Parametric Analysis of Mass-Transfer Performance in CO2 Absorber Using Aqueous MEA and MEA/MDEA

To make the gas absorption process more economically viable, a rigorous design and operation strategy is an effective implementation. This work focuses on the development of a rigorous design and operation strategy for the absorber where the complicated mass-transfer of CO₂ with chemical reactions takes place. A series of absorption experiments were carried out in a bench-scale absorber packed with structured packings. Monoethanolamine (MEA) was used as absorption solvents. The absorption performance was analyzed and reported in terms of overall mass-transfer coefficient (K_Ga_e). The statistical factorial design analysis was performed to determine parametric influence and the synergy or interaction between process variables. The results show that CO₂ loading of solution is the most influential process variable on mass-transfer coefficient, followed by amine concentration, CO₂ partial pressure in feed gas, temperature, and liquid circulating rate, respectively. Liquid circulating rate interacts with amine concentration, while temperature appears to interact with all remaining variables. A second-order model of mass-transfer coefficient was successfully developed as a function of operating conditions. The knowledge obtained from this work can be used for developing a cost-effective strategy for design and operation of CO₂ absorber.