There are three main kinds of freeze dryers: rotary, manifold and tray freeze dryers. Rotary freeze dryers are generally used when working with liquids. Small amounts of material are frozen by manifold dryers, and tray freeze dryers produce the driest product ready for long-term storage. Read More…
Leading Manufacturers
Carrier Vibrating Equipment, Inc.
Louisville, KY | 502-969-3171Carrier is a manufacturer of high quality dryers in addition to many other related products, including coolers, screens, air knife separators, spiral elevators, feeders & conveyors.
Dürr Systems, Inc.
De Pere, WI | 920-336-5715Dürr Megtec provides customized systems for: regulatory compliance; improvement in working environment and in neighbor relations by reducing odor from industrial processes and helping to reduce greenhouse gas emissions and process energy management.
DRI-AIR Industries, Inc.
East Windsor, CT | 860-627-5110Dri-Air Industries' expertise is in plastic drying technology. The plastic drying systems we offer problem solve for drying plastic resins, mixing and blending. Our product line includes industrial dryers, desiccant air dryers and hot air dryers. Newly offered is our micro dryer for micro molding machines.
W.A. Hammond Drierite Co. Ltd.
Xenia, OH | 937-376-2927W.A. Hammond DRIERITE Company manufactures DRIERITE desiccants in many sizes and consistencies and related materials and equipment. Our product line includes gas dryers, compressed air dryers, drying tubes, storage tank vent dryers and truck dryers. Our desiccants prevent mildew, rust and corrosion.
The CMM Group
De Pere, WI | 920-336-9800The CMM Group provides custom-designed industrial dryers and ovens for a wide range of applications in single or multi-zone configurations. The CMM Group designs and builds conveyorized curing, baking and drying ovens for automated production of small-to-medium sized products. Conveyorized roll support web dryers are available in horizontal or vertical tower design and can handle thin film to heavy gauge substrates, narrow to wide, slow or fast speeds.
Altec AIR
Broomfield, CO | 800-521-5351Altec AIR is a leading manufacturer and worldwide distributor of industrial compressed air dryers, laboratory gas generators, purifiers, complete systems and accessories. Altec AIR manufactures a full line of regenerative, desiccant compressed air dryers and absorbers to 50scfm.
Freeze Dryers - Central Air CompressorFreeze dryers are used by the pharmaceutical industry for increasing the shelf life of vaccines, for preserving certain strains of bacteria and for ease of storing and shipping certain products.
Freeze drying removes water and bulk while maintaining flavors and nutritional content and is subsequently used with food and beverages like instant coffee, fruit and herbs. Freeze drying is also useful in chemistry and biotechnology because it can make products easier to dissolve in water and remove impurities. Some museums or conservation agencies use freeze dryers to dry and preserve artifacts, manuscripts and animal or floral specimens.
Freeze Dryers - Central Air CompressorThe three kinds of freeze dryers - rotary, manifold and tray - vary in size and material. The industrial machines are typically tray freeze dryers and can be hundreds of feet long, either vertically or horizontally oriented. Stainless steel is most commonly used because it is sanitary and can be temperature controlled very effectively.
Products are held on trays on shelves in large boxes or carried on a conveyor belt if the dryer is continous. Freeze drying is a three step process. During the initial freezing, the material inside the dryer is cooled below its triple point, which is the lowest temperature at which the solid and liquid phases of the material can exist at the same time.
The temperature is usually between -50° and -80°C, and this is the most important step of the process. After the material is frozen it enters the primary drying phase. The pressure is lowered and enough heat is provided that sublimation occurs. Adding a vacuum to the dryer helps control and maintain pressure, and a cold condenser plate or chamber gives the water vapor a surface to freeze onto after it leaves the material.
The last step removes any unfrozen water molecules. In the secondary drying phase the pressure is lowered again and the temperature is raised, sometimes above the freezing point of 0°C. Any residual water evaporates from the substance, and the final water content is less than 5%.
