Application range and working process of wiped thin film evaporator

      The wiped thin film evaporator is suitable for applications where a moderate or low boiling distillate occupies a significant proportion. A medium vacuum (up to 0.1 torr, ie mm Hg) and a large surface area external condenser are used. Many applications require more than one pass through the distiller, so turnkey pilot or production equipment can achieve optimal process conditions. It is common to combine two or more distillers for continuous operation, typically a wiped film evaporator (WFE) followed by a molecular distiller. Another device configuration is a hybrid distiller that is suitable for heat sensitive materials with near boiling points. Combine the WFE (squeegee evaporator) with the rectification column. For a detailed description of this configuration, please click on its link.
The working process of the wiped thin film evaporator:
    The feed liquid enters the distiller under vacuum, and the rotation of the squeegee is rapidly spread into a film on the inner wall, and the downward movement is in full contact with the evaporation surface, and the heated wall (orange portion) and the high vacuum (yellow portion) are driven. The more volatile component (distillate) collects on the surface of the built-in condenser that is close to the distance, while the less volatile component (residue) continues to move down the inner wall of the distillation column and is collected, and the separated distillate passes. A separate discharge port flows out. Depending on the application, the desired product will be distillate or residue. The compressible low molecular weight component is collected in the cold trap of the upstream portion of the vacuum system. In order to achieve high solvent loading, an external condenser can also be provided, which can be installed directly in the downstream part of the distiller. With the cooperation of an external condenser, this can be a typical "squeegee evaporator", that is, the structure of a WFE or wiped film evaporator.