A portland cement mixed with a designated amount of ground granulated blast furnace slag. Because of the disputes over the composition of the cement, the manufacturers of cements containing blast furnace slag founded the association of german iron. Effects of blastfurnace slag on natural pozzolanbased geopolymer cement ceramics silikaty 55 1 6878 2011 69 its pozzolanic activity. The results of chemical analysis determined according to astm standard c311 12 are shown in table 1. Characteristics of portland blastfurnace slag cement. Using slag cement in concrete can greatly decrease the amount of portland cement typically used for a specific mixture of concrete. The physical structure and gradation of granulated slag depend on the chemical composition of the slag, its temperature at the time of water quenching, and the. Roads constructed using ld slag demonstrate reduced rutting. Composition and microstructure of 20yearold ordinary. The mineralogical phase composition of the pozzo lan was determined by the use of powder xray. Influence of curing time on the drying shrinkage of.
They showed that slag of the following composition 35% al 2 o 343. Blast furnace slag an overview sciencedirect topics. Slag cement benefits and use in concrete slag cement news. Dicalcium silicate ca 2 sio 4 14284232, merwinite ca 3 mgsi 2 o 8 8644, and gehlenite ca 2 al 2 sio 7 2563. Blast furnace slag is nonreactive in a high alkali environment, such as concrete and soils. Iron ore, coke and limestone are fed into the furnace and the resulting molten slag floats above the molten iron at a temperature of about 15000c to 16000c. Molten slag diverted from the iron blast furnace is rapidly chilled, producing glassy granules that yield. Hiraskar and chetan patil abstractthe iron industries produce a huge quantity of blast furnace slag as byproduct, which is a nonbiodegradable waste material from that only a small percentage of it is used by cement industries to manufacture cement. There are two distinct types of slag produced at the bluescope steel port kembla site. The slag composition that has the minimum corrosion ability is obtained.
Properties significant chemoresistance, and suppression of alkaliaggregate reaction type b and c. This specification covers three strength grades of finely ground granulated blastfurnace slag grades 80, 100, and 120 for use as a cementitious material in concrete and mortars. In the case of steelmaking slag, the slag contains metal elements such as iron in oxide form. Recent developments in slagfuming process 7 0 2n b 0 10 29 30 40 50 60 70 80 90 100 110 120 ti ne,s,inute 2 ovetal eliminative curve chambers.
Use of the cementatious properties of ground granulated blast furnace ggbf slag was reported as early as 1774. Blast furnace slag material description user guidelines. It consists primarily of silicates, aluminosilicates, and calciumaluminasilicates. This can perhaps be explained by the vast amount of blast furnace slag available 6. Ground granulated blast furnace ggbf slag used in concrete. Pelletized slag, ground granulated blast furnace slag ggbfs, blast furnace slag, steel slag, granulated slag, pelletized slag, metallic slag, air cooled slag, nonmetallic slag, slag cement, hydraulic slag cement, slag manufacturer. Aluminachrome brick is the suitable refractory to freeze lining in submerged arc furnace. Nonportland cement activation of blast furnace slag anne elizabeth oberlink university of kentucky, anne. Other components of blast furnace slag include alumina alsub2 o 3 and magnesium oxide mgo, as well as a small amount of sulfur s, while steelmaking slag contains iron oxide feo and magnesium oxide mgo. Portland blast furnace slag cement is a mixture of ordinary portland cement and not more than 65 wt. Mechanochemical modification of cement with high volumes of.
It consists of nonferrous components contained in the iron ore together with limestone as an auxiliary materials and ash from coke. A portland cement mixed with a designated amount of ground granulated blastfurnace slag. It is removed from the blast furnace and allowed to cool. Online slag composition analysis for electric arc furnaces. Use of blast furnace slag as an alternative of natural. Ground granulated blastfurnace slag ggbfs, sometimes simply referred to as slag, is a glassy granular material formed when molten blastfurnace slag is rapidly chilled, as by immersion in water. Recommended citation oberlink, anne elizabeth, nonportland cement activation of blast furnace slag 2010. Hamazaki, properties of granulated blastfurnace slag cement concrete, in proceedings of the fly ash, silica fume, slag, and natural pozzolans in concrete fourth international conference, istanbul, turkey, 1992. Development of engineered cementitious composites with. Analysis of slag flow in blast furnace during the extraction.
