Carbon dioxide absorption and anti-clogging performance of a novel millimeter-scale channel absorber

This study proposes a novel millimeter-scale channel absorber for the first time, which involves carbon dioxide (CO2) absorption in the channel to achieve efficient CO2 absorption while avoiding clogging. CO2 absorption experiments were conducted on such a channel absorber with an inner diameter of 2.3 mm to study its CO2 mass transfer and absorption characteristics. Al2O3 particles were introduced as solid impurities to evaluate its anti-clogging performance. The experimental results showed that a stable Taylor flow could be formed in the channel in appropriate gas and liquid flowrate ranges. The liquid-side volume mass transfer coefficient (KLa) reached 0.34 s−1 using a 6% DEA solution as the absorbent, which was approximately one order of magnitude higher than that of the conventional packed towers. When Al2O3 to a maximum extent of 2 wt% was added into the absorbents, no clogging was observed, and the values of KLa even increased. Due to the excellent CO2 absorption mass transfer and anti-clogging performance, millimeter channel absorbers have promising industrial applications for CO2 absorption. Therefore, means and application scenario for applying millimeter-scale channel absorber in the industrial CO2 absorption have been proposed.