Numerical Study of Dry Reforming of Methane Using Internally Circulating Fluidized-Bed Reactors

Abstract

Numerical simulation was carried out to examine the performance of synthesis gas (syngas) production via dry reforming of methane (DRM) using an internally circulating fluidized-bed (ICFB) reactor. The ICFB was designed using a baffle plate and a gap below the baffle plate located at the center of the reactor. Particle circulation was achieved by using different reactant velocities at the two reactor inlets. It was found that the ICFB exhibited better DRM performance, characterized by conversions of CH₄ and CO₂, yields of H₂ and CO, and carbon yield, compared to packed-bed and conventional bubbling fluidized-bed (BFB) reactors under identical operating conditions. The DRM performance enhancement was due to the catalyst circulation. With a smaller catalyst size and higher packing height, DRM performance can be enhanced due to an increased degree of fluidization and catalyst loading. For the various inlet velocity ratio of the reactant in the ICFB operation, it was found that there appeared to be an optimum velocity ratio with a value of four that resulted in maximum conversions of CH₄ and CO₂ minimum carbon yield. At the reaction temperature of 800°C, the conversions of CH₄ and CO₂ were 96% and 88%, respectively, while the carbon yield was 0.024 mol/mol CH₄.