Modeling of coal char gasification in coexistence of CO2 and H2O considering sharing of active sites
Modeling of coal char gasification in coexistence of CO2 and H2O considering sharing of active sites
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DOI：
10.1016/j.fuel.2011.11.030
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发表时间：
2013-01-01
期刊：
影响因子：
7.4
通讯作者：
Hara, Saburo
中科院分区：
文献类型：
--
作者：
Umemoto, Satoshi;Kajitani, Shiro;Hara, Saburo
在煤气化炉中，CO2气化和H2O气化同时发生。许多研究人员分别建立了CO2气化模型和H2O气化模型。只有几个模型解释了二氧化碳气化和H2O气化之间的竞争。根据活性中心的性质，这些模型分为两类。一些模型假设CO2气化和H2O气化发生在不同的活性中心，而另一些模型则假设所有的活性中心都是共享的，并且对CO2和H2O气化都是共同的。有些煤在CO2和H2O共存的情况下，其气化反应速率不能用常规模型描述。在本研究中，对Langmuir-HinShelwood气化模型进行了修正，以解释CO2和H2O对焦炭气化的影响。在提出的模型中，CO2气化和H2O气化部分共享活性中心。利用降管炉在常压和1673K条件下热解制得煤焦，在不同温度下用加压降管炉(PDTF)和热重分析仪(TGA)与CO2和H2O气化。与传统模型相比，该模型能更准确地描述实验中的气化反应速率。(C)2011爱思唯尔有限公司。保留所有权利。
In a coal gasifier, CO2 gasification and H2O gasification occur at the same time. Many researchers have constructed CO2 gasification model and H2O gasification model separately. Only a few models explain the competition between CO2 gasification and H2O gasification. These models are divided into two types according to the properties of the active sites. Some models assume that CO2 gasification and H2O gasification occur at separate active sites, whereas others assume that all of the active sites are shared and are common to both CO2 and H2O gasification. There are some coals whose gasification reaction rates, with CO2 and H2O in coexistence, cannot be described by the conventional models. In this study, a Langmuir-Hinshelwood type gasification model was modified to explain the char gasification by CO2 and H2O. In the proposed model, CO2 gasification and H2O gasification partially share active sites. Coal chars, which were prepared through pyrolysis using a drop tube furnace at ambient pressure and 1673 K, were gasified with CO2 and H2O using a pressurized drop tube furnace (PDTF) and a thermogravimetric analyzer (TGA) at various temperatures. The proposed model was found to describe the gasification reaction rates of the experiments more accurately than the conventional models. (C) 2011 Elsevier Ltd. All rights reserved.