Modeling of a 120 kW chemical looping combustion reactor system using a Ni-based oxygen carrier
Modeling of a 120 kW chemical looping combustion reactor system using a Ni-based oxygen carrier
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DOI：
10.1016/j.ces.2008.09.014
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发表时间：
2009
影响因子：
4.7
通讯作者：
Philipp Kolbitsch;T. Pröll;H. Hofbauer
中科院分区：
文献类型：
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作者：
Philipp Kolbitsch;T. Pröll;H. Hofbauer
介绍了一种用于研究双循环床(DCFB)反应器系统中化学链燃烧(CLC)的模拟工具。CLC是一种具有CO2分离特性的新型燃烧过程，由两个沸腾床反应器、一个空气反应器(AR)和一个燃料反应器(FR)组成。在两个反应堆之间循环的固体氧气载体(OC)输送燃烧所需的氧气。在DCFB概念中，AR和FR都被设计为循环床(CFB)。每个CFB都使用一个非常简单的结构进行建模，在该结构中，反应气体只与一定比例的混合良好的固体相接触。固体沿高度轴的分布由含气率分布定义。表征气固接触的不同参数被合并为一个参数：暴露在塞流中气体的固体百分比(φS，岩心)。利用该模型对维也纳工业大学120kW DCFB化学循环燃烧器的性能进行了研究。这个试验台是为镍基OC和天然气燃料而设计的。确定了反应器温度、固体循环速度、空燃比和燃料功率对反应的影响。此外，根据应用的动力学数据，只有当AR固体库远远大于FR固体库时或当两个反应器都很大时，AR中的OC才被完全氧化。为了比较不同的反应器系统，研究了AR和FR之间固体分布的影响，并报道了气体和固体的转化率。
A modeling tool for the investigation of chemical looping combustion (CLC) in a dual circulating fluidized bed (DCFB) reactor system is introduced. CLC is a novel combustion process with inherent CO2separation, consisting of two fluidized bed reactors, an air reactor (AR) and a fuel reactor (FR). A solid oxygen carrier (OC) that circulates between the reactors, transports the necessary oxygen for the combustion. In the DCFB concept both AR and FR are designed as circulating fluidized beds (CFBs). Each CFB is modeled using a very simple structure in which the reacting gas is only in contact with a defined fraction of the well mixed solids. The solids distribution along the height axis is defined by a void fraction profile. Different parameters that characterize the gas–solids contact are merged into only one parameter: the fraction of solids exposed to the gas passing in plug flow (φs,core). Using this model, the performance of the 120kW DCFB chemical looping combustor at Vienna University of Technology is investigated. This pilot rig is designed for a Ni-based OC and natural gas as fuel. The influence of the reactor temperatures, solids circulation rate, air/fuel ratio and fuel power are determined. Furthermore, it is shown that with the applied kinetics data, the OC is only fully oxidized in the AR when the AR solids inventory is much larger than the FR solids inventory or when both reactors are very large. To compare different reactor systems, the effect of the solids distribution between AR and FR is studied and both gas and solids conversions are reported.