Page 193 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

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for regimes under the loading point

W = expl —^-1 ; (33)

{200J

for regimes over the loading point

»T= —*• expl-^-}. (34)

The Reynolds numbers for the liquid and for the gas phase are defined as
follows:

= ^ and Re =6^^ ] , (35)
m
aju G l + 4/(d ca)
a.ft L
where d c is the column diameter.
For the liquid holdup over the loading point H& Billet [177] proposed
the equation

X-\ • 06)

U
where the index F" is for the flooding point.
The value H^F can be calculated by the equation

H dF =0.3741 e\^ \ . (37)

From equations (31) to (35) it is easy to see that the effect of the
column diameter is to be neglected for big columns.
The above presented equations for determination of the pressure drop of
irrigated packings are suggested only for a liquid which does not form froth.
The investigations [74, 75] show that the presence of froth can increase many