Comparison of CFD Simulation and Simplified Modeling of a Fluidized Bed CO2 Capture Reactor
Comparison of CFD Simulation and Simplified Modeling of a Fluidized Bed CO2 Capture Reactor
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DOI：
10.1515/ijcre-2015-0058
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发表时间：
2015-11
影响因子：
1.6
通讯作者：
Daoyin Liu;Zhonglin Zhang;Yaming Zhuang;Xiaoping Chen
中科院分区：
文献类型：
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作者：
Daoyin Liu;Zhonglin Zhang;Yaming Zhuang;Xiaoping Chen
摘要 在流化床反应器中使用固体吸附剂捕获二氧化碳是一项有前途的技术。多相 CFD 模型越来越多地用于研究反应堆，但很难对所有现实细节进行建模，并且需要大量的计算时间。在本研究中，开发了多相 CFD 模型（即与反应耦合的 CFD-DEM 模型）和简化反应器模型（即活塞流模型和鼓泡两相模型）来模拟流化床 CO2 捕集反应器。比较是在从固定床到流化床的不同气体速度下进行的。基于 DEM 的模型揭示了具有颗粒流动力学的 CO2 吸附过程的详细视图，基于此可以评估简化模型中的假设。活塞流模型预测总体上与DEM模型表现出相似的趋势，但存在数量上的差异；因此，它可以用来确定反应堆的性能极限。鼓泡两相模型比活塞流模型提供更好的预测，因为包含了气泡对相间传质和反应的影响。未来，多相CFD模拟与简化反应器模型的更紧密结合将可能成为CO2捕集流化床反应器的有效设计方法。
Abstract CO2 capture using solid sorbents in fluidized bed reactors is a promising technology. The multiphase CFD model is increasingly developed to study the reactors, but it is difficult to model all the realistic details and it requires significant computational time. In this study, both the multiphase CFD model (i.e., CFD-DEM model coupled with reaction) and the simplified reactor models (i.e., plug flow model and bubbling two-phase model) are developed for modeling a fluidized bed CO2 capture reactor. The comparisons are made at different gas velocities from fixed bed to fluidized bed. The DEM based model reveals a detailed view of CO2 adsorption process with particle flow dynamics, based on which the assumptions in the simplified models can be evaluated. The plug flow model predictions generally show similar trends to the DEM model but there are quantitative differences; thus, it can be used to determine the reactor performance limit. The bubbling two-phase model gives better predictions than the plug flow model because the effect of bubbles on the inter-phase mass transfer and reaction is included. In the future, a closer combination of the multiphase CFD simulation and the simplified reactor models will likely be an efficient design method of CO2 capture fluidized bed reactors.