The working principle of
If the wood is made of wood, the drying of the wood can prevent the deformation of the product, the ceramic billet is dry before the calcination can prevent the finished product cracked. In addition, the dry materials are also easy to transport and store, for example, the harvested grain will be dried to a certain moisture content to prevent mildew. As the natural dryness is far from meeting the needs of production development, various mechanized drying machines have been widely used.
The amount of water vapor in the compressed air is determined by the temperature of the compressed air: in keeping the compressed air pressure is almost the same, the lower the temperature of the compressed air compressed air can be reduced by the water vapor content, and the excess of water vapor condenses into liquid. Freeze-drying machine USES this principle to use refrigeration technology to dry compressed air. Therefore, the cold drying machine has refrigeration system. Refrigeration system of freeze-drying machine belongs to compression refrigeration, consisting of four basic components, such as refrigeration compressor, condenser, evaporator and expansion valve. Between them in turn connect pipe to form a closed system, the refrigerant in the system constantly circulating, change state and heat exchange with compressed air and cooling medium. The compressed air dryer also has adsorption dryer and dissolving dryer.
The refrigeration compressor takes the low pressure (low temperature) refrigerant in the evaporator into the cylinder of the compressor, and the refrigerant vapor is compressed, and the pressure and temperature rise simultaneously. Refrigerant of high temperature high pressure steam pressure to the condenser, the condenser, higher temperature of the refrigerant vapor heat exchange with a relatively low temperature of the cooling water or air, the quantity of heat of refrigerant was taken away by water or air cooling down, refrigerant vapor into liquid. This part of the liquid is then transported to the expansion valve, which flows through the expansion valve into a low-temperature low-pressure liquid and into the evaporator; In the evaporator, the refrigerant liquid of low temperature and low pressure absorbs the heat of compressed air and vaporizes (commonly known as "evaporation"), while the compressed air is cooled and condenses a large amount of liquid water. The refrigerant vapor in the evaporator is sucked off by the compressor, so that the refrigerant can be compressed, condensed, throttling and vaporized in the system, thus completing a cycle.
In the refrigeration system of freeze-drying machine, evaporator is the equipment for conveying cold quantity. The refrigerant absorbs the heat of compressed air and realizes the purpose of dehydration and drying. The compressor is the heart, and it ACTS as an inhalation, compression, and transport refrigerant vapor. The condenser is a device that releases heat, passing the heat from the evaporator to the cooling medium (like water or air) along with the heat from the compressor's input power. The expansion valve/throttle valve ACTS as a throttle to the refrigerant, controls and regulates the amount of refrigerant liquid flowing into the evaporator, and divides the system into two parts: high voltage side and low pressure side.