Why the Total Heat Transfer Coefficient of the Screw Film Evaporator is Higher

Screw plate film evaporators come in two types: fixed scraper and movable scraper, and are further classified into vertical and horizontal installations; with vertical types divided into falling film and rising film designs. They are primarily composed of a rotating shaft, feed liquid distribution plate, scraper, bearings, shaft seal, evaporator chamber, and jacketed heating chamber.
The liquid enters the evaporator along the tangent direction from the feed port, or is evenly distributed around the inner wall through a liquid distribution disk fixed on the rotating shaft inside the vessel. Due to the combined action of gravity and the centrifugal force from the scraper blades, the liquid forms a spiral descending or ascending film on the inner wall, or a film spiraling forward. The secondary steam is condensed and discharged into the condenser after passing through a vapor-liquid separator at the top or the concentrate outlet end. Since the liquid forms a film during concentration and is continuously renewed, the刮板薄膜 evaporator boasts a high overall heat transfer coefficient, making it suitable for concentrating low-viscosity liquids such as fruit juices, honey, milk, or liquids containing suspended particles.
The刮板薄膜蒸发器is a novel evaporator that uses rotating blades to force the formation of a film for evaporation under vacuum conditions. It boasts a high heat transfer coefficient, high evaporation intensity, short flow time, and great operational flexibility, making it suitable for the concentration, degassing, desolvation, and purification of heat-sensitive materials, high-viscosity materials, and materials with crystallizable particles.