Foam drainage

Abstract

This review focuses on recent works on foam drainage + including both the advanced theoretical and experimental studies into foam drainage, standard and extended drainage theories with analytical and numerical solutions. Highlights of recent works include the effect of physico-chemical properties of the gas-liquid interface on foam drainage, and the foam-structure related properties governing the channel-and node-dominated drainage regimes. Important results obtained using the foam pressure drop technique which allows a systematic investigation of foam drainage with the constant and varying Plateau border radius are discussed. The free and forced drainage methods have also been the useful experimental techniques for revealing two important drainage regimes by the channels and the nodes. Finally, the influence of the syneresis on the foam stability and destruction is reviewed.

Foams built up by non-Newtonian polymeric solutions: Free drainage

“…11 and Table 1, f n~4 9 for a Newtonian liquid (n= 1) and immobile interface which is in complete agreement with the values reported earlier [8,18,35].…”

Bulk and surface rheology of Aculyn™ 22 and Aculyn™ 33 polymeric solutions and kinetics of foam drainage

“…drainage kinetics, is of great importance because it determines the rate of delivery of active substances to the target place. The considerable efforts have been made in theoretical description of foam drainage [2,[7][8][9][10][11][12] started by pioneering work of Leonard and Lemlich [13]. It was shown, that the drainage kinetics is different for the cases when dissipation occurs mainly in the Plateau borders or in nodes [14], for wet foams the contribution from lamellas can be also important [15].…”

Study on Streptomycin Sulfate Recovery by Batch Foam Separation

“…With the increase of the SDS concentration, more streptomycin molecules could combine with CH 3 (CH 2 ) 11 OSO À 3 , be adsorbed on the bubbles and so the recovery rate of streptomycin sulfate increased when the concentration of the surfactant SDS was less than the critical micelle concentration (CMC) (17). The foam with a higher surfactant concentration was characterized by smaller and more stable bubbles (18) and had higher liquid holdup (19,20), and so the enrichment ratio of streptomycin decreased. Therefore, the appropriate concentration of SDS was 0.3 g=L.…”