【作者】 谢锴；

【导师】 梅炽；

【作者基本信息】 中南大学 ， 热能工程， 2006， 博士

【摘要】 现代铜闪速熔炼炉发展中若干理论与操控优化问题的研究，对闪速熔炼技术的突破、提高铜回收率、提升国内铜冶炼企业盈利水平以及国际市场竞争力具有重要的现实意义。通过对闪速炉反应塔内工艺物料颗粒较全面的分析检测和总结前人研究成果，通过从微粒运动学、动力学、两相流体力学以及统计分析和归纳等方面的论证，提出了新的闪速熔炼模型——粒子脉动碰撞模型（PPC Model）。在闪速炉悬浮熔炼过程中粒子既存在分裂行为，又存在碰撞和聚合过程，精矿粒子的分裂和碰撞聚合是一对矛盾的统一体。粒子分裂是精矿快速氧化反应的结果，也加速了粒子脉动，而精矿粒子脉动正是粒子碰撞聚合主要原因；粒子聚合使氧化脱硫反应继续，是固液相之间氧传递的重要机制。粒子脉动碰撞模型具体表述如下：（1）在闪速炉反应塔不同高度上，精矿粒子的分裂和颗粒群内粒子脉动碰撞过程同时存在；（2）通过系统地论证分析高强湍流喷射流中粒子群的脉动与碰撞机制，提出精矿粒子脉动是粒子碰撞聚合主要原因；（3）随着氧化反应的进行，在颗粒中心形成熔融硫化物和SO₂气泡，颗粒外表面是多孔的氧化铁壳；熔融核中气相的生成促使粒子分裂和脉动，氧气浓度和当地温度越高，这一过程越强烈；（4）反应塔中由于粒子的大小、粒子的成分、粒子的周围的氧气浓度和粒子温度的不同，导致各粒子之间的氧化程度差别极大。氧化反应放出的热量使精矿粒子熔化；欠氧化粒子未完成脱硫反应；（5）过氧化粒子在反应塔中下降时，它们彼此之间、或者与反应慢的欠氧化粒子相碰撞，聚合长大，同时过氧化颗粒被欠氧化粒子还原。通过反应动力学和反应热力学分析确定，悬浮熔炼过程主要反应有：铜精矿着火燃烧反应、过氧化反应、碰撞还原反应、二次氧化反应、造渣反应和燃料燃烧反应，并以此建立了闪速熔炼仿真的数学模型。通过直接验证、逻辑验证和间接验证三种方式论证了本仿真模型的合理性和可靠性。本研究对炉渣中的铜损失形态进行了检验分析，并进行了沉淀池工业考察和炉内熔体的垂直取样，分析了炉结形成的主要原因。通过对金隆闪速炉生产数据的统计分析，研究炉渣带走铜所占百分率（或渣含铜）与铜精矿处理量、铜锍品位、炉渣成分（铁硅比）、渣层厚度和渣中Fe₃O₄含量等参数之间的关系，并提出降低弃渣含铜损失要重点控制闪速熔炼中Fe₃O₄行为的观点和技术路线。针对如何强化闪速熔炼的同时减少Fe₃O₄生成量，提出了在反应塔——沉淀池——贫化电炉系统中建立明显的氧势梯度，实行“氧势梯度熔炼”制度。通过在反应塔顶加入适量固体还原剂——焦粉（或煤粒），可以形成必要的氧势梯度，从而可实现在熔炼强化的同时，降低Fe₃O₄的生成量。通过闪速炼铜数字仿真试验得到了减少Fe₃O₄生成量优化工况。最后，对超强化闪速熔炼精矿喷嘴新结构进行了仿真研究与开发。它是一种旋流喷嘴，通过采用不同的旋流数可以改变火焰的形状和反应过程。超强化闪速熔炼可将现有的闪速炉的最大生产能力提高3～4倍。一系列仿真试验证明，若铜精矿采用气力输送的方式送入炉内，并且通过主要操作参数的优化匹配可成功实现超强化喷嘴的设计理念和目的。更多还原

