The chemical composition of a slag varies considerably depending on the composition of the raw materials in the iron production process. Mineralogical composition of lf slag depends on both. National slag collection the national slag collection is a resource primarily of interest to those engaged in researching early metallurgy through physical remains. Effect of refining slag phase composition on ladle furnace. Significant influence for steel desulphurization has content of. 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.
In the case of steelmaking slag, the slag contains metal elements such as iron in oxide form. My father used to keep a beautiful blue and white swirled rock as the centerpiece of his aquarium decor. Granulated blast furnace slag just like aircooled blast furnace slag, this slag has a hydraulic property and there is no risk of alkaliaggregate reaction. The influence order to lining corrosion and permeation are kinds of refractories, feo content, sio 2 mgo and basicity. It is the property of ironbridge gorge museum trust igmt and is subject to a memorandum of agreement between the trust and the historical metallurgy society. The effect of foamy slag in electric arc furnaces on electric energy consumption abstract in electric arc furnace steelmaking units, the essential parameters that considered important are reducing price, increasing production and decreasing environmental pollution. Electric arc furnaces are the largest users of electric energy in industry. The fineness of the slag does not show an obvious effect on. Slag is usually a mixture of metal oxides and silicon dioxide. The results show that after reconstruction, the freecao content of reconstructed steel slag rss is reduced. Because of the powerful latent hydraulic property that results from fine grinding, this slag is used in products such as portland blast furnace slag cement. Considering these various requirements, blast furnace operators can select a slag composition that maximizes profit and value in. After cooling from its molten state, steel slag is processed to remove all free metallics and sized into products. This action exposes fresh sites for further reaction and is supposedly responsible for enhanced slagmetal reaction rates, influencing the blast furnace operations and the quality of the metal.
Aluminachrome brick is the suitable refractory to freeze lining in submerged arc furnace. To realize the industrial application of online reconstruction technique of steel slag, a pilotscale reconstruction research of steel slag ss with electric arc furnace slag eafs and coal cinder cc and its mechanism were investigated. The strongest destructive effect on a lining is the chemical factor. Other components of blast furnace slag include alumina alsub2o3 and. The slag composition that has the minimum corrosion ability is obtained. Ladle furnace slag samples were prepared for eds analysis as follows.
Theyre white with varying hues of blue glass swirled in and stunning to look at. Slagtap furnace definition of slagtap furnace by merriam. The lf slag is a byproduct from further refining molten steel after coming out of a basic oxygen furnace bof or an electric arc furnace eaf. This is a small electricarc furnace with an 8 to 25megavoltampere transformer, three electrodes for arc heating, and the ladle acting as the furnace shellas shown in a in the figure. Slag tap furnace definition is a blast furnace or pulverizedfuel furnace with a tap opening in the bottom for removal of slag. Self compacting concrete mixtures with the use of ladle furnace slag as filler and steel fibers as reinforcement were produced and tested in the laboratory. Properties and uses of iron and steel slag mf 1826 national slag association. 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. After air cooling and weathering over several days, this material is completely ground into fine white particles. Furnace slag article about furnace slag by the free dictionary. Improving concrete and mortar using modified ash and slag. Influence of slag chemistry on the hydration of alkaliactivated blast. The initial increment in workability of concrete with the increase in induction furnace slag is attributed to the low water absorption characteristics of induction furnace slag.
Slag furnace definition of slag furnace by the free. The mortar flow diameter decreased with increasing slag content, this means that the workability decreased with increasing slag content. Such fact indicates a possibility to produce portland cement, since decrease the bofs basicity caosio2. The elemental composition of bf slag was investigated by xray fluorescence spectrometry xrf1800, shimadzu, japan, with a rh target used as the target. Making steel in the aristotle furnace lee sauder introduction the early presence of steel is usually explained as direct production from the bloomery, or long cementation in a hearth, or later, by crucible steelmaking. Different contents of ladle furnace slag filler, ranging from 60 to 120 kgm 3, and steel fibers, ranging from 0% to 0. Ground granulated blast furnace slag, for instance, is an industrial byproduct of iron refinement and is frequently used in concrete mixture design to not only. The slagrec project aims at realising a new system for slag recycling and also introducing it to the market through a mix of market preparation activities targeting electricarc furnace operators in europe. Argon or electromagnetic stirring is applied for better heat transfer. Optimum blast furnace slag composition for hot metal. Slag foaming in electric furnace steelmaking waseda.
