Freeze Dryer

What is Freeze Drying? How does it work?

Freeze dryer supplier Beijing Songyuan tells you that freeze-drying is a very healthy way. Whether it is for food or medicine, the benefits of freeze-drying are numerous, such as preservation methods and storage time, as for freeze-drying. The advantages can be linked to http://en.bjsyhx.com.cn/newsshow_30.html This section details the advantages of freeze drying. In fact, freeze drying is now more widely used, so the price of freeze dryer is also The supply and demand of the market are being adjusted, and the price of the freeze dryer varies with the price of its properties. The specific price parameters can be directly contacted by us.

Freeze drying and lyophilization are synonymous. Freeze drying is a water removal process typically used to preserve perishable materials, to extend shelf life or make the material more convenient for transport. Freeze drying works by freezing the material, then reducing the pressure and adding heat to allow the frozen water in the material to sublimate.

Freeze Drying’s 3 Primary Stages

Freeze drying occurs in three phases, with the first and most critical being the freezing phase. Proper freeze drying can reduce drying times by 30%.

Freezing Phase

 There are various methods to freezing the product. Freezing can be done in a freezer, a chilled bath (shell freezer) or on a shelf in the freeze dryer. Cooling the material below its triple point ensures that sublimation, rather than melting, will occur. This preserves its physical form.

Freeze drying is easiest to accomplish using large ice crystals, which can be produced by slow freezing or annealing. However, with biological materials, when crystals are too large they may break the cell walls, and that leads to less-than-ideal freeze drying results. To prevent this, the freezing is done rapidly. For materials that tend to precipitate, annealing can be used. This process involves fast freezing, then raising the product temperature to allow the crystals to grow.

Primary Drying (Sublimation) Phase

Freeze drying’s second phase is primary drying (sublimation), in which the pressure is lowered and heat is added to the material in order for the water to sublimate. The vacuum speeds sublimation. The cold condenser provides a surface for the water vapor to adhere and solidify. The condenser also protects the vacuum pump from the water vapor. About 95% of the water in the material is removed in this phase. Primary drying can be a slow process. Too much heat can alter the structure of the material.

Secondary Drying (Adsorption) Phase

Freeze drying’s final phase is secondary drying (adsorption), during which the ionically-bound water molecules are removed. By raising the temperature higher than in the primary drying phase, the bonds are broken between the material and the water molecules. Freeze dried materials retain a porous structure. After the freeze drying process is complete, the vacuum can be broken with an inert gas before the material is sealed. Most materials can be dried to 1-5% residual moisture.

Freeze Dryer Characteristics
1, liquid crystal display, Chinese interface, with sample drying curve;
2. Imported compressors, with the addition of heat exchangers, increase the cooling capacity and improve the water catching capacity;
3, the cold trap opening is large, no inner coil, with sample pre-freezing function;
4, pre-cooling frame, can be used as a diversion bucket to speed up the drying speed;
5, cold trap and operating surface is all stainless steel, corrosion-resistant and easy to clean, transparent bell jar.
6, transparent bell-type drying room, safe and intuitive;
7. Stainless steel sample holder, the spacing of common sample trays is adjustable;
8. Novel design, small size and convenient operation, reducing the occupation of laboratory countertops;
9, optional nitrogen gas filling valve.