Pervaporation membrane simulation

1 liquid feed -> vapor permeate + liquid retentate (breaks azeotropes)

Governing equations

The exact equations the solver works for a pervaporation membrane — the same math shown in the app's "Theory" panel, not a black box.

$J_i$

molar flux of i through the membrane [mol/s]

$Q_i$

permeance [mol/(m²·s·Pa)]

$A$

membrane area [m²]

$x_i$

liquid-side mole fraction

$y_i$

permeate vapour mole fraction

$K_i$

equilibrium ratio from the thermo package — this is how non-ideality (an azeotrope) enters, and why pervaporation can cross one

$p_{i,feed}$

feed-side partial pressure [Pa]

$P_{perm}$

permeate pressure (vacuum) [Pa]

Parameters

area [m² membrane], permeance {component: mol/(m²·s·Pa) — ratios set the selectivity, e.g. water >> ethanol for a hydrophilic dehydration membrane}, permeate_pressure [Pa vacuum, default 1000]; optional temperature [K]. Permeate leaves as vapor, retentate liquid — crosses azeotropes distillation cannot. Use an activity package (nrtl/uniquac).

Example flowsheets that use it