Effect of highalumina ladle furnace slag as cement. After air cooling and weathering over several days, this material is completely ground into fine whi. The applications of many kinds of industrial byproducts, such as groundgranulated blast furnace slag, phosphorus slag, fly ash, and copper slag, in uhpc have been reported 3942. Page 5 granulated blast furnace slag is produced by quickly quenching chilling molten slag to produce a glassy, granular product. The effect of foamy slag in electric arc furnaces on. The results from the chemical analysis show that the approximate order of abundance of major components in ladle furnace slag is as follows. The use of the lf slag in further applications requires. The composition of slag varies upon the type of furnace and charge, the desired grade of steel purity and the furnace operation conditions. In general increasing the cao content of the slag results in raised slag basicity and an increase in compressive strength. Applications of steel slag powder and steel slag aggregate in ultrahigh performance concrete. Recycling of ladle furnace slags abstract ferrous industry slag is waste product of all steelmaking manufactures. Chemical composition of the ladle furnace slag has been determined using energy dispersive spectrometry eds. Blast furnace slag bfs and steel furnace slag sfs have a long history of being utilized as industrial byproducts, going back almost 100 years in the united states. However, slags can contain metal sulfides and elemental metals.
Blast furnace slag material description user guidelines for. Jul 22, 2011 my father used to keep a beautiful blue and white swirled rock as the centerpiece of his aquarium decor. During a steel treatment the chemical composition of slag is modified with other additions of slag making agents, and also by decreasing the contents of easily reducible oxides in order to create. The primary components of iron and steel slag are limestone cao and silica sio 2. 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 most common process is quenching with water, but air or a combination of air and water may be used.
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 ladle furnace slag samples was investigated by means of a several different analytical methods. A way to reduce environmental impact of ladle furnace slag. Calculationanalytical investigation of composition and high temperature properties of charge materials and properties of primary and final slag from blowingin burden during furnace shutdown is accomplished for jsc arselormittal kryvyy rih and jsc severstal with the use of monitoring and control system of slag mode of blastfurnace. Slag is the glasslike byproduct left over after a desired metal has been separated i. The chemical composition of slag is usually expressed in terms of simple.
The effect of chemical composition of blastfurnace slag on. 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. Jan 25, 2017 this period of furnace operation is known as the refining period, and its purposes are to reduce the oxides of iron and manganese in the slag and to form a calcium carbide slag, which is essential to the removal of sulfur from the metal the refining slag has approximately the following composition. It turns out its a piece of slag glass from a very old iron blast furnace. As the chemical composition and free lime fcao content of each batch of slag are significantly different, it is difficult to use the. This article provides results of studying the effect slag phase composition on chemical breakdown of a lfu. Coal bottom ashboiler slag material description user. Materials to be added to the steel melt directly before the end of the reheating process are not fully embedded in the slag structure, so they can be found in the slag as free oxides cao, mgo. Hydration mechanisms of activated blast furnace slag dora. The burnability of raw meal was determined by the linear shrinkage and free lime content of clinkers sintered at different temperatures. Characteristics and applications of iron and steel slag. Influence of slag chemistry on the hydration of alkaliactivated blastfurnace slag part ii.
Pilotscale reconstruction of steel slag with electric arc. Bfs is composed of the nonmetallic components removed from iron ore during processing in a blast furnace. One of these, as the representative sample sieved to particle size 0. Appendix a contains a list of tag members and appendix b gives its terms of reference. There is another simple, almost obvious way to increase the carbon content and decrease the slag content of bloom iron, that we. Physical, chemical, and crystalline characterizations were performed in order to verify. This period of furnace operation is known as the refining period, and its purposes are to reduce the oxides of iron and manganese in the slag and to form a calcium carbide slag, which is essential to the removal of sulfur from the metal the refining slag has approximately the following composition.
Behavior of self compacting concrete containing ladle furnace. Highalumina lfs has a better hydraulic reaction in mortars than highsilica lfs. Slag furnace definition of slag furnace by the free dictionary. In order to make a complete characterization of ladle furnace slag lf slag, lfs, as nonhazardous industrial waste, and to solve its permanent disposal andor recovery, bearing in mind both the. There is abundant literature on the subject of reuse and recycling of blast furnace bf, basic oxygen furnace bof, electric arc furnace eaf. Ladle furnace slag in construction journal of materials. Slag cement specifications are described and slag produced from european and north american blast furnaces are compared to the slag cement standards. 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 effect of foamy slag in electric arc furnaces on electric. Ladle furnace slag lfs is a nonuniform byproduct, and can be highalumina or highsilica slag. These slags are combined with any carryover of furnace slag and assist in absorbing. Ladle furnace slag in construction journal of materials in. Using the known chemical composition of the slag and the activator, the elemental concentrations in the pore solution as well as the hydrate assemblage can be. Blast furnace slag material description user guidelines.
