Surface Effects in Gas Absorption

Reaeration in open-channel flow

“…The effects of sewage effluents and settled sewage containing detergents were similar to the effects observed for mixed detergents, but the effects of sewage effluents and settled sewage were less when the detergents were not present. Gameson, Truesdale, and Varley (1956) Metzger (1968) and Mancy and Okun (1965) found in stirred-tank studies that the largest reduction in KL occurred for intermediate mixing intensities. Gameson, Truesdale, and Downing (1955) added detergents to a small English stream and found that there was no apparent relation between the reduction in KL and the detergent concentration, in the range from 0.5 to 2 mg/1.…”

“…Ms gram , and Metzger (1968) where ey is the eddy diffusivity for mass, and /8' is the turbulence parameter for the layer, such that \2 (67) Similarly, after applying the localized-mixing model to momentum transfer, Marchello and Toor obtained (68) where ev is the eddy diffusivity for momentum. Thus, if one can determine the momentum eddy diffusivity for a particular layer, one can solve equation 68 for /8' and determine the eddy diffusivity for mass for the layer from equation 66.…”

“…Eckenfelder, Raymond, and Lauria (1956) hypothesized that surfactants would reduce KL in two ways: first, by increasing the diffusional resistance through a reduction in the surface tension, and second, by decreasing the surface renewal rate through an increase in viscosity. Metzger (1968) studied the absorption of helium and nitrogen under identical mixing conditions in a stirred tank containing 0.5 mg/1 of ABS (alkyl benzene sulfonate), a surfactant. He found that the film thickness and surface-renewal parameters of the Dobbins (1956) film-penetration model were larger and smaller, respectively, than the values obtained for the same mixing conditions with distilled water.…”

Effect of Temperature on the Surface Tension of Soluble and Insoluble Surfactants of Hydrodynamical Importance

“…Many of these effects can be explained by virtue of the elasticity imparted to the interfacial region by the surfactant. Examples of important processes affected or caused by surfactants include (A) the damping of capillary waves, , (B) the modification of vortex-free surface interactions, − (C) the damping of subsurface turbulence, − (D) the modification of gas transport, − and (E) the alteration of wave breaking dynamics . Sarpkaya has given a comprehensive review of many of the studies cited above in addition to discussing the relevant hydrodynamical background.…”