Page 256 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

246

Table 21. Packings used for determination of the experimental constants in Eq. (153)
z
Type and size of packings a m /m 3 Absorbed gas Author Symbol
Polypropylene Pall rings 50 mm 130 CO 2 Kolev [34] o
Ceramic Intalox Saddles 50 mm 125 COj Kolev [34] •
Ceramic Intalox Saddles 70 mm 80 CO 2 Kolev [34]
Rasehig ring 253x253x3 mm 210 CO 2 Kolev [i] ©
Shortened rings 25xl59x3mm 222 COj Kolev [8] e
Shortened ring 25x109x3 mm 237 CO 2 Kolev [8] e
Rasehig rings 6 mm 688 O 2 Qnda [135] e
»
Rasehig rings 8 mm 520 O 2 Onda [135]
Rasehig rings 10 mm 420 o 2 Onda [135] c
Berl saddles 12,7 mm 374 O 2 Sherwood [137] A
Berl saddles 25.4 mm 236 O 2 Sherwood [137] A
Berl saddles 37 mm 163 O 2 Sherwood [137] v
Rasehig rings 12,7 mm 374 O 2 Sherwood [137] •
Rasehig rings 25.4 mm 190 O 2 Sherwood [137] a
Rasehig rinp 37 mm 118 O 2 Sherwood [137] •
Rasehig rings 50 mm 95 o 2 Sherwood [137]
Rasehig rings 25 mm 170 O 2 Ramm [140] m
Rasehig rings 98,5 mm 89.5 Oa Ramm [140] H
Ceramic Pall rings 50 mm 125 0 2 Ramm [140] n

The investigation of Delaloye et al. [301], where the purpose is to
determined the influence of the liquid viscosity on the liquid-side controlled
1 2
mass transfer coefficient shows that k La/ D ^ is inverse proportional to the
square root of the viscosity. The difference between the power at the viscosity
obtained by them and that in equation (153) is only 0.06. This difference is
within the limits of the experimental error in this type of investigations,
especially taking into account the error in the calculation of the diffusiviry
which depends strongly on the viscosity.
A great disadvantage of many of the equations is that when presenting
them in dimensionless form, there is no assurance that they take really into
account the influence of all parameters which are not changed in the
experiments for determining the experimental constants. As already said this is