Page 149 - Packed bed columns for absorption, desorption, rectification and direct heat transfer
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a e- effective specific surface area of the packing, m /m ;
Bo c- Bodenstein number for the measuring cell.
BOQ- Bodenstein number for the gas phase;
rrj
Bo L = r - Bodenstein number for the liquid phase;
H d.D L
3
C G1 and C Gr the initial and end concentrations of the absorbed gas in mol/m ;
COH- concentration of OH ions;
3
C Li and Cu - the initial and end concentration of CO2 in the water in kmol/m ;
C\t)- concentration (or conductivity) of the tracer after the packing as a
function of the time t measured from the moment of feeding of the tracer in
form of a S function;
C E - conductivity of the liquid without tracer, S/m;
2
D- diffusivity of the absorbed component, CQ2, in the liquid phase, m /s;
2
D L - axial mixing coefficient, m /s;
2
D c - axial mixing coefficient in the measurement cell, m /s;
d- diameter of the orifices in m;.
2
g- gravity constant, m/s ;
H- packing height, m;
H c~ pressure drop as a column of liquid in m;
Ha- liquid holdup;
I o and I- gamma-ray passing through a medium, before and after the absorption
of the radiation flux by the medium, counts/s;
H ae - end effect in the measurement of the liquid holdup;
Kca- volumetric mass transfer coefficient for the gas phase -1/s;
k? - mass transfer coefficient in absorption controlled by a first or pseudo-first
order fast chemical reaction, in m/s;
k L - liquid-side controlled mass transfer coefficient, m/s;
kc - gas-side controlled mass transfer coefficient, m/s;
3 2
L- liquid superficial velocity, m /(m s);
/- length of the attenuating medium, m;
4- the way of the liquid phase in the measurement cell in m;
m- equilibrium constant of the absorption process, not accounting for the
chemical reaction;
2
Nj~ number of drip points per m ;
P a- atmospheric pressure, bar;
PQ- normal pressure, bar;
Pea- Peclet number for the gas phase;