Silo Head Space Conditioning

Protecting your products from the effects of high humidity within silos

Engineered for efficiency, built to last.

Why control the relative humidity in silo head spaces?

Materials that are stored in silos can be affected by high relative humidity in the air. Many silos can be affected, for example those containing food stuffs such as flour and sugar, sewerage industry flocculent silos, cement, etc… At lower temperatures, the relative humidity of the head space air will increase when the saturation point is reached. Air will begin to deposit moisture on internal surfaces of the silo. This common problem can be eliminated by ensuring that air in the head space is maintained at a low relative humidity.

The problems

Common problems associated with high humidity in silo head spaces are:

  • Degradation of product quality
  • Irregular product flow
  • Product clumping
  • Increase in microbial activity
  • Increase in product moisture content
  • Condensation forming on internal surfaces

Common materials affected by high humidity

  • Polylactic acids
  • Sugar
  • Food products (milk powder/flour)
  • Lime
  • Fertilizers

The solution to high humidity within silos

The installation of a desiccant dehumidifier in the base of the silo skirt is the simplest, most cost-effective solution. The dehumidified fresh air can be ducted to the head space through either the fill line or via a dedicated dehumidified airline, this causes a slight overpressure in the silo head, with excess air discharged via the vent filter assembly, ensuring that air in the head space is maintained at a low relative humidity.

*It is important to note that the desiccant dehumidifier must be isolated during filling to avoid damage.

In some cases, a recirculation system may be required to achieve very low humidity levels, an example being PLA (Polylactic Acid). In this scenario additional filtration is required to avoid potential damage to the dehumidifier.

The MDC250 provides an ideal dry air head space conditioning solution for many small to medium silos and is often suitable for silos up to 150m³ in volume.

*Optional controller available for monitoring of outlet air condition.

MDC250 Mode of Operation
MDC250 Mode of Operation

MDC250 Integrated Silo cabinet solution

The MDC250 is available pre mounted within a weatherproof cabinet for clients requiring a plug and play solution.


  • Integrated Micatrone HC2 Controller
  • Available with a choice of connections and hose lengths
  • Optional stand with adjustable feet
  • Optional External alarm beacon