Experimental study of the dynamics and mass transfer behavior of carbon dioxide bubble at different constraint limits

The dynamic behavior of CO2 bubbles in MEA solutions at different constraint limits was investigated using a high-speed camera. We measured the morphological characteristics, velocity, and mass transfer coefficient of the bubbles as they ascended. The findings indicate that: The limitation of the bubble's movement influences its fluctuation during the ascent, with more confinement resulting in a more pronounced zigzag motion. In a confined area, the resistance encountered by a rising bubble is mostly due to drag force and wall shear force. When the confinement is less, the drag force becomes the dominant factor, but in larger confinements, the shear force takes precedence. Increased confinement of bubbles hinders the process of bubble surface renewal, as it leads to the accumulation of a substantial quantity of generating materials on the surface. When the bubble is not limited, its capacity to renew the surface increases, resulting in a bigger mass transfer coefficient.