Page 271 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

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The idea is that by changing the free cross-section of the elements with
their height, the gas flow is turbulized and the mass transfer coefficient
increases. Indeed, the effect of the cross-section reduction on the pressure drop
is significantly greater. That is why as it is easy to see from Fig. 64, the pressure
drop of this packing at a given volumetric mass transfer coefficient is many
times higher than that of the honeycomb packing with vertical walls, i.e.
without reduction of the cross- section with the height of the packing elements.

3.2.2.1.2. Performance characteristics of structured packings with vertical
smooth walls and their comparison with other types of packings

3.2.2.1.2.1. Pressure drop

3.2.2.1.2.1.1. Experimental data
Experimental date for the pressure drop of some packings with vertical
walls are presented in Fig, 50 to 53.

1 2
1
us 3-
d?
%
ft
M
1CP
8 MtW
WW
MM
Wm
w

I

$
i II
4 6 8 10° 2
w o,m/s

Fig. 50. Pressure drop of a ceramic honeycomb packing [144] wffii the following geometrical
characteristics: diameter of the incirele 20 mm; height of the elements A=61 mm; specific surface
2
3
2
3
area 151 mVm ; free volume 0.764 m'/ml 1- £=0.0139 m /m s; 2- £=0.0111 m'/m s; 3-
2
s
a
2
3
2
J
3
£=0.00834 m /m s; 4- £=0.00555 m /m s; 5- £=0.00277 m /m s; 6 -£=0.00139 m /m s; 7- dry
packing.