Kinetics of Poplar Short Rotation Coppice Obtained from Thermogravimetric and Drop Tube Furnace Experiments

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• 作者：Sandrina Pereira ; Paula C. R. Martins ; Mário Costa
• 刊名：Energy & Fuels
• 出版年：2016
• 出版时间：August 18, 2016
• 年：2016
• 卷：30
• 期：8
• 页码：6525-6536
• 全文大小：722K
• 年卷期：0
• ISSN：1520-5029

文摘

This article concentrates on the kinetics of poplar short rotation coppice obtained from thermogravimetric and drop tube furnace (DTF) experiments. Three poplar samples were studied, specifically, clone AF8 from two different plantations, one located in Italy (AF8-I) and another located in Portugal (AF8-P), and clone AF2 from a plantation located in Portugal. Initially, the combustion behavior of the three clones was evaluated by thermogravimetry. For the devolatilization zone, the thermogravimetric experiments yielded apparent activation energies of 109.7, 117.7, and 118.6 kJ mol^–1 for clones AF8-I, AF8-P, and AF2, respectively. For the char oxidation stage, the apparent activation energies were 267.4, 252.0, and 264.3 kJ mol^–1 for clones AF8-I, AF8-P, and AF2, respectively. Subsequently, the combustion behavior of the clone AF8-I was examined in a DTF. The data reported includes gas temperature and particle burnout measured along the DTF for five wall temperatures (900, 950, 1000, 1050, and 1100 °C). The kinetic parameters based on the DTF data were calculated using two models: a model-fitting approach and a model proposed by Ballester and Jiménez. In the devolatilization zone, the apparent activation energies vary from 34.1 kJ mol^–1 for the former model to 12.8 kJ mol^–1 for the latter model, whereas, in the char oxidation zone, both models originate similar apparent activation energies (73.2 and 69.0 kJ mol^–1). While the combustion process in the thermogravimetric experiments is controlled by kinetics, in the DTF experiments, the diffusion effects also limit the process, according with the DTF temperature.