Simulation of Aqueous Blend of Monoethanolamine and Glycerol for Carbon Dioxide Capture from Flue Gas

Abstract

This study investigated CO2 capture from flue gas by using glycerol as solvent. Absorption was simulated using a rate-based model with three cases under similar operating conditions. CO2 separation was first simulated using ENRTL-RK thermodynamic model with monoethanolamine (MEA) as solvent. CO2 absorption was then simulated using NRTL-RK thermodynamic model with glycerol solvent, and then an aqueous mixture of MEA/glycerol was also simulated using ENRTL-RK thermodynamic model. Simulation results confirm that glycerol can be used as promoter with MEA solvent to enhance CO2 capture. The optimal glycerol concentration for CO2 absorption is 10–40 wt %, in which 10 wt % glycerol exhibits the lowest CO2 concentration in the outlet gas from the absorber. The CO2 removal efficiency increases from 62.24% for 10 wt % MEA aqueous solution to 64.33% for the mixture of 10 wt % MEA–10 wt % glycerol aqueous solution. The CO2 removal efficiency for 10 wt % glycerol aqueous solution is 27.31%.