Relationship between copper content of slag and matte in the SKS copper smelting process

In the newly developed oxygen-enriched bottom-blowing copper smelting process(also known as the SKS copper smelting process), Cu loss in slag is one of the most concerning issues. This paper presents our research results concerning the relationship between the Cu content of the matte and slag in the SKS process; the results are based on actual industrial production in the Dongying Fangyuan copper smelter. The results show that the matte grade strongly influences Cu losses in slag. The dissolved and entrained losses account for 10%–20% and 80%–90% of the total SKS industrial Cu losses in slag, respectively. With increasing matte grade, the dissolved and entrained Cu losses in the SKS slag both increase continuously. When the matte grade is greater than 68%, the content of Cu in the smelting slag increases much more dramatically. To obtain a high direct recovery of copper, the matte grade should be less than 75% in industrial SKS copper production.

Multiphase equilibrium modeling of oxygen bottom-blown copper smelting process

A computational thermodynamics model for the oxygen bottom-blown copper smelting process(Shuikoushan,SKS process)was established,based on the SKS smelting characteristics and theory of Gibbs free energy minimization.The calculated results of the model show that,under the given stable production condition,the contents of Cu,Fe and S in matte are71.08%,7.15%and17.51%,and the contents of Fe,SiO2and Cu in slag are42.17%,25.05%and3.16%.The calculated fractional distributions of minor elements among gas,slag and matte phases are As82.69%,11.22%,6.09%,Sb16.57%,70.63%,12.80%,Bi68.93%,11.30%,19.77%,Pb19.70%,24.75%,55.55%and Zn17.94%,64.28%,17.79%,respectively.The calculated results of the multiphase equilibrium model agree well with the actual industrial production data,indicating that the credibility of the model is validated.Therefore,the model could be used to monitor and optimize the industrial operations of SKS process.

Intelligent prediction model of matte grade in copper flash smelting process

Due to the importance of detecting the matte grade in the copper flash smelting process, the mechanism model was established according to the multi-phase and multi-component mathematic model. Meanwhile this procedure was a complicated production process with characteristics of large time delay, nonlinearity and so on. A fuzzy neural network model was set up through a great deal of production data. Besides a novel constrained gradient descent algorithm used to update the parameters was put forward to improve the parameters learning efficiency. Ultimately the self-adaptive combination technology was adopted to paralleled integrate two models in order to obtain the prediction model of the matte grade. Industrial data validation shows that the intelligently integrated model is more precise than a single model. It can not only predict the matte grade exactly but also provide optimal control of the copper flash smelting process with potent guidance.

SELECTION OF THE PROCESS PARAMETERS FOR BATH AUTOGENOUS SMELTING OF COPPER

The process parameters for bath autogenous smelting of copper were selected based on dynamic analysis of the experimental data and calculation of the mathematical model. Selecting the slag composition of SiO2/Fe=0.80 and CaO％=16. desulphur ratio less than 80 wt.-％ in system. and the copper content of matte less than 60 wt.-％, it is able to limit Fe3O4 formation and obtain a high desulphurization. The critical oxygen content of the blast increased with decrease of the sulphur content of the concentrate and increase of copper contents of the matte. If the copper contents of the concentrate are respectively of 30 and 35 wt.-％, the critical oxygen contents of the blast will be 48 and 69 wt.-％ respectively. The smelling rate increases linearly with the blast intensity. When the sulphur content of the concentrate is 30 wt.-％, the oxygen content of the blast 70 vol.-％ and the copper content of the matte 60 wt.-％, a blast intensityy of 700 Nm3/m2·h results in a smeling rate of 48.81 t/m2·d.

Copper smelting mechanism in oxygen bottom-blown furnace

The SKS furnace is a horizontal cylindrical reactor similar to a Noranda furnace,however,the oxygen enriched air isblown into the furnace from the bottom.Mechanism model of the SKS process was developed by analyzing the smeltingcharacteristics deeply.In our model,the furnace section from top to bottom is divided into seven functional layers,i.e.,gas layer,mineral decomposition transitioning layer,slag layer,slag formation transitioning layer,matte formation transitioning layer,weakoxidizing layer and strong oxidizing layer.The furnace along the length direction is divided into three functional regions,that is,reaction region,separation transitioning region and liquid phase separation and settling region.These layers or regions play differentroles in the model in describing the mechanism of the smelting process.The SKS smelting is at a multiphase non-steady equilibriumstate,and the oxygen and sulfur potentials change gradually in the length and cross directions.The smelting capacity of the SKSprocess could be raised through reasonably controlling the potential values in different layers and regions.

