Drying is a very old operation, but the heating and drying of powders and biological products often irreversible agglomeration of particles.In the preparation of fine powders, the particles in the liquid phase will agglomerate into dispersed agglomerates after drying, which is mainly Because the water is emitted from the pores between the particles during the drying process of the ordinary particles, the additional pressure caused by the surface tension presses the particles together to form en klump.
And freeze drying can bm the 1 problem, freeze drying is to freeze the gel or blood to be dried into a solid first, and then to remove the water by sublimation to vaporize the water in a reasonable condition, due to the vaporization of ice The process does not affect the aggregation state of the solid particles, so the original particles can be kept intact without being compacted and agglomerated.In addition, freeze-drying is often suitable for processing Biologiske produkter, såsom blod, fordi det ikke fungerer ved høje temperaturer og kan FZ biologisk produktforringelse.
Produktets fugtighed, ydelsen af frysetørreren, kontroltidspunktet for den analytiske tørring og temperaturen på den analytiske tørring er de vigtigste faktorer, der påvirker fugtigheden. For lyofiliserede produkter er fugtighedsindholdet mindre end eller lig med 3%. Det høje fugtighedsindhold i frysetørrede produkter får produkterne til at nedbrydes og krympe.