Screw Evaporator
Screw Evaporator Working Principle
The scraper evaporator housing features an internal heating steam jacket, which contains rotatable blades or scrapers. There are two types of scrapers: fixed and rotor-type. The fixed ones have a gap of 0.5 to 1.5mm with the inner wall of the housing, while the gap of the rotor-type varies with the rotation speed of the rotor. The feed liquid is added to the scraper evaporator from the top along the tangent direction (or added to a spinner disc coaxial with the scraper). Due to gravity, centrifugal force, and the scraping action of the rotating blades, a downward spiraling film forms on the inner wall of the vessel, which is evaporated and concentrated during this process. The liquid then drains out from the bottom. This type of evaporator is a single-pass evaporator that uses external power to form the film.
Screw evaporator features
1. The scraper evaporator boasts high efficiency and capacity, capable of evaporating 100-300 Kg/h of solutions such as water and organic solvents.
2. The scraped surface heat exchanger has a short residence time for the treated material on the evaporation surface, approximately ±10 seconds, and does not clog or scale.
3. Scraped Film Evaporators enable low-temperature evaporation under vacuum conditions.
4. The scraper evaporator is suitable for continuous production, offering great operational flexibility, simple structure, ease of maintenance, and can be implemented with automatic control.
5. The scraper evaporator adjusts the tilt angle of the groove on the outer side of the scraper, which can regulate the residence time of the material inside the evaporator to accommodate the evaporation needs of materials with different viscosities.
6. Scraped-tower evaporators and all parts in contact with the liquid material are made of stainless steel to ensure the material remains uncontaminated.
7. The scraper evaporator is equipped with a quick-release cover on top for easy cleaning of the heating tubes. Light holes and a viewing mirror are installed on both sides of the top for convenient observation during operation.
Screw Evaporator Application Scope
Screw evaporators are used in the oil and chemical industries, suitable for high-viscosity materials (such as gum, honey, etc.) and those prone to crystallization, scaling, and heat sensitivity.
