vacuum dryers mechanical classification
There are many kinds of vacuum dryers. Most of the drying rooms can be closed and the atmospheric drying equipment can realize vacuum drying. In the field of vacuum drying technology, vacuum dryers can be divided into ordinary vacuum drying and special vacuum drying.
Ordinary vacuum dryers mainly include: box type drying equipment suitable for drying liquid, paste, powder and granular materials; drum type vacuum dryer suitable for drying juice, milk, molasses, sweet potato paste, tomato sauce, etc.; belt vacuum dryer suitable for orange juice, tomato juice, instant tea and instant coffee; suitable for powder granular materials, such as vitamin C, etc There are also drum stirring vacuum dryer, double cone rotary vacuum dryer, rake vacuum dryer, disc scraper vacuum dryer, etc.
Special vacuum dryers mainly include: vacuum freeze-drying equipment, low-frequency vacuum dryer and gas-phase vacuum dryer.
Mechanical classification of vacuum dryer:
1. Vacuum disc vacuum dryer
For example, vacuum drying machine can be used for medicine drying. The whole operation process was carried out under negative pressure. The wet material is added into the quantitative feeder, and the material is evenly added into the dryer through the continuous locking device for drying operation, and the dried material is discharged from the outlet at the bottom of the dryer. The moisture escaping from the material is recovered by condenser and solvent receiving tank.
2. Double cone rotary vacuum dryer
The double cone rotary vacuum dryer is suitable for the concentration, mixing and drying of powdery, granular and fibrous materials in chemical industry, pharmaceutical industry and food industry, as well as materials requiring low-temperature drying (such as biochemical products). It is more suitable for drying materials which are easy to oxidize, volatilize, strongly stimulate heat sensitivity, toxic materials and materials that are not allowed to destroy crystals.
3. Vacuum rake vacuum dryer
Vacuum rake dryer is a kind of conduction heat transfer dryer. The material does not contact with heating medium directly. It is suitable for drying a small amount of muddy and paste materials which are not resistant to high temperature and easy to oxidize. The moisture content is 15% ~ 90%.
4. Plate vacuum vacuum dryer
Plate type vacuum dryer, also known as disc vacuum dryer, is a kind of multi-layer fixed hollow heating disc (also known as loading disc), rotary rake mixing, vertical continuous conduction based drying device based on intermittent stirring conduction dryer and a series of advanced technologies.
5. Continuous vacuum dryer
The low temperature belt type continuous vacuum dryer has repeatedly compared the advantages and disadvantages of conventional spray drying and freeze-drying, and has successfully developed a completely new concept of high efficiency and energy saving drying equipment.
In the drying of products in Chinese traditional medicine, western medicine, chemical industry, food, health care products, spray drying is beneficial to the cost, but the solubility of products is not good. The shape of the original flavor and powder has bigger defects, and the products with higher viscosity and heat sensitivity are incapable of action. Conventional freeze-drying can obtain excellent solubility and high-quality products, but the output is too low and the cost is high.
The process indexes of low temperature continuous vacuum dryer are just between the above two kinds of equipment. It can form porous and loose inside the dried products, retain the original material properties of the products, and have a good appearance. Due to the vacuum low-temperature drying, it can meet the processing requirements of most thermal sensitive materials.
Low temperature continuous vacuum dryer breaks through the technical problem of continuous feeding and discharging under vacuum state, which makes the static drying successfully transformed into dynamic drying. The production of dry products is greatly increased, while the production cost is reduced.
Low temperature continuous vacuum dryer is especially suitable for drying high viscosity, high fat, high sugar and other materials which are difficult to be solved by spray drying and vacuum oven. And it can maintain the stability and consistency of product batch.