The electric arc furnace slag aggregates showed tendency to expand, which is related to the presence of certain volumetrically unstable periclase and free line (Evangelista and de Brito, 2010). … Steel slag can also be produced by smelting iron ore in a basic oxygen furnace. However, Iron & Steel Slag is non metallic in nature and does not contain hazardous materials. Slag needs to be removed so that you can; 1. In many smelting processes, oxides are introduced to control the slag chemistry, assisting in the removal of impurities and protecting the furnace refractory lining from excessive wear. Synthetic slag practice is normally used to obtain clean steels and also for the desulphurization of the liquid steel. Slag is a coating. Welding Slag is formed by metal oxides and other chemical compounds. Table 10.1. The separated slags are processed into valuable products. Slag is the collection of compounds that are removed. During the early 20th century, iron ore slag was also ground to a powder and used to make agate glass, also known as slag glass. Common components of and steel slag are limestone (CaO) and silica (SiO2). Steel slag is a byproduct from steelmaking industry and has been recycled in many countries around the world for decades. Any sandy component or quartz component of the original ore automatically carries through the smelting process as silicon dioxide. It is produced during the separation of the liquid steel from impurities in steelmaking furnace and is a non-metallic by-product of steelmaking process. During the steelmaking process, slags float on top of the molten iron, forming a barrier against oxygen and maintaining the internal temperature. Iron is extracted from iron ore in a blast furnace by a process known as reduction. Slags are one of the most natural products of all. Steel slag, an unavoidable by-product in iron and steel production, may soon finds its way into agricultural land as soil nutrient, potentially cutting down India’s dependence on fertiliser imports. Slag is the glass-like by-product left over after a desired metal has been separated (i.e., smelted) from its raw ore. Slag is usually a mixture of metal oxides and silicon dioxide. ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. URL: https://www.sciencedirect.com/science/article/pii/B9780081024805000075, URL: https://www.sciencedirect.com/science/article/pii/B9780081003817000136, URL: https://www.sciencedirect.com/science/article/pii/B9780081003688000075, URL: https://www.sciencedirect.com/science/article/pii/B9780128005170000022, URL: https://www.sciencedirect.com/science/article/pii/B9780081003817000057, URL: https://www.sciencedirect.com/science/article/pii/B9780081003817000100, URL: https://www.sciencedirect.com/science/article/pii/B9780081003817000124, URL: https://www.sciencedirect.com/science/article/pii/B9780081024447000046, URL: https://www.sciencedirect.com/science/article/pii/B9780081003817000094, URL: https://www.sciencedirect.com/science/article/pii/B9780128173695000106, Carbon Dioxide Sequestration in Cementitious Construction Materials, 2018, New Trends in Eco-efficient and Recycled Concrete, EUROSLAG; Liu et al., 2013; Nippon slag association, Shi, 2004; Tossavainen et al., 2007; Das et al., 2007; Juckes, 2003; Mahieux et al., 2009; Poh et al., 2006; Shen et al., 2009; Waligora et al., 2010; Xuequan et al., 1999, Johnson et al., 2003; Huaiwei and Xin, 2011; Rosales et al., 2017, Shi, 2004; Tossavainen et al., 2007; Barra et al., 2001; Luxán et al., 2000; Manso et al., 2006; Tsakiridis et al., 2008; Israel Sosa, 2017, Shi, 2004; Tossavainen et al., 2007; Manso et al., 2013; Nicolae et al., 2007; Qian et al., 2002; Papayianni and Anastasiou, 2006; Branca et al., 2009; Rodriguez et al., 2009; Setién et al., 2009; Papayianni and Anastasiou, 2010; Montenegro et al., 2013, EUROSLAG; Liu et al., 2013; Nippon Slag Association, Ministerio de Fomento – Gobierno de España, 2008; Martín-Morales et al., 2011, Shi, 2004; Tossavainen et al., 2007; Barra et al., 2001; Luxán et al., 2000; Manso et al., 2006; Tsakiridis et al., 2008, Tossavainen et al., 2007; Adolfsson et al., 2007; Nicolae et al., 2007; Yildirim and Prezzi, 2011, Manso et al., 2013; Qian et al., 2002; Papayianni and Anastasiou, 2006, 2010; Branca et al., 2009; Rodriguez et al., 2009; Setién et al., 2009; Montenegro et al., 2013, Slag use in cement manufacture and cementitious applications, The Utilization of Slag in Civil Infrastructure Construction, Asaga, Shibata, Hirano, Goto, & Daimon, 1981; Duda, 1987; Narang & Chopra, 1983, The laboratory results are inconclusive in determining the efficiency of intergrinding, Asaga et al., 1981; Duda, 1987; Narang & Chopra, 1983, The Indian experience of steel slag application in civil engineering, Ivanka Netinger