Agitated Thin Film Evaporator

Agitated thin film evaporator (also commonly referred to as a "Thin Film or wiped film evaporator") consists of two main parts: a cylindrical jacketed body which is heated by means of steam or thermic fluid and a rotor inside the cylindrical tube. Product is introduced above the heated zone on a distributor plate. This distributor plate evenly transfers the liquid over the evaporator's inner surface. As the product spirals down the wall, the high rotor tip speed generates centrifugal force and due to low clearance between rotor blades and cylinder inner surface, it creates thin film. This thin film and heated surface create optimum heat flux and mass transfer conditions. Volatile components are rapidly evaporated via conductive heat transfer. Vapours flow either counter-currently or co-currently through the unit, depending on the application requirements. The vapours are passed through condenser and collected. Residual components are discharged at the outlet. Continuous agitation and mixing by the rotor blades minimizes fouling of the thermal wall where the product or residue is most concentrated. Advantages are less residence time, can handle heat sensitive materials and lesser space requirement.