Page 139 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

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T is the absolute temperature of the liquid phase in K, and ju - the ionic strength
of the solution. In our case ju can be calculated by the equation:

(56)

where C t is the ion concentration and Zt is its valence.
In case of absorption of CO2 in NaOH solution:

+
CcNa2COS r (57)

where Cmm and C Na3coi are the molar concentrations of NaOH and Na2
The effective surface area can be calculated as follows:
1. The flow rate of the absorbed CO2 (Go) is calculated from the mass
balance

GG= [V G C Gin- (V G C G(J (l-C Gln)f(l-C GcJ]/22.4, mol/s 5 (58)

where V G is the inlet flow rate of the gas in the column in nm'/s;
C Gin and Ccout - the inlet and outlet concentrations of the carbon dioxide in the
3
3
3
gas phase in nm /nm ; 22.4- the volume of 1 mol gas in nm /mol.
2. The volumetric mass transfer coefficient ^ar is determined by the
equation:
(59)

1
where K^a is the volumetric mass transfer coefficient in s" ;
H- packing height- m;

is the logarithmic average concentration difference of CO 2 in the gas phase,
3
mol/m ;
3
C Gmk and Caoutk- inlet and outlet CO2 concentrations in the gas phase, mol/m ;