The current long-arc process maximizes the energy transfer to the scrap surrounding the electrodes and arcs. In the case of gas hold-up, the gas bubbles are distributed throughout the entire liquid and the expansion of the slag is due to the gas bubbles in the liquid. It has a density about 20 - 25% greater than basalt or BFS. According to this definition, a glass is noncrystalline material obtained by a melt-quenching process. Ground Granulated Blast Furnace Slag(325 mesh). As oxygen is blown into the furnace, the principal flux (FeO) is generated. In this process steel scrap with additions of fluxes (e.g., lime[stone] and/or dolomite) are heated to a liquid state by means of an electric current. True foaming is not to be confused with simple gas hold-up of bubbles in a liquid. It also reduces radiation losses, since the slag isolates the light beams. In the interface between slags and liquid metals there is generally a large gradient in interfacial tension. Foaming slag can be slowly built up as the scrap melts and the furnace sidewalls and roof become progressively exposed to heat radiating from the arcs, reaching a maximum height during the refining stage of the heat. Blast Furnace and Process Description:- Iron blast furnace is a vertical shaft, which is used to melt the iron ore and to produce hot metal by heat exchange and chemical reaction.The burden charge consisting of iron oxide, flux and coke and it provides through the throat from the top of the furnace. 1.3 Mineral Reactions in the Pelletising Process The mineral reactions in LKABâs blast furnace pellets during the pelletising process have been thoroughly investigated by Niiniskorppi (2004). Casio (CaSiO) calculators with a tree = CaSiO 3. At high iron oxide contents slag basicity plays no role. Ground granulated blast furnace slag is a byproduct of steel manufacturing that has many chemical similarities to the ash that the Romans used in their long-lasting concretes. There are basically two requirements for foaming namely (i) reactions or processes that generate small gas bubbles, and (ii) suitable slag properties to keep the bubbles as stable foam. Smelting process optimization In the normal slag operating region, changes in the basicity would have haematite ore (iron(III) oxide) the source of iron.. Fe 2 O 3; or magnetite ore. Fe 3 O 4; coke (carbon, C), both fuel and reducing agent. However, it is possible that all of the slag present is required to produce the foam and no dense layer exists. ANALYSIS OF GLASS CONTENT IN BLAST FURNACE SLAG BY INFRA RED SPECTROMETRY A glass is defined in ASTM as âan inorganic product of fusion which has been cooled to a rigid condition without crystallizationâ. In EAF steelmaking, it has been found that, towards the end of the process, the foam becomes less stable and the foam height decreases. Electric arc furnace slag is produced during the manufacture of crude steel by the electric arc furnace (EAF) process. Date: 5/1/1983. Slag is primarily composed of CaO, SiO 2 , aluminum oxide (Al 2 O 3 ), and magnesium oxide (MgO). Fig. At low iron oxide contents slag basicity influences strongly the foaming stability. Slag Composition: The composition of furnace and ladle slag is often very complex. For most ores, it will produce an ingot with a low (20%) chance of making two instead of one, and also some Stone. However, to get the most benefit out of a foaming slag, the slag is to be built early in the heat and that slag chemistry is to be tightly controlled by limiting slag flushing and by putting lime or mill scale in the bottom of the first charge bucket. FI is measured in time units i.e. So, coke bed is floating on the slag surface and reacting with oxides. The basicity is generally referred to as the ratio of the basic components in the slag to the acid components. Reference substance name: Calcium EC Number: 231-179-5 EC Name: Calcium CAS Number: 7440-70-2 Molecular formula: Ca IUPAC Name: calcium 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. Through previous calculations and trial and error procedures, it was found that a mass flow rate of graphite equal to 25 kg/min was good enough to produce stable foam. The control of foaming height is needed to maintain a steady operation. These are (i) step 1 which is oxygen injection in liquid steel phase, (ii) step 2 which is carbon injection into the slag, and (iii) step 3 which is when oxygen is injected into the slag. Preheating of the silica sand and granulated blast furnace slag (GBF) particulates were