Distillation: Summary Distillation is a widely used separation process The separation is based on the volatility difference of the components to be separated
Distillation : Summary • Distillation is a widely used separation process. • The separation is based on the volatility difference of the components to be separated
Wide application of distillation WHY? Volatility difference exists for most mixtures Only heat is needed for the separation, no other extra agents are needed So the products may be pure
Wide application of distillation: WHY? • Volatility difference exists for most mixtures. • Only heat is needed for the separation, no other extra agents are needed. So the products may be pure
Classification of distillation Relative volatility Process Example big Equilibrium H, and oil distillation or flash distillation medium Benzene fractionation and tolune small azeotropic Absolute distillation and thanol extractive distillation D production
Classification of distillation Relative Volatility Process Example big Equilibrium distillation or flash distillation H2 and oil medium fractionation Benzene and tolune small Azeotropic distillation and extractive distillation Absolute ethanol production 1 2 3 4
Flash distillation dew point line bubble point line XAOI JA
Flash distillation T xAor yA dew point line bubble point line
Fractionation with rectifying section and stripping section column with rectifying section and stripping section condenser(total and partial), accumulator cooler cold water reflux and overhead product reboiler: steam and condensate bottom product
Fractionation with rectifying section and stripping section • column with rectifying section and stripping section • condenser(total and partial), accumulator, cooler: cold water • reflux and overhead product • reboiler: steam and condensate • bottom product
Equipment to implement distillation process Plate tower or column Packed tower or column
Equipment to implement distillation process • Plate tower or column • Packed tower or column
Structure of plate tower sieve plate; perforations downcomer weir
Structure of plate tower • sieve plate; • perforations; • downcomer; • weir
Calculation of distillation process minimum reflux ratio minimum number of trays optimum reflux ratio and number of plates
Calculation of distillation process • minimum reflux ratio • minimum number of trays • optimum reflux ratio and number of plates
McCabe-Thiele method for the calculation of theoretical tray number equilibrium stage assuption (ideal stage) constant molar overflow assumption operating line and equilibrium curve feed line
McCabe-Thiele method for the calculation of theoretical tray number • equilibrium stage assuption (ideal stage) • constant molar overflow assumption • operating line and equilibrium curve • feed line