Modeling and validation of a pilot-scale aqueous mineral carbonation reactor for carbon capture using computational fluid dynamics

In anticipation of the successful establishment of carbon capture, utilization, and storage (CCUS) technology, a pilot-scale aqueous mineral carbonation plant, that removes CO2 through a reaction with a Ca(OH)2 solution, was built in Incheon, South Korea. Using computational fluid dynamics (CFD), two reactors with a diameter of 2.2 m and a height of 6.0 m were modeled and validated for reactor scale-up and optimization. Because a direct simulation of bubble breakage, coalescence, and interphase mass transfer results in enormous computational costs for modeling the pilot-scale multiphase reactor, a CFD-lumped correlation model was introduced to simulate a large reactor; this resulted in acceptable computational costs and maintained the simulation accuracy. In order to ensure the acceptability of the CFD model, two-step verification was conducted. The CFD model results were compared with the experimental data and published empirical correlations with regard to the gas holdup, interfacial area, and mass transfer coefficient. Subsequently, the CO2 removal efficiencies of the CFD model were compared with the pilot-plant data. The errors of the CFD model for three hydrodynamic parameters and the CO2 removal efficiencies were in the range of 1-8%. The validated CFD model will be used for designing a four times larger mineral carbonation reactor, that will be built in 2017.