在细粒分选中表面现象的作用

在阿尔登馆举行的国家科学基金专题讨论会上首次讨论了细粒选矿问题(Somasu-ndaran 和 Fuerstenau 1976),迄今已快十年了。现在细粒选矿和过去一样,仅存在许多问题。在许多矿石的选别过程中,有20%到50%的有用矿物我们还没有办法回收。尽管细粒选矿的问题仍是如此严重,但我认为,就细粒难选的原因来说,我们的观点已经发生了变化。尽管我们还没有见到这个领     

石煤空白焙烧过程热力学分析

从热力学上对石煤空白焙烧过程中发生的相关氧化反应进行了分析.有机碳、黄铁矿及钒的氧化反应,在热力学上都可自发进行,有机质和黄铁矿比钒更容易氧化.有机碳和黄铁矿的存在,对钒的氧化有阻碍作用,若预先脱碳或脱除黄铁矿,则有利于钒的氧化.     

Kinetics of nickel leaching from roasting-dissolving residue of spent catalyst with sulfuric acid

Sulfuric acid leaching process was applied to extract nickel from roasting-dissolving residue of a spent catalyst, the effect of different parameters on nickel extraction was investigated by leaching experiments, and the leaching kinetics of nickel was analyzed. The experimental results indicate that the effects of particle size and sulfuric acid concentration on the nickel extraction are remarkable; the effect of reaction temperature is mild; while the effect of stirring speed in the range of 400–1 200 r/min is negligible. Decreasing particle size or increasing sulfuric acid concentration and reaction temperature, the nickel extraction efficiency is improved. 93.5% of nickel in residue is extracted under suitable leaching conditions, including particle size (0.074–0.100) mm, sulfuric acid concentration 30% (mass fraction), temperature 80 °C, reaction time 180 min, mass ratio of liquid to solid 10 and stirring speed 800 r/min. The leaching kinetics analyses shows that the reaction rate of leaching process is controlled by diffusion through the product layer, and the calculated activation energy of 15.8 kJ/mol is characteristic for a diffusion controlled process. Foundation item: Project (50574101) supported by the National Natural Science Foundation of China; Project (2003UDBEA00C020) supported by the Collaborative Project of School and Province of Yunnan Province, China     

基于自组织神经网络的烧结终点自适应预报系统的开发

烧结终点的在线检测和提前预报对于稳定终点,进而提高烧结矿强度和产量、降低能耗有重要意义。文章介绍了烧结终点的软测量方法;提出了一个新的预报参数——风箱废气温度曲线拐点;将多层前向人工神经网络应用于烧结终点的预报,对BP算法做了较大改进,使学习算法可以自组织神经网络的结构。应用这些技术开发的烧结终点自适应预报系统能够快速、准确地判断和预报烧结终点的状态,可用于在线操作指导或作为自动控制的依据。     

石英与蛇纹石异相凝聚及其对黄铁矿浮选的影响

通过单矿物和人工混合矿的浮选试验、Zeta电位测试、吸附量测试,研究了蛇纹石和石英异相凝聚的机理,以及对黄铁矿浮选的影响,以进一步探索多种矿物的体系中,蛇纹石对硫化矿物浮选影响的主要原因。结果表明:通过添加石英,可以恢复黄铁矿对捕收剂的吸附量,减弱蛇纹石的不良影响,不同粒级的石英与蛇纹石的异相凝聚作用强弱不同,粒级越细的石英,与蛇纹石的异相凝聚作用越强。     

方铅矿表面上元素硫的作用与行为

用醋酸—醋酸铵溶液处理方铅矿可以脱除方铅矿表面上的氧化物,同时产生0.89个单分子层的元素硫(S~o)。浮选试验表明方铅矿表面上元素硫量的多少与方铅矿的无捕收剂浮选行为有很好的对应关系并决定方铅矿无捕收剂浮选速率和最大回收率。浮选试验、XPS和环已烷—气相色谱测定表明:方铅矿表面上的元素硫可以被氧化或还原,方铅矿在碱性介质中的主要氧化产物是硫代硫酸铅。     

钽铌矿捕收剂的研究

采用苯甲羟肟酸、C_(7～9)羟肟酸和油酸分别对钽铌矿、石英、长石三种纯矿物进行可浮性研究。结果表明:苯甲羟肟酸对钽铌矿有较强的选择捕收能力,在pH6.0～10.0范围内捕收效果最好,苯甲羟肟酸与辅助捕收剂WT_2以质量比3:1组合使用时,提高了分选指标,起到了“1+1>2”的协同效果。     

New technique of comprehensive utilization of spent Al2O3 -based catalyst

A new technology was developed to recover multiple valuable elements from the spent Al2O3-based catalyst by X-ray phase analysis and exploratory experiments. The experimental results show that in the condition of roasting temperature of 750 ℃ and roasting time of 30 min, molar ratio of Na2O to Al2O3 of 1.2, the leaching rates of alumina, vanadium and molybdenum in the spent catalyst are 97.2%, 95.8% and 98.9%, respectively. Vanadium and molybdenum in sodium aluminate solution can be recovered by precipitators A and B, and the precipitation rates of vanadium and molybdenum are 94. 8% and 92. 6%. Al（OH）3 was prepared from sodium aluminate solution in the carbonation decomposition process, and the purity of Al2O3 is 99. 9% after calcination, the recovery of alumina reaches 90. 6% in the whole process; the Ni-Co concentrate was leached by sulfuric acid, a nickel recovery of 98. 2% and cobalt recovery over 98.5% can be obtained under the experimental condition of 30% H2SO4, 80 ℃, reaction time 4 h, mass ratio of liquid to solid 8, stirring rate 800 r/min.     

氧化铜矿浮选研究进展

详细评述了氧化铜矿的浮选方法与工艺及浮选药剂研究进展,指出强化硫化过程、硫化质量和寻找具有高度选择性的捕收剂是其重要的研究方向     

纤蛇纹石的盐酸浸出及其动力学模型研究

研究了纤蛇纹石盐酸浸出过程中影响浸出率的主要因素,通过单因素实验确定最佳浸出条件为:盐酸浓度2 mol/L,温度95～100℃,浸出时间3 h,液固比60.进而通过建立液-固相反应纤维状颗粒的宏观动力学模型,研究了纤蛇纹石盐酸浸出的动力学过程.依据此模型所求得的反应表观活化能为24.4 kJ/mol,与用等浸出率法求得的值25.4 kJ/mol基本一致.动力学研究结果表明纤蛇纹石的盐酸浸出过程受扩散控制.