反浮选工艺是提高酒钢弱磁精矿品质的有效途径

介绍了酒钢镜铁山复杂难选弱磁性铁矿石经焙烧磁选工艺选别的精矿,进一步采用阳离子反浮选工艺实施精选降杂、提高铁品位的研究及工业试验结果.通过实施浮选提质降杂,使困扰酒钢多年的焙烧磁选精矿品位得到了大幅度提高,SiO2杂质含量大幅度降低,与同期生产弱磁选精矿相比,铁精矿品位提高了4.05个百分点,SiO2降低了4.65个百分点,提铁降硅效果及经济效益十分显著,年产生综合经济效益3 000多万元.该研究成果预计2007年底实施产业化.     

难浸金矿石加石灰焙烧预处理的经验数学模型

加石灰焙烧是难浸金矿的一种新型预处理工艺。本文考察了这种预处理工艺在处理湖南某难浸金矿时的各种主要影响因素，提出了固硫、固砷及金浸出率与各影响因素之间的经验数学模型。     

工业固废和难处理矿石氯化处理综述

工业固废和难处理矿物作为金属资源的附载体,正在日益受到全世界的关注,高效提取其中的金属资源,对于固废的减量化或某些金属的战略安全具有重要意义。本文主要以氰化尾渣、硫酸烧渣、红土镍矿、磁性废料、钛渣、钒渣等工业废物和难处理矿石为关注对象,从氯化技术处理的角度进行总结综述。对于某些含高价值金属(如Au、Ag等)的固废或难处理矿物而言,氯化技术有着更大的优势。     

耐火材料行业中统计的应用

统计作为一种处理数据的方法和技术,在耐火材料行业中得到了广泛的应用。它为耐火材料生产的良好运行及耐火材料的未来采取重要决策,为耐火材料的抽样检验验收的顺利进行,为耐火材料的科学研究得出最后的结论,做出了不可磨灭的贡献。     

新型整体浇注炉门的应用实践

采用复合无机材料制备的新型浇注料具有良好的热稳定性,整体浇注炉门替代传统砌筑炉门的应用实践表明,新型炉门比传统炉门的外表面温度降低45～50℃,炉头温度略有升高。同时,在提高焦炉产量、热工效率、安装维修和改善作业环境等方面具有明显优势。     

Microstructure and properties of (1 − x)La0.9Ca0.1CrO3/x ZrO2 (x = 0–30 wt-%) composites

The microstructure and properties of Ca doped lanthanum chromate [La_0.9Ca_0.1CrO₃ (LCCO)] and zirconia (ZrO₂) composites [abbreviated as (1???x)LCCO/xZrO₂, x?=?0–30?wt-%] prepared by solid state reaction method are investigated in this paper whose potential application in heat resistant ceramics are also discussed. The growth and fusion of the LCCO grains are hindered by the ZrO₂ grains, which make the matrix grains refined. In the stable system, it is discovered that the density of the composites decreases, the porosity increases and the decrease amplitude of the bend strength after thermal shock at 600°C reduces with the increasing ZrO₂ content, which results in diminishing the bend strength gradually and enhancing the thermal shock resistance. When x?=?10–15?wt-%, the samples show the best thermal shock resistance realising a maximum thermal cycle times of 8. The material with x?=?20?wt-% exhibits excellent slag resistance.     

某块状硫化物型铜铅锌多金属矿选别工艺优化研究

新疆某复杂难处理铜铅锌多金属矿矿物组成复杂,由于次生铜离子的活化和弥散分布的金银矿物对黄铁矿和闪锌矿的活化作用,造成黄铁矿和闪锌矿具有良好的可浮性,而铅矿物嵌布粒度细,浮游性较差,采用石灰抑制黄铁矿和采用亚硫酸钠抑制闪锌矿时都对铅矿物造成较明显的抑制作用.生产中采用"铜铅混合浮选-铜铅分离-锌浮选"的工艺流程,存在有价...     