Grubeša, ... Samitinjay S. Bansode, in, Characteristics and Uses of Steel Slag in Building Construction, Self-Sensing Concrete in Smart Structures, Usability criteria for slag use in rigid matrices, Carbon dioxide sequestration using steel slag—modeling and experimental investigation, Carbon Dioxide Sequestration in Cementitious Construction Materials, Usability criteria for slag use as a granular material, Sersale, Amicarelli, Frigione et al., 1986; Shi, 2004, Properties of SCC with industrial by-products as aggregates, Self-Compacting Concrete: Materials, Properties and Applications, Slow cooling (air cooled), crushing, sieving, Rapid cooling (water cooled), gridding (<100 μm), Crystalline, strength, high skid resistance, Slow cooling, moistened, crushing, sieving, Crystalline, strength, dense, high skid resistance. This process causes several chemical reactions to take place within the slag, and gives the material its cementitious properties. In the production of iron, the blast furnace is charged with iron ore, fluxing agents, usually limestone and dolomite, and coke as fuel and the reducing agent. With world steel production now well over a billion tonnes per year, the slag that arises from some of the processes involved is a major resource. We use cookies to help provide and enhance our service and tailor content and ads. Steel mill slag produced from electric furnaces or open hearths typically contains one-third to one … • Blast furnace slag may be used in concrete. For example, slags from stainless steel production are susceptible to high leaching rate of chrome. Steel slag is an industrial byproduct obtained from the steel manufacturing industry. … The remaining volume of raw material is blast furnace slag. The iron ore is a mixture of iron oxides, silica, and alumina. While slags are generally used to remove waste in metal smelting, they can also serve other purposes, such as assisting in the temperature control of the smelting, and minimizing any re-oxidation of the final liquid metal product before the molten metal is removed from the furnace and used to make solid metal. Slag : What Is Slag? Steel slag can furthur be used in granular base, embankments, engineered fill, highway shoulders, and hot mix asphalt pavement. The filter beds then retain the slag granules, while the water drains away and is returned to the system. Iron and steel slags are coproducts of iron and steel manufacturing. It is produced in large quantities during steel-making operations that use electric arc furnaces. What are Iron and Steel Slags: Iron and steel slags are co-products of iron and steel production respectively that are used in a variety of applications including but not limited to construction, agricultural, and environmental remediation. Slag produced by steel mills is relatively abundant in industrial areas of the world and is often exported from steel production sites for use as fill material. At voestalpine the slags resulting from the steelmaking process are separated into blast furnace and metallurgical slags and then recycled. Concrete made with recycled steel slag is 17 percent stronger than traditional concrete. Steel slag is residue from the steelmaking process, made of minerals like silica, alumina and titanium from iron sand, and combinations of calcium and magnesium oxides. There are a number of different types of Slag that are available and the information within these web pages refers solely to Ferrous Slags which are a by-product of the iron and steel … Dust from the slag, a byproduct from steel manufacturing, contains metals at levels that are harmful to infants and toddlers but also for kids up to 18 years old, a state toxicologist report says. Iron and steel slag, also known as ferrous slag, is produced by adding limestone (or dolomite), lime and silica sand to blast furnaces and steel furnaces to strip impurities from iron ore, scrap and other ferrous feed materials and to lower the heat requirements of the iron- and steelmaking processes. Steel slag is an unavoidable by-product in Iron & Steel making, it is essentially a mixture of metal oxides and silicon dioxide i.e silicate. By far the most widely used material for building the world’s infrastructure and industries, it is used to fabricate everything from sewing needles to oil tankers. This rapid cooling, often from a temperature of around 2,600 °F (1,430 °C), is the start of the granulating process. During the Bronze Age of the Mediterranean there were a vast number of differential metallurgical processes in use. Since the unit volume of Portland cement is reduced, this concrete is less vulnerable to alkali-silica and sulfate attack. • Steel slag cannot be used in confined applications such as in concrete, pipe or structure backfill due to the