Twenty year old VOD system is one of the most modern

Our 20 year old VOD system is
one of the most modern

The year of 2019 marks a huge milestone for Gefa System. This year, we have been providing our demand controlled ventilation system for LKAB, for twenty years. The LKAB underground mine in Malmberget is one of the worlds most high tech underground mines with the main level currently at 1250 metres below the surface.


A lot of things have happened within the mining site since we installed the first units in 1999. During these years, we have added more control units as the mine has been getting larger and more complex.

Ulf karlsson-arctic vent control-standing infront of fans

To save energy and reduce emissions, LKAB needs a VOD system that can supply the right areas of the mine with air, at the right time.

Out of the twenty ore bodies located in Malmberget, ten are currently being mined. LKAB mines a total of 17,4 tonnes of iron ore here every year. The large working site means lots of activities going on under ground at the same time, and a lot of people working there.


That puts a lot of pressure on the ventilation system’s functionality and efficiency. They currently pump 1400-1700 cubic air into the mine every second.


This VOD system saves us about 57-74mw per year per fan, depending on what type of fan it is. It also decreases the carbon monoxide and NOx due to less required heating of the air, says Robert Hansson, Ventilation engineer at LKAB.


The mine air is heated by burning oil. With this system LKAB use somewhere around 10 cubic meter less oil every year. The ventilation on demand system that we provide for LKAB is one of the oldest, yet one of the most modern systems there is.

During spring 2019 we will deliver eighteen new VOD control units that will integrate with the already existing system.

The new units are prepared for bluetooth and have more precise control. For example we can control the fans on both sides in the plate. This technique is brand new and will reduce the electrical costs.


We need to be able to control the airflow within the mining site. This system allows us to automatically direct ventilation to areas where we have machines working. It also allows us to control the ventilation to the right areas when we blast. That’s one of the key features Robert Hansson says.


The new units will help to better optimize the fresh air that goes into the mine and also control the evacuating air better.


We are looking to further reduce carbon monoxide and NOx levels to decrease our environmental footprint and the new units will help us on our road to reach that goal, says Robert Hansson.