With the development of the industry, the drying requirements for raw materials are also required, and most of the atmospheric drying apparatuses using closed and nearly closed type are designed as vacuum dryers. The vacuum dryer has the characteristics of low drying temperature, large drying rate, energy saving, and equipment closed pollution, so it can be applied in various industries.
1. Drying of the vacuum dryer can harden the surface of the product which is easy to produce under normal pressure and dry conditions. Atmospheric hot air drying Because the vaporized water vaporizes diffuse into the air through the boundary layer of the object, local dry cracking occurs on the surface of the dry object, which forms surface hardening and affects the molding quality of the product. The pressure difference between the vacuum drying material and the surface is large, and under the action of the pressure gradient, the moisture quickly moves to the surface without surface hardening.
2. The drying system of the vacuum dryer can achieve low temperature drying. Water is proportional to temperature and pressure during vaporization. Therefore, low-temperature drying can be achieved at low pressure, which is dry for food and agricultural by-products.
3. Drying of the vacuum dryer can be. Vacuum dryers use vacuum gas. Most of the air can be pumped away with the air, and some of the rest will die or lack vitality.
4, vacuum dryer is easy to achieve product diversification, taking food drying as an example, you can control the degree of vacuum, so that the product foam, produce crisp, instant and other foods.
5. The vacuum dryer can recover the moisture at a low temperature, which is a dry recovery solvent for the solvent-containing material.
6. Vacuum drying has a series of advantages such as low drying temperature, relative humidity in the drying chamber, fat oxidation and browning, and is suitable for drying of hot food materials.
Vacuum dryer equipment costs, drying costs are relatively low, with many applications, is an important production equipment in the plastic food industry.www.srchemicalequipment.com