Page 284 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

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phase flows along: a vertical surface of the packing elements and a horizontal
surface of the region of contact of two adjacent packing rows. The conditions
for the liquid flow, and consequently for the dynamic holdup, along the two
surfaces are different. That is why the equation for calculation of the dynamic
holdup for these packings must be written as a sum of two terms, one for every
type of packing surface. By means of such considerations the following
equation is proposed [164].

_fl.a«
H m = 0.56 Frl
(184)
6
+ 6.395 xlO (l -
The arithmetical mean error is 4.7% and the maximal error is 20%.
The experimental constants are obtained based on the same
experimental data as for Eq. (183).
A comparison between the experimental data for lie packings presented
in Table 26 and those calculated using equation (184) is presented in Fig. 56.

2
1Q" -

Fig. 56. Comparison of the experimentel data for dynamic holdup under the loading point end the
results calculated by Eq. (184) (see Table 26 for explanation of the data points).