铁矿石载氧体甲烷还原热重动力学分析  

Research on Methane Reduction Kinetics of Iron Ore Oxygen Carrier Based on TGA

作　　者：张怿[1] 金保昇[1] 王晓佳[1] 刘先立[1] 刘溪[1] 

机构地区：[1]能源热转换及其过程测控教育部重点实验室(东南大学),南京市210096

出　　处：《电力建设》2013年第6期7-10,共4页Electric Power Construction

基　　金：国家自然科学基金资助项目(51076029);国际科技合作项目(2010DFA61960)

摘　　要：介绍了一种能够同时实现高效率发电和低能耗分离CO_2的新颖电站锅炉燃烧方式—化学链燃烧(chemicalloopingcombustion,CLS),并基于徐州利国铁矿矿石制备铁基载氧体,以CH_4为还原性气体进行了热重实验(thermogravimetric analysis,TGA),并针对TGA曲线数据进行了化学动力学分析。分析结果表明,温度是影响载氧体还原程度的重要因素,温度升高导致还原速率加快、还原程度加深。还原反应过程在450～700℃温度段由扩散控制的Valensi方程模型控制,而在850～1050℃温度段则由收缩球体模型控制,并依据模型分别计算出了相应模型的活化能和频率因子,为CLC应用于电力生产领域提供了理论指导。A novel combustion method used in boiler chemical-looping combustion （CLC） is introduced, which can simultaneously realize high-efficiency power generation and low-energy CO2 separation. Thermogravimetric analysis （TGA） was carried out in methane atmosphere, with iron ore from Xuzhou Liguo Iron Mine as the oxygen carrier, as well as the chemical kinetics was analyzed based on TGA curves. The results show that temperature is the key factor to the reduction of iron-based oxygen carrier, in which the reduction rate becomes faster and the reduction degree becomes deeper with the increase of temperature. ＇ In addition, the Valensi model between 450 - 700℃ and the contractive sphere model between 850 -1 050℃ are most suitable for the reduction of the iron-based oxygen carder, and the kinetic parameters including activation energy and pre-exponential factor are calculated according to the kinetic model respectively. The research results can provide theoretical guidance for CLC applied in electric power industry.

关 键 词：分离CO2 载氧体 化学链燃烧(CLC) 热重分析(TGA) 指前因子 活化能 

分 类 号：X701[环境科学与工程—环境工程] TQ028[化学工程]