的EPS量多,EPS含量最高为(159.43±3.93)mg/g,是由Leptospirillum ferriphilum CBCBSUCSU208015在黄铁矿为能源物质下产生的。     

Bioleaching of low-grade copper sulphides

The bioleaching behavior of low-grade copper sulphides under the condition of preferential solution flow was investigated through experiments. ,The experiment of bioleaching was conducted within the multifunction autocontrol bioleaching apparatus. The results show that the concentrations of Cu^2＋ and total Fe increase slowly at the beginning. The recovery rate decreases with the increase of depth of dump. The preferential solution happens within the fine region when the application rate is low, and the recovery rate of the fine region is higher than that of the coarse region. The content of fine ore particles within both fine and coarse regions increases during the leaching period, and the preferential solution flow shifts from fine region to coarse region. The surface of the ores at the top of dump is attacked seriously, and the ores in the middle is attacked slightly. There are plenty of crackles on the surface of bottom ores because of the precipitation layer on the surface.     

某硫化镍铜矿磨矿沉砂中贵金属工艺矿物学研究

基于矿物自动分析(MLA)技术,结合多种手段,对某硫化镍铜矿磨矿沉砂的进行了工艺矿物学研究。结果表明,沉砂主要由30%金属矿物和70%硅酸盐脉石矿物组成,其中目的元素镍、铜、钴、金、银、铂、钯含量分别为0.82%、1.10%、0.04%、0.75 g/t、10.50 g/t、0.23 g/t、0.13 g/t。独立的金矿物主要为合金相,独立的铂钯矿物包括合金相、砷化物和铋碲化物。金及铂钯矿物虽粒度细小,但部分已单体解离,且载体矿物大多为金属硫化物;银多以碲银矿形式赋存,碲银矿粒度细小,且银矿物大多呈包裹体分布于金属硫化物中。