Where L/V is the ratio of liquid to vapor.Ĭomparing the numerator and denominator with the two. Then the mass balances before and after separation are L = the moles of liquid of composition xB zF is not equal to either x or y, but x and y be determined from the T vs. If zF is in the two-phase region, the system will separate into a liquid and vapor of new mole fractions x and y, respectively.
If zF is a saturated vapor, zF is essentially yF with a single liquid drop formed of new mole fraction x. If zF is a saturated liquid, zF is essentially xF with a single vapor bubble formed of new mole fraction y. If zF is a superheated vapor, zF is yF and there is no x.
If zF is a subcooled liquid, then zF is simply xF and there is no y. The feed phase is dependent upon the temperature, pressure, and the composition (mole fraction).Īssuming that the equilibrium stage is at the same temperature and pressure of the feed: Mixture, a saturated vapor, or a superheated vapor. Note that a feed mole-fraction, zF,can be a subcooled liquid, a saturated liquid, a two-phase 圎tOH is the mole fraction of ethanol in the liquid stream. yEtOH is the mole fraction of ethanol in the vapor stream. zEtOH is the mole fraction of ethanol in the feed. L is the total moles in the liquid stream exiting the stage. V is the total moles in the vapor stream exiting the stage. Single Equilibrium Stage Ethanol-Water, P = 1 atmį is the total moles of ethanol and water fed to the stage.
Distillation Equilibrium (Review) Flash Distillation Multistage Distillation