Dehumidification ensures ideal film storage conditions at Filminstituttet

The films are acetate films that must be stored in stable conditions with a temperature of +5°C and a relative humidity of 30% RH. The films have previously been stored in a warehouse, where a refrigeration system only had to ensure the correct temperature and humidity conditions. But the relative humidity could not be kept constant and sufficiently low throughout the year. When the new premises in Glostrup were to be furnished, it was crucial that the storage conditions were stable, and this is where Munters A/S came into the picture. The 2,500 m3 archive room was designed as a cold room, where a Munters desiccant dehumidification system and a cooling system are now controlled and operate independently of each other. The dehumidifier sucks in air from the cold room and dehumidifies this air flow when passing through the dehumidifier's rotor. The dry air from the dehumidifier is then blown into the room immediately before the cooling system's evaporator, and the cold and dry air is distributed in the room via air supply bags with nozzles. An electronic hygrostat – built into the dehumidifier – ensures that the humidity in the cold room never exceeds 30% RH and that the cooling system maintains a temperature of 5°C.

The Munters solution

Since new facilities in Glostrup were being built, it was crucial that storage conditions were stable. Without Munters cooling systems, the 2.500m3 archive room was like a refrigerator. Now cooling and temperature are independently controlled. The dehumidifier draws air from the cooling space and dehumidifies the air passing through the dehumidifier rotor. The air that should be dried passes through the desiccant wheel and the desiccant removes the water vapor from the air and retains the water while rotating. As the moisture-laden desiccant passes through the regeneration sector, the water vapor is transferred to a heated airstream, which is exhausted outside. This continuous process provides a highly effective, non-stop dehumidification.