The evaporation of a liquid into a thin film is called thin film evaporation. The principle of thin film evaporation to accelerate evaporation is that under the condition of reduced pressure, the liquid travels through the thin film and has a large vaporized surface area. The heat spreads quickly and uniformly. Influence, can better prevent the material overheating phenomenon, thin film evaporation has the advantages of low temperature, short time, fast evaporation speed, continuous operation and shortened production cycle.
Characteristics of thin film evaporation
Low vacuum pressure drop:
The material vaporized gas is sent from the heating surface to the external condenser. There is a certain pressure difference. In general evaporators, this pressure reduction is usually relatively high, and sometimes even difficult to accept. The scraped film evaporator has The larger the gas passes through the space, the pressure in the evaporator can be regarded as almost equal to the pressure in the condenser, so the pressure drop is small and the vacuum can reach 5 mmhg.
Low operating temperature:
Due to the above characteristics, this allows the evaporation process to be maintained at a higher vacuum. Due to the increase in vacuum, the boiling point of the corresponding material is rapidly reduced. Therefore, the operation can be performed in a lower temperature environment, which reduces the Thermal decomposition of the product.
Heating period:
Due to the unique structure of the scraper type thin film evaporator, the film scraper has the function of pumping, so that the residence time of the material in the evaporator is very short. In addition, the high-speed turbulent flow of the film on the heated evaporator makes the product not stay at The surface of the evaporator is therefore particularly suitable for the evaporation of heat-sensitive materials.
High evaporation intensity:
The decrease of the boiling point of the stream increases the temperature difference with the heat medium, the function of the wiper, reduces the thickness of the film in a turbulent state, and reduces the thermal resistance. At the same time, the material is prevented from forming a knot on the heating surface during the process. Scale, and accompanied by good heat exchange, therefore, the overall heat transfer coefficient of the scraped film evaporator is improved.
Due to the unique properties of the scraper type thin film evaporator, it is related to the heat-treatment heat sensitivity and the requirements of smooth evaporation, high viscosity and highly increased viscosity with increasing concentration of the stream, the evaporation process can also be smoothly evaporated, it can also successfully It is used for the evaporation and distillation of materials containing solid particles, crystallization, polymerization, structure, etc.
View more quality glove box with low price and free shipping all over the world.
