A freeze-drying machine first freezes water containing substances into a solid state, and then sublimates the solid water into a gaseous state, thereby removing water and preserving the substance. In the process of compressed air drying, its freeze-drying is to reduce the temperature of the compressed air and separate the moisture in the compressed air.

The working principle of a refrigerated dryer is to use a refrigerant to cool compressed air to a certain dew point, separate supersaturated water, and separate liquid water through a steam water separator to achieve the purpose of drying. However, the dew point value of the equipment outlet pressure cannot reach the temperature below the freezing point of water. Its notable feature is that it can work continuously, without the need for regeneration, and has low energy consumption.

The adsorption dryer uses silica gel, Activated alumina, molecular sieve and other adsorbents to absorb the moisture in the compressed air to achieve the drying purpose. This method can easily reduce the pressure dew point of compressed air to a temperature lower than the freezing point of water. However, due to the limited adsorption capacity of the adsorbent itself, the method of alternating adsorption between two or more towers must be used, and the drying of compressed air should be carried out continuously. There are many types of dryers on the market, but they all use the principle of adsorption dehydration. The difference lies in the way of regeneration.

The difference between a freeze dryer and an adsorption dryer is not only in terms of principle, but also in terms of performance, operating costs, maintenance costs, procurement costs, and more. For more detailed information, please refer to the following text.

1£º Performance differences

The energy consumption and operating cost of a refrigerated dryer are lower than those of an adsorption dryer, and its pressure dew point is usually above 3 ¡æ. For general manufacturing processes, choosing a refrigerated dryer is sufficient; For some compressed gases with higher requirements and the need for dryness, adsorption dryers can be chosen.

2£º Differences in operating costs

Due to the differences in the dew point values that can be achieved by the compressed air processed by the two devices, they cannot be simply replaced, so the operating costs are not comparable. Their differences are more in comparison between the same type of equipment, such as selecting different types of heat exchangers, different refrigerants, and so on

3£º Maintenance costs

The freeze-drying machine uses a sealed refrigeration system, where the refrigerant is not exposed to the atmosphere, resulting in lower system maintenance costs.

The adsorption dryer involves frequent valve switching between adsorption towers, and suction dryers with thermal regeneration also have high and low temperature switching, resulting in relatively high maintenance costs for valves. Additionally, the adsorption dryer requires regular replacement of the adsorbent, resulting in higher maintenance costs.

4£º Acquisition cost

From the current sales prices on the market, among products of the same brand, the selling price of adsorption dryers with the same processing capacity will be higher than that of refrigeration dryers.