Page 248 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

238

Accepting that the effective surface area is equal to the wetted area of
the packing, Onda et al. [129], using own data and data of other investigators,
obtain the equations:

for Raschig rings

K
1 /3
lu3
Sh G=0.0142s R4'G(% Sc G ; (140)
for Berl saddles:

Sh G=0.0058e 0J4 (141)

where Ga G = —^-^- is the Galilei number for the gas phase calculated with
Mo
d h.
The comparison of equations (140) and (141) with the experimental
data is presented in Figs. 35 and 36.

8
e — • 1 e8
€.2 8 9
4
o 3 a 10 c
84 Bfl
»5 .12
aB »13 J
o? c 14 %
£0 ° \M
K 6 *• J If
V*
rf s
A \4 I

10' 1
8
6 A

4 e aio 1 4 e aio a 2 4 e aio 3
Fig. 35. Comparison of experimental data for gas-side controlled mass transfer for Raschig rings
with Eq. (140).