Page 90 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

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MOG and M ai- average mol mass of the gas and of the liquid phase in kg/kmol.
m = He/P - equilibrium constant;
m c- equilibrium coefficient given with the equation m e= C G I C £ ;
3
N- number of kmols in 1 m liquid and number of absorbed components;
N A- mass flux of substance A, transferred for unit of time trough unit of
2 2
interface in kg/(m s) or kmol/(m s);
Ndm - average mol flux of the component A, kmol/m .s;
Ne- criterion of Newton;
X ~X
NTfJ m = — — - overall number of mass transfer units defined with the

concentration in the liquid phase;

- overall number of mass transfer units for the gas phase;

NTP- number of theoretical stages (theoretical plates);
Y —Y
NTU fe = — — - number of mass transfer units for one theoretical stage

for the gas phase;
=
2
'xc — T^7—~ number of mass transfer units for one theoretical stage
for the liquid phase;
P- pressure, Pa, bar:
P A -equilibrium pressure of the pure component A, Pa, bar;
Pg -equilibrium pressure of the pure component B, Pa, bar;
p A - equilibrium partial pressure of absorbed component A, Pa, bar;
p B - equilibrium partial pressure of absorbed component B, Pa, bar,

= p -Peclet number for the gas phase;
Pe G — Bo G
aH e(l-H d).a.D G

Pe L = Bo L = r - Peclet number for the liquid phase;
aH H d.a.D L
z
Q- transferred heat, J, or heat flux, J/m s;
q - the heat of absorption in J/kmol;
R- universal gas constant;
Re G = °" h G - Reynolds number for the gas phase;