The elemental composition of bf slag was investigated by xray fluorescence spectrometry xrf1800, shimadzu, japan, with a rh target used as the target. Early stage dissolution characteristics of aluminosilicate glasses. Due to light color of blast furnace slag, color of slag concrete is lighter in comparison with conventional concrete. The chemical composition of a slag varies considerably depending on the composition of the raw materials in the. Alkaliactivated slag aas binders are produced by alkaline activation of watercooled ground granulated blast furnace slag ggbfs, which is. Blast furnace slag is formed when iron ore or iron pellets, coke and a flux either limestone or dolomite are melted together in a blast furnace. Moreover, deep bluegreen color shown by interior part of slag concrete and can be noticed from slag concrete broken parts, for example, after compressive strength test. Such a slag acquires liquid mobility and trickles down the furnace away from the site where it starts distorting plastically, as soon as possible. The chemical composition of slag is usually expressed in terms of simple. 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. Pyrometallurgy, blast furnace, slag viscosity, slag liquidus temperature, phase equilibria abstract the viscosity of molten slag in blast furnace operations is an important process variable, influencing the rate and location of reactions inside the furnace, as well as the ease with which the final slag could be removed from the. These slags are combined with any carryover of furnace slag and assist in absorbing. Granulated blast furnace slag granulated blast furnace slag is a glassy granular material that varies, depending on the chemical composition and method of production, from a coarse, popcornlike friable structure greater than 4. Blast furnace control using slag viscosities and liquidus.
Groundgranulated blast furnace slag ggbs or ggbfs is obtained by quenching molten iron slag a byproduct of iron and steelmaking from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder. Wash with cool water and a ph neutral soap or a mild skin detergent. Viscosity decreases with basicity for high alumina blast furnace slags with increase in basicity and caf 2. Page 2 blast furnace slag as a concrete aggregate part i properties of blast furnace slag our natural aggregates, such as stone and gravel of suitable quality for concrete making, are rapidly becoming depleted in many localities. The heat of hydration is dependent on the portland. Blast furnace slag granulation ironmaking our activities. The overall conclusion is that with a more reliable composition of hot metal and slag from the taps, the distribution coefficients could be calculated with. It must have appreciable affinity for the gangue constituents to facilitate the production of metal of choice. Blast furnace slag is a coproduct of the iron making process. Grinding reduces the particle size to cement fineness. Use of aircooled blast furnace slag as coarse aggregate. Groundgranulated blastfurnace slag ggbs or ggbfs is obtained by quenching molten iron slag a byproduct of iron and steelmaking from a blast furnace in water or steam, to produce a glassy, granular product that is then dried and ground into a fine powder. The slag shall contain no additions and shall conform to the sulfide sulfur and sulfate chemical composition requirement. In carbon steelmaking it is important to ensure foaming slag conditions, which increases energy efficiency of the eaf.
The latent hydraulic property of the blast furnace slag gives excellent longterm strength. This action exposes fresh sites for further reaction and is supposedly responsible for enhanced slag metal reaction rates, influencing the blast furnace operations and the quality of the metal. Hiraskar and chetan patil abstractthe iron industries produce a huge quantity of blast furnace slag as byproduct, which is a nonbiodegradable waste material from that only a small percentage of it is used by. Blast furnace slag is a nonmetallic coproduct produced in the process. Approximately 110 kg of slag is generated for each ton of converter steel. At the present, most industrial slags are being used without taking full advantage of their properties or disposed rather than used. Cdic can now conduct more than 100 mechanical tests, out of which, 55 tests come under the nabl accreditation. The raw materials iron ore, coke and fluxes are fed into the top of the furnace. Yet from the available heat in the hearth point of view,1 the blast furnace slag should be neither very. The mortar flow diameter decreased with increasing slag content, this means that the workability decreased with increasing slag content. It is a nonmetallic product, consisting of silicates and aluminosilicates of. This group of materials is characterized by high ductility in the range of 37%, tight crack width of around 60.
Ecc, short for engineered cementitious composites, is a class of ultra ductile fiber reinforced cementitious composites originally invented at the university of michigan in the early 1990s. In the case of steelmaking slag, the slag contains metal elements such as iron in oxide form, however because the refining time is short and the amount of limestone contained is large, a portion. Effect of blast furnace slag powder on compressive. The rapid cooling of molten slag by large quantities of water produces sandlike granule aggregate. Blast furnace slag as a concrete aggregate mf 1638 a. It is a recovered industrial byproduct of an iron blast furnace.
Granulated blast furnace slag has a cellular structure resulting from rapid quenching in water, is cementitious in nature, and sets to form a solid concretelike mass. Ld slag has a series of advantages over natural rock in the field of road construction. Such fact indicates a possibility to produce portland cement, since decrease the bofs basicity caosio2. The dust obtained from the lead baghouse assays about 5052 per cent lead and 2023 per cent zinc and is returned to the lead smelting system. Blast furnace slag is recovered by melting separation from blast furnaces that produce molten pig iron. However, this statement can be considered only partially correct. After solidi fication, cooling may be accelerated by applications. Supersulfated cement usually contains about 80% ground granulated blast furnace slag, 15% gypsum or anhydrite, and a small amount of portland clinker to act as an activator. When the metallurgical smelting process is complete, the lime in the flux has been chemically combined with the aluminates and silicates of the ore and coke ash to form a nonmetallic product called blast furnace slag.
Slag cement is commonly found in readymixed concrete, precast concrete, masonry, soil cement and high temperature resistant building products. The studied slag metal distributions were also showing strong, trendlike relationships, which was not affected by the operational status of the blast furnace during the studied sampling period. Blastfurnace slag cement article about blastfurnace slag. It is then processed and used for various iron and steel slag converter applications. A study on selected hotmetal and slag components for. Groundgranulated blast furnace slag is highly cementitious and high in csh calcium silicate hydrates which is a strength enhancing. Blast furnace slag concrete can be reliably pumped when the slag is supplied to the readymix production in a saturated condition.
