摘要
以稻杆为原料考察了不同温度和含氧量下生物质的低温烘焙过程,研究了有氧烘焙的机理。对含氧气氛下不同停留温度时的质量残留率和微分热重分析(DTG)曲线进行分析发现,停留温度对质量残留率影响较大,是烘焙过程的主导因素。对6个不同含氧量下的质量残留率和DTG曲线分析可知,氧气加快了反应的进行,且随着含氧量上升发生分解的组分有所增加。建立了6个含氧量下稻杆低温烘焙的动力学模型并计算了动力学参数,发现稻杆表观活化能在1.33 k J/mol到2.01 k J/mol之间,且氧浓度与活化能的线性拟合度较好。
Torrefaction is a well-established thermo-chemical method to enhance the energy density of biomass through the variation of reaction temperature and atmosphere. Oxygen-involved torrefaction, defined as oxidative torrefaction, has attracted more and more attentions, by virtue of its short torrefaction stage and self-heating process. In this work, the isothermal torrefaction process of rice straw at different temperatures and oxygen concen- trations was investigated by means of thermo gravimetric analysis （TGA）. It was found that mass yield decreased with increasing temperature. Oxygen has a positive effect on the rate of torrefaction, while the extent of decomposi- tion decreased with increasing oxygen concentration. The separate-stage kinetic model was adopted to describe the oxidative torrefaction of biomass. The apparent activation energy for the torrefaction of rice straw was between 1.33 kJ/mol and 2.01 kJ/mol, and varied linearly with oxygen concentration.
作者
张岚清
沈德魁
ZHANG LanQing SHEN DeKui(Key Laboratory of Energy Thermal Conversation and Control of Ministry of Education,School of Energy and Environment Southeast University, Nanjing 210096, China)
出处
《北京化工大学学报（自然科学版）》
CAS
CSCD
北大核心
2017年第5期27-32,共6页
Journal of Beijing University of Chemical Technology(Natural Science Edition)
基金
国家自然科学基金(51476934)
关键词
稻杆
低温烘焙
含氧气氛
热重分析
恒温动力学
rice straw
torrefaction
oxygen-containing atmosphere
thermo gravimetric analysis （TGA）
isother-mal kinetics
