In situ observation of the evolution of polyaromatic tar precursors in packed-bed biomass pyrolysis
In situ observation of the evolution of polyaromatic tar precursors in packed-bed biomass pyrolysis
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填充床生物质热解中聚芳焦油前体演化的原位观察
DOI：
10.1039/d1re00032b
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发表时间：
2021
影响因子：
3.9
通讯作者：
Chelang'at Mosonik M
中科院分区：
文献类型：
--
作者：
Chelang'at Mosonik M
热解为木质纤维素生物质转化为固体、液体和气体能量载体或平台化学品提供了途径。在生物质热解反应的气相中产生的多环芳烃（PAH）可能冷凝形成焦油，焦油难以进一步升级并导致工艺效率低下。焦油生产的控制需要优化反应器的设计和仔细控制反应器的操作条件。在本研究中，一个垂直的连续加热的固定床反应器被用来研究热解峰值温度和保持时间（在峰值温度）的两个木质纤维素生物质样品，核桃壳（WS）和杏仁壳（AS）热解过程中的多环芳烃的形成的影响。“原位”平面激光诱导荧光（PLIF）是用来光学检测3至5环多环芳烃的气相反应器床层上方。结果表明，生物质样品的PAH PLIF信号出现在275 °C，WS和AS的峰值分别出现在400 °C和375 °C，这与作者之前进行的“离地”分析一致。超过400 °C，观察到PLIF信号显著降低，并且在550 °C时几乎消失。初始PAH的形成归因于由于温度沿着样品床下降而发生的缩合反应。PAH PLIF信号本身及其变化强度的检测，靠近床，标志着从生物质释放的产品经历的快速变化，并强调了使用在线技术进行热解研究的重要性。从这项研究中对PAH形成的温度依赖性特征的详细了解可以帮助改进反应器设计。
Pyrolysis provides a route for the conversion of lignocellulosic biomass into solid, liquid and gaseous energy vectors or platform chemicals. Polycyclic aromatic hydrocarbons (PAHs) generated in the vapour phase of the biomass pyrolytic reaction may condense to form tars, which are difficult to further upgrade and cause process inefficiency. Control of tar production requires optimization of reactor design and careful control of reactor operating conditions. In this study, a vertical resistively-heated fixed-bed reactor is used to study the effect of pyrolysis peak temperatures and holding period (at peak temperature) on the formation of PAHs during pyrolysis of two lignocellulosic biomass samples, walnut shells (WS) and almond shells (AS). ‘In situ’ planar laser induced fluorescence (PLIF) is used to optically detect 3-to-5 ring PAHs in the vapour phase immediately above the reactor bed. Results show that the PAH PLIF signal appeared at ∼275 °C for the biomass samples and peaked at ∼400 °C for WS and ∼375 °C for AS, which is in agreement with previous ‘off situ’ analysis conducted by the authors. Beyond 400 °C, the PLIF signal was observed to reduce significantly and almost disappear at 550 °C. Initial PAH formation was attributed to condensation reactions occurring due to the drop in temperature along the sample bed. The detection of the PAH PLIF signal itself and its changing intensities, close to the bed, signified the rapid changes the products released from biomass undergo and emphasised the importance of using online techniques for pyrolysis studies. The detailed understanding of the temperature dependent characteristics of PAH formation from this study could help improve reactor design.
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欧洲供热和发电用木屑颗粒的国际物流：意大利、瑞典和荷兰颗粒消耗的成本、能源输入和温室气体平衡
DOI：
--
发表时间：
2010
期刊：
影响因子：
--
作者：
R. Sikkema;M. Junginger;W. Pichler;S. Hayes;A. Faaij
通讯作者：
A. Faaij
影响因子：
3.5
作者：
C. Brackmann;M. Aldén;P. Bengtsson;K. Davidsson;J. Pettersson
通讯作者：
J. Pettersson
应用激光诱导荧光 (LIF) 对技术规模固定床反应器中木颗粒热解的焦油进行在线表征
DOI：
--
发表时间：
2013
期刊：
影响因子：
--
作者：
A. Dieguez;A. Anca;N. Zobel
通讯作者：
N. Zobel
影响因子：
11.4
作者：
Carrier, Marion;Joubert, Jan-Erns;Knoetze, Johannes (Hansie)
通讯作者：
Knoetze, Johannes (Hansie)
影响因子：
6
作者：
N. Zobel;A. Anca-Couce
通讯作者：
N. Zobel;A. Anca-Couce