冶金尘泥含碳球团直接还原机制的试验研究  

Experimental study on mechanism of direct reduction of metallurgical dust carbon-containing pellets

作　　者：何环宇 刘虹灵 崔一芳[1,2,3] 李杨 丁娟[1,2,3] HE Huanyu;LIU Hongling;CUI Yifang;LI Yang;DING Juan(The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Hubei Provincial Engineering Technology Research Center of Metallurgical Secondary Resources,Wuhan 430081,Hubei,China)

机构地区：[1]武汉科技大学省部共建耐火材料与冶金国家重点实验室,湖北武汉430081 [2]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,湖北武汉430081 [3]湖北省冶金二次资源工程技术研究中心,湖北武汉430081

出　　处：《钢铁研究学报》2021年第3期196-201,共6页Journal of Iron and Steel Research

基　　金：国家自然科学基金资助项目(51604202);武汉科技大学省部共建耐火材料与冶金国家重点实验室青年基金资助项目(2016QN09)。

摘　　要：以气固反应相继发生动力学模型为基础开展冶金尘泥含碳球团直接还原试验,考察还原速率、还原率以及还原气氛等表征还原特性的特征参数在整个还原过程的变化,研究冶金尘泥含碳球团的还原行为及过程的作用机制。结果表明:冶金尘泥含碳球团的还原过程由孕育启动期、快速反应期和反应结束期组成,反应进程快,3~5 min就能达到碳气化和铁氧化物还原剧烈进行的温度。在1270℃以下,升高温度对含碳球团还原有明显加速作用,但进一步提高温度,球团n(C)/n(O)((C、O摩尔比))及球团中碳的消耗对还原过程的影响更为显著,表现在最大还原速率维持时间延长,还原率大幅提高。碳气化反应是含碳球团还原过程最重要的环节,其反应生成的CO决定了铁氧化物还原反应物的供给速度。反应过程处于明显的还原性气氛中,气氛中CO_(2)来自于部分CO的进一步氧化,其含量多少取决于气氛中CO的数量和反应的进程。Based on gas-solid reaction kinetics model,direct reduction process of metallurgical dust carbon-containing pellets were studied.The characteristic parameters of reduction rate,reduction degree and reduction atmosphere that characterize the reduction characteristics were investigated systematically.The results show the reduction behavior and mechanism of metallurgical dust carbon-containing pellets in the reaction process were illustrated clearly.Reduction process of metallurgical dust carbon-containing pellets can be divided into three steps:start-up stage,rapid response and the response end period.The reaction process is fast,and the temperature for carbon gasification and iron oxide reduction can be reached in 3-5 minutes.Under 1270℃,the reduction content of the carbon-containing pellets is increased with the increasing of temperature.However,with the further increase of temperature,n(C)/n(O) and the consumption of carbon in pellets have a more significant impact on the reduction process,which is reflected in the prolonged maintenance time of the maximum reduction rate and the greatly increased reduction degree.Carbon gasification is the most important part of the reduction process of carbon containing pellets,because the produced CO determines the reduction rate of pellets.The reaction process is in an obvious reducing atmosphere.The CO_(2) in the atmosphere comes from the further oxidation of part of CO,and its content depends on the amount of CO in the atmosphere and the progress of the reaction.

关 键 词：冶金尘泥 含碳球团 直接还原过程 相继发生模型 还原机制 

分 类 号：TF533[冶金工程—钢铁冶金]