https://doi.org/10.1016/j.ccst.2022.100028
“The effect of solvent flow rate, in non-wetting mode, on the CO2 removal efficiency is shown in Fig. 9. At low liquid flow rates, the CO2 removal increases with increasing solvent flow rate, but it reaches a constant value at a certain flow rate (Fig. 9).
Fig. 9. Effect of solvent flow rate on the CO2 removal efficiency (gas flow rate = 6L/hr,Tgas=298K,C0=1400ppm,Cs=30wt%)
For example, for MDEA + KLys solution, increasing the liquid flow rate from 6 to 40 L/hr enhanced the CO2 removal efficiency from ⁓86% to ⁓96%. However, increasing the liquid flow rate larger than 30 L/hr did not have a significant effect on the CO2 removal efficiency. A similar trend was observed for other solvents. This can be attributed to chemical reaction between CO2 and amine solvents, where the main mass transfer resistance is in the gas phase with respect to the liquid phase mass transfer resistance, which is not significant. It is worth mentioning that increasing the solvent flow rate enhances the concentration gradients of absorbed CO2 in the liquid phase. This is due to high active reactant molecules of solvent, which improves the CO2 removal efficiency.
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