Page 43 - Packed bed columns for absorption, desorption, rectification and direct heat transfer
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38
(118)
m =
where Mi and M G are the mol mass of the liquid phase and of the gas phase in
kg/mol;
R- universal gas constant;
T- temperature in K;
3
pir liquid density in kg/m ;
P- pressure in bar.
The vapour - liquid equilibrium (in case of rectification) for a two
component ideal mixture can be calculated using the simple Raul equation,
equivalent to Henry's law. According to this equation:
PA=PA*A- (120)
where PA is the partial pressure of the component A at a given temperature in
bar;
P A - equilibrium pressure of the pure component A at the same temperature in
bar.
The same equation can be written for the other component of the
mixture (B),
p B = P B.X B (121)
Taking into account that:
X A+X B=1 (122)
and that the pressure P is a sum of p^ andpa, from equations (114) and (120) to
(122) it can be easy obtained:
