The torrefaction of three representative types of biomass—bamboo, and Douglas fir and its bark—was carried out in a cylindrical-shaped packed bed reactor under nitrogen flow at 573 K of the reactor wall temperature. As the thermal energy for the torrefaction was supplied from the top and the side of the bed, the propagation of the temperature profile of the bed is a crucial factor for discussing and improving the torrefaction reactor performance. Therefore, the temperature and gas flow rate (vector) profiles throughout the bed were calculated by model simulation so as to scrutinize this point. The measured temperature at a certain representative location (z = 30 mm and r = 38 mm) of the bed was well reproduced by the simulation. The volume faction of the bed at temperatures higher than 500 K at 75 min was 0.89, 0.85, and 0.99 for bamboo, and Douglas fir and its bark, respectively. It was found that the effective thermal conductivity is the determining factor for this difference. The heat of the reactions was found to be insignificant.

中文翻译：

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木质纤维素生物质烘焙过程中的传热和传质：纤维素，半纤维素和木质素等主要成分的贡献

在圆柱形填充床反应器中，在反应器壁温度为573 K的氮气流下，对三种代表性生物质（竹，花旗松及其树皮）进行了焙干。由于用于焙干的热能是从床的顶部和侧面提供的，所以床的温度分布的传播是讨论和改善焙干反应器性能的关键因素。因此，通过模型模拟计算了整个床层的温度和气体流速（矢量）曲线，以便对这一点进行详细研究。在某个代表性位置（z = 30 mm和r通过模拟可以很好地再现床的直径（= 38 mm）。在75分钟内，温度高于500 K时，竹子和花旗松及其树皮的床体积分率分别为0.89、0.85和0.99。发现有效导热率是造成这种差异的决定因素。发现反应的热量微不足道。