Process Safety and Environmental Protection, Vol.146, 54-68, 2021
Mass transfer performance of carbon dioxide absorption in a packed column using monoethanoleamine-Glycerol as a hybrid solvent
Environmental concerns caused by chemical solvents need be managed through the advantages of hybrid bio-sourced solvents for CO2 capture. On the other side, to accurately predict the height of a CO2 absorption packed column, it is essential to estimate the mass transfer coefficients. This paper provides the experimental results of mass transfer performance of the aqueous mixture of MEA + Glycerol, as an industrially eco-friendly hybrid solvent, instead of a typical commercial alkanolamine solvent for CO2 capture in a laboratory-scale absorption packed column. For the first time, a predictive statistical model was built to investigate the influence of process variables, involving absorption temperature (30-45 degrees C), inlet gas flow rate (4-6 L/min), the initial solvent concentration of glycerol (5-15 wt %), and MEA (10-30 wt %) on the CO2 removal efficiency (e(f)), and the volumetric overall gas-phase mass transfer coefficient (K(G)a(V)) in the CO2 +MEA + Glycerol system. The results of CO2-absorption showed that rising the glycerol concentration from 5 % to 15 % enhances the values of e(f) and K(G)a(V) by 4.5 % and 24.62 %, respectively, when the other three variables are considered fixed at their midpoints. Therefore, the presence of glycerol, as the promoter in a hybrid mixture of MEA-Gly, significantly gives rise to the mass transfer coefficient and CO2 removal efficiency. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
Keywords:Absorption;Carbon dioxide;Glycerol;Monoethanolamine;Overall gas-phase mass transfer coefficient;Packed bed column