Premium
Gas–liquid mass transfer to single bubbles: Effect of surface contamination
Author(s) -
Vasconcelos Jorge M. T.,
Orvalho Sandra P.,
Alves Sebastião S.
Publication year - 2002
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.690480603
Subject(s) - mass transfer , dissolution , bubble , chemistry , pulmonary surfactant , contamination , thermodynamics , mass transfer coefficient , kinetics , chemical physics , mechanics , chromatography , physics , ecology , biology , biochemistry , quantum mechanics
The dissolution of single bubbles of gases of low solubility kept stationary in a downward stream of water was studied. In “clean” water, two regimes are identified. Initially, the process is fast, consistent with the theory for circulating bubbles. Then, the mass‐transfer rate falls sharply to that predicted for solid spheres. Transition times and transition diameters vary widely with experimental conditions. In untreated water, only the second regime is found. Results are explained in terms of the kinetics of trace surfactant accumulation at the interface. An adaptation of the stagnant‐cap model is proposed, with surface immobilization expressed in terms of interface dynamics. The model yields good prediction of the transition point for a very large set of conditions, including different gases at various concentrations in the liquid stream and a wide range of initial bubble diameters.