Page 232 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

222

'neg.syst

where the Marangoni number Ma is given by the equation

dax-x* HTU L
, (108)
dx D Lft L HTU oL

Table 14. Characteristics of the packings used in determination of the constants of Eq.{105)
No. Packing Specific surface Column diameter Author
2
m /m 3 Mm
1 Ceramic rings 25.3x25.3x3 mm 210 190 [105]
2 Ceramic rings 25.0x15.9x3 mm 222* 190 [105]
3 Ceramic rings 25.3x10.9x3 mm 237* 190 [105]
4 Ceramic Intalox saddles 35 mm 173* 190 [105]
5 Ceramic Intalox saddles 50 mm 125' 500 [105]
6 Ceramic Intalox saddles 70 mm 86* 500 [105]
7 Plastic Pall rings 50 mm 130* 500 [105]
8 Plastic rings 25.3x25.3x3 mm 210* 190 [105]
9 Ceramic rings 15x15x2 mm 364 121 [106]
10 Ceramic rings 25x25x3 mm 190 121 [106]
11 Ceramic rings 25x25x3 mm 203 500 [107]"
12 Ceramic rings 50x50x5 mm 89.5 500 [107]"
13 Ceramic Pall rings 50x50 mm 125 500 [107]"
14 Ceramic Raschig rings 38x38 mm 130 500 [108]
15 China Pall rings 38x35 mm 130 500 [108]
16 Ceramic Intalox saddles 38 mm 160 500 [108]
The specific surface of the packing included also the surface of the column wall. For
determination of the effective surface the method of Danckwerts is used.
** The data are obtained using the method of Shulman.