Application of vacuum dryer in pharmaceutical and plastic industry

Double cone rotary vacuum dryer is a new type of energy application equipment which combines energy technology and vacuum technology It has a series of advantages of vacuum drying and overcomes the disadvantages of long cycle and low efficiency of conventional vacuum drying In the process of general material drying, the work efficiency can be increased by 4-10 times than that of conventional method The utility model has the advantages of high drying yield, good quality and low processing cost 　　 Double cone rotary vacuum dryer is a high-tech product integrating electronics, vacuum science, mechanics, thermodynamics, program control and other disciplines It is developed on the basis of in-depth research on seven advantages of microwave vacuum drying equipment for substances, theoretical changes, internal and external heat and mass exchange, and water transfer under vacuum conditions New technology, new process 　　 In large-scale industrial production, there are many items that can't be dried under the characteristics of high-temperature bar vacuum rake dryer For example, the application of a conduction heat transfer vacuum dryer in the pharmaceutical industry of some drugs, chemicals, nutritious food, ginseng, pilose antler and other Chinese herbal medicines In order to ensure the quality of products, the drying treatment must be under the condition of less than 100 ℃ or room temperature As we all know, the boiling point of water is also reduced For example, at one atmospheric pressure (101.3kPa), the boiling point of water is 100 ℃, while at 0.073 atmospheric pressure (7.37kpa), the boiling point of water is 40 ℃ Under vacuum condition, the water inside the object can be evaporated without heating Because of the difficulty of air convection and heat transfer under vacuum condition, only relying on the way of heat conduction to provide thermal energy for materials, the vacuum dryer is facing the key of integrated upgrading technology management The conventional vacuum drying method is slow in heat transfer, low in efficiency and difficult in temperature control The vacuum box dryer introduces that heat is a kind of radiation heating, which directly affects the material, so that it is heated inside and outside at the same time, without convection or conduction to transfer heat, so the heating speed is fast, the drying efficiency is high, and the temperature control is easy In the 1980s, the developed countries began to develop the industrial double cone rotary vacuum dryer, and achieved good results in practical application Vacuum dryer has also entered the field of plastic processing For example, the vacuum dryer developed by American company has been applied to plastic processing This continuously operated machine consists of three cavities mounted on a rotating conveyor belt At the * cavity, when the colloidal particles are filled, a gas heated to a drying temperature is introduced to heat the colloidal particles At the gas outlet, when the material reaches the drying temperature, it is moved to the second cavity which is vacuumized Because the vacuum reduces the boiling point of water, it is easier for water to become water vapor and be evaporated, so the water diffusion process is accelerated Because of the vacuum, there is a greater pressure difference between the inside of the particles and the surrounding air In general, the residence time of the material in the second chamber is 20min-40min, while for some materials with strong moisture absorption, Zui needs to stay for 60min more After Zui, the material is sent to the third chamber and thus removed from the dryer.