Application of Drying Equipment in Flower Deep Processing With the rapid development of domestic economy, people's material level has been constantly improved, food, clothing and transportation have been met, but now not only satisfied with the material improvement, but also the spiritual demand is growing, for example, in the flower industry, its annual growth rate is quite rapid.These demands include not only original potted plants.Flowers are also used as processing materials in food industry and medicine industry.Next, Rihong Garter Powder Equipment Company will talk about the application of drying equipment in flower deep processing. Brief Introduction of Vacuum Freeze Drying Vacuum freeze-drying, also known as sublimation drying.The principle is to freeze the material, make the water it contains into ice, and then sublimate the ice in vacuum to achieve the purpose of drying. Like other drying methods, in order to maintain sublimation drying, two basic conditions must be satisfied, i.e. constant supply of heat and constant elimination of steam generation.In the initial stage, if the material temperature is relatively high, the latent heat required for sublimation can be derived from the sensible heat of the material itself.However, with the sublimation, the material temperature quickly drops to the temperature balanced with the vapor partial pressure in the drying chamber. At this time, if there is no external heating, the sublimation drying will stop.In the case of external heating, if the steam generated by sublimation is not removed in time, the partial pressure of the steam will rise, and the temperature of the material will also rise. When the freezing point of the material is reached, the ice crystals in the material will melt and freeze-drying will not be carried out. Application of Vacuum Freezing in Flower Production   1.Pre freezing process Pre-freezing is to freeze flowers into a certain shape by general freezing method as a separate operation before freezing and drying.In vacuum freezedrying, the higher freezing temperature of materials is an important factor affecting the quality and energy consumption of freeze-drying products.The pre-freezing temperature must be lower than the eutectic temperature. Otherwise, it will cause the surface blistering and shrinkage of the product.Generally, the lower freezing temperature of the product is lower than the eutectic temperature of 5-10 C.But the freezing temperature can not be set too low, otherwise, there will be large investment and high energy consumption. In addition, the pre-freezing rate is also an important factor affecting the drying rate and product quality.The sublimation rate is faster in slow freezing and drying time is longer in fast freezing.The suitable cooling rate should adopt a slower cooling rate on the premise that the material quality is not affected.   2.Sublimation drying process To maintain the continuous sublimation drying, two basic conditions must be met, namely, the constant supply of heat and the constant elimination of steam generation.The drying process is gradually dried from the surrounding to the inner center. The heat transfer driving force in the drying process is the temperature difference between the heat source and the sublimation interface, while the mass transfer driving force is the vapor partial pressure difference between the sublimation interface and the cold trap. The larger the temperature difference, the faster the heat transfer rate, the larger the vapor partial pressure difference, the faster the mass transfer rate. In sublimation drying, the heating temperature should not exceed the eutectic point temperature of the material. If the temperature is too high, ice crystals will melt, which will affect the quality of the product.In addition, the heating mode in sublimation drying process directly affects the material temperature distribution, sublimation interface temperature, sublimation interface vapor flux and drying time and other important process parameters.   3.Analytical drying process Analytical drying is a process of removing water in the form of free or bound water in the matrix of material after sublimation drying.Analytical drying of materials generally depends on much higher temperatures than sublimation temperatures. High temperature and low pressure are conducive to analytic drying. For example, frozen tomato slices, which can be frozen into ice structure water and a large amount of free

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