Fundamental:

Scraper type rotary film evaporator is a high-efficiency evaporation and distillation equipment that uses a high-speed rotating film wiper to distribute liquid into a uniform film for evaporation or distillation. It can also perform unit operations such as deodorization, defoaming reaction, heating and cooling. It consists of one or more cylinders heated by a jacket and a film wiper rotating in the cylinder. The film wiper continuously scrapes the feed into a thin and uniform liquid film on the heating surface and moves it down. In this process, the low boiling point components are evaporated, and the residue is discharged from the bottom of the evaporator. Jiangsu Heide company design adopts centrifugal sliding grooved rotor, which is the latest foreign structure of evaporator. It can also form a thin film under the condition of small flow. The sludge in the treatment liquid attached to the inner wall of the evaporation section of the cylinder can be scraped. The plate is quickly removed, and compared with a scraper evaporator with a fixed gap, the evaporation can be increased by 40-69%. As shown below:

Main Features: 

 ● Very small pressure loss. The material stream and the secondary steam stream are two independent channels. The material falls down along the inner wall of the evaporator cylinder (which is forced to form a film), and the secondary vapor evaporated from the evaporation surface leaves the evaporator almost unimpeded from the space in the center of the cylinder, so the resistance is reduced to a minimum.

 ● High vacuum conditions. Since the resistance of the secondary steam from the evaporation surface to the condenser is very small, it can maintain a high degree of vacuum and effectively reduce the boiling point of the processed material.

 ● High heat transfer coefficient, large evaporation capacity and high thermal efficiency. The lowering of the boiling point of the material increases the temperature difference with the heating medium, and the turbulent liquid film also reduces the thermal resistance; the rotating film wiper can prevent the material from coking and scaling on the wall, and also improves the separation of the evaporation cylinder wall. Heat transfer coefficient, evaporation intensity can reach 200kg/m2·hr.

 ● Low temperature evaporation. Because the evaporation cylinder can maintain a high degree of vacuum, the boiling point of the processed material is greatly reduced, so it is especially suitable for low-temperature evaporation of heat-sensitive materials.

The material heating time is short. The residence time of the material in the evaporator is short, between about 5 seconds and 10 seconds. For the commonly used movable scraper, the rotation direction of the scraper groove can be changed to adjust the heating time of the material in the evaporator, and work under vacuum conditions, which is more beneficial to heat-sensitive materials and effectively prevents the product from being damaged during the evaporation process. Decompose, aggregate or deteriorate to ensure product quality.

 ● Low-grade steam can be used. As the boiling point of the material is reduced, the temperature of the heating medium can be lowered under the condition of ensuring the same temperature difference, and low-grade steam can be used efficiently, which is beneficial to the comprehensive utilization of energy.

 ● Adapt to a wide range of viscosity changes, both high and low viscosity materials can be processed, and the material viscosity can reach up to 100,000 centipoise (CP).

Application range:

The scraper-type rotary film evaporator designed by Jiangsu Heide company has simple structure, convenient maintenance, easy cleaning, convenient operation, easy adjustment of product indicators, and continuous production under airtight conditions. The inner wall of the evaporation section barrel is precision boring and polishing treatment, the surface is not easy to cause coking and scaling. It has been widely used in Chinese and Western pharmaceuticals, food, light industry, sugar, biological products, sewage treatment, machinery, metallurgy, petrochemical and other industries.