The vacuum dryer is composed of a refrigeration system, a vacuum system, a heating system, and an electrical instrument control system. The main components are drying oven, condenser, refrigeration unit, vacuum pump, heating/cooling device, etc. Its working principle is to freeze the item to be dried to below the triple point temperature, and then directly sublimate the solid water (ice) in the item into water vapor under vacuum conditions, and then remove it from the item to make the item dry.
After pre-treatment, the material is sent to the quick-freezing bin to freeze, then sent to the drying bin for sublimation and dehydration, and then packed in the post-processing workshop. The vacuum system establishes a low-pressure condition for the sublimation drying chamber, the heating system provides sublimation latent heat to the material, and the refrigeration system provides the required cooling capacity to the cold trap and drying chamber.
The equipment adopts radiation heating, and the material is heated evenly; it adopts a water trap, and can realize rapid defrosting; it adopts a vacuum unit, and can realize oil-water separation; ;Adopt artificial intelligence control, high control precision, easy operation.
The quality requirements for freeze-dried products are: unchanged biological activity, uniform appearance and color, full shape, firm structure, fast dissolution rate, and low residual moisture. To obtain high-quality products, one should have an understanding of the theory and process of freeze-drying.