燃煤烟气环境下臭氧脱除苯的反应机理及动力学  

Mechanism and Kinetic of the Reduction of Benzene by Ozone in Flue Gas

作　　者：温正城[1] 周俊虎[1] 王智化[1] 杨卫娟[1] 刘建忠[1] 岑可法[1] 

机构地区：[1]浙江大学能源清洁利用国家重点实验室,杭州310027

出　　处：《燃烧科学与技术》2008年第2期171-175,共5页Journal of Combustion Science and Technology

基　　金：国家自然科学基金(50476059);国家重点基础研究发展计划(973)资助项目(2006CB200303)

摘　　要：在构建反应机理的基础上,通过敏感性分析及动力学计算,确定了关键基元反应,并深入分析影响苯脱除效果的主要因素.结果表明,NO_3生成量是影响苯脱除效果的关键因素;臭氧与苯反应并不是关键基元反应,对苯的脱除几乎没有影响;脱除率随温度的升高和臭氧加入量的增大而增加;苯初始体积分数越低,脱除率越高,氧量的变化不会对脱除效果产生影响;在典型锅炉排烟气氛下,以体积分数为0.1×10^(-6)的苯为例,要有效地控制苯排放,O_3/NO物质的量的比R≥1.6,停留时间以1 s为宜,温度以250℃为宜,苯脱除效率可达65%以上.Based on the established chemical mechanism, sensitivity analysis and kinetic calculations were performed by CHEMKIN to affirm the important primitive reactions and the major factors affecting the reduction of benzene were deeply analyzed. Results indicate that the formation of NO3 is the most important factor affecting the reduction of benzene. The reaction between ozone and benzene is not an important elemental reaction with little effect on the reduction. The reduction improves with the rising of the temperature, the increasing of amount of added ozone and the descending of initial concentration of benzene. But the variation of O2 concentration will not affect the reduction. Under typical flue gas conditions, assuming that the initial concentration of benzene is 0.1 × 10^-6, to control benzene effectively, the factors should be as follows： R≥ 1.6, t = 1 s, T = 250 ℃, then the reduction will be above 65 %.

关 键 词：苯 臭氧 机理 动力学 烟气 脱除 

分 类 号：TK477[动力工程及工程热物理—动力机械及工程]