Ljusnans Vattenregleringforetag is responsible for adjustment of the water supply for power production in Ljusnan, Sweden. The company supervises more than 30 reservoirs with a total water volume of approximately 1,500Mm3.
The Lossen basin with its 500Mm3 has an extensive drainage works downstream towards the dam. A number of the wells are interconnected - 17 conection points within the wells contained equipment installed for electronic leak detection. Due to humid conditions in the wells, incidents with malfunctioning equipment occured, creating problems for the surveillance personnel.
A Munters ML690 dehumidifier with modulating thyristor control of the heater soon solved the problem. Together with a humidity sensor placed in the dry air duct, the Munters dehumidifer was placed in a building situated centrally within the drainage system. Air distribution ducts with a total length of 600 meters were laid into the soil to distribute the dry air into the 17 wells. In this way condensation and high humidity was avoided ensuring that the leak detection equpiment now functions reliably year- round and with less malfunctions, maintenance has been reduced too.
Munters systems have been used extensively in the protection of metallic components, contacts and switchgear where controlling the climate with a humidity below 50% ensures that corrosion is arrested.
The principle of Munters desiccant dehumidifiers is very simple. Moisture is absorbed onto a slowly-revolving desiccant wheel as air passes through it. The air leaving the other side of the wheel is dry. Another air-stream drives off the moisture which has collected on the drying side of the dehumidifier which is either vented outside or discharged elsewhere. As all the moisture is removed as water vapour by the desiccant wheel, the dehumidifier can operate effectively even at very low temperatures and still maintain the desired humidity conditions.
Munters ML Series incorporates a purge sector which simultaneously recovers heat - thus reducing the electrical power requirement. Consequently providing efficient performance as well as effective control of relative humidity.