| 초록 |
The development of the sustainable energy system is one of the most crucial problems facing contemporary mankind to mitigate greenhouse gas emissions. Using molten-metal bubble columns (MMBCs), non-oxidative CH4 pyrolysis producing H2 and solid carbon has emerged for efficient low-carbon H2 production against steam-methane reforming (SMR). Since hydrodynamic parameters such as the gas holdup and bubble size have significant impacts on heat and mass transfer, understanding the hydrodynamics of MMBCs is crucial to determine optimal operating conditions and reactor design. In this study, a volume of fluid computational fluid dynamics (VOF-CFD) model coupled with a large eddy simulation (LES) turbulence equation was developed and validated for MMBCs. Using the validated CFD model, hydrodynamics of a CH4-Sn system were investigated in the near-bubbling field at 900 °C and 1 bar. The specific surface area between the gas and liquid phases varied from 12.6 to 22.3 m2/m3 in the bubbling flow regime. The VOF-CFD simulations near the nozzle can provide the bubble size generated from the gas distributor according to operational and geometrical modifications. |
