MULTIPHYSICS SIMULATION OF SUPERCRITICAL CO2 GASIFICATION FOR HYDROGEN PRODUCTION

Abstract

Among the gasification technologies being considered, supercritical carbon dioxide (sCO<sub>2</sub>) gasification offers certain advantages for direct fired systems and is the subject of this work. A reacting computational fluid dynamics (CFD) model was developed using Ansys Fluent in order to investigate the impact of various operating parameters on syngas composition. The model was validated using available data in the literature. Simulations were conducted over a wide range of operating parameters with the goal of optimizing hydrogen production for the considered reactor. The results from the simulations identified a positive correlation between slurry loading and hydrogen production, with slurry loadings of 80% resulting in an average outlet hydrogen mole percent of 25.4%. Reactor temperature and pressure were found to have a limited impact on H<sub>2</sub> production at the conditions of interest. Additionally, the simulations indicated that oxygen mass flowrate has less of an impact on hydrogen production at higher slurry loadings. Hydrogen content at conditions relevant to sCO<sub>2</sub> gasification is comparable to other slurry-fed gasifiers, while CO/CO<sub>2</sub> ratios far exceed those of widely employed dry or slurry-fed gasifiers, highlighting the need for experimental investigation.