摘要
基于TG-DTA同步热分析技术,对棉秆成型前后不同粒径下的热解特性进行研究。结果表明:成型过程可以使棉秆的组织结构发生变化,热稳定性增强。粒径较小(>20目)时,其热解特性受本征化学反应和外扩散为主的传热作用的控制;当粒径进一步增大时,内热阻的影响作用随之增大。利用Li Chung-Hsiung积分法拟合成型颗粒在等速升温热解过程中的单方程宏观动力学模型对比分析不同粒径下的活化能E和指前因子A的变化规律,为棉秆成型颗粒燃料的热解技术应用提供相应理论模型。
The pyrolysis behavior of cotton stalk and their briquette was studied in different particle size at the heating rates of 20 ℃/min by thermogravimetric analysis （TG） coupled with differential thermal analysis （DTA） technique. The results indicated that forming process could enhance the thermal stability of the cotton stalk. When particle size is smaller than 20 mesh, the pyrolysis behavior of big sample cotton stalk is controlled by intrinsic chemical reaction and diffusion of the heat transfer; when particle size increases further, the influence of internal heat resistance becomes more important. A proper pyrolysis mechanism model was proposed based on Li Chung-Hsiung integral method. It shows that the activation energy （E） and pre-exponential factor （A） varies from different particle size, and they can provide more pertinent theoretical model for the pyrolysis technology of biomass briquette fuel.
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2016年第5期1308-1314,共7页
Acta Energiae Solaris Sinica
基金
国家科技支撑计划(2012BAD30B01)
中央高校基本科研业务费专项资金(2013HGBH0034)
关键词
生物质
成型颗粒
热解
热重分析
粒径
动力学
biomass
briquette
pyrolysis
thermogravimetric analysis
particle size
kinetics
