Enhancing CO₂ capture efficiency: CFD investigation of gas–liquid self-suction reactor configurations

The separation and removal of industrial waste gases (such as CO₂) has broad prospects. Efficient gas separation and removal equipment is the key to the purification of industrial waste gases. In this study, a new type of gas separation and purification reaction equipment was designed that can effectively improve the capture of CO₂. The Propeller self-suction impeller coupled with the dynamic membrane–aeration impeller (Propeller + DMAI, also SDMSR) is the best impeller combination, achieving a gas holdup (ε_G) of up to 11.4 % and a volume mass transfer coefficient (k_La) of up to 0.061 s⁻¹. Compared with other combinations, ε_G and k_La are significantly improved. Additionally, compared with the dynamic membrane–stirred reactor (DMSR) and self-suction stirred reactor (SSR), SDMSR enhances CO₂ mass transfer and gas recovery, with a CaCO₃ nucleation rate constant of 1.37 s⁻¹, which is 11.38 % and 52.22 % higher than DMSR and SSR, respectively. In summary, this study provides a reference for the separation and purification of special gases.