煤燃烧还原区NO/氧存在下armchair型焦炭N的迁移转化特性  

N Migration and Transformation Characteristics of Armchair Char-N in the Presence of NO/Oxygen in the Reduction Zone of Coal Combustion

作　　者：陈萍 高卫 顾明言 Chen Ping;Gao Wei;Gu Mingyan(School of Energy and Environment,Anhui University of Technology,Ma’anshan 243002,China)

机构地区：[1]安徽工业大学能源与环境学院,马鞍山243002

出　　处：《燃烧科学与技术》2022年第4期389-396,共8页Journal of Combustion Science and Technology

基　　金：国家重点基础研发计划资助项目(2017YFB0601805);安徽工业大学校青年基金资助项目(QZ202017).

摘　　要：采用量子化学方法分析煤燃烧还原区高浓度NO条件下armchair型焦炭N的析出机理,并通过构建含羟基armchair型焦炭N模型,从微观层面对氧存在下焦炭N的迁移转化特性进行了系统的理论计算.结果表明,氧促进了焦炭N的析出.氧和NO的存在改变了焦炭N的迁移转化特性,表现为将C氧化成CO的同时,NO与焦炭中N结合为N_(2)或N_(2)O释放.NO与含羟基armchair型焦炭N结合为N_(2)O的决速步能垒值较转化为N_(2)的高130.35 kJ/mol,表明NO与焦炭中的N结合成N_(2)的过程较将N氧化成N_(2)O的过程更容易进行.The quantum chemistry method is used to analyze the precipitation mechanism of armchair char-N un-der the condition of high concentration of NO in the reduction zone of coal combustion.The migration and transformation characteristics of char-N in the presence of oxygen are systematically calculated at the micro level by constructing the char-N model containing a hydroxyl group.Results show that oxygen promotes the precipitation of char N.The presence of oxygen and NO changes the migration and transformation characteristics of char-N,which is manifested as the oxidation of C to CO and the release of NO combined with N in the char to form N_(2)or N_(2)O.The energy barrier value of the rate-determining step for NO combining with N in hydroxyl-containing armchair char to form N_(2)O is 130.35 kJ/mol higher than that for conversion to N_(2),indicating that the process of NO combining with N in the char to form N_(2)is easier than that of N oxidation to N_(2)O.

关 键 词：焦炭N 迁移转化 NO 羟基 

分 类 号：TK16[动力工程及工程热物理—热能工程]