10. Combustion and Reacting Flows

In this study, numerical simulation was carried out to examine the performance of syngas production via dry reforming of methane (DRM) using packed-bed reactor (PB), bubbling fluidized-bed reactor (BFB), and internally circulating fluidized-bed reactor (ICFB) under various operating conditions. Effects of reaction temperature, reactant inlet velocity, CH4/CO2 feed ratio, catalyst loading, and catalyst particle diameter on the performance of DRM using ICFB were examined in detail. The simulated results indicated that the ICFB had the best DRM performance due to catalyst circulation inside the reactor from a decreased carbon formation point of view. With the increase in reaction temperature, conversions of methane and carbon dioxide, yields of hydrogen and carbon monoxide can be increased. By varying the inlet velocity ratio of the reactant in the ICFB operation, it was found that as the inlet velocity ratio increased, the performance of DRM was degraded due to decreased contact time between the reactant and catalyst. With molar CH4/CO2=1/0.5, lower methane conversion and higher carbon yield were resulted due to insufficient carbon dioxide supply. Reversely, higher methane conversion and lower carbon yield can be obtained when molar CH4/CO2=1/2. It was also found that the DRM performance can be enhanced by increased catalyst loading due to more catalysts involved in the reaction. Lastly, the effect of catalyst particle size on DRM performance was examined. It was found that as catalyst particle diameter becomes larger, the DRM performance will be lower due to lower fluidization extent.