Breaking the Fe_(3)O_(4)-wrapped copper microstructure to enhance copper-slag separation

The precipitation of Fe_(3)O_(4)particles and the accompanied formation of Fe_(3)O_(4)-wrapped copper structure are the main obstacles to copper recovery from the molten slag during the pyrometallurgical smelting of copper concentrates.Herein,the commercial powdery pyrite or anthracite is replaced with pyrite-anthracite pellets as the reductants to remove a large amount of Fe_(3)O_(4)particles in the molten slag,resulting in a deep fracture in the Fe_(3)O_(4)-wrapped copper microstructure and the full exposure of the copper matte cores.When 1wt%composite pellet is used as the reductant,the copper matte droplets are enlarged greatly from 25μm to a size observable by the naked eye,with the copper content being enriched remarkably from 1.2wt%to 4.5wt%.Density functional theory calculation results imply that the formation of the Fe_(3)O_(4)-wrapped copper structure is due to the preferential adhesion of Cu_(2)S on the Fe_(3)O_(4)particles.X-ray photoelectron spectroscopy,Fourier transform infrared spectrometer(FTIR),and Raman spectroscopy results all reveal that the high-efficiency conver-sion of Fe_(3)O_(4)to FeO can decrease the volume fraction of the solid phase and promote the depolymerization of silicate network structure.As a consequence,the settling of copper matte droplets is enhanced due to the lowered slag viscosity,contributing to the high efficiency of copper-slag separation for copper recovery.The results provide new insights into the enhanced in-situ enrichment of copper from mol-ten slag.

某冶炼铜渣综合回收铜铁的实验研究

这是一篇冶金工程领域的论文。某铜冶炼渣浮选尾渣中铁品位为37.42%,铜品位为1.86%,根据其矿石性质特点,采用烟煤作为还原剂,应用直接还原焙烧-磁选工艺回收铜尾渣中铜铁,实验结果表明:将铜冶炼渣、烟煤和生石灰(作为助还原剂)按100∶25∶20的质量比混合,在焙烧温度定1 200℃,时间为80 min,磨矿细度为-0.045 mm 80%,磁场强度为0.139 T条件下可获得铁品位为90.98%,铁回收率为90.13%,铜品位为5.82%、铜回收率为87.38%的含铜铁精矿,实现了冶炼渣铜中铜铁的综合回收。

铜火法冶炼废水处理实践

阐述了铜冶炼火法工艺发展状况,剖析了铜冶炼过程产生废水的主要环节,并对废水处理工艺及原理进行了梳理,分析了某铜冶炼企业废水产生节点、产生特点和组成成分;针对现有的废水处理技术和资源化利用提出了合理的建议。特别阐述了阳谷祥光铜业自主研发的旋浮铜冶炼技术、粗铜自氧化还原精炼技术、平行流电解技术,“硫化+石膏+中和”工艺和废水深度处理联合工艺特点,对采用火法冶炼工艺的铜冶炼企业的废水处理及资源化利用具有借鉴意义。

顶侧复合连续炼铜系统开发之工艺流程再造

富氧顶吹浸没熔炼工艺是在特定时期引进并在国内实现消化创新和广泛应用的铜冶炼技术,为我国铜冶炼行业从传统熔炼工艺向现代强化熔炼工艺的跨越作出重要贡献。近年来,连续炼铜技术和短流程技术快速发展,造锍熔炼在高富氧浓度、高铜锍品位、高温和高处理能力方向上不断突破。在高质量发展要求和技术快速进步的背景下,国内各生产企业结合自身实际围绕铜冶炼系统的绿色节能降耗开展了系列探索和研究,取得了一系列成果。本文围绕新时期铜精矿富氧顶吹浸没熔炼工厂技术升级改造的工艺创新与流程再造进行探索,提出总体思路和开发方向,包括主体设备供风装置增加侧吹喷枪,并对冶金炉炉体结构及其他配套设施进行相应的改造,取消原料制粒系统和沉降电炉,实现高品位铜锍冶炼和连续炼铜,以期为顶吹熔池熔炼工厂技术和装置的升级改造提供技术储备、指导及参考,推动行业向低碳、绿色、环保方向迈进。