【Abstract】 The research on several theory and operation optimizationchallenges in the development of modern copper flash smelters would bevery important for breaking through the technical difficulties of flashsmelting, increasing the copper recovery, upgrading the domesticsmelteries’ profit and competition ability in the international market.A new flash smelting theory—Particle Pulsation Collision Modelwas presented with overall analysis on the reacting particles in the shaftof the flash smelter, with conclusions of the former research results, andwith the proving from micro-particle kinematics, dynamics, two-phasefluid dynamics, statistic analysis and conclusion. Both the particlesplitting and the collision occur in the process of suspend smelting, whichare the two-side of the union of conflict. The particle splitting is the resultof rapid oxidation of the concentrate; meanwhile it results in intensifyingthe particle pulsation, which is the main cause of the particle collision.The particle gathering makes the oxidation and desulfurization reactioncontinue, which is the main mechanism of the oxygen transfer betweensolid and liquid phases. The specific statements on the Particle PulsationCollision Model are as follows.（1） The particle splitting and collision co-exist at different height ofreacting shaft.（2） It is presented that the concentrate particle pulsation is the mainreason for particle collision and gathering with the analysis on pulsationand collision of the high intensive turbulent jet of particle group.（3） With the oxidation continuance, melted sulphide and SO₂bubbles are formed at the particle center. The out-surface of the particle isporous ferric oxide shell. The gas formation in melting core impels theparticle splitting and collision. The higher the oxygen concentration andthe particle temperature are, the intenser the process is.（4） Because of the difference of the sizes, components, surroundingoxygen concentration and temperature of the particles, particles’oxidation have much difference. The heat released from the oxidation melts the concentrate particles, and the desulfurizations of under-oxidizedparticles are not completed.（5） While dropping in the shaft, the over-oxidized particles collideeach other or with the under-oxidized particles and gather to becomebigger. At the same time, the over-oxidized particles are deoxidized bythe under-oxidized particles.With analyzing the reaction dynamics and thermodynamics, it isconfirmed that the process of suspend smelting is made up of concentratecombustion, over-oxidization, collision and reducing reaction,re-oxidization, slagging reaction and fuel combustion. The numericalsimulation model of the flash smelter is set up, whose rationality andreliability have been proved by direct, logic and indirect methods.In this dissertation, the form of copper loss in the slag had beentested and analyzed. The melted matter at the different heights was takenout, and the industry examination of settler’s working condition wasperformed for the analysis of main reason of the scar formation. Therelationships between copper lose percentage （or copper in slag） andsmelting capacity, copper matte grade, the slag component （Fe/SiO₂）,slag thickness and Fe₃O₄ content were worked out on the basis ofstatistics analysis on Jinlong copper flash smelter’s data. The viewpointand technical scheme was presented, which the Fe₃O₄ content must becontrolled for reducing the copper loss.For controlling the Fe₃O₄ content and intensifying the flash smelting,Gradient Oxygen Distribution Smelting Method is presented, which is toset up obvious oxygen gradient in the system of shaft, settler and electricfurnace. This is performed by adding coke or coal from the top ofreaction shaft. This kind of gradient oxygen distribution would be helpfulfor reducing Fe₃O₄ content and intensifying smelting. The optimizedoperation of controlling Fe₃O₄ formation is obtained with the numericalsimulation of the copper flash smelter.At the end, the structure of super-intensified concentrate burner isstudied and designed conceptually. It’s a kind of swirl nozzle, which canchange the flame shape and the reaction process with different swirlingnumber. With the super-intensified concentrate burner, the highest throughput will be 3～4 times as before. With a series of simulation test, itis proved that feeding the concentration with air and optimizing the mainoperation parameters would successfully realize the ideas and aim of thedesign for the burner.更多还原