Mean fluid temperature data pertaining to the effect of porosity on the methanol steam reforming and decomposition processes in microchannel reactors

The mean fluid temperature data are obtained for illustrating the effect of porosity on the methanol steam reforming and decomposition processes in microchannel reactors. The autothermal reactor is configured for simultaneous oxidation and steam reformation of methanol. The reactor system comprises two separate sets of flow channels, which are located between spaced, highly heat-conductive metal or ceramic separating walls. The medially located, bi-catalytic separating walls have different catalysts on opposed surfaces. These catalysts are selected for the particular reaction taking place in the adjacent reaction zone. The reactor provides for continuous and simultaneous reaction of two different process reaction streams in the channels defined between the walls, wherein a first process reaction stream undergoes a high temperature exothermic reaction in the first set of flow channels and a second process reaction stream undergoes an endothermic heat-consuming reaction in the second set of flow channels separated from the first set of flow channels by the heat transfer separating walls. More specifically, the reactor system includes a set of reforming channels for steam reformation of methanol and a set of oxidation channels for heating the reactor system to operating temperature. A separating wall therefore separates two adjacent reaction zones and also functions to transfer heat from the oxidation occurring at the catalyst surface in the oxidation zone directly to the reforming catalyst coated on the opposed surface. To facilitate 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 fluid mechanics is used. ANSYS FLUENT handles thermodynamic properties, transport properties, and chemical kinetics. The contribution of homogeneous reactions involving gas-phase species is insignificant under the conditions of interest. The boundary conditions relate macroscopic fluid flow at a catalytically active surface to the rates of surface reactions. Heterogeneous reactions at a catalytically active surface affect the heat and mass balance at the surface. In addition, surface reactions create sources and sinks of chemical species on the surface and in the gas phase. Chemical reactions involving surface species significantly influence the boundary conditions. The endothermic process is modeled in such a way as to take into account methanol steam reforming and decomposition and the water-gas shift reaction.
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

本数据集的流体平均温度数据用于阐明孔隙率对微通道反应器内甲醇水蒸气重整与分解过程的影响。该自热式反应器设计用于同步实现甲醇的氧化反应与水蒸气重整反应。本反应器系统包含两组独立的流道，两组流道置于间隔排布的高导热金属或陶瓷分隔壁之间。位于中间的双催化分隔壁的两侧表面负载有不同的催化剂，所选用的催化剂需适配相邻反应区内发生的特定反应。本反应器可实现分隔壁之间流道内两种不同工艺反应物流的连续同步反应：第一组流道内的第一股工艺反应物流发生高温放热反应，第二组流道内的第二股工艺反应物流则发生吸热耗热反应，两组流道通过导热分隔壁相互隔开。
更具体而言，本反应器系统包含一组甲醇水蒸气重整流道，以及一组用于将反应器加热至工作温度的氧化流道。因此，分隔壁不仅可分隔两个相邻的反应区，还可将氧化区催化剂表面发生的氧化反应产生的热量，直接传递至另一侧表面负载的重整反应催化剂。
为便于对包含气相与表面物种的复杂流动化学反应系统的传递现象与化学动力学进行建模，本研究采用稳态分析方法，并结合流体力学理论。ANSYS FLUENT软件用于处理热力学性质、传递性质与化学动力学相关计算。在所关注的工况条件下，涉及气相物种的均相反应的贡献可忽略不计。边界条件将催化活性表面处的宏观流体流动与表面反应速率关联起来。催化活性表面处的非均相反应会影响该表面的热平衡与质量平衡。此外，表面反应会在表面及气相中形成化学物种的源与汇。涉及表面物种的化学反应会对边界条件产生显著影响。本研究对吸热过程进行建模时，充分考虑了甲醇水蒸气重整、分解以及水煤气变换反应。

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