Enhancement of leaching refractory gold concentrate with high arsenic and sulphur content by ultrasonic electro-oxidation technology

Abstract

The ultrasonic leaching behaviour of refractory gold concentrate has been investigated simultaneously at the anode in hydrochloric acid solution and at the cathode in sodium hydroxide solution. An electrochemical reactor divided into three compartments (anode, middle and cathode compartment) by anion and cation exchange membrane is employed for these experiments. Various parameters, which include solid–liquid ratio, current density, leaching temperature, particle size, ultrasonic power and concentrations of HCl and NaOH, are studied to understand the leaching mechanism of the refractory gold concentrate. The gold leaching recovery of 98% in the anode compartment is more than double than that of 46% in the cathode compartment. The leaching kinetics is analysed by using a shrinking rim model given by: 1?(1?X)^1/3?=?kt and 1?3(1?X)^2/3+2(1?X)?=?kt. The kinetics appears to be chemically controlled in the anode compartment and to be diffusively controlled in the cathode compartment respectively. Surface examinations of the samples leached in electro-oxidation and ultrasonic electro-oxidation conditions are carried out by X-ray diffraction and scanning electron microscopy. These results can be considered as a basic understanding for leaching refractory gold concentrate by ultrasonic electro-oxidation.

On a examiné le comportement de lixiviation ultrasonique de concentré d’or réfractaire, simultanément à l’anode, en solution d’acide chlorhydrique, et à la cathode, en solution d’hydroxyde de sodium. Pour ces expériences, on emploie un réacteur électrochimique divisé en trois compartiments (compartiment de l’anode, du milieu, et de la cathode) par une membrane d’échange d’anion et de cation. On a étudié divers paramètres, incluant le rapport solide-liquide, la densité de courant, la température de lixiviation, la taille de particule, la puissance ultrasonique, et la concentration de HCl et de NaOH, afin de comprendre le mécanisme de lixiviation du concentré d’or réfractaire. La récupération de l’or, par lixiviation, de 98% dans le compartiment de l’anode est plus que le double de celui de 46% du compartiment de la cathode. La cinétique de lixiviation est analysée avec le modèle du retrait de la bordure donné par: 1?(1?X)^1/3?=?kt et 1?3(1?X)^2/3+2(1?X)?=?kt. La cinétique est contrôlée par la chimie dans le compartiment de l’anode et par diffusion dans le compartiment de la cathode, respectivement. L’examen de la surface des échantillons lixiviés sous des conditions d’électro-oxydation ou d’électro-oxydation ultrasonique est effectué par XRD (diffraction des rayons X) et par SEM (microscopie électronique à balayage). On peut considérer ces résultats comme base de la compréhension de la lixiviation de concentré d’or réfractaire par électro-oxydation ultrasonique.     

Scientific and Technological Challenges in Mineral Processing

Due to increasingly complex mineralogy, steadily decreasing ore grades and ever increasing economic and environmental pressures, the mineral processing industry over the past decade had to evolve appropriate means to treat these difficult-to-process ore deposits. Some of the important emerging trends and the evolutionary changes which have occurred in mineral processing technology; are reviewed. This includes the areas of quantifying mineral liberation, in the design of new size reduction devices like high pressure rolls mills, advances in gravity separation and magnetic separation, development of new flotation machines like column flotation and flash flotation, design and testing of new flotation reagents and the new technologies based on a combination of physical and chemical separation methods are reviewed. The challenging areas of current research efforts have been highlighted.     

Studies on the Kinetics of Carbon Tetrachloride Chlorination of Refractory Metal Oxides

Abstract

Studies on the kinetics of chlorination of the oxides of titanium, zirconium, niobium and tantalum by carbon tetrachloride gas in dilution with nitrogen, at low and moderate temperatures, have been carried out. In each case, the effect of time, temperature, partial pressure of carbon tetrachloride and the particle size, on the chlorination of the oxide, has been studied. The influence of some physico-chemical properties of the oxides and their halides on the kinetics process, has been discussed. The chlorination results below and above the dissociation temperature of carbon tetrachloride ( ～ 773 K.) have been examined to find out the difference in the kinetics by CC1₄ and those by elemental carbon and chlorine. From these kinetics results, the mechanism of the chlorination of each of the oxides, has been established and compared. The optimum experimental conditions for preparing the metal chlorides, keeping in view of the maximum utilisation of the carbon tetrachloride, have been established. The merits of carbon tetrachloride as a chlorinating agent, have been highlighted. From these kinetics results, the scope for chlorinating the refractory metal oxides, as well as their mixed oxides, at lower temperatures and lower partial pressures of carbon tetrachloride, with the scope for recycling the reagent, has been briefly discussed. Some preliminary results on the preferential chlorination of these oxides by carbon tetrachloride present in a typical tin slag, have been presented, to further substantiate the merits of carbon tetrachloride as a low temperature chlorinating agent.