Hydrogen mole fraction data associated with the effect of pressure on the species distribution in autothermal microchannel reactors
Description
The hydrogen mole fraction data are obtained for illustrating the effect of pressure on the species distribution in autothermal 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. There are multiple possibilities for the arrangement of the oxidation channels and the reforming channels for heating, such as co-current, countercurrent, or cross-flow modes. The two separate sets of flow channels are arranged in a co-current flow configuration. The reactor system is operated using excess air and water steam. Methanol and air are mixed homogeneously and the mixture is fed directly into the oxidation channels in a specific ratio. Preferably, excess water steam is provided to the reactor to increase efficiency and to maintain operability, for example, to prevent carbon formation. 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. To facilitate computational modeling of transport phenomena and chemical kinetics in the flowing system of complex 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. ANSYS FLUENT handles thermodynamic properties, transport properties, and chemical kinetics. Contributor: Junjie Chen, E-mail address: koncjj@gmail.com, 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
Files
Steps to reproduce
Physical properties depend on temperature and composition. The governing equations are solved numerically for the conservation of mass and momentum and for energy and species.