Extraction Flash Calculation - 4 Component and 2 Phase System

[Dario56]

I am performing extraction flash calculations for 4 component and 2 phase system. For anyone somewhat shaky with what extraction flash calculation is; extraction is performed, feed composition is known and we are calculating compositions of both phases at equilibrium, mole fraction of every component in both phases as well as mole fraction of both phases.

This calculation is done numerically, until convergence criterion is satisfied. I know it is possible to take calculated mole fraction difference in two consecutive iterations as a convergence criterion, but I am not sure how many criteria I should apply in case of 4 component and 2 phase system?

I am thinking I need to apply 3 such criteria for 3 components in the system for one of the phases because mole fraction of 4th component is satisfied automatically by mass balance for the phase and mole fractions of components in other phase is satisfied automatically by phase equilibrium condition or mass balance for every component.

I am not sure if this is correct?

 

[Lnewqban]

Is the extraction flash continuous?

 

[Chestermiller]

In my judgment, the approach you recommended is fine.