Lab small scale falling film evaporator hemp
The working principle of the laboratory falling film evaporator:
The feed pump of the falling film evaporator sends the material to be processed to the top of the heating chamber of the evaporator. After being evenly distributed by the film distributor, with its own power, the material flows vertically and uniformly from top to bottom along the inner surface of the heating tube. The steam outside the tube transfers heat to the material through convection-conduction. The secondary steam generated during the heating process of the material flows from top to bottom with the material at a fast speed in the tube. The vapor-liquid mixture flows out from the lower end of the heating tube and enters boiling. The chamber undergoes evaporative boiling, thereby completing the evaporation process.
Features of small falling film evaporator:
1. The heat transfer efficiency is high, and the heat transfer coefficient is still large under a small temperature difference.
2. No boiling point rise caused by static liquid column, short residence time of materials on heating surface, small liquid holding capacity, especially suitable for evaporation and concentration of heat-sensitive materials.
3. The material liquid passes through the heating tube once, instead of the traditional natural circulation evaporator, the material liquid circulates multiple times inside, so the product quality is good.
4. Falling film evaporation is suitable for evaporating materials with high viscosity, that is, 50~-450cp, but not suitable for handling easy-to-crystallize solutions.
5. System control accuracy: temperature ±1℃, pressure ±0.01 MPa, liquid level height 10mm. Because of the thin coat shape, the liquid flow rate is large, so the evaporation heat coefficient is correspondingly large.
6. The pressure drop is small, so the pressure on the process side of the heat exchanger is close to a constant, and the sensible heat can be used less or less.
7. Since the process fluid flows only under the action of gravity, rather than being pushed by the resistance difference, it allows the use of a more economical low resistance difference.
8. Less liquid stagnation in the equipment.
9. Boiling is convective boiling, so the surface state of the tube has little effect on boiling.
What are the components of the falling film evaporator?
The falling film evaporator consists of each effect heating evaporator, each effect separator, condenser, heat pump, sterilizer, insulation pipe, vacuum system, each effect material liquid transfer pump, condensate drainage pump, operation platform, electrical instrument control cabinet And valves, pipelines and other systems.
