Modeling CO2 Mass Transfer Dynamics in Falling Liquid Films Over Textile Fiber Surfaces

CO2 absorption in falling liquid films is one of the methods for carbon capture to mitigate greenhouse gas emissions. The process can be enhanced through the application of biocatalytic textiles that provide multiphase reaction environment within the gas liquid contactor for the mass transfer of CO2 across the falling film. The biocatalytic textiles coated with immobilized enzymes enhance the absorption of CO2 in counter current gas liquid flow. The presence of textile fibers within the liquid film introduces additional complexity as the flow hydrodynamics within the liquid film is altered. The performance of gas liquid contactors is sensitive to the flow distribution within the liquid film. This study presents numerical simulation of CO2 physical absorption in falling liquid films supported by textile fibers. A transient computational multiphase fluid dynamics model is developed that incorporates textile fibers as impermeable cylindrical obstacles. Numerical simulations reveal the impact of flow obstruction on interface dynamics, which plays a crucial role in mass transfer phenomenon. The numerical framework is a powerful tool to model and visualize the interaction between gas-liquid interface and textile fibers. PHASTA, a finite element code was utilized to simulate counter current gas liquid flow, employing the level-set method to resolve gas-liquid interface. Absorption rates are estimated by calculating the concentration gradient at the gas-liquid interface, while the physical mass transfer coefficients are estimated to quantify the performance. This numerical framework can be used to investigate the impact of textile properties such as thread count, fiber diameter and orientation on the CO2 absorption process.