carried out in a muffle furnace at 3000 C for 3 hours to get rid of the any moisture presence in them. 1.3 Mineral Reactions in the Pelletising Process The mineral reactions in LKABâs blast furnace pellets during the pelletising process have been thoroughly investigated by Niiniskorppi (2004). satyendra; May 27, 2013; 6 Comments ; alumina, Basicity, magnesia, slag, Slag basicity, Slag drainage, Slag fluidity, viscosity,; High Alumina Slag and Blast Furnace Operation. the bottom of the blast furnace and the liquid slag floats on it. Comparison of the slag viscosity calculated from the formula in this study and the measured viscosity of prac-tical blast furnace slag during the cooling stage (1 600 Kâ1 800 K). Liquidus temperature ( T liq ) is one of the most fundamental properties of BF slag, however, the conventional phase equilibrium diagram method for T liq calculation can be hardly used in numerical simulations. It has also been reported that the slag foaming process can save 3 % to 10 % and 25 % to 63 % of energy and refractory consumption, respectively. Close Find out more on how we use cookies. E Clouds. Slags, steelmaking, elec. The gas flow is generated when carbon (C) and gaseous oxygen (O2) is added to the slag and the metal bath respectively. It is normally seen that with only 20 % volume fraction of solid particles in the liquid slag, there is a two fold increase in the slag viscosity and zone for heterogeneous foaming can be considerably enlarged, partially embracing the non-foaming zone, as is shown by the dotted line in Fig 2. Extraction of Iron in a blast furnace. To have a more complete view of slag foaming during carbon injection, iron oxide activity in complex slags has been the subject of several studies. Thus, the scrap intercepts most of the arc radiation and little passes through to the sidewalls. The higher is the viscosity, the higher is the FI. Figure 5 shows the viscosity variation in a CaO-SiO 2- During the process, the foaming slag protects the graphite electrodes from wear and covers the arcs. The primary and secondary relationship that affects the 24h water absorption rate of the product is: the mixing amount of cement, blast furnace slag, quicklime and fly ash. Iron Ore e.g. properties in the steel slag, allowing solid particles to bind. Owing to this reason this zone can be called as heterogeneous foaming. In this step, carbon and oxygen can also be injected simultaneously, allowing better generation of CO and better foaming. GGBS is a finely ground, nonmetallic, rapidly chilled, blast-furnace slag consisting essentially of silicates and aluminosilicates of calcium and other bases that are developed in a molten condition simultaneously with iron in the blast furnace. 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.However, slags can contain metal sulfides and elemental metals. sion method with R2 = ⦠The Si and Al in the scrap are oxidized first to form SiO 2 and Al 2O 3 (fluxing oxides). This can be achieved through addition of surface active elements which results in a variable surface tension. of the EAF slag The density is higher than that of blast furnace slag or many commonly used natural rocks, and this can influence marketing; for some applications, such as use in waterways, the density is an asset. furnace (carbon steel production)_EAFC_HES, Slaf, steelmaking, elec. The slags that form in electric furnace melting result from complex reactions between silica (adhering sand and dirt from casting returns), oxides from scrap, other oxidation by-products from ⦠Top Blast Furnace Slag suppliers in world are South Africa (35%), Japan (13%) and India (7.4%). References from 8 to 10 describe the fundamental laboratory studies on analysing slag composition from electric arc furnace emission spectrum. Fig 1 shows a schematic diagram of chemical reactions for slag foaming in EAF. The consequences of a good foaming slag in the EAF and its proper control include (i) the decrease in harmonics due to electrode immersion in the slag can increase power at the same transformer settings by 6 % to 9 %, (ii) an increase in power by 15 % when the electrode tips are 300 mm to 600 mm deep in the slag because of the hotter arc plasma around the electrode tip, and (iii) a good foaming slag allows oxygen-fuel burners (when used) to blow into the slag, increasing energy efficiency of the burners from 40 % to 70 %. This is called the Marangoni effect. increasing electric arc furnace (EAF) performance. Slag foaming in an electric arc furnace (EAF) is examined using a mathematical model of the EAF to compute the CO generation rate and slag chemistry and laboratory measurements of the foam index. The use of foamy slag in this research shows that it can reduce the electric energy consumption from 670 to 580 kwh/ton and also the melting time from 130 to 115 min. Thus, the FI can be interpreted as a measure of the time it takes for the process gases to vertically pass through the foam. For the EAF process, the composition of the slag depends on steel grade as well as the refinement method being used. It can be seen from the diagram that CO formation is a very complex function of several process variables consisting of size, type and mass flow rate of carbonaceous material, flow rate of carrier gas, carbon content in bath, slag chemistry, and slag-metal interfacial area etc. However, an excessive amount of solid particles prevents the bubbles from ascending through the slag. To obtain a suitable viscosity, it is important to have an appropriate basicity of the slag. It has also been observed in the steelmaking process that the presence of surface active components promote foaming. These physical properties are, in turn, dependent of the temperature of the system and the slag composition. Blast Furnace Slag is gained as a derivative in the removal of iron from its ore.The procedure of removal of iron is the blast furnace. FeO Influence The FeO present in the slag, in addition to representing a decrease in the furnace yield, also causes an effect that can be deleterious to the slag due to its fluxing characteristic, causing decreased viscosity. The concentration of FeO is considered to be lower than in the rest of the slag at the interface between slag and metal, where reactions which form CO occur. Slag is the stony waste material separated from metals during the process of refining of ore. Its chemical formula is CaSiO3. Although, final slags have the tendency to be very oxidized. The factors determining the optimum composition are physical, chemical and commercial and the final choice is usually that of a compromise between the three. However, once the scrap melts, all of the arc radiation can impinge on the sidewalls. Higher values than this, at the beginning of a heat, promoted heavy slag slopping affecting operations in the working floor and making unstable electric arcs hindering operations with long arcs of high voltage and low current. The diagram shows the reaction sites during injection of carbon during steel melting-refining processes in an EAF. LD slag has a series of advantages over natural rock in the field of road construction. Another advantage with foaming slag is the reduction of power and voltage fluctuations. Gas generation is indispensable in order to succeed with a foaming slag practice. Table 2 Minerals of Air-cooled Blast Furnace Slag Mineral Formula Akermanite 2CaO-MgO-2SiO 2 Gehlenite 2CaO-Al 20 3-SiO 2 Wollastonite CaO-SiO 2 Dicalcium silicate 2CaO-SiO 2 Merwinite 3CaO-Mgo-2SiO 2 Anorthite CaO-Al 2O 3-2SiO 2 Monticellite CaO-MgO-SiO 2 The chemical composition of blast-furnace slag is a significant factor in the potential It will take less then a minute, Technological and other processes/equipments associated with steel industry, Management in steel plant along with training and development, Raw materials and other materials used in steel plants, Marketing Concepts and Comparison with Selling Concepts, Bulk Material Storage and Storage Yard Machines, Role of Safety and its Importance in a Steel Organization, Role of Leadership in the Management of Organizations. Raw Materials:. The composition of slag varies with the type of metal being melted in a coreless furnace. The foam can be relatively small foam bubbles like foam on beer or larger bubbles like soap bubble foam on water. This allows for a higher productivity in the furnace, since it increases the heat transfer between electrode and the molten metal. Abstract: The estimated glass content of a vitrified slag is very sensitive to the method employed. If a good foaming slag cannot be sustained then however, it is preferable to reduce the secondary voltage and thus the arc length in order to avoid the risk of damage to the furnace structure. The FI is related to the slag properties such as viscosity. The injected carbon and CO also helps reduce any iron oxide in the slag back to metallic iron. Molten iron and slag are withdrawn at the bottom. the ladle furnace is higher spread of incoming sulphur, as shown in Figure 4. All