Four ring freeze-drying experimental freeze-drying machine is common in daily life. The vacuum freeze-drying technology is abbreviated as freeze-drying , also known as sublimation air drying. Freeze-drying is a specific method of pre-freezing of aqueous materials and then sublimating them in a vacuum to obtain air-dried objects. The original biological and chemical properties of the freeze-dried objects remain basically unchanged and are easy to store for a long time. After adding water, it can return to its pre-freeze-drying form after soaking, and can maintain its original biochemical characteristics.
The four-ring freeze-drying experimental freeze-drying machine is a freeze-drying device that uses vacuum lyophilization technology to freeze-dry items, because the lyophilization time required by different products is different. In addition, are there other factors that can affect the freeze-drying time of lyophilization machine ?
First is the form and components of the material to be processed by the freeze-drying machine:
According to the shape of the freeze-drying material, it can usually be divided into solids and liquids. The form of solid and the concentration of liquid have a very great impact on the freeze-drying rate.
The next is the prefreezing rate of the freeze dryer:
The crystal size formed during freezing can greatly affect the drying rate and the dissolution rate of the product after drying. The fast freezing and slow freezing process have the following differences: the ice crystals produced by fast freezing are smaller, and the ice crystals produced by slow freezing are larger. Large ice crystals are more conducive to sublimation, while small ice crystals are not conducive to sublimation. Rapid freezing will lead to a decrease in the rate of sublimation and a fast desorption rate; slow freezing will lead to a fast sublimation rate and a slow resolution rate.
There is also a problem with loading:
When the material is freeze-dried, after being dispensed into the container, there is a certain ratio of surface area to the thickness of the substance, that is, freeze-drying is related to loading. Small surface area and thickness are conducive to moisture sublimation, easy to freeze dry and ideal quality. When drying, the wet loading amount of drying on the tray per unit area is an important factor in determining the drying time. Generally speaking, the thinner the thickness of the material accumulation, the faster the heat and mass transfer speed, and the shorter the vacuum freeze-drying time. However, if the material thickness is thin, the dry materials per batch per unit freeze-dried area is less, which is not conducive to increasing the unit freeze-dried area and output per unit time.
