How stone wool is made?
The Rockwool Group has spent more than 70 years constantly improving the production process.
In the beginning everything was done manually, from the trusted employee who shoveled the approximately right amounts of raw material into the furnace and to the people wrapping up the final product.
Today a highly sophisticated machinery ensures the quick and steady production of a superior stone wool quality at an ever lower cost.
From volcano to wool
The myth of stone wool
The idea of producing stone wool came from Hawaii. After the volcanic eruptions on the island the natives found soft strands of melted stone lying on the ground. They thought it was hair from their goddess, Madame Pele, that the temperamental lady had torn out in her rage.
Today we know much more about the unique properties of the stone wool fibres, which make the material perfectly suited for a wide range of purposes.
That is why the Rockwool Group has tried to imitate the natural process of Hawaiian volcanos for more than 70 years now.
How is it done?
Raw material and coke are automatically fed from the top of the cupola furnace. The melt runs out of the bottom of the furnace and onto the spinning machine, where the fibres are spun. Minor amounts of binder and oil are added, and the wool is collected on a belt conveyor in the spinning chamber. The structure and density of the wool are adjusted before it enters the curing oven. These properties are maintained after the binder has been cured.
The cured wool then proceeds to the cutting saws and packing equipment or is led to off-line equipment for special treatment.
The off-gases from the production - furnace, spinning chamber, curing oven - are cleaned in filters and after-burners before they enter the chimney. The waste inevitably created during the production is re-cycled.