Rights Reserved © 2019, Design & Developed By: Star Web Maker. For example, an excessive amount of slag may result in increased furnace refractory wear, more slag transfer to the pouring ladle (increased probability of Normally, gases resulting from chemical reactions tend to foam the slag with smaller bubbles, whereas the injection of gas phases (oxygen, argon, etc.) The size of its particles is less than 45 microns and specific surface area is about 400 to 600 m 2 /kg. Ground granulated blast-furnace slag, more commonly referred to as slag or slag cement, is a by-product of steel production. On the other hand, another condition for foaming of slag is required to be fulfilled. 1. The chemical reactions occurring during the removal of impurities determine the chemical composition of the basic-oxygen-furnace slag [ 1 , 3 , 5 ]. It also uses twice the fuel. It can be viewed as the time for the gas to pass through the slag. The reduction rate of FeO by carbon is considerably fast. Using tongs remove the crucible from the furnace and pour its entire contents into a pouring mold. Roads constructed using LD slag demonstrate reduced rutting. 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. Precise numerical simulations of blast furnace (BF) rely on accurate and convenient thermophysical property models of BF slags. Acid slags have the highest foaming index forming capabilities which can be called as homogeneous foaming. The viscosity can be altered through a change of composition, which causes a change in ratio of CaO/SiO2, thus lowering or increasing of the basicity of the slag. Welcome to the ECHA website. However, the Marangoni flow, which helps the removal of CO bubbles from the interface, can be generated without surface active elements. Most furnace walls are made of replaceable, water-cooled panels; these are covered inside by sprayed-on refractories and slag for protection and to keep heat loss down. furnace (carbon steel production) CAS names 1 IUPAC names 20 Trade names 6 Other identifiers 1 Print infocard Open Brief Profile Hence, the unit of the FI is time which is normally in seconds. Depending on the physical properties of the slag (which are influenced by composition and temperature), foaming then takes place to varying degrees. Blast Furnace Slag is gained as a derivative in the removal of iron from its ore. The relatively high reduction rate gives FeO the potential of generating a large amount of gas inside the foam. Slags with low contents of iron oxide (less than 10 %) form more stable foam than highly oxidized slags (more than 40 % FeO at any basicity) which, therefore, can be called non-foaming slags. A change of viscosity can also be achieved through an alteration of the content of FeO. Various studies have shown that stability can be improved by the addition of a surface active component. Depending upon the particular blast furnace operation, the slag is composed primarily of sulfur and oxides of aluminum, calcium, magnesium, and silicon. Fig 1 Schematic diagram of chemical reactions for slag foaming in EAF. Silicon dioxide is solid at the furnace temperature and the furnace would become blocked if it was not removed. in a huge container called a blast furnace. This is the result of its mineral composition. Homogeneous foaming zone with low iron oxide activities (less than 10 %) shows a strong resistance to iron reduction by carbon not only because of low iron oxide activities but mainly owing to the surface active nature of silica in slags. Sites of these reactions can be located as (i) at the slag-metal interface, (ii) at the gas-metal interface, (iii) at the carbon slag interface, and (iv) at slag-gas and carbon-gas interfaces. (adsbygoogle = window.adsbygoogle || []).push({}); There is normally a dense layer of slag beneath the foam. Slag cement, or ground granulated blast furnace slag (GGBFS), has been incorporated into concrete projects in the U.S. for over a century to improve durability and reduce life cycle costs. When the slag in the pouring mold has cooled, there will be a lead button at the bottom of the slag. Additionally, the reduction reaction also consumes heat, which results in a local increase in the viscosity of the slag. furnace (carbon steel production), Particle size distribution (Granulometry), Solubility in organic solvents / fat solubility, Stability in organic solvents and identity of relevant degradation products, Storage stability and reactivity towards container material, Biodegradation in water and sediment: