What is the use of liquid nitrogen in freeze dryer?
Drying is a very old operation, but heating and drying of powders and biological products often leads to irreversible agglomeration of the particles, especially in the preparation of ultrafine powders, in which the nanoparticles in the liquid phase are dried and aggregated into agglomerates that are difficult to disperse. Esters are mainly because water is dispersed in the pores between the particles during the ordinary drying process. The surface tension causes an extremely high additional pressure and compacts the particles together to form a mass.
Freeze drying can avoid this problem. Freeze-drying is to freeze the gel or blood into a solid, then vaporize and remove water under reasonable conditions by sublimation, because the vaporization process of ice does not affect the coalescence of solid particles, so it can be well preserved. . The particles are not compressed and agglomerated. In addition, freeze-drying is very suitable for the treatment of biological products, such as blood, because it does not operate at high temperatures and can prevent deterioration of biological products.
Application of liquid nitrogen in small freeze dryers:
Liquid nitrogen freeze-drying is one of the most widely used freeze-drying equipment in the modern pharmaceutical industry, and it is increasingly favored in the freeze-drying industry. The liquid nitrogen small-scale freeze dryer has advanced technology and overcomes many shortcomings inherent in the original compressor refrigeration system, and can better meet the requirements of the modern freeze-drying process. It is 2-3 times longer than mechanical refrigeration, which can meet the requirements of conventional freeze-drying and rapid crystallization process. Especially after SIP, it can directly start the refrigeration system, shorten the interval between two freeze-drying, shorten the batch operation time and improve production. effectivenes， production capacity.