Abstract
Toward the application of a downcomer with gas entrainment by liquid flowing downward to a gas-liquid contactor, mass transfer characteristics in the downcomer were experimentally studied. Aqueous sodium sulfite solution was used as the liquid and it was reacted with the oxygen in entrained air.
The specific gas–liquid interfacial area was larger in mixed flow than in slug flow. The maximum specific gas–liquid interfacial area appeared at a relatively high liquid flow rate in mixed flow, and increased with increasing downcomer diameter in the range of present experimental conditions. Bubble diameter decreased with liquid flow rate in slug flow and was almost unchanged in mixed flow. The liquid-phase mass transfer coefficient was higher in mixed flow than in slug flow.