铜冶炼烟尘金属分离及资源回收研究进展

以铜冶炼烟尘为研究对象,分析其理化及矿物学性质,对比铜冶炼烟尘金属分离与回收方法,包括碳热还原法、硫酸浸出法、碱性浸出法和湿法-火法联合工艺,总结各方法的原理、典型工艺、现状和存在问题,阐述非常规冶金方法在铜冶炼烟尘金属分离中的应用,展望铜冶炼烟尘资源回收的发展方向。研究结果表明:铜冶炼烟尘中砷、铜、锌含量受冶炼工艺、原矿品质的影响,不同元素赋存形态存在差异。碳热还原法可以通过金属砷酸盐和氧化物分解的方式释放砷,从而实现砷与其他有价金属的分离;硫酸浸出法可以高效浸提铜冶炼烟尘中的金属,实现多元素的回收;碱性浸出法可选择性浸提砷;湿法-火法联合工艺结合了火法工艺选择性分离砷和湿法工艺高效提取金属的优点,对于复杂高砷铜冶炼烟尘处理具有优势。铜冶炼烟尘兼具资源属性和环境风险,实现清洁生产及多金属资源化利用仍是关键,砷的无害化处置与锌、铜、铅等有价金属的高效协同回收工艺及分离机制、全过程物质流与环境效应是铜冶炼烟尘资源回收的发展方向。

多枪顶吹连续吹炼过程中喷枪排布方式的数值模拟

多枪顶吹连续吹炼工艺因其低空污染小、炉衬寿命长、连续化程度高等优点而备受冶金行业瞩目。以工业冶金炉窑为研究对象,基于计算流体力学,对多枪顶吹连续吹炼炉内气-渣-铜锍多相混合流场进行了数值模拟。探索了多枪单排布置和交错式布置对炉内流场、湍动能和气含率的影响。研究表明,相较于双排交错式喷枪布置方案,单排布置具有更强的搅拌能力、较大的熔池横向及纵向扩散范围,以及更小的静态区域体积。此外,喷枪单排布置方案下的气含率始终高于双排交错布置,证明了单排的喷枪排布方式有利于渣层搅拌效率的提高,加速铜沉降,降低生产能耗。

砷在富氧底吹炼铜过程中的走向及物相结构

采用Factsage热力学分析、元素分析、XRD、SEM−EDS及金相显微镜等手段研究了富氧底吹炼铜工艺中砷的走向和物相结构。结果表明:通过适当降低富氧浓度,可以提高熔炼温度增加烟气和烟尘中砷的分配。混合炉料中砷主要存在于毒砂和砷黝铜矿中,少部分存在于返渣的冰铜相和细烟尘中;冰铜中砷主要以含砷锑冰铜形式存在,平均砷含量为4.75%(质量分数);粗铜中砷主要与铜、锑、铅等形成固溶体,平均砷含量为7.78%;底吹炉渣中砷主要分布于渣相所含的含砷锑冰铜(26.38%)中,少部分存在于玻璃相基底(1.73%)和铁橄榄石相(2.08%)中;磁选前渣中砷主要存在于渣中的复杂含砷冰铜相中,大部分被渣包裹,平均砷含量为37.26%。

基于GRNN算法的铜阳极炉精炼还原终点预报模型

针对阳极炉炼铜还原期终点判断依赖人工判断的局限,利用机器学习技术实现智能判断。通过图像去模糊处理优化图像特征,对图像进行灰度差分矩阵运算,将矩阵中提取出的特征值作为神经网络的输入,构建了一种新的铜阳极炉精炼还原期终点判断模型。试验结果显示,在真实生产环境下,采用GRNN算法对还原终点进行预测,有助于消除铜阳极炉精炼过程中不同指标之间的相关性,减少了数据冗余和系统误差,使预测精度提高至96.54%。相较于传统方法,这种新的判断模型有效提高了阳极炉炼铜还原期终点判断的准确性。