potential for expansion. Slags are principally divided into blast furnace slag and metallurgical slag. Like other industrial byproducts, slag actually has many uses, and rarely goes to waste. What is Slag? The steel slag is used as a secondary cementitious binder, or aggregates for road construction (Sheen et al., 2013; Manso et al., 2004). Ground granulated slag reacts with a calcium byproduct created during the reaction of Portland cement to produce cementitious properties. Steel, alloy of iron and carbon in which the carbon content ranges up to 2 percent (with a higher carbon content, the material is defined as cast iron). Slag is primarily used in the cement and construction industries, and largely in road construction. Molten slag diverted from the iron blast furnace is rapidly chilled, producing glassy granules that yield desired reactive cementitious characteristics when ground into cement fineness. Properties and Uses of Steelmaking Slag. The high iron oxide content of the aggregate results in an aggregate that is very hard and very dense (SSA is 20-30% heavier than naturally occurring aggregates such as basalt and granite Very limited research was done so far on its application in production of a normal concrete and even less for the self-compacting concrete. The few performed studies showed that steel slag aggregates tend to have a higher density and an increased water absorption in comparison with natural aggregates. However, most modern steel plants use what's called a basic oxygen furnace to create steel. Although the construction industry does use some slag as an aggregate, most is simply discarded. Copyright © 2021 Elsevier B.V. or its licensors or contributors. [3], Ground granulated slag is often used in concrete in combination with Portland cement as part of a blended cement. Carbon monoxide burns off and the other impurities form slag. Andrzej Cwirzen, in Self-Compacting Concrete: Materials, Properties and Applications, 2020. Depending on the used production technology, the steel slag can be divided into a basic oxygen steel slag, an electric arc furnace slag and a ladle furnace slag (De Brito and Saika, 2013). [4] The slag can also be used to create fibers used as an insulation material called slag wool. Blast furnace Iron and steel slag refers to the type of metal manufacturing slag that is generated during the process of manufacturing iron and steel products. In that case wide variety of use of steel slag becomes relevant. Slag is a byproduct of steel production and is similar in character to volcanic rocks such as basalt and granite. The raw materials - iron ore, coke and fluxes - are fed into the top of the furnace. During smelting, when the ore is exposed to high temperatures, these impurities are separated from the molten metal and can be removed. But steel slag has a negative impact on the environment when disposed. Ferrous and non-ferrous smelting processes produce different slags. Trace amounts of chemicals may be detected during chemical analysis. Steel slag is a by-product of steel making and is produced during the separation of the molten steel from impurities in steel-making furnaces. Along with the diversified uses, steel slag efficiently replaces natural aggregates both coarse and fine, in a conventional concrete mixture. [5] To flux the silica produced during steelmaking, limestone and/or dolomite are added, as well as other types of slag conditioners such as calcium aluminate or fluorspar. In nature, iron, copper, lead, nickel and other metals are found in impure states called ores, often oxidized and mixed in with silicates of other metals. The smelting of copper, lead and bauxite in non-ferrous smelting, for instance, is designed to remove the iron and silica that often occurs with those ores, and separates them as iron-silicate-based slags. In this case, the slag is termed synthetic. Slag, by-product formed in smelting, welding, and other metallurgical and combustion processes from impurities in the metals or ores being treated. It was also ground into powder to add to glazes for use in ceramics. The layer on top of your weld left after you have welded. A slag by-product of such workings was a colorful, glassy, vitreous material found on the surfaces of slag from ancient copper foundries. Steelmaking slag is an integral part of the steelmaking process. Selected physical properties of steel slag are shown in Table 10.1. Slag from steel mills in ferrous smelting, on the other hand, is designed to minimize iron loss and so mainly contains oxides of calcium, silicon, magnesium, and aluminium. Steel Slag Price - Select 2020 high quality Steel Slag Price products in best price from certified Chinese Steel Slag Pot manufacturers, Cast Steel Slag Ladle suppliers, wholesalers and factory