木材热解过程中颗粒内部传热模型的探析  

Investigation of the heat transfer model in a single wood particle during the pyrolysis process

作　　者：景亮晶[1] 李瑞[1] 邓旭升[1] 何亮[1] 吕兆琳[1] 

机构地区：[1]北京林业大学材料科学与技术学院,北京100083

出　　处：《可再生能源》2011年第6期81-85,共5页Renewable Energy Resources

基　　金：中央高校基本科研业务费专项资金(JD2010-3)

摘　　要：木材快速热解液化是农林生物质热化学利用的手段之一。木材颗粒内部的传热控制其快速热解反应,是快速热解工艺优化研究的关键。文中建立了一个二维圆柱体的非稳态传热模型,对木材热解过程中颗粒内部传热进行模拟,并且充分考虑了木材颗粒的各向异性和热解过程中木材热物理性质随温度的变化以及热解过程中反应热、含水率等因素;采用有限元的计算方法进行求解计算。研究结果表明:木材颗粒热解过程中,热量由外向内传递,热解反应由外向内分层递进;含水率会对木材的热解速率产生显著影响,水分的存在会阻碍热量由外向内传递;木材的热物理性质随温度的变化及木材的各向异性在模拟计算过程中不可忽略。Wood fast pyrolysis technology is one of most promising methods to utilize biomass resources. Heat transfer in wood particle is the key to optimize wood pyrolysis process for controlling the pyrolysis process. A 2-D transient heat transfer model was made in cylindrical to predict the thermal behavior in a single wood particle during the pyrolysis process. Wood anisotropy and thermophysical properties were considered in the model, as well as the influence of heat generation and moisture content on temperature distribution in wood particle. The FEM was used to solve the heat transfer equation. It showed that the heat transfer was from outside to inside in a single wood particle during pyrolysis process, and moisture content had a obvious influence to the pyrolysis reaction.The existence of moisture content could hinder the thermal transfer from outside to inside. In addition, Wood anisotropy and thermophysical properties should be considered both when modeling the heat transfer in a single wood particle during the pyrolysis process.

关 键 词：传热 热解 颗粒 木材 

分 类 号：TK6[动力工程及工程热物理—生物能] S216.2[农业科学—农业机械化工程]