富氧双侧吹铜熔池熔炼炉上升烟道结渣的矿物学分析

富氧双侧吹铜熔池熔炼炉上升烟道烟尘结渣严重,阻塞烟道,是制约熔炼炉长周期高负荷高作业率生产的关键因素。分别利用X射线荧光光谱仪、X射线衍射仪、扫描电子显微镜和电子探针显微分析仪,研究富氧双侧吹铜熔池熔炼炉上升烟道结渣烟尘的化学成分、物相组成及微观形貌。结果表明,上升烟道烟尘的主要元素为Fe、Cu、Pb、Zn和O,主要物相是(Cu, Zn, Fe)Fe_(2)O_(4)和Fe_(3)O_(4),表面微观形貌呈致密无孔洞。结合生产过程工况条件,对烟道结渣原因进行分析,认为富氧双侧吹铜熔池熔炼炉生产过程中,富氧空气通过喷嘴鼓入炉内,强烈搅动熔体,熔体中的气泡破裂逸出,喷溅形成的小颗粒熔渣与冰铜被热气流带入上升烟道,熔渣与冰铜被氧化为高熔点的(Cu, Zn, Fe)Fe_(2)O_(4)和Fe_(3)O_(4),在烟道壁面遇冷凝结形成结渣;同时,熔炼炉负压运行,入炉原料水分低,铜精矿等未反应的粉料被烟气带入到上升烟道高温段,在氧化气氛下反应生成黏结结渣;此外,原料中Pb、Zn、As等易挥发性物质进入烟道,被氧化为低熔点化合物后与高熔点的(Cu, Zn, Fe)Fe_(2)O_(4)和Fe_(3)O_(4)黏结在一起,形成致密的结渣烟尘。因此,在冶炼生产中,建议通过控制入炉原料水分和杂质含量,减少粉料入炉;控制渣型和熔炼温度,减少熔体喷溅;使用喷嘴燃烧重油,烧熔结渣烟尘,保证生产正常稳定运行。

某铜冶炼渣浮选回收铜工艺试验研究

对某含铜2.70%的铜冶炼渣进行了浮选回收铜的试验研究。结果表明,浮选过程中添加硫化钠作为调整剂,并采用中矿集中再选后尾矿分级的工艺流程,可减少一段扫选,降低中矿含泥量,闭路试验获得了铜品位20.59%、回收率91.75%的铜精矿,综合尾矿铜品位降至0.26%。

内蒙古某铜冶炼炉渣选矿厂流程确定、设计与生产实践

内蒙古赤峰某铜冶炼炉渣主要为侧吹-连续吹炼炉渣,缓冷后铜主要以硫化铜的形式存在,铁主要以磁铁矿和铁橄榄石的形式存在。为了确定选矿厂的流程、设备、产品指标等关键工艺技术及设备信息,通过对比粗碎—半自磨—球磨方案与三段一闭路破碎—球磨方案的优劣,最终确定了包含半自磨的碎磨工艺;通过参考类似选矿厂的实践和技术的先进性、稳定性、可操作性,确定了选矿厂全流程及设备规格型号和数量,并设计了产品指标。生产实践表明,铜冶炼炉渣选矿系统的铜精矿铜品位、回收率及尾矿品位等关键指标均优于设计值,实现了全面达产、达标。

白银炼铜法工艺优化思路

白银炉攻关团队系统对比其它先进铜熔炼工艺优缺点并科学评判“白银炼铜法”铜熔炼工艺存在的问题,通过炉型优化、氧气浓度提升等一系列试验和改造,实现了我国唯一原创具有自主知识产权的“白银炼铜法”炉床面积增大至106 m^(2),单炉粗铜冶炼能力超过了20万t,各项指标达到了同行业先进水平。

白银熔池熔炼炉稀氧燃烧技术工业实践

借鉴阳极炉使用稀氧燃烧技术的成功应用经验,在白银炉沉淀区采用稀氧燃烧,解决了富氧燃烧时粉煤消耗较多、烟气量大、炉膛温度分布不均匀等问题,而且延长了耐火材料的寿命,改善了作业环境。

某铜冶炼多种堆存炉渣选矿试验研究

长期以来,堆存的铜冶炼炉渣在占用了大量的土地资源的同时也污染了环境,且炉渣中所含的铜金属没有得到很好的回收利用。为了提高二次资源综合利用率,减少冶炼所产生的固体废弃物对环境的污染等制约发展的问题,对某厂不同渣型的炉渣进行详细的选矿试验研究,并确定了工艺方案和选矿流程。

铜阳极泥选冶联合工艺有价金属走向考察及改进建议

铜阳极泥是资源综合回收的优选对象,分析各有价金属的分散情况对后续的回收有着指导性的方向作用。铜阳极泥选冶联合工艺较为成熟,具有不断外延拓展金属回收的空间。针对4000 t铜阳极泥物料的生产数据,考察了该工艺有价金属的走向,统计分析了金、银、硒、碲、铅、锑、铋、铜等在工艺流程中的分布率,摸清了有价金属主要分散情况。分析表明,金、银、硒、碲最大的分散点均为浮选尾矿,分别占分散总量的67%、37%、34%、58%,确定为重点管控对象。并结合统计分析结果对提高金、银、硒、碲回收率及铅、锑、铋、铜的回收提出了改进建议。