基于FWO法与CR法的中蒙边境森林草原交错区沟塘草甸羊草热解动力学分析  

Pyrolysis kinetics analysis of Leymus chinensis in swamp meadow in forest-steppe ecotone of China-Mongolia border based on FWO and CR methods

作　　者：王玉霞[1] 张彤 张恒[1] WANG Yu-xia;ZHANG Tong;ZHANG Heng(College of Forestry,Inner Mongolia Agricultural University,Inner Mongolia Hohhot 010019,China)

机构地区：[1]内蒙古农业大学林学院,内蒙古呼和浩特010019

出　　处：《消防科学与技术》2021年第11期1666-1670,共5页Fire Science and Technology

基　　金：国家自然科学基金项目(31860211)。

摘　　要：以内蒙古自治区阿尔山市内沟塘草甸为研究区域,选取典型草本羊草为研究对象,运用热重分析法以通氧速率10、20、30 mL/min,在升温速率分别为40、80℃/min的条件下进行热失重行为研究。使用TG-DTG曲线分析样品的热解过程,利用Coats-Redfern(CR)积分法和Flynn-Wall-Ozawa(FWO)积分法对样品的快速热解阶段进行动力学分析,得出在不同氧气浓度下样品的热解活化能和指前因子并求得相应参数。结果表明羊草热解过程分为:失水阶段、快速热解阶段、炭化阶段。其中快速热解阶段为350~450℃,此阶段中升温速率越快,温度滞后现象越明显;通氧速率越快,温度超前现象越明显。热解过程及动力学参数分析表明,Flynn-Wall-Ozawa法更适用于羊草热解过程,引发火灾危险程度的通氧速率为:30 mL/min>20 mL/min>10 mL/min。Swamp meadow in Aershan city,Inner Mongolia Autonomous Region was taken as the research area,the typical herbaceous Leymuschinensis was taken as the research object,and the thermogravimetric analysis was used to study the thermogravimetric behavior under the conditions of oxygen flow rate of 10,20,30 mL/min and heating rate of 40,80℃/min,respectively.TG-DTG curve were used to analyze the pyrolysis process of the sample,and Coats-Redfern(CR)integration method and Flynn-Wall-Ozawa(FWO)integration method were used to analyze the kinetics of the rapid pyrolysis stage of the sample to obtain the pyrolysis activation energy,pre-exponential factor and corresponding parameters of the sample under different oxygen concentrations.The results showed that the pyrolysis process of Leymus chinensis can be divided into three stages:dehydration stage,rapid pyrolysis stage and carbonization stage,in which the rapid pyrolysis stage is 350~450℃.In this stage,the faster the heating rate is,the more obvious the temperature lag is;the faster the oxygen flow rate is,the more obvious the temperature advance is.The analysis of pyrolysis process and kinetic parameters showed that FWO method is more suitable for the pyrolysis process of Leymus chinensis,and the oxygen flow rate that causes fires is 30 mL/min>20 mL/min>10 mL/min.

关 键 词：热重分析 热解特性 沟塘草甸 羊草 森林火灾 中蒙边境 

分 类 号：X954[环境科学与工程—安全科学] S762.3[农业科学—森林保护学]