Page 91 - Packed bed columns for absorption, desorption, rectification and direct heat transfer

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Re, = Reynolds number for the liquid phase;
a.v L
r - evaporation heat- J/kg.
Sc G = —— - Schmidt number for the gas phase;
D G

Sc L = —— - Sehmidt number for the liquid phase;

k d
G h
Sh G = - Sherwood number for the gas phase;
A?
Sh L = —-— Sherwood number for the liquid phase;

1
s- rate of renewal of the interface, i.e, the part of the surface renewed, s" ;
T- absolute temperature in K;
t- temperature, °C;
t G - temperature of the gas, °C;

t t - temperature of the liquid phase, °C;
Uh - bubble velocity in equation (148), m/§;
UL- liquid velocity in equation (149 ), m/s;
3
V- volume and gas volume in m ;
3
V p- packing volume in m ;
w- real gas velocity (flow velocity), m/s;
w<r superficial gas velocity related to the whole column cross-section, m/s;
w m - inert gas velocity related to the whole cross-section of the apparatus in
3 2
nm /(m s);
X e- initial concentration of the absorbed component in the liquid phase,
kmol/kmol;
x- coordinate in m;
x A - concentration of the component A in the liquid phase, kmol gas per kmol
liquid;
Xh - humidity of the gas related to the dry gas, kg/kg dry gas;
Y- concentration of the gas phase in kmol/kmol.
Y/r concentration of the component A in the gas phase, kmol/kmol;
F e - initial concentration of the absorbed component in the gas phase ,
kmol/kmol;
Y A- equilibrium concentration of the component A in the gas phase,
kmol/kmol;