Volumetric absorption coefficient (
ka)
lg, specific interfacial area
alg and mass transfer coefficient
klg were measured for two-phase cocurrent flow of O
2-water and CO
2-NaOH systems in a column packed with glass spheres of 3 different sizes (2.59-12.2 mm). Values of (
ka)
lg observed were so high as to be that can be hardly attainable in conventional gas-liquid contactors. This is due to large
alg of small bubbles dispersed in liquid where
alg very often exceeds the geometrical surface area of packing. Values of
klg range from 2 to 8×10
-4m/sec, which are comparable to that of circulating bubbles in the usual systems. The effect of superficial gas velocity on (
ka)
lg and
alg is much greater than that in a countercurrent packed column, while the effect of liquid velocity is approximately same. A liquid-phase energy loss
El per unit volume of liquid contained in a bed was newly defined as a measure of microscopic flow intensity and was used for discussion and correlation of mass transfer properties. It was found that the bubble diameter is proportional to
El-2/5.
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