Catalytic oxidation process data at different pressures pertaining to the coupling of exothermic and endothermic reactions in adiabatic microchannel reactors

The catalytic oxidation process data at different pressures are obtained for the coupling of exothermic and endothermic reactions in adiabatic microchannel reactors. The reforming process proceeds in one set of the channels through which the endothermic reactants flow, and the exothermic oxidation process proceeds in the second set of the channels. Exothermic and endothermic reactions take place simultaneously whereby the heat required for the latter is supplied by the former. Heat transfer occurs via conduction through the walls of the reactor. For the endothermic reaction, the structure is especially effective because both the internal surfaces of the walls are coated with structured catalysts, which is capable of providing more efficient heat exchange and minimizing the problem of loss of catalytic activity. Such a reactor system is typically adiabatic in nature, meaning no heat is added in addition to the exothermic reaction heat release. The reactor system offers relatively simple designs and operation. The reactor system is in the form of a catalytic coating on a substrate composed of ceramic or metal walls defining straight reforming or oxidation channels which are parallel to each other and to the axis of the reactor. Relatively high mass transfer is provided by using high cell density channels, namely low hydraulic diameter channels. The design increases the number of boundary layers between a fluid and a reactor wall by a factor of one hundred or more, and boundary layers are known to impede heat transfer. However, relatively high heat transfer is provided. To facilitate computational modeling of transport phenomena and chemical kinetics in the flowing system of complex chemical reactions involving gas-phase and surface species, steady-state analyses are performed and computational fluid dynamics is used. ANSYS FLUENT is applied to the problem involving surface chemistry. The first type is a species in the gas phase above the surface. A surface species is defined to be the chemical species at the gas-solid interface. A surface does not necessarily have to be flat, and each surface species occupies one surface site. A site is considered to be a position or location on the surface at which a species can reside. A site does not necessarily have a composition itself or have to be a particular atom, and the total number of sites per unit area is conserved. Therefore, the sum of the site fractions of the species on the sites is unity. The contribution of homogeneous chemical reactions involving gas-phase species is insignificant under the conditions of interest. Contributor: Junjie Chen, E-mail address: [e-mail], ORCID: 0000-0002-5022-6863, Department of Energy and Power Engineering, School of Mechanical and Power Engineering, Henan Polytechnic University, 2000 Century Avenue, Jiaozuo, Henan, 454000, P.R. China本数据集获取了绝热微通道反应器（adiabatic microchannel reactors）内放、吸热反应耦合过程在不同压力下的催化氧化（catalytic oxidation）工艺数据。重整工艺（reforming process）在一组通道内进行，该通道为吸热反应物的流动通道；放热氧化工艺则在另一组通道内开展。放热与吸热反应同步进行，后者所需的热量由前者提供。热量通过反应器壁面以传导方式进行传递。针对吸热反应而言，该反应器结构效果尤佳，因为反应器壁面的两侧内表面均涂覆有结构化催化剂（structured catalysts），可实现更高效的热交换，并最大限度降低催化活性流失问题。此类反应器系统本质上通常为绝热体系，即除放热反应释放的热量外，无额外热量输入。该反应器系统设计与操作均相对简便。该反应器系统以催化涂层的形式附着于基底之上，基底由陶瓷或金属壁面构成，壁面界定出彼此平行且与反应器轴线平行的直形重整通道与氧化通道。采用高孔密通道（即低水力直径通道）可实现较高的传质效率。该设计将流体与反应器壁面之间的边界层数量提升了百倍乃至更多，而边界层通常会阻碍热传递，但本系统仍可实现较高的换热效率。为便于对包含气相与表面物种的复杂流动化学反应体系内的传递现象与化学动力学开展计算建模，研究采用了稳态分析方法，并运用了计算流体动力学（computational fluid dynamics）技术。针对涉及表面化学的问题，采用ANSYS FLUENT软件进行求解。第一类为表面上方气相中的物种。表面物种指的是气固界面处的化学物种。表面未必为平面，且每个表面物种均占据一个表面位点。位点被定义为表面上可供物种附着的位置。位点本身未必具有特定组成，也不必对应某一特定原子，且单位面积内的位点总数保持恒定。因此，附着于位点上的各物种的位点分数之和为1。在研究关注的工况条件下，涉及气相物种的均相化学反应的贡献可忽略不计。 贡献者：陈俊杰，电子邮箱：[e-mail]，ORCID：0000-0002-5022-6863，河南理工大学机械与动力工程学院能源与动力工程系，河南省焦作市世纪大道2000号，454000，中华人民共和国