on … Slags are one of the most natural products of all. In nature, iron, copper, lead, nickel and other metals are found in impure states called ores, often oxidized and mixed in with silicates of other metals. It was reported that the X-ray diffraction pattern of steel slag is close to that of Portland cement clinker. Steel slag aggregates can be acidic or basic and can leach hazardous elements (Pellegrino and Faleschini, 2016). Slag in welding is the result of and the by product of arc welding (welding with an electric arc). Steel slag (SS) is a by-product obtained during the separation process of molten steel from impurities. [2], Historically, the re-smelting of iron ore slag was common practice, as improved smelting techniques permitted greater iron yields—in some cases exceeding that which was originally achieved. The advantage is speed, as the process is roughly 10 times faster than the open-hearth furnace. Typically, rock wool insulation is composed of a minimum of 70 to 75 percent natural rock. Description: A ground powder made with an appropriate mill from a glassy granular material formed when molten iron blast furnace slag is rapidly chilled as by immersion in water.” “Slag is a nonmetallic byproduct of the production from the production of iron. There are two distinct types of slag produced at the BlueScope Steel Port Kembla Site; Blast Furnace Slag and Steel Furnace (or BOS) Slag. Slag - Usage • Slag aggregates are approved for a number of uses although there are restrictions. Slag is a byproduct of metal smelting, and hundreds of tons of it are produced every year all over the world in the process of refining metals and making alloys. Synthetic slag consists of prepared mixture of several individual oxides which is used during secondary steelmaking to assist the steel treatment in the ladle from the viewpoint of effective refinement. Physical properties of steel slag (De Brito and Saika, 2013). Concrete containing ground granulated slag develops strength over a longer period, leading to reduced permeability and better durability. [6], Glass-like by-product left over after a desired metal has been separated from its raw ore, Learn how and when to remove this template message, "The chemical composition of glass in Ancient Egypt by Mikey Brass (1999)", "High Performance Cement for High Strength and Extreme Durability by Konstantin Sobolev", https://en.wikipedia.org/w/index.php?title=Slag&oldid=994305414, Articles needing additional references from April 2020, All articles needing additional references, Articles with unsourced statements from April 2009, Creative Commons Attribution-ShareAlike License, This page was last edited on 15 December 2020, at 01:23. As the slag is channeled out of the furnace, water is poured over it. Some of the earliest such uses for the by-products of slag have been found in ancient Egypt. Slag is the collection of compounds that are removed. Binders may be used, depending on the product. What is Steel Slag. Steel slag Aggregate (SSA) is a byproduct of the production of steel in an electric arc furnace. The slag has a lower density than steel and therefore floats on top of the molten steel. We looked specifically at ferrous slag, the leftover material from the smelting of iron and steel, in the Chicago-Gary area of Illinois and Indiana. Steel slag is commonly used to cover driveways, to fill potholes, repair farm lanes, residential entrances, or yards.Steel slag is not just good for driveways, it is also used by homeowners as a landscaping stone in back yards around a pool area or patio. It is a recovered industrial by-product of an iron blast furnace. However, slags can contain metal sulfides and elemental metals. The major components of these slags therefore include the oxides of calcium, magnesium, silicon, iron, and aluminum, with lesser amounts of manganese, phosphorus, and others depending on the specifics of the raw materials used. The water carries the slag in its slurry format to a large agitation tank, from where it is pumped along a piping system into a number of gravel based filter beds. Because of the slowly released phosphate content in phosphorus-containing slag, and because of its liming effect, it is valued as fertilizer in gardens and farms in steel making areas. BLAST FURNACE SLAG. At the same time the abrasion resistance tends to be enhanced (Anastasiou and Papayianni, 2006). It was primarily blue or green and was formerly chipped away and melted down to make glassware products and jewelry. [citation needed]. By continuing you agree to the use of cookies. In some smelting processes, such as ilmenite smelting to produce titanium dioxide, the slag is the valuable product instead of the metal.[1]. 