Oxygen Transfer in Surface Aeration Tank with Square Cross Section

Mass-Transfer Characteristics of Surface Aerators and Gas-Inducing Impellers

“…The mass-transfer rate was found to increase in the range of 0.38D < H < 1.2D and to be independent of the liquid height in the range of 1.2D < H < 4D. 5 For constant impeller submergence, Zlokarnik 1 found a relatively greater effect of the liquid height on the masstransfer rate than on the power consumption. The primary liquid circulation did not vary much with liquid height.…”

“…Backhurst et al 2 found that the mass-transfer rate per unit power consumption (R/P) was optimum at an impeller clearance of 2D and that, with a further increase in C, the value of R/P decreased. Backhurst et al 2 and Takase et al 5 reported different effects of impeller clearance. Given that Backhurst et al 2 covered a wide range of reactor scales, their results are more important for scale-up than those of Takase et al 5 Different types of correlations are reported to account for the effect of aerator scale.…”

“…Backhurst et al 2 and Takase et al 5 reported different effects of impeller clearance. Given that Backhurst et al 2 covered a wide range of reactor scales, their results are more important for scale-up than those of Takase et al 5 Different types of correlations are reported to account for the effect of aerator scale. Fuchs et al 6 reported that, at the same value of P/V, the value of k L a decreases with increasing aerator scale.…”

“…The effect of this parameter can also be viewed as the effect of the total liquid height ( H = S + C ) at constant impeller submergence ( S ). Takase et al carried out experiments at just-submerged condition and found that a vortex was formed for liquid heights of H < 0.38 D . The mass-transfer rate was found to increase in the range of 0.38 D < H < 1.2 D and to be independent of the liquid height in the range of 1.2 D < H < 4 D .…”

Effect of number of turbine impellers on surface aeration in laboratory fermentor

“…2s,7,'2, 13 Surface aeration occurs even when agitated vessels are being sparged, though it is not easily seen. Since the first investigation carried out by Calderbank, 16217 considerable work has been done toward better understanding of the mechanism of surface aeration and in establishing a correlation for quantitative determination of the surface aeration intensity.…”