Computational Fluid Dynamics of Rectangular Monolith Reactor vs. Packed-Bed Column for Sorption-Enhanced Water-Gas Shift

Abstract

Abstract Sorption-enhanced water-gas shift (SEWGS) process is very attractive for an energy efficient pre-combustion CO2 capture, as it enables direct conversion of syngas into separate streams of H2 and CO2 at high temperatures and pressures. Using advanced computational fluid dynamics (CFD) methods, quantitative performance differences were assessed for rectangular channel monolith structures versus regular packed-bed structures when used for pre-combustion CO2 capture. Published data of breakthrough capacities at different pressures for CO2 and H2O were used to validate a multicomponent adsorption isotherm. A COMSOL 1D model was developed to describe CO2 adsorption in a fixed-bed reactor, filled with adsorbent pellets, to confirm the accuracy of the results compared to the existing studies, after which a 2D model was built simulating the adsorption step of a SEWGS process inside of a monolith reactor channel. Model predictions display an increase in productivity of adsorption in the case of monolith structures versus conventional packed-bed columns. Results will be used to improve the performance of experimental monolith structures undergoing SEWGS.