麦秆的热解特性研究及其动力学分析  

Study on Pyrolysis Characteristics and Kinetics of Wheat Straw

作　　者：肖卓炳[1] 郭瑞轲[1] 郭满满[1] 

机构地区：[1]吉首大学林产化工工程湖南省重点实验室,湖南张家界427000

出　　处：《化学世界》2013年第12期705-709,共5页Chemical World

基　　金：湖南省高校科技创新团队支持计划(湘教通(2010)212);湖南省科技厅项目(2012TP4020-2);校级科技项目研究生资助项目(13JDY057)

摘　　要：对小麦秸秆在实验条件下研究了热解过程的影响,并对其进行了动力学分析。样品粒径分别为0～0.1mm、0.1～0.25mm、0.25～1mm、1～2mm,实验过程升温速率分别为5℃/min、10℃/min、15℃/min、20℃/min,升温区间为25～700℃,采用氮气作为实验保护气。结果表明:热解最佳粒径为0.1～0.25mm;最佳升温速率为10℃/min;小麦秸秆热解活化能在120～170kJ/mol之间;提出了小麦秸秆热解的机理函数,积分形式机理函数为g(α)=[1-(1-α)1/3]2,微分形式机理函数为f(α)=1.5(1-α)2/3[1-(1-α)1/3]-1,反应级数n=2;热解活化能和指前因子随着转化率的增加,先降后升,在转化率为0.5时有最小值。The effect of experimental conditions on pyrolysis process of wheat straw and its kinetics were studied. The sample sizes were0.1 ram, 0.1 - 0.25mm, 0.25 -1mmand1- 2mm; the experimental heating rates were 5 ℃/min, 10 ℃/min, 15 ℃/min and 20 ℃/mint and the range of heating was 25 to 700 ℃ under nitrogen atmosphere. The experimental results showed that the best particle size for pyrolysis was 0.1 -0.25 mm; optimum heating rate was 10 ℃/min; and the activation energy of pyrolysis was be- tween 120 and 170 kJ/mol. The mechanism function of pyrolysis for wheat straw was proposed. The inte- gral and differential mechanism functions were g（a） = [1- （1-a）1/3 ]2 and f（a）= 1.5 （1-a）2/3 [1-（1-a）1/3 ]1, and the reaction order n was 2. With the increase of the conversion rate, the activation energy and pre-ex- ponential factor were reduced at first and then increased and both had a minimum value at the conversion rate of 0. 5.

关 键 词：小 麦秸秆 实验条件 TG—DTG技术 热分解动力学 

分 类 号：TK62[动力工程及工程热物理—生物能]