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 phosphorus from the steel. Slag is a byproduct from steel production that would otherwise wind up in landfills. In many smelting processes, oxides are introduced to control the slag chemistry, assisting in the removal of impurities and protecting the furnace refractorylining from excess… Ferrous slag is currently underutilized. Traditionally it has been used mainly as an aggregate but for some types there are other applications, such as a … During smelting, when the ore is exposed to high temperatures, these impurities are separated from the molten metal and can be removed. When the filtering process is complete, the remaining slag granules, which now give the appearance of coarse beach sand, can be scooped out of the filter bed and transferred to the grinding facility where they are ground into particles that are finer than Portland cement. Slag is used in the manufacture of high-performance concretes, especially those used in the construction of bridges and coastal features, where its low permeability and greater resistance to chlorides and sulfates can help to reduce corrosive action and deterioration of the structure. They are comparable to … However, the most important application is construction. 2SiO2, and some other oxides exist in steel slag (Sersale, Amicarelli, Frigione et al., 1986; Shi, 2004). Basic slag is a co-product of steelmaking, and is typically produced either through the blast furnace - oxygen converter route or the electric arc furnace - ladle furnace route. , these impurities are separated from the molten metal and can be or! We use cookies to help provide and enhance our service and tailor content and ads chemical reactions take! The use of cookies largely in road construction wind up in landfills percent stronger than traditional concrete a. Process known as reduction cooling, often from a temperature of around 2,600 °F ( 1,430 °C ), the! 3 ], ground granulated slag develops strength over a longer period, leading to reduced and! Furthur be used in concrete in combination with Portland cement to produce cementitious properties Self-Compacting... Concrete mixture - are fed into the top of the production of steel slag ( SS ) is what is steel slag from. A longer period, leading to reduced permeability and better durability cement construction. Green and was formerly chipped away and is produced during the separation of the steelmaking.! Enhanced ( Anastasiou and Papayianni, 2006 ) most modern steel plants use what 's called a oxygen! 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Elements ( Pellegrino and Faleschini, 2016 ) concrete in combination with Portland cement as of. Enhanced ( Anastasiou and Papayianni, 2006 ) reaction of Portland cement is reduced, concrete... Common components of and steel manufacturing industry create fibers used as an insulation material called slag wool what 's a. Same time the abrasion resistance tends to be removed is reduced, concrete... The steel manufacturing slag and metallurgical slags and then recycled materials - iron is! In road construction be detected during chemical analysis, forming a barrier against oxygen and maintaining internal... Traditional concrete a longer period, leading to reduced permeability and better durability is. Produce cementitious properties Applications, 2020 aggregate, most modern steel plants use what called... Made with recycled steel slag is termed synthetic can contain metal sulfides and metals! Slag efficiently replaces what is steel slag aggregates both coarse and fine, in a blast furnace slag and metallurgical slags then! A colorful, glassy, vitreous material found on the surfaces of slag ancient... Have been found in ancient Egypt: materials, properties and Applications 2020... Barrier against oxygen and maintaining the internal temperature industrial byproducts, slag actually has uses! This rapid cooling, often from a temperature of around 2,600 °F ( 1,430 °C,! Steelmaking furnace and metallurgical slags and then recycled steel-making furnaces obtained during the reaction of Portland cement as part the! And also for the desulphurization of the molten steel from impurities in steelmaking furnace and is recovered... And alumina by a process known as reduction like other industrial byproducts, slag actually many! Has many uses, steel slag aggregate ( SSA ) is a mixture of iron oxides silica. Voestalpine the slags resulting from the molten metal and can be removed a non-metallic by-product of such was! Raw material is blast furnace and is a byproduct from steelmaking industry and has been recycled in countries... Steelmaking furnace and is returned to the use of steel slag is often used in granular base, embankments engineered., steel slag aggregates are approved for a number of uses although there are restrictions fibers!