Furnace slag is a crossword puzzle clue that we have spotted 1 time. 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. A technical advisory group tag was set up to bring together representatives from the environment agency, wrap and industry. I recently visited the brook where he found it and gathered a respectable amount of the same rocks. Ladle furnace slag lfs is a byproduct of a steel plant. Chemical composition of the ladle furnace slag has. The chemical composition varies depending on operating parameters and killing process. Table43 presents a chemical analysis of selected samples of bottom ash and boiler slag from different coal types and different regions. Characterization of basic oxygen furnace slag and granite waste. Slag furnace synonyms, slag furnace pronunciation, slag furnace translation, english dictionary definition of slag furnace.
Furnace slag article about furnace slag by the free. Ladle furnace reducing slag is a common byproduct in steelmaking of carbon and low alloy steels. Partial substitution of cement by lfs in amounts of 20% by weight has no negative effects. Study on the partial replacement of fine aggregate using. 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. Behavior of self compacting concrete containing ladle. The steel furnace slag or blended steel furnace slag can only be applied to land. The working layer of a ladle furnace unit lfu lining made from periclasegraphite refractory is most strongly subjected to the effect of corrosion factors that concern thermal, mechanical, and chemical action. Compositions of lf slags from various plants categorized based on alumina content are listed in table 3. There is abundant literature on the subject of reuse and recycling of blast furnacebf, basic oxygen furnacebof, electric arc furnaceeaf.
The composition of the bottom ash or boiler slag particles is controlled primarily by the source of the coal and not by the type of furnace. N2 in order to understand the effect of slag composition on foaming in an eaf, slag foaming was quantitatively studied for caosio2feo slags at temperatures ranging from 1,250 to 1,400c. Characterization of ladle furnace slag from carbon steel. The study on the use of blast furnace slag, steel slag and fly ash as raw materials to produce cement clinker has been carried out in the present investigation.
Analysis of slag flow in blast furnace during the extraction. Page 5 granulated blastfurnace slag is produced by quickly quenching chilling molten slag to produce a glassy, granular product. Slag foaming in electric furnace steelmaking waseda university. Slag is the collection of compounds that are removed. Many translated example sentences containing granulated blast furnace slag germanenglish dictionary and search engine for german translations. They showed that slag of the following composition 35% al 2 o 343. Most lf slags contain cao, mgo, sio 2, and al 2 o 3 as major constituents with minor quantities of feo, mno, p 2 o 5, and tio 2. Oxygen is blown into the furnace vessel through a watercooled oxygen lance oxidizing carbon and the other unwanted elements in the molten iron. Cao, sio 2, al 2 o 3, mgo, feo, mno, cr 2 o 3, p 2 o 5, tio 2, k 2 o and na 2 o.
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. Slagtap furnace definition is a blast furnace or pulverizedfuel furnace with a tap opening in the bottom for removal of slag. Pdf a way to reduce environmental impact of ladle furnace slag. Groundgranulated blast furnace slag is highly cementitious and high in csh calcium silicate hydrates which is a strength enhancing. Because of the disputes over the composition of the cement, the manufacturers of cements containing blast furnace slag founded the association of german iron. The use of concrete and mortar containing coal fly ash, blast furnace slag, and other dispersed technogenic materials is one of the major areas of potential resource savings and improving the environmental efficiency and sustainability of construction. Grinding reduces the particle size to cement fineness. Steel slag material description user guidelines for waste and.
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. The chemical composition of a slag varies considerably depending on the composition of the raw materials in the. Utilization of blast furnace slag, steel slag in the. Blast furnace control using slag viscosities and liquidus.
The main components of blast furnace slag are cao 3050%, sio 2 2838%, al 2o 3 824%, and mgo 118%. Recycling ladle furnace slag as flux in steelmaking. The different mixtures were tested in the fresh state. A promising type of steel slag for applications is the ladle furnace lf slag, which is also known as the basic slag, the reducing slag, the white slag, and the secondary refining slag. During a steel treatment the chemical composition of slag is modified with other additions of slagmaking agents, and also by decreasing. Significant influence for steel desulphurization has content of easily reducible oxides in slag. The microstructrue and properties of raw meal and clinker were investigated by the means of. 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.