STABILITY CALCULATIONS FOR NONEQUILIBRIUM SEPARATION PROCESSES

Two of the most significant contributions in the last two decades to s eparation process are the numerical implementation of the tangent-plan e criterion to check the stability of any given mixture and the use of mass-transfer models to solve separation;process problems. This work combines the use of the tangent-plane analysis with mass-transfer mode ls to solve problems with multiple liquid phases. As in equilibrium-st age problems, the tangent-plane analysis works effectively with nonequ ilibrium-stage separation-process problems. An example is presented wh ere the nonequilibrium model, when used in conjunction with the tangen t-plane criterion, predicts the correct number of phases, while the eq uilibrium model predicts the incorrect number of phases.