Practical application of vacuum pump in vacuum drying
Vacuum pump is widely used in the process of vacuum drying, vacuum drying is a kind of the material under negative pressure condition, and appropriately by heating to the boiling point of negative pressure condition or by lowering the material after solidification by melting point, dry material drying method.
Under negative pressure condition melting point of water material in boiling point and decreased with the increase of vacuum degree, at the same time complementary with vacuum pump clearance wetted to reduce the water vapor content, make the material in the inland waters such as the solution to get enough kinetic energy from the material surface. Vacuum drying part because under a state of negative pressure isolation air makes easy oxidation and chemical changes in the process of drying materials keep the original features better, also can better by means of vacuum after injection of inert gas protection materials. Common vacuum drying equipment: vacuum drying oven, continuous vacuum drying equipment, etc.
Vacuum drying is the process of drying materials placed in airtight dry indoor, use a vacuum system of vacuum and heating the material to be dry, internal moisture of material or poor concentration diffusion to the surface by pressure difference, the kinetic energy of water molecules on the surface of material gain enough, after the mutual attraction between the molecules, escape to the vacuum chamber of low voltage space, which is the process of vacuum pumping away.
In the process of vacuum drying, the drying chamber pressure is always lower than the atmospheric pressure, less number of gas molecules, low density, low oxygen content, and therefore easy to dry the oxidation of the material, inflammable and explosive dangerous goods, etc. Sterilization of drugs, food and biological products can reduce the chance of material contamination and inhibit the growth of certain bacteria.
Because the temperature of water is proportional to the vapor pressure during the vaporization process, the moisture in the material when the vacuum is dry can be vaporized at low temperature and can be dry at low temperature. This is beneficial for the drying of heat-sensitive materials in certain drugs, foods and agricultural products.