Page 306 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

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The biggest part of the operating costs for this type of apparatuses is the
energy cost for covering the pressure drop. That is why the pressure drop per
one mass transfer unit can be used for comparison of the operating costs of
different packings for a given process [144].
In Fig. 64 such comparison between some highly effective packings and
a good honeycomb packing with vertical smooth walls in case of gas-film
controlled mass transfer is presented. The geometrical characteristics of the
compared packings are presented in Table 30.

Table 30, Geometrical characteristics of the packings compared in Fig. 64.
No Packing type Literature Size a £• L
a
z
3
3
mm m /m 3 m /m 3 m /(m s)
1 Impulse Packing [170] 50 103 0.83 2.8xl0" 3
2 Pall Ring [170] 50 120 0.78 2JxlO" J
3 Hiflow-ring [171] 25 192 0.92 2.8xl0" 3
4 Hiflow-ring [171] 50 110 0.93 2.8xlQ- 3
5 Hiflow-ring [171] 90 65 0.97 ISxlO" 3
6 Norpaek [172] 25 2.felO" 3
7 Tellerete [172] 25 2.8x10" 3
8 Ralu-Pack 250Y [173] 0.963 2.8xlG" 3
9 Euroform-PN [174] 4.2xlO" 3
10 Honeycomb Packing [174] 20*,60** 151 0.76 2.8xlO" 3
11 Kolar Packing [175], [169] 10*** 200 0.97 16.7xW 3
12 Honeycomb Packing, [176] 18.8-19.3* 185.5 0.83 2JxlQ" 3
Fig. 47 31**
* Diameter of the circle inscribed in the hexagon.
* * Height of the packing bodies.
*** Distance between the expanded metal sheets.