A path through a slag heap in Clarkdale, Arizona, showing the striations from the now rusting corrugated sheets used to hold it back. Clarkdale is a town in Yavapai County, Arizona, United States.

Slag is the by-product of smelting ore to purify metals. A by-product is a secondary or incidental product deriving from a Manufacturing process a Chemical reaction or a biochemical pathway and is not the primary product Chemical reduction, or smelting, is a form of Extractive metallurgy. An ore is a volume of rock containing components or Minerals in a mode of occurrence that renders it valuable for mining The M acro E xpansion T emplate A ttribute L anguage complements TAL, providing macros which allow the reuse of code across They can be considered to be a mixture of metal oxides; however, they can contain metal sulfides (see also matte) and metal atoms in the elemental form. An oxide is a Chemical compound containing at least one Oxygen atom as well as at least one other element The term sulfide ( sulphide in British English) refers to several types of Chemical compounds containing Sulfur in its lowest Oxidation Matte is a term used in the field of Pyrometallurgy given to the molten metal Sulfide phases typically formed during Smelting of Copper, History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny While slags are generally used as a waste removal mechanism in metal smelting, they can also serve other purposes, such as assisting in smelt temperature control and minimizing re-oxidation of the final liquid metal product before casting. Temperature control is a process in which the temperature of an object is measured and the passage of heat energy into or out of the object is adjusted to achieve a desired temperature Casting is a manufacturing process by which a liquid material is (usually poured into a mold which

In nature, the ores of metals such as iron, copper, lead, aluminium, and other metals are found in impure states, often oxidized and mixed in with silicates of other metals. Iron (ˈаɪɚn is a Chemical element with the symbol Fe (ferrum and Atomic number 26 Copper (ˈkɒpɚ is a Chemical element with the symbol Cu (cuprum and Atomic number 29 Characteristics Lead has a dull luster and is a dense, Ductile, very soft highly WikipediaNaming Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state For the Artificial intelligence Androids of the 1990s Science fiction series Space Above and Beyond, see Silicate (AI During smelting, when the ore is exposed to high temperatures, these impurities are separated from the molten metal and can be removed. The collection of compounds that is removed is the slag. However, in many smelting processes, oxides are introduced in order to control the slag chemistry, assisting in the removal of impurities and protecting the furnace refractory lining from excessive wear. A refractory is a material that retains its strength at high Temperatures ASTM C71 defines refractories as "non-metallic materials having those chemical and physical In this case, the slag is then termed synthetic. A good example is steelmaking slag: quicklime and magnesite are introduced for refractory protection, neutralising the alumina and silica separated from the metal, and assist in the removal of sulfur and phosphorous from the steel. Calcium oxide ( CaO) commonly known as burnt lime, lime or quicklime, is a widely used Chemical compound. Magnesite is not to be confused with Magnetite or Magnemite. Magnesite is Magnesium carbonate, Mg[[carbon The Chemical compound silicon dioxide, also known as silica or silox (from the Latin " Silex " is an Oxide

Ferrous and non-ferrous smelting processes produce different slags. Ferrous, in the chemical science realm indicates a bivalent iron compound (+2 oxidation state (as opposed to Ferric, which indicates a trivalent iron compound (+3 oxidation Ferrous, in the chemical science realm indicates a bivalent iron compound (+2 oxidation state (as opposed to Ferric, which indicates a trivalent iron compound (+3 oxidation The smelting of copper and lead in non-ferrous smelting, for instance, is designed to remove the iron and silica that often occurs with those ores and separates it as an iron silicate based slag. Slag from steel mills in ferrous smelting, on the other hand, is designed to minimize iron loss and so mainly contains oxides of calcium, magnesium, and aluminium. Steel Mill was one of Bruce Springsteen 's early bands and performed regularly on the Jersey Shore, in Virginia, and also in California from 1969 Calcium (ˈkælsiəm is the Chemical element with the symbol Ca and Atomic number 20 Magnesium (mægˈniːziəm is a Chemical element with the symbol Mg, Atomic number 12 Atomic weight 24 WikipediaNaming

In some places in northern Michigan, the slag waste was dumped into the water. This combined with such minerals as dolomite and created a glass-like rock that is very attractive. These slag rocks formed green, purple and bright blue mixtures that are often used by local jewelers in jewellery.