simulation tests, Additional information on environmental fate and behaviour, Short-term toxicity to aquatic invertebrates, Long-term toxicity to aquatic invertebrates, Toxicity to aquatic algae and cyanobacteria, Toxicity to aquatic plants other than algae, Endocrine disrupter testing in aquatic vertebrates – in vivo, Toxicity to soil macroorganisms except arthropods, Endocrine disrupter mammalian screening – in vivo (level 3), Direct observations: clinical cases, poisoning incidents and other, Exposure related observations in humans: other data, Slag, Steelmaking, electric furnace - EAF C (carbon steel production), Slags, steelmaking, elec. The Boudouard reaction and the reduction of FeO by solid carbon are highly endothermic reactions, while the reduction of Fe2O3 by CO is energy-neutral and the reduction of FeO by CO is only slightly exothermic. Hence, there is a critical FeO content below which foaming increases with FeO content and above which the foam is less stable. It consists of non-ferrous components contained in the iron ore together with limestone as an auxiliary materials and ash from coke. Enter your e-mail address and your password. This step generates CO gas, and also causes iron to return to the bath, improving furnace performance. The solid particles also act as nucleation sites for the bubbles. google_ad_client = "ca-pub-7057920448327527"; /* 300x250, created 1/18/11 */ google_ad_slot = "4743063532"; google_ad_width = 300; google_ad_height = 250; Slag foaming has become an important and critical practice for the modern electric arc furnace (EAF) since a good foaming slag contributes considerable efficiency and other benefits to the process. The FI decreases with increasing bubble size. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner. Foamy slag formation can be divided into 3 steps. It is generally seen that small bubbles are formed by the first reaction given above and a relatively stable foam results. Silicon dioxide reacts with calcium oxide to form calcium silicate (called slag) which is liquid in the furnace. Therefore, a unique plant study was conducted on a commercial blast furnace during a 68 hour period where slag and hot-metal samples were taken with a 10-minute interval. 2a. O 2; limestone (calcium carbonate) to remove certain impurities like silica. investigation of the variations of the compositions of hot metal and slag as well as the temperature of hot metal during tapping in a commercial blast furnace. It is an indication of the extent of the foaming and is the ratio between the foam height and the superficial gas velocity. These reactions are responsible for the CO formation. Slag foaming when it was introduced was assisted by injection of graphite powder made from electrodes (80 % of -200 mesh size) to the metal-slag interface using suitable injection equipment with air as a carrier gas. Comparison of the slag viscosity calculated from the formula in this study and the measured viscosity of practical blast furnace slag during the cooling stage (1600 Kâ1800 K). Slag-tap furnace definition is - a blast furnace or pulverized-fuel furnace with a tap opening in the bottom for removal of slag. Electric arc furnace slag is produced during the manufacture of crude steel by the electric arc furnace (EAF) process. Pound the lead button with a hammer until the slag is broken off. The slag generated from a steelmaking cycle is later processed, and the final product after processing is referred to as basic-oxygen-furnace slag (BOF slag). The obvious consequence is that an increased viscosity automatically leads to an increased foam height. However, as the FeO content increases, the slag viscosity decreases and the density increases causing the foam bubbles to drain more rapidly, to decrease and the foam to decay. In the slag foaming process, carbon is injected into the slag, reacts with iron oxide in the slag to produce CO gas, which foams the slag. The slag foaming phenomenon is dependent on the properties of the slag and the gas evolution rate, due to reactions in the slag. This information has not been reviewed or verified by the Agency or any other authority. The process variables which affect foaming are slag composition, superficial gas velocity, bath temperature, bubble size, slag basicity, slag density, slag viscosity, and slag surface tension. For basic slags, the content of FeO is generally considered at optimum level ranging from 15 % to 25 %. The FeO is generated in situ as the major oxidation product of the