What happens to slag from blast furnace?
If the molten slag is cooled and solidified by rapid water quenching to a glassy state, little or no crystallization occurs. This process results in the formation of sand size (or frit-like) fragments, usually with some friable clinkerlike material.
What is added to the blast furnace to produce slag?
Blast furnace slag (BFS) is a by-product from iron production in blast furnaces, which are fed by a mixture of iron-ore, coke and limestone. In the process, the iron ore is reduced to iron while all remaining materials form the slag, which is tapped off as a molten liquid and cooled.
Is blast furnace slag acidic?
Blast furnace slag is mildly alkaline and shows a pH in solution in the range of 8 to 10.
What is blast furnace slag cement?
Slag cement is a hydraulic cement formed when granulated blast furnace slag (GGBFS) is ground to suitable fineness and is used to replace a portion of portland cement. It is a recovered industrial by-product of an iron blast furnace.
What happens slag?
While most of the furnace slag is recycled for use as an aggregate, excess steel slag from other operations (raker, ladle, clean out, or pit slag) is usually sent to landfills for disposal. Steel slag can normally be obtained from slag processors who collect the slag from steel-making facilities.
What are the main content of the slag?
The primary components of iron and steel slag are limestone (CaO) and silica (SiO2). Other components of blast furnace slag include alumina (Alsub>2O3) and magnesium oxide (MgO), as well as a small amount of sulfur (S), while steelmaking slag contains iron oxide (FeO) and magnesium oxide (MgO).
What is the purpose of slag?
Slag’s purpose is two-fold. It protects the weld from oxidation and contamination from the atmosphere. It also helps keep the molten weld pool in the joint as it cools, which is especially important for out-of-position welding.
What is slag mineral?
Slags are nonmetallic byproducts of many metallurgical operations and consist primarily of calcium, magnesium, and aluminum silicates in various combinations. Iron and steel slags are coproducts of iron and steel manufacturing.
How is slag produced?
Steel slag, a by-product of steel making, is produced during the separation of the molten steel from impurities in steel-making furnaces. The slag occurs as a molten liquid melt and is a complex solution of silicates and oxides that solidifies upon cooling.
Is furnace slag magnetic?
Iron ore and iron slag can also both be magnetic.
What do they do with slag?
According to the National Slag Association website, common uses for slag include: Aggregate in granular base, embankments, engineered fill, highway shoulders, and hot mix asphalt pavement. Concrete aggregate in bridge construction and in concrete masonry. Agricultural applications to increase crop yield.