Use for L'min 0.14 0.13 -Equilibrium Line 0.12 0.11 0.1 0.09 0.08 Y (mol C/mol A) 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 0 0.0005 0.001 0.0015 0.002 0.0025 0.003 X (mol C/mol MEA-W) Use for N 0.12 -Equilibrium Line 0.11 0.1 0.09 0.08 0.07 Y (mol C/mol A) 0.06 0.05 0.04 0.03 0.02 0.01 0 0 0.0002 0.0004 0.0006 0.0008 0.001 0.0012 0.0014 0.0016 0.0018 0.002 X (mol C/mol MEA-W)

Carbon dioxide (CO2) is a greenhouse gas that must be removed from coal-fired power plant
exhaust before the exhaust can be discharged to the outside air. 150 mol/h of a gas stream containing
10 mol% CO2 [C] and 90 mol% air [A] is contacted with a pure mixture of monoethanolamine (MEA)
and water [MEA-W] (assume the MEA-W mixture is one component) at 40 °C and 10 atm in an
absorption column. It is desired to remove 92 mol% of CO2 from the air. L’/L’min is 1.45. Assume
solute free flow rates are constant, which means the MEA-water mixture is nonvolatile and air does
not dissolve in the MEA-water mixture. Assume the column is isothermal at 40 °C and isobaric at 10
atm. Graphs needed are provided at the end of this document.
a) Draw a PFD and label using solute free flowrates and mole ratios
b) Determine the minimum liquid solvent flowrate required (L’min)
c) Determine the equation of the operating line
d) How many stages (N) are required to get the desired separation?