Gas processing Β· Distillation shortcut (FUG) Β· GPSA Β§16
Condensate Stabilizer β Fenske-Underwood-Gilliland
Distillation shortcut: minimum stages (Fenske), minimum reflux (rigorous multi-root Underwood), actual stages (Gilliland), feed stage (Kirkbride) and reboiler/condenser duties. Enter components with relative volatility Ξ± (referenced to the heavy key), and pick the light/heavy keys.
Feed Components
Name
z mol%
Ξ±
Keys & Specs
Duty Inputs
kmol/h
kJ/kmol
Engineering Basis
Fenske: Nmin = ln[(dLK/bLK)(bHK/dHK)]/ln(Ξ±LK).
Underwood: solve ALL common roots ΞΈ of Σαizi/(Ξ±iβΞΈ)=1βq in the key span, then Vmin=Σαidi/(Ξ±iβΞΈ) simultaneously (rigorous multi-root Underwood; handles distributing between-key components).
Gilliland (Eduljee) β N at R = factor Γ Rmin; Kirkbride feed stage.
Duties: Qc = (R+1)Β·DΒ·Ξ»; Qr β Qc (near-neutral feed).