低次烟叶热解特性及动力学机理函数  

Characteristics and Kinetics Mechanism Function of Pyrolysis of Low-Grade Tobacco

作　　者：陆炳祥 张德祥[1] LU Bingxiang;ZHANG Dexiang(Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education,Department of Chemical Engineering for Energy Resources,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学能源化工系煤气化及能源化工教育部重点实验室

出　　处：《华东理工大学学报（自然科学版）》2019年第5期711-718,共8页Journal of East China University of Science and Technology

基　　金：国家重点基础研究发展计划(973)项目(2011CB201304)

摘　　要：采用固定床管式反应器,考察了热解温度对低次烟叶热解产物产率、组成的影响。利用热重分析仪,在不同的升温速率下对低次烟叶的热失重行为进行了研究,运用Coats-Redfern积分法、Flynn-Wall-Ozawa(FWO)积分法,结合双外推法确定其动力学机理函数。实验结果表明:随温度升高,热解油产率先增大,在400℃达到最大,为26.93%,然后开始下降;热解气产率不断增大;焦炭产率不断下降。热解油主要由酮类、酚类、呋喃类和含氮杂环化合物组成,热解气主要由CO、CO2组成。低次烟叶的热解过程可以分为脱水干燥、快速热解和炭化3个阶段。主要热解区间第1段(T0~Tmax)的最概然机理函数为D3(Jander方程),第2段(Tmax^Tf)最可能的机理函数为D4(G-B方程)。Biomass is considered to be a promising renewable energy source and has attracted increasing attentions from researchers.Biomass pyrolysis is a promising thermochemical conversion technology,which can generate pyrolysis oil,bio-char and pyrolysis gas.In this paper,the effects of pyrolysis temperature on the yield and composition of low-grade tobacco pyrolysis products were investigated on the basis of a fixed-bed tubular reactor.The weight loss behavior of low-grade tobacco was studied by thermogravimetric analyzer at different heating rates.The kinetics mechanism function was determined by Coats-Redfern and FWO integral method combined with double extrapolation method.The results showed that the yield of pyrolysis oil underwent an initial increase with increasing the temperature, reaching the maximum value of 26.93% at 400 ℃.Further increase in temperature led to a decrease in the yield of pyrolysis,a increase in the yield of pyrolysis gas,and continuous decrease in the yield of bio-char.Pyrolysis oil is mainly composed of ketones,phenols,furans and nitrogen-containing heterocycles compounds.Pyrolysis gas is mainly composed of CO and CO2.The pyrolysis process of low-grade tobacco can be divided into three stages:dehydration and drying stage;rapid pyrolysis stage;and carbonization stage.The main stage of pyrolysis can be divided into two sub-stages,the most probable mechanism function of the first sub-stage (T0-Tmax) is D3 (Jander equation),while the most probable mechanism function of the second sub-stage (Tmax-Tf) is D4 (G-B equation).

关 键 词：低次烟叶 热解 双外推法 机理函数 

分 类 号：TK6[动力工程及工程热物理—生物能]