Freeze drying is the removal of ice or other frozen solvents from a material through the process of sublimation and the removal of bound water molecules through the process of desorption....
The vacuum freeze dryer is an excellent drying method. Under dry conditions, the dry product can be stored for a long time without the need of additives at normal temperature. The structure of the freeze-dried product is porous and crisp, and the rehydration is fast when used. The color, fragrance, taste, shape and activity of the articles after rehydration are basically unchanged, and the vacuum freeze dryer is especially suitable for the food, health care products and pharmaceutical industries. The vacuum freeze dryer freezes the wet material or solution to a solid state at a lower temperature (-10 ° C ~ -50 ° C), and then directly sublimes the moisture into a gaseous state without a liquid under vacuum (1.3 to 13 Pa). The drying technique that ultimately dehydrates the material. ...
Freeze dryer application range:
Food industry: Freeze dryers are often used for drying fruits and vegetables, meat and poultry, aquatic products, condiments, convenience foods and specialty products. Therefore, freeze dryers are also known as food freeze dryers to maintain the original color, aroma, taste and shape of food. The purpose of the freshness is unchanged, and the rehydration is good, the finished product is easy to store and transport, the cost is reduced, and the storage period is prolonged.
Medicinal health: in the drying of royal jelly, ginseng, turtles, cockroaches, cockroaches and other nutraceuticals, vacuum freeze-drying process, better preserve the original nutritional value, and make people believe that the nutritional products are pure and natural.
Pharmaceutical industry: used for dehydration and preservation of Chinese and Western medicines such as serum, plasma, vaccines, enzymes, antibiotics, and hormones.
Biological research: The long-term preservation of blood, bacteria, arteries, bones, skin, cornea, nerve tissue and various organs using vacuum freeze-drying technology can be regenerated only by supplying water during use, and still maintain its physical properties....
The pilot freeze dryer is mainly composed of control system, vacuum system, refrigeration system and circulation system: in addition to the above components, the medicinal pilot freeze dryer has hydraulic system, in-place cleaning system and in-situ sterilization system. The medicinal flash dryer is the key equipment in the production process of the aseptic freeze-dried preparation. Due to the particularity of the medicine, the relevant departments have clearly defined the material and performance of the pilot freeze dryer. Although the current pilot freeze dryer has met the production requirements, it still has the following shortcomings in terms of economic benefits, product quality, production operation, etc. The most important point is that the vacuum is too high, which is not conducive to product sublimation! During the freeze-drying process of the product, the degree of vacuum in the environment has a direct influence on the length of the freeze-drying cycle. If the degree of vacuum is too low, the sublimation rate will drop significantly; if the degree of vacuum is too high, the heat convection will be too poor, and the freeze-drying rate will be significantly reduced....
1. Shape processing and concentration adjustment of materials
For solid materials, if there is no excessive shape requirement, the heat transfer mass transfer area can be increased by cutting treatment, thereby speeding up the freeze-drying rate and reducing the freeze-drying time; if the shape of the material is high, cutting is not allowed, and puncture can be taken. The treatment is to facilitate the escape of water vapor inside the material, and the lyophilization rate is enhanced by strengthening the mass transfer process....
