CVD-450 Vacuum Freeze Dryer — 4.5㎡ drying area, 100kg/batch, 12–16h cycle

CVD-450 is a vacuum freeze dryer with a drying area of 4.5㎡. The drying chamber is a Φ1.5×1.5m cylindrical structure with a chamber volume of 2.25m³, a nominal load of 100kg per batch, a complete freeze-drying cycle of 12~16 hours, and an ultimate vacuum of ≤7Pa. The unit is equipped with a 33.4kW Bitzer low-temperature screw compressor and a two-stage vacuum system consisting of a Busch rotary vane pump plus a ZJ300 Roots pump. The installed power is 52.65kW, and the footprint is L7×W5×H2.6m.

This class of equipment is mainly used for small-to-medium batch production of heat-sensitive materials such as asparagus, mushrooms, and fruit and vegetable crisps: the material is first frozen, then under high vacuum the ice sublimes directly, preserving shape, color, and rehydration after drying.

Where it is used

4.5㎡ is the drying area, not the chamber volume; how much fresh material can be loaded per batch depends on material density, slice thickness, and tray loading method. Finished product weight and input material weight are not the same figure.

How freeze-drying works

Primary drying accounts for about 60~70% of the entire cycle. During this period the water vapor from sublimation is most concentrated, and the cold trap must continuously condense the vapor into frost; otherwise vapor entering the vacuum pump will emulsify the pump oil and reduce pumping speed.

Technical parameters

Quick specifications

Full parameters

Condensation and water capture configuration

Freeze dryers do not have A/W/E suffix distinctions for compressor type; the 450 in the model refers to a drying area of 4.5㎡ (area×100). Condenser type, defrosting method, and cold trap temperature need to be specified in the order according to the material and on-site water supply conditions.

Main configuration list

Why choose it

• 4.5㎡ with 100kg, bridging pilot and mass production. Profiles developed on laboratory models can be reproduced directly at this level, without having to buy equipment of ten square meters or more right away, and without producing only a few kilograms per batch.
• 12~16 hours per cycle, suitable for heat-sensitive materials. Materials such as asparagus and mushrooms are sensitive to prolonged heating; a short cycle means more batches from the same shelf area, with less quality variation.
• Two-stage vacuum brings the ultimate vacuum down to ≤7Pa. The rotary vane pump first evacuates the chamber below 1kPa, then the Roots pump takes over, so the temperature at the sublimation interface can be held down; the color and rehydration of asparagus depend on this stage.
• Complete unit 3800kg, footprint L7×W5×H2.6m. It can be lifted into position after landing on site; the water-cooled configuration requires the cooling tower location and water supply/drainage to be arranged at the same time.

FAQ

How much fresh material can actually be loaded per batch?

The nominal capacity of 100kg refers to the weight of fresh material loaded on standard trays at conventional loading thickness. Actual loading depends on material density, slice thickness, and tray loading method: thicker slices and higher stacking increase the load, but also lengthen primary drying time. Finished product weight depends on the initial moisture content and target moisture content of the material, and is not the same figure as the input weight. Provide the material name, input weight per batch, and moisture content to the engineer, and the loading and profile can be checked for that material.

How is the 12~16 hours calculated, and can it be shorter?

A cycle consists of three stages: pre-freezing, primary drying, and secondary drying. Primary drying accounts for 60~70% and is the largest part of the time. To shorten it, usually start from the material side: slicing thinner, spreading more evenly, and lowering the initial moisture content are more effective than simply increasing power. For methods of setting the eutectic point and freeze-drying profile, refer to the Technical Library; the specific profile is determined by trial cooling for the material.

Why does the ultimate vacuum need to reach ≤7Pa?

Freeze-drying relies on ice sublimation, and the vacuum level determines the temperature at the sublimation interface. If the vacuum is insufficient, ice sublimates only at a higher temperature, and the material temperature rises accordingly; heat-sensitive materials such as asparagus are then prone to discoloration and collapse. ≤7Pa is the margin left for such materials, and only a two-stage unit can maintain it during the peak sublimation period.

What site conditions need to be prepared?

Power supply 380V/50Hz/3P, installed power 52.65kW; the water-cooled configuration requires a cooling tower installation location, circulating water pump, and water supply/drainage; the equipment footprint is L7×W5×H2.6m, with additional space for operation and maintenance; the drying chamber door must have sufficient width for material carts to pass. The specific power distribution list is issued according to the final technical proposal.

What is the difference between CVD-450 and the 5㎡ class CVD-500?

The drying areas differ by only 0.5㎡, but they follow two different configuration routes. CVD-450 is equipped with a 33.4kW low-temperature screw, a rotary vane pump plus Roots pump two-stage unit, and water cooling, with a cycle of 12~16 hours, aimed at heat-sensitive precision materials such as asparagus and mushrooms; CVD-500 is a general configuration with a cycle of about 25 hours, aimed at conventional batch production of fruit and vegetable crisps and pet food. Which one to choose depends first on whether the material is heat-sensitive and whether a short cycle is required.

To calculate loading, eutectic point, or freeze-drying profile for a material, send us the material name, input weight per batch, and moisture content, and the engineer will provide the selection configuration; you can also first view the freeze dryer series page, or contact us directly.