The synergistic effect during co-combustion of municipal sludge and coal: Experimental and ReaxFF molecular dynamic study
The synergistic effect during co-combustion of municipal sludge and coal: Experimental and ReaxFF molecular dynamic study
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DOI：
10.1016/j.energy.2022.125553
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发表时间：
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期刊：
影响因子：
9
通讯作者：
Tong Xu;Chunbo Wang;Dikun Hong;Song-Geng Li;S. Yue
中科院分区：
文献类型：
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作者：
Tong Xu;Chunbo Wang;Dikun Hong;Song-Geng Li;S. Yue
在这项工作中，通过实验和ReaxFF分子动力学模拟研究了城市污泥/煤混燃的行为。基于实验表征构建了煤和污泥的分子模型。 ReaxFF MD模拟得到的污泥和煤分别燃烧的特性与恒温热重实验结果一致。通过在不同条件下进行污泥/煤共燃模拟，研究了对共燃特性的协同效应。结果表明，污泥/煤混燃对燃烧速率、O2消耗量、CO2产率等混燃特性具有积极的协同作用。利用原子标记方法发现，混燃过程中污泥的燃烧受到抑制，煤的燃烧得到促进。人们发现含碳气体是产生二氧化碳的重要中间产物。这种协同效应促进了煤的燃烧，因为污泥产生的一些·OH自由基攻击煤中的芳环结构，加速了污泥/煤共燃过程中碳质气体的形成。这项工作为城市污泥/煤混合燃烧的行为提供了新的见解。
In this work, the behaviors of municipal sludge/coal co-combustion were investigated by experiments and ReaxFF molecular dynamic simulations. The molecular models of coal and sludge were constructed based on experimental characterization. The characteristics of the separately combustion of sludge and coal from ReaxFF MD simulations were consistent with that from thermostatic thermogravimetric experiments. The synergistic effect on the co-combustion characteristics were investigated via performing sludge/coal co-combustion simulations under various conditions. The results showed that the sludge/coal co-combustion has positive synergistic effects on the co-combustion characteristics such as combustion rate, consumption of O2, and yield of CO2. By using the atomic labeling method, it was found that the combustion of sludge was inhibited while the combustion of coal was promoted during co-combustion process. The carbonaceous gas was found to be an important intermediate product in the generation of CO2. The synergistic effect promoted coal combustion because some ·OH radicals produced by the sludge attacked the aromatic ring structure in coal, which accelerated the formation of carbonaceous gas during sludge/coal co-combustion. This work provided new insight into the behaviors of municipal sludge/coal co-combustion.