Freeze dryer is a commonly used refrigeration equipment, which achieves the purpose of drying by reducing the temperature and pressure to sublimate the moisture or other solvents in the material directly from the solid state to the gaseous state. Compared with the traditional thermal drying method, freeze drying has many advantages, such as the original structure, shape and nutrient composition of the material can be maintained, and the dried material has good rehydration. Therefore, freeze dryers have been widely used in food, medicine, biological products and other fields.
First, the working principle of the freeze dryer.
The freeze dryer is mainly composed of a refrigeration system, a vacuum system, a heating system and a control system. Its working principle is to place the material to be dried in a low-temperature, low-humidity environment, and use a vacuum pump to pump out the air to make the material in a highly vacuum state. Then, the refrigeration system starts to work, cooling the material below freezing, so that the moisture or other solvents in the material are converted directly from the solid state to the gaseous state, and are pumped out by the vacuum pump. Finally, the heating system heats the material so that the water vapor on its surface evaporates and diffuses into the surrounding air, and finally achieves the purpose of drying.
Second, the advantages of the freeze dryer.
1.Maintain the original structure, shape and nutrient composition of the material: Because freeze drying is carried out at low temperature, it will not cause thermal decomposition and deterioration of the material, so the original structure, shape and nutrient composition of the material can be well maintained.
2.The dried material has good rehydration: freeze-drying is to directly sublimate the moisture in the material into a gaseous state, so the dried material has good rehydration and can quickly return to its original state.
3.Wide range of application: The freeze dryer is suitable for a variety of materials with different properties, such as proteins, enzymes, vitamins, etc., as well as a variety of different shapes, such as granules, tablets, powders, etc.
4.Energy saving and environmental protection: The freeze dryer does not require a lot of heat energy during operation, so the energy consumption is low, and it also meets the requirements of environmental protection.
Third, the application field of freeze dryer.
1.Food industry: freeze dryers are mainly used in the food industry for the drying, preservation and processing of fruits and vegetables, meat, aquatic products and other foods. Through freeze-drying technology, the nutrients and original flavor of food can be maintained to the greatest extent.
2.Pharmaceutical industry: freeze dryers are mainly used in the pharmaceutical industry to prepare solid agents, such as granules, tablets, etc. At the same time, it is also widely used in the production of drugs that require cryopreservation such as vaccines and biological products.
3.Biological products: The application of freeze-drying technology in the field of biological products mainly involves the preservation and transportation of proteins, enzymes and other substances. Freeze-drying technology can effectively extend the shelf life of biological products and reduce their transportation costs.
4.Other fields: In addition to the above fields, freeze drying technology is also widely used in chemical, electronics, agriculture and other fields that require low-temperature drying treatment.
Fourth, the future development of freeze dryers.
With the continuous progress of science and technology and the growing demand for applications, freeze dryers will continue to develop in the future. On the one hand, with the continuous innovation and improvement of key technologies such as refrigeration technology and vacuum technology, the performance of the freeze dryer will be further improved; On the other hand, with the continuous strengthening of environmental awareness and the continuous reduction of energy consumption, the energy-saving and environmental protection performance of the freeze dryer will also be further optimized. In addition, with the continuous expansion of application fields, the application prospect of freeze dryers will be broader.
To sum up, as an important refrigeration equipment, freeze dryer has been widely used in many fields. With the continuous advancement of technology and the growing demand for applications, freeze dryers will continue to play an important role in the future.