Performance of ethanol steam reforming in a membrane-assisted packed bed reactor using multiscale modelling

Ethanol steam reforming in a membrane-assisted packed bed reactor is a promising hydrogen production method. In this work, a computational fluid dynamics (CFD) simulation is conducted to explore the catalytic reforming process from the macroscale (bed volume) and the microscale (particle) in a membrane reactor, where the catalytic bed is modeled via the porous media model with the implementation of the intrinsic kinetics with internal diffusion inside the particle and membrane separation model. The effects of particle size and porosity on gas diffusion and reforming performance are also evaluated. The results reveal that the membrane separation will limit the gas species external diffusion in the bed, especially for large-size catalyst particles. An increase of catalyst porosity can enhance the membrane-enhanced reforming effect. The internal diffusion plays a more significant role in the global reaction rate at low heights of the reactor.