热解过程中生物质半焦比热容的测定  

Determination of specific heat capacity of biomass char during pyrolysis

作　　者：陈群[1] 庞任重 陈熙[1] 杨锐明[1] 禚玉群[1] 陈昌和[1] 

机构地区：[1]清华大学热能工程系热科学与动力工程教育部重点实验室盐碱地区生态修复与固碳研究中心,北京100084

出　　处：《燃料化学学报》2014年第9期1040-1046,共7页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(51276099);清华大学自主科研计划(2011Z02147)

摘　　要：采用热重-差示量热扫描法（TG-DSC）测量了生物质和一次热解焦炭及不同转化率下半焦的比热容，建立了计算半焦比热容的数学模型并与实验测量结果进行了对比。结果表明，生物质样品和热解焦炭的比热容在60～200℃随温度升高而线性增大。生物质焦炭的比热容低于生物质样品的比热容，从60℃时的1．2J/（g·K）增大到200℃附近的1．8～2．0J/（g·K）。生物质半焦比热容随热解转化率的提高而降低。由半焦比热容数学模型计算得到的结果在接近150～200℃时与实验测定的半焦比热容数值基本一致。The specific heat capacities of chars during primary pyrolysis of biomass with different conversion and the heat capacities of virgin biomass were determined.The ratio method was employed to measure the specific heat capacities of two biomass samples and their pyrolyzed chars through thermogravimetry and differential scanning calorimetry （ TG-DSC）.A mathematical model was developed to calculate values of specific heat of chars.The results show that the specific heat capacitei s of the two biomass samples and their derived chars increase linearly within 60-200℃.The values oft he specific heat capacity fo the chars are lower than those fo the virgin biomass samples.The specific heat of chars decreases as the extent of pyrolysis increases.The calculated specific heat capacities from the developed mathematical model are quite close to those me asured by TG-DSC analyses eb twe n 150-200℃.

关 键 词：生物质 热解 焦炭 比热容 热分析 

分 类 号：TK6[动力工程及工程热物理—生物能]