Vacuum freeze dryer
Vacuum freeze dryer is abbreviated as freeze dryer, which is industrial freeze drying equipment for sublimation. It has been widely used by the manufacturer, in the freeze drying fields of injection, protein, bacteria or other pharmaceutical area.
Nowadays, the food vacuum freeze dryer is developing rapidly, including processing fruit, vegetable and coffee. As the name implies, the vacuum freeze dryer for sale has both vacuum system and refrigeration system. At the same time, it also needs heating system to provide the required heat for product sublimation. Since the internal space of the main body of the vacuum freeze dryer is in a vacuum state during operation, a pressure difference of -0.1Mpa is formed with the outside atmospheric pressure. Therefore, the vacuum freeze dryer is a negative pressure container. In order to enable the vacuum freeze dryer to withstand the pressure difference, generally speaking, the container is designed in a cylindrical shape to maximize its compressive strength. If a rectangular design is adopted, reinforcing ribs must be used on the outside of the rectangular warehouse body to ensure its compressive strength.
There are many drying methods, such as sun drying, hot air drying, spray drying and vacuum drying, but traditional drying methods are usually carried out at temperatures above 0°C or higher. The dried products generally have the problems of reduced volume and hard texture. Most of the volatile components will be lost. Some heat-sensitive materials will be denatured and deactivated, and some materials may be oxidized. Therefore, there is a big difference in the properties of the dried product compared to the one before drying. The process of vacuum freeze dryer is basically carried out below 0°C, that is, the product is carried out in a frozen state, and generally does not exceed 60°C during drying. Under vacuum conditions, when the water vapor is directly sublimated, the product remains in the frozen ice status, forming a sponge-like loose porous structure, so its volume is almost unchanged after processed by vacuum freezer dryer.
According to the production capacity, there are laboratory vacuum freeze dryer and industrial vacuum freeze dryer. The laboratory freeze dryer requires complete functions, low noise, and can use single phase power. The industrial freeze dryer requires large output capacity, high production efficiency, energy saving and environmental protection.