Slag has many commercial uses, and is rarely thrown away. It is often reprocessed to separate any other metals that it may contain. The remnants of this recovery can be used in railroad track ballast, and as fertilizer. "Railroad" and "Railway" both redirect here For other uses see Railroad (disambiguation. Track ballast forms the trackbed upon which Railroad ties (US or railway sleepers (UK are laid Fertilizers ( also spelt fertiliser are chemical compounds given to Plants to promote growth they are usually applied either through the soil for uptake by plant It has been used as a road base material and as a cheap and durable means of roughening sloping faces of seawalls in order to progressively arrest the movement of waves. A seawall is a form of hard and strong Coastal defence constructed on the inland part of a Coast to reduce the effects of strong Waves. A wave is a disturbance that propagates through Space and Time, usually with transference of Energy.

Ground granulated slag is often used in concrete in combination with Portland cement as part of a blended cement. Portland cement is the most common type of Cement in general usage in many parts of the world as it is a basic ingredient of Concrete, mortar, Stucco In the most general sense of the word a cement is a binder a substance which sets and hardens independently and can bind other materials together Ground granulated slag reacts with water to produce cementitious properties. Concrete containing ground granulated slag develops strength over a longer period, leading to reduced permeability and better durability properties. Since the unit volume of Portland cement will also be reduced, concrete is less vulnerable to alkali-silica and sulfate attack. Alkali-Silica Reaction (ASR is a reaction between reactive Silica (in the Concrete aggregates and an Alkali (usually present in the Cement)

Basic slag

Basic slag is a byproduct of steelmaking by the basic version of the Bessemer process or the Linz-Donawitz process. Steelmaking is the second step in producing Steel from Iron ore. The Bessemer process was the first inexpensive Industrial process for the mass-production of Steel from molten Pig iron. Basic oxygen steelmaking ( BOS BOF Linz-Donawitz-Verfahren LD-converter) is a method of Steelmaking in which carbon-rich molten iron is made into Steel It is largely limestone or dolomite which has absorbed phosphate from the iron ore being smelted. Limestone is a Sedimentary rock composed largely of the Mineral Calcite ( Calcium carbonate: CaCO3 Dolomite (ˈdɒləmaɪt is the name of a Sedimentary Carbonate rock and a Mineral, both composed A phosphate, an Inorganic chemical, is a salt of Phosphoric acid. Smelts are a Family, Osmeridae, of small Anadromous Fish. They are common in the North American Great Lakes and in the lakes Because of the slowly-released phosphate content, as well as for its liming effect, it is valued as fertilizer in gardens and farms in steelmaking areas. Liming is the application of Calcium and Magnesium rich materials to Soil in various forms including Marl, Chalk, Limestone Fertilizers ( also spelt fertiliser are chemical compounds given to Plants to promote growth they are usually applied either through the soil for uptake by plant According to the American Association of Plant Food Control Officials, basic slag must contain at least 12% total phosphoric acid (P₂O₅) or be labeled "low phosphate". Phosphoric acid, also known as orthophosphoric acid or phosphoric(V acid, is a mineral (inorganic acid having the Chemical formula ^[1]

See also

• Ground granulated blast furnace slag
• Cement
• Fly ash
• Matte (metallurgy)
• Pozzolan
• Dross
• Slag heap

References

• Dimitrova, S. V. (1996). "Metal sorption on blast-furnace slag". Water Research 30 (1): 228-232.  

• Roy, D. M. (1982). "Hydration, structure, and properties of blast furnace slag cements, mortars, and concrete". ACI Journal Proceedings 79 (6).  

• Fredericci, C. ; Zanotto, E. D. , Ziemath, E. C. (2000). "Crystallization mechanism and properties of a blast furnace slag glass". Journal of Non-Crystalline Solids 273 (1-3): 64-75.