A novel insight into biomass pyrolysis - The process analysis by identifying timescales of heat diffusion, heating rate and reaction rate
A novel insight into biomass pyrolysis - The process analysis by identifying timescales of heat diffusion, heating rate and reaction rate
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DOI：
10.1016/j.energy.2019.116159
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发表时间：
2019-12-15
期刊：
影响因子：
9
通讯作者：
Wardach-Swiecicka, Izabela
中科院分区：
文献类型：
--
作者：
Kardas, Dariusz;Hercel, Paulina;Wardach-Swiecicka, Izabela
热解过程涉及物理和化学耦合子过程的复杂性是其深入认识的瓶颈。这也是由于物理化学参数似乎没有充分确定，特别是对于生物质。这项研究的动机是木材热解过程描述的不一致性，主要是指反应动力学方面的不确定性。探讨了一种分析生物质脱挥发过程的新方法。重点强调了热传递过程的关键作用及其对单个样品热解动力学的影响。考虑了相互影响的特征时间尺度，即加热速率、传热速率和反应速率。理论研究采用简单的双方程模型。采用了标准的传热方程和质量守恒方程，方法略有不同。在0.49 ~ 15.4 mm的样品中，在不同的反应速率下，得到了极低加热速率（1.7 K/min）和高加热速率（170 K/min）下的质量损失曲线和温度分布。根据计算结果，概述了过程时间尺度在热解动力学分析中的可能作用。(C) 2019作者。Elsevier Ltd.出版。
The complex nature of pyrolysis that involves coupled physical and chemical sub-processes is a bottleneck for its in-depth recognition. This is also due to physical-chemical parameters, which appear insufficiently identified, particularly for biomass. This study is motivated by the inconsistencies in the description of wood pyrolysis processes and primarily refers to the uncertainties in terms of kinetics of reaction. A new approach to analyze the biomass devolatilization was discussed. A strong emphasis was placed on the crucial role of thermal transport processes and their impact on the kinetics of pyrolysis of a single sample. Characteristic timescales influencing each other, namely: heating rate, heat transfer and reaction rates, were considered. The theoretical research was conducted with a use of a simple two-equation model. A standard heat transfer equation for the sample and a mass conservation equation with slightly different approach were implemented. Mass loss curves and temperature profiles were presented for very low heating rate (1.7 K/min) and high heating rate (170 K/min) for samples of size ranging from 0.49 mm to 15.4 mm, while assuming different reaction rates. Based on the calculation results, the possible role of the process timescales in analysing the kinetics of pyrolysis was outlined. (C) 2019 The Authors. Published by Elsevier Ltd.