A numerical optimization study on the catalytic dry reforming of methane in a spatially resolved fixed-bed reactor

Fixed-bed reactors with a small tube-to-particle diameter ratio are typically used for highly exothermic or endothermic reactions. Flow, temperature and species distribution as well as the reaction rates are affected by the effect of the confining wall. In this study we have investigated numerically a spatially resolved fixed-bed including a detailed reaction mechanism for dry reforming of methane (DRM). Operating conditions in terms of feed composition, feed and heating temperature and feed mass flow could be identified, where the deactivation of the catalyst due to coking is prevented but still a reasonable conversion of methane and carbon dioxide as well as a high hydrogen selectivity can be achieved. Finally the need of a spatially resolved simulation is shown. While a pseudo-homogeneous 2D simulation needs significantly less computation time, it over predicts the conversion by approx. 20% due to an overestimated heat transfer.