Description:
Evaporation deals with the concentration of a non-volatile solute from a solution by the removal of required amount of volatile solvent.
Usually the solvent is water. By vaporizing a part of the solvent, useful product i.e. the concentrated solution or thick liquor is produced and the vapour is discarded. Long tube evaporators are usually used for the concentration of foamy liquids. It is a short tube vertical evaporator; the tubes are surrounded by a Stainless Steel jacket and fitted with accumulator.
Dilute solution is feed to evaporator and heated by Steam from a steam generator to concentrate the dilute feed solution to a desired level. The jacket is fitted with a steam trap and the condensate is collected at the end of trap. The vapours of volatile solvent are condensed in a shell & tube type condenser and the balance non-volatile solute collected in the accuI1mlator is recycled through the evaporator.