国外难处理金矿热压氧化工艺条件分析

针对国外热压氧化工艺条件进行了分析,并重点分析讨论了热压氧化预处理金矿的工艺矿物类型、热压氧化温度及压力,总结了热压氧化工艺具有的诸多优点。国外热压氧化技术和设备比较成熟,因此已成为国外难处理金矿预处理的首选工艺。     

Kinetics of Dissolution of Tenorite in Ammonium Media

In this work, the dissolution kinetics of tenorite (CuO) in a NH₄OH-H₂O system was studied. The studied temperature range was 5–55°C, ammonium hydroxide concentration between 0.1 and 0.75 M, and a particle size range of 5–24 µm. The stirring speed, pH of the ammonia solution, and various agents were also studied. The results indicated that the leaching of tenorite occurred quickly with a particle size of 5 µm in a 0.45 M solution of NH₄OH for a pH value equal to 10.5. Dissolution of CuO also increases as temperature and the concentration of NH₄OH increase. For concentrations less than 0.10 M, there is almost no leaching tenorite. By decreasing the particle size, the dissolution of CuO increase. Results show the stirring speed had no significant effect on the leaching rate of tenorite for values above 250 rpm. Leaching kinetics was analyzed using the model of the surface chemical reaction. The reaction rate was of the order of 2.2 with respect to the concentration of ammonium hydroxide and inversely proportional to the initial particle size. Activation energy of 59 kJ/mol was estimated for the temperature range of 5–55°C.     

THE HYDROMETALLURGICAL EXTRACTION OF ZINC BY AMMONIUM CARBONATE: A REVIEW OF THE SCHNABEL PROCESS

The use of ammonium carbonate for the extraction of metals such as copper and nickel is well known. Less well known is the fact that ammonium carbonate extraction was used for the commercial recovery of zinc decades before its application to either copper or nickel. This article reviews the published data on the Schnabel Process (the hydrometallurgical extraction of zinc by ammonium carbonate) covering the period of 1880–2005.     

浅析高冰镍氯气浸出制取镍电解初液

氯气浸出工艺是当前世界上先进的高镍锍精炼工艺之一,在镍的回收率、生产率、产品质量及工作环境等方面具有较突出的优势.氯化湿法冶金由于具有高反应速率、高浸出率、以及灵活的金属提取工艺组合等优点,成为一项重要的湿法冶金新技术,以往制备镍电解初液的工艺都采用硫酸常压选择性浸出-加压浸出工艺,这样的工艺具有浸出效率低、工艺设备复杂、流程长、作业强度高、生产成本高等缺点.为了解决这些不利的因素,现在学者都在探索氯化浸出工艺替代硫酸选择性浸出工艺.本文就氯气浸出生产镍电解初液的工艺原理、试验过程、试验结果及其优点进行了充分的阐述.     

含氮氧化物废气处理技术应用

某黄金冶炼公司自主研发了“NHSNCR-新型高效SNCR”集成脱硝技术,处理银泥湿法精炼中产生的含氮氧化物废气.结果表明,处理后含氮氧化物废气中NOx浓度可降低到17.9 ～41.5 mg/m3,NOx净化效率达到99％,尾气NOx浓度远低于国家排放标准.该技术具有设备简单、操作简便,净化效率高,经济效益显著等优点.     

锑冶炼砷碱渣水热浸出脱砷回收锑试验研究

锑冶炼过程中产生的砷碱渣含有大量的锑和砷,将炼锑含砷碱渣进行水热浸出回收锑和脱砷处理,锑回收率和砷浸出率分别达到80％、92％以上,有效实现了砷锑分离。     

硫化锌精矿常压直接浸出技术现状

在广泛收集整理国内外硫化锌精矿直接浸出技术资料的基础上,对常压直接浸出技术原理、工艺过程及设备进行了介绍和评述,指出常压直接浸出技术是现有锌系统技术改造、实现扩产及锌浸出渣资源循环利用的优选方案之一.     

硫化锌精矿低温低压中和除铁试验研究及生产应用

试验研究了在低温低压条件下将硫化锌精矿作为中和剂对一段加压酸浸液进行中和除铁,在一定的中和温度、中和时间、氧分压、浸出前液铁离子浓度、液固比等的条件下,较好的实现了在低温除铁,有效解决硫磺的包裹问题,硫的氧化率降低,且以元素硫的形式进入渣中,后液达到了净化除铁前液的标准要求,可供净化除铁使用。     

降低氨浸渣中钼含量的研究

对传统工艺制备钼酸铵的酸洗、氨浸工艺进行研究,确定氨浸渣中钼含量高低的主要影响因素。通过试验研究,降低氨浸渣中钼含量。     

对我国电镍生产工艺的分析与改进研究

对我国电镍生产主要工艺存在的问题进行分析,并提出工艺改进方案。在现有不溶阳极电积精炼工艺基础上,采用常压浸出渣添加焙砂加压选择性浸出固定硫、浸铜后渣电炉还原熔炼、产出的铜镍锍用返液及镍和铜电积的阳极液分段浸出等措施解决现有工艺的内在矛盾和缺陷,提高对原料成分波动的适应性,分阶段集中和提高各有价金属的回收率。