干熄焦除尘灰作还原剂直接还原低品位褐铁矿机理分析  

Analysis on the Mechanism of Direct Reduction of Limonite by Coke Quenching Ash as Reducing Agent

作　　者：陈伟鹏[1] 王强 冯志明 陈晓丹 赵增武[1] 武文斐[1] 李保卫 Chen Weipeng, Wang Qiang, Feng Zhiming, Chen Xiaodan, Zhao Zengwu, Wu Wenfei, Li Baowei(School of Energy and Environment,Inner Mongolia University of Science and Technology,Baotou 014010,Inner Mongolia ,Chin)

机构地区：[1]内蒙古科技大学能源与环境学院

出　　处：《钢铁钒钛》2018年第1期78-83,共6页Iron Steel Vanadium Titanium

基　　金：内蒙古自治区应用技术研究与开发基金资助项目(编号:20130310);内蒙古自治区创新团队计划资助项目(编号:NMGIRT1406)

摘　　要：以干熄焦除尘灰为新型还原剂，在温度20～1 100 ℃，通过热分析仪揭示其与低品位褐铁矿粉末在不同配碳比下升温过程中的反应机理。研究了不同配碳比对反应速率的影响，试验结果表明：适当过量的碳会加速氧化还原的进行。反应体系在升温过程中进行的是固—固反应和气—固反应的二步反应机理，并且635.2 ℃是碳还原作用开始温度，而温度高于919.5 ℃时，铁氧化物的还原主要是借助CO的直接还原，并且碳的气化速度与温度关系十分敏感，是整个还原反应的控制性环节。试验结束后对配碳比为1.2的还原产物通过扫描电子显微镜（SEM）进行微观行貌分析，发现还原产物铁均匀析出且渣铁相界分明。通过X射线衍射（XRD）进行物相检测，发现还原产物中无铁氧化物衍射峰，并且铁金属衍射峰明显。The reaction mechanism of low-grade limonite powder in the process of heating with different carbon-oxygen ratio was revealed by thermal analysis at temperature of 20 - 1 100℃ ,using coke quenching ash as a new reducing agent. The effects of different carbon ratios on the reaction rate were studied. The ex- perimental results showed that proper excess carbon accelerates the redox. The reaction system was out in the two-step reaction mechanism of solid-solid reaction and gas-solid reaction during the carried heating process, the speed of carbon gasification is very sensitive to temperature, and is the controlling link of the whole reduction reaction. And 635.2℃ is the initial carbon reduction temperature,while the temperature is higher than 919.5℃,the reduction of iron oxide mainly by direct reduction of CO. After the end of the ex- periment, the reduction products with carbon-oxygen ratio of 1.2 was analyzed by scanning electron micros- copy （ SEM）, and It was found that the iron of the reduction product was evenly dispersed, and the iron slag phase boundary was distinct. Through X-ray diffraction （XRD）, it was found that no iron oxide diffraction peak was found in the reduction products, and the iron metal diffraction peak was obviously.

关 键 词：低品位褐铁矿 直接还原 干熄焦除尘灰 配碳比 反应机理 热重分析 

分 类 号：TF55[冶金工程—钢铁冶金] X784[环境科学与工程—环境工程]