The raw material for Hyttsten and Hyttsand is blast furnace slag, which is produced parallel to iron manufacture in blast furnaces. At the SSAB plants approximately 500,000 tons of blast furnace slag is produced per annum. The slag which floats above the iron is tapped into a slag ladle through a runner. While draining, the blast furnace slag has a temperature of approximately 1500°C. Correctly treated, this can be transformed into products with very special properties. Blast furnace slag, depending on the method of cooling, produces two main proudcts: Hyttsten and Hyttsand.
When the Hyttsten has cooled, it is broken, crushed and screened with machinery to the desired selection. Usually the same range as crushed rock.
Hyttsten consists mainly of remelted natural kinds of rock and contains mostly Silicone and Calcium.The product has properties of low density, high friction, high insulation and cementing properties.
When the blast furnace slag is cooled quickly in water, it becomes a light granuled sand-like product, this is called Hyttsand. Hyttsand with its granuled, amorphous structure has other properties compared to the air-cooled slag.
From an environmental point of view Hyttsten is often a better alternative to natural gravel and crushed rock.