Process modeling and sensitivity analysis of intensified post-combustion CO2 capture process by polyamine solution in a rotating packed bed

Abstract

This study explores a modeling-optimization approach for CO₂ capture using polyamine, diethylenetriamine (DETA), in a rotating packed bed. The developed model is based on a rate-based approach and the Deshmukh-Mather model as the thermodynamic framework, which is incorporated into the rate-based model. Various mass transfer correlations are employed to conduct a sensitivity analysis based on an orthogonal array design. The model outcomes were validated by comparing them with experimental data from the literature. All profiles along the radial direction were predicted, including gas and liquid concentrations (both molecular and ionic species), gas and liquid flow rates, temperatures, and pressure. The impact of RPM on CO₂ capture level was examined under different amine concentrations, amine temperatures, amine and gas flow rates, and pressure. Additionally, the effect of RPM on liquid hold-up was analyzed. The findings indicate that the rate-based model accurately predicts the experimental data, with an AARD of 3.015%. Furthermore, the most suitable correlations for mass transfer coefficients in the gas and liquid phases, as well as the effective surface area, were identified using sensitivity analysis to evaluate CO₂ absorption by the DETA solution in an RPB. Finally, the OAD method was employed for statistical optimization and ranking of key operating parameters that simultaneously influence CO₂ capture performance. The RPB absorber was optimized based on three factors: rotational speed, lean amine temperature, and flow rate. The rate-based model was employed to predict the response values (CO₂ capture level) in the OAD method. The OAD outcomes reveal that rotational speed and solvent temperature have the greatest impact on CO₂ capture level, respectively. Furthermore, a comparative analysis demonstrates that the RPB exhibits superior mass transfer performance under identical operating conditions compared to a conventional packed column with Dixon ring packing.