Why the Total Heat Transfer Coefficient of the Scraper Membrane Evaporator is Higher

The刮板薄膜蒸发器 comes in two types: fixed scraper and movable scraper, and is further categorized into vertical and horizontal installations; with the vertical type being divided into falling film and rising film configurations. It is 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 inlet, or is evenly distributed around the inner wall by the liquid distribution disk fixed on the rotating shaft inside the evaporator. Due to the action of gravity and the centrifugal force of the scraper, the liquid forms a spiral descending or ascending film on the inner wall, or a film that spirals forward. The secondary steam is condensed and discharged into the condenser after passing through the vapor-liquid separator at the top or the concentrated liquid outlet. Since the liquid remains in a film state during concentration and is continuously renewed, the scraper film evaporator has a high overall heat transfer coefficient, making it suitable for concentrating low-viscosity juices, honey, milk, or liquid containing suspended particles.
The scraper film evaporator is a novel evaporator that, through the forced formation of a film by rotating scrapers, allows for film evaporation under vacuum conditions. It boasts a high heat transfer coefficient, high evaporation intensity, short flow time, and large operational flexibility, making it suitable for the concentration, degassing, desolvation, and purification of heat-sensitive materials, high-viscosity materials, and materials prone to crystallization containing particles.