Falling film evaporator principle
In industrial field, there are always some substances which need to be extracted or concentrated. Therefore, there are also so many devices or techniques for achieving the extraction or concentration of substances.
Falling film evaporator is one of the concentrating devices, which is to separate heat sensitive substances through their different boiling points.
Falling film evaporator is a evaporation device, which has has high heat transfer efficiency, small temperature difference loss, short material residence time, no deterioration, low pressure drop, easy operation, low energy consumption, small equipment size, etc. Falling film evaporator is often used for solutions with high evaporation concentration and viscosity. It is widely used in chemical, pharmaceutical, light industry, food, petrochemical, metallurgical, pharmaceutical and other industries.
How does a falling film evaporator work
Falling film evaporator separates heat sensitive substances by their different boiling points. So how falling film evaporator gets different substances evaporated and collects them efficiently is very essential for users to know, so next let’s go through the working procedures of falling film evaporator together:
1. In the beginning of falling film evaporator’s working , the raw material liquid is added from the top of the falling-film evaporator heating chamber, distributed evenly to each heat exchange tube by the liquid distributor and film forming device at the end of the tube.
2. Under the influence of gravity, vacuum induction and airflow of the solution itself, the solution forms uniform film flow from top to bottom along the inner wall of the tube.
3. In the process of flow, steam is heated and vaporized by the shell process heating medium, and the steam and liquid phase enter the separation chamber of the evaporator together.
4. After fully separating the gas and liquid, the steam enters the condenser for condensation (single effect operation) or enters the next effect evaporator as the heating medium, thus achieving multi-effect operation, and the liquid phase is discharged from the separation chamber.A liquid distributor is installed at the top of the heating tube to make the liquid film.