Energy-saving SECOTEC refrigeration dryers from 5.1 to 34 m³/min

Thanks to cycling control mode and high storage density, the new generation of SECOTEC refrigeration dryers requires very little electrical power, almost regardless of load.

In contrast to other typical systems on the market, excess cooling power is not wasted, but rather used to cool down a thermal mass. Once cooled, it supplies cooling for compressed air drying, eliminating the need for additional electric power.

Furthermore, the new design ensures minimal maintenance requirement and service work is made quick and easy.

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• Life-Cycle-Cost Management

The load on a refrigeration dryer doesn't just depend on the volume of compressed air to be dried (grey area), but more importantly depends on how much water the incoming compressed air contains. The volume of water (moisture) increases as the temperature rises, so the load on refrigeration dryers increases dramatically when ambient temperatures are high, such as during summer (yellow curve).

Conversely, when the temperature falls in winter (turquoise curve), there is less load on refrigeration dryers. To maintain a stable pressure dew point throughout all these fluctuations, refrigeration dryers should always be designed to provide sufficient performance during peak load times, and should also have additional capacity in reserve.

Like the flow rate and temperature range, refrigeration dryers are always operating within the load range of 0 to 100 %. Because SECOTEC storage control ensures energy is only used as needed across this entire load range, users benefit from exceptional savings.

The duty-cycle of refrigeration dryers is always fluctuating between 0 and 100 %. Unlike conventional partial-load control systems, SECOTEC storage control precisely adjusts electrical power consumption during all load phases.

This allows SECOTEC refrigeration dryers to save almost 60 % of energy costs compared to refrigeration dryers with hot gas bypass control running at an average of 40% of capacity.

In contrast to conventional systems, the thermal mass in SECOTEC dryers always remains cool. This means compressed air can be dried effectively even during start-up phases. The high-quality insulation around the thermal mass also helps to keep energy use to a minimum. With SECOTEC refrigeration dryers, compressed air drying takes place with outstanding energy efficiency and it's especially gentle on the equipment thanks to the high thermal mass capacity.

SECOTEC refrigeration dryers efficiently maintain pressure dew points of up to +3°C during full load operation. Thanks to their narrow fluctuation range, pressure dew points are also more stable during partial load operation than is the case with conventional refrigeration dryers. 

Conventional refrigeration dryers with switching operating modes, but without an additional thermal mass, use the heat exchanger material itself as a thermal mass. In these dryers it is therefore necessary to switch the refrigerant compressors and fan motors on and off much more frequently, in order to maintain the required cooling performance. 

To reduce switching frequency and wear, the refrigerant circuit therefore only switches on at much higher pressure dew points. The resulting fluctuations in the pressure dew point negatively affect drying performance. This can be risky, since corrosion can take hold even with relative compressed air humidity of 40 % – corrosion can therefore occur even without condensate formation. 

SECOTEC refrigeration dryers, on the other hand, ensure long-life operation thanks to their high thermal mass storage capacity. Once the thermal mass has been charged, the refrigerant compressor and fan motor can remain switched off for much longer without impacting pressure dew point stability.

1. Compressed air inlet
2. Condensate outlet
3. Refrigerant inlet (cold)
4. Refrigerant outlet (warm)
5. Heat transfer
6. Compressed air outlet

TD, TE and TF series refrigeration dryers are equipped with the innovative SECOPACK LS heat exchanger system. Its latent heat thermal mass is composed of a phase change material. Compressed air warms the material until its melting point (thermal mass discharge), absorbing latent melting heat in the process. This is significantly greater than the amount of heat that it can absorb based on its normal specific heat capacity (without phase change). The latent thermal mass in TE and TF series dryers therefore has a significantly higher thermal storage density and requires 98 % less storage material to achieve the same capacity as conventional storage media.

The key advantages: high thermal capacity for stable pressure dew points and material-friendly operation combined with dramatically reduced unit footprint.