Numerical simulation of low-concentration CO2 adsorption on fixed bed using finite element analysis

Accurately predicting distributions of concentration and temperature field in fixed-bed column is essential for designing adsorption processes. In this study, a two-dimensional (2D), axisymmetric, nonisothermal, dynamic adsorption model was established by coupling equations of mass, momentum and energy balance, and solved by finite element analysis. The simulation breakthrough curves fit well with the low-concentration CO2 adsorption experimental data, indicating the reliability of the establishedmodel. The distributions of concentration and temperature field in the column for CO2 adsorption and separation from CO2/N-2 were obtained. The sensitivity analysis of the adsorption conditions shows that the operation parameters such as feed flowrate, feed concentration, pellet size, and column height-to-diameter ratio produce a significant effect on the dynamic adsorption performance. The multi-physics coupled 2D axisymmetric model could provide a theoretical foundation and guidance for designing CO2 fixed-bed adsorption and separation processes, which could be extended to other mixed gases as well. (C) 2020 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

Automated summary

A 2D, axisymmetric, nonisothermal, dynamic adsorption model was established and sensitivity analysis showed significant effects of operational parameters on dynamic adsorption performance. The model provides a theoretical foundation for designing CO2 fixed-bed adsorption and separation processes.