Unit operations Distillation

If pressure increases then the quantity of distillate get less and if we decrease the pressure then the quantity of vapor increases but if the difference in boiling point is less than bottom product also goes to distillate and we get impure product

The higher the pressure the lower the cooling rate

If we increase the pressure, the no. of stages in a distillation column becomes less as the liquid boils earlier (boiling occurs when the atmospheric pressure becomes equal to the vapour pressure of the liquid.)