The outstanding advantage of the wiped thin film evaporator is that it can be applied to the treatment of different materials, and is suitable for the evaporation of high viscosity, easy crystallization, easy scaling, suspended solids or heat sensitive liquid. The scraper film evaporator is mainly composed of a heating jacket and a scraper. The jacket is heated by steam, and the scraper is mounted on a rotatable shaft, and the scraper and the heating jacket inner wall maintain a small gap.
In actual operation, after the pre-heat treatment, the feed liquid is added from the upper part of the wiped thin film evaporator in the tangential direction, and under the action of gravity and rotating scraper, the inner spiral wall is formed on the inner wall, and is continuously lowered during the descending process. It is concentrated by evaporation, the completion liquid is discharged from the bottom, and the secondary vapor escapes from the top. In some cases, this evaporator evaporates the solution to give a solid product directly at the bottom.
The scraper film evaporator is easy to use and flexible to operate. For this reason, the device can be used to treat heat sensitive materials and materials that require smooth evaporation, high viscosity, and a sharp increase in viscosity with concentration, and the evaporation process can also evaporate smoothly. It can also be successfully applied to the evaporation and distillation of materials containing solid particles, crystallization, polymerization, scaling and the like.