Use and properties of blast furnace slag as a building. Effect of ground granulated blast furnace slag as partial. Granulated blast furnace slag is a glassy granular material that varies, depending on the chemical composition and method of production, from a coarse, popcornlike friable structure greater than 4. Other components of blast furnace slag include alumina alsub2o3 and. Ggbfs is divided into three classifications based on its activity index. The primary components of iron and steel slag are limestone cao and silica sio 2. The chemical composition of a slag varies considerably depending on the composition of the raw materials in the iron production process. Blast furnace slag consists principally of silicates and aluminosilicates of lime and other bases developed simultaneously with iron in a blast furnace. While there are many applications and benefits of slag cement, a few are highlighted below and detailed information sheets are located here.
Silicate and aluminate impurities from the ore and coke are combined in the blast furnace with a flux which lowers the viscosity of the slag. The latent hydraulic property of the blastfurnace slag gives excellent longterm strength. Grain size effect in elution test of electric arc furnace slag mdpi. Astm c989 c989m 18a standard specification for slag. The microprobe was a cameca camebax operating voltage of 15 kv and probe current of 3. As a product of calcinated fluxstone and the alumina and silica phases present in iron ore, the four major oxide phases present in acbfs are oxides of calcium cao, silica. A technical advisory group tag was set up to bring together representatives from the environment agency, wrap and industry. Hamazaki, properties of granulated blast furnace slag cement concrete, in proceedings of the fly ash, silica fume, slag, and natural pozzolans in concrete fourth international conference, istanbul, turkey, 1992.
Today, blast furnace slag is a saleable product granulated slag sand used as co 2 friendly substitute of clinker in cement production rather than a difficult and costly waste material. Solution compositions were measured from the very first minutes of. Jan 10, 2014 ld slag has a series of advantages over natural rock in the field of road construction. Ground granulated blast furnace slag is commonly used in combination with portland cement in concrete for many applications10,11 7. Approximately 290 kg of slag is generated for each ton of pig iron. With increase in silica activity in the range of 0. Appendix a contains a list of tag members and appendix b gives its terms of reference. The composition of the slag glass was determined by electron microprobe analysis of powder, embedded in resin, ground and polished flat. It is generally recognized that the rate of hardening of slag cement is somewhat slower than that of ordinary portland cement during the first 28 days but thereafter increases so that at 12 months the strengths become close to or even exceed those of. The ground granulated blast furnace slag is a byproduct of iron manufacturing industry. The majority of components in granulated blast furnace slag are various glassy metallic silicates iron, calcium, magnesium, aluminum, and titanium silicates, including. Today, blast furnace slag is a saleable product granulated slag sand used as co 2friendly substitute of clinker in cement production rather than a difficult and costly waste material. Microwave roasting of blast furnace slag for carbon dioxide.
Blastfurnace slag is the glassy granular material formed when molten blastfurnace slag is rapidly chilled, as by immersion in water virgalitte et al. Blastfurnace slag cement article about blastfurnace. Blastfurnace slag article about blastfurnace slag by. Significant influence for steel desulphurization has content of.
Characterization of basic oxygen furnace slag and granite waste. The blast furnace slag should be a freeflowing one at the operating temperatures to ensure efficient slag metal separation. Portland blastfurnace slag cement is a mixture of ordinary portland cement and not more than 65 wt. Slag handling is an important aspect of modern blast furnace operation. Effects of fineness and chemical composition of blast furnace. Rinse eyes thoroughly with water for at least 15 minutes, including under lids, to remove all particles. The composition of slag varies upon the type of furnace and charge, the desired grade of steel purity and the furnace operation conditions. Steel slag material description user guidelines for waste and. Ground granulated blast furnace slag ggbfs is designated in astm c 989 and consists mainly of silicates and aluminosilicates of calcium. In the same way as aircooled blast furnace slag, converter slag is cooled slowly by natural cooling and water spray in a cooling yard. The molten slag, which absorbs much of the sulfur from the charge, comprises about 20 percent by. Generally the products produced from this type of slag are known as air.
Use of aircooled blast furnace slag as coarse aggregate in. Nonportland cement activation of blast furnace slag. In this study, aluminosilicate glasses as models for blast furnace slag and. Effect of blast furnace slag powder on compressive strength. The blast furnace slag should be a freeflowing one at the operating temperatures to ensure efficient slagmetal separation. Properties of hardened concrete with blast furnace slag. The use of yield factors in the model raised the question if variation in hot metal and slag composition during and between taps exist. The samples were collected from seven steelmakers located. Iron is extracted from iron ore in a blast furnace by a process known as reduction. Asms then further process the blast furnace slag into useful products for the construction industry such as concrete aggregates and road base products. This paper studies the blast furnace slag glass phase structure by a series of analysis methods.
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