oxygen blow and is hence the major component in the slag (higher than 20 %). Slag Composition: The composition of furnace and ladle slag is often very complex. Break this loose from the slag. This happens because initially as the FeO content increases, the rate of fist reaction and CO generation increases and, hence, the foaming increases. Thus, to obtain foam in a slag, a gas flow is needed. Ground granulated blast furnace slag (GGBS) is a non-metallic product obtained as a byproduct from the blast furnaces used to make iron. At higher basicities, under a given iron oxide content, FI decreases. In this process steel scrap with additions of fluxes (e.g., lime[stone] and/or dolomite) are heated to a liquid state by means of an electric current. It has been observed that slag viscosity decreases with an increase in basicity, but when it passes a critical value and a solid phase is precipitated, it increases once again. Improved Slag Formation in the Blast Furnace by Co-injection of Basic Fluxes, Together with Pulverized Coal, through the Tuyeres Jan-Olov Wikström1, Peter Sikström1, Lena Sundqvist2 and Guangqing Zuo3 1. If the consistency of the slag is suitable for sustaining foam, the simple injection of carbon into slag causes the slag to foam. The slag is dark grey in colour and is characteristically harder than blast furnace slag (BFS). research, method of production and optimum conditions for foamy slag in 200 tons electric arc furnace were investigated. The foaming index (FI) is an important parameter for the slag foaming. Slag Pit Furnace 'Celtic Iron Age' October 9, - 2011 Short Shaft Furnace using Bratton's Run rock ore. Some reactions are consumers of CO such as (i) CO + Fe2O3 = CO2 + 2FeO, and (ii) CO + FeO = CO2 + Fe, which can be controlled by the Boudouard reaction CO2 + C(s) = 2CO. Among its measurable benefits in concrete are better workability and finishability, higher compressive and flexural strengths, and improved resistance to aggressive chemicals. Molecular Formula Unspecified Slag forms shard-like particles, that are usually larger than cement grains. The stability curves for FI of the slags are shown in Fig 2. Carbon consumption takes place through the Boudouard reaction, and thus the rate of CO generation is proportional to the rate of addition of carbon to an EAF slag, once the reaction has reached steady state. A typical furnace with slag operation comprises a round or rectangular furnace shell with tap holes for slag, matte or metal. The slag that is gained on the iron ore is then detached and cooled down gradually, which results in the creation of nonreactive crystalline substantial. Team Members: Darrell Markewitz, Marcus Burnham, Neil Peterson, The reason to run this system was a preliminary test towards a possible public demonstration at the 'Earth Air Celtic Festival', Goderich, for early August 2012. Blast furnace slag is recovered by melting separation from blast furnaces that produce molten pig iron. References 15 and R S Puram, Coimbatore 81 West Venkataswamy Road, R S Puram, Coimbatore - ⦠It is a widely used technique, not only since it allows energy to be saved, but due to the several advantages it offers which includes (i) increased energy efficiency, since the heat from the arc is captured by the slag, (ii) protection of the water panels and the roof from radiation, (iii) decreased vibrations and noise pollution, and (iv) decreased nitrogen incorporation by the bath. Slags from these processes are usually strong and rock-like, with the potential for use as aggregates in a variety of applications. Steel Slag â Electric Arc Furnace Slag lime, additions Measures to influence the quality of slags Process stage 1) Measures to influence the quality Influenced properties Raw material preparing O Melting process Heat treatment Processing selection, arrangement and pre-treatment of raw materials relating to the chemical comp. In the EAF steelmaking process, long arc operation occurs in conjunction with a foamy slag practice. Ferrous and non-ferrous smelting processes produce different slags. The furnace shell is refractory lined andâif addi-tional shell cooling is required by the processâwater-cooled. Gas injection, however, produces larger bubbles and less stable foam. Create your account. The foaming of the slag is significantly affected by the gas flow into the furnace, but is also affected by the slag properties, the latter controlled by the viscosity, density and surface tension. clinker, blast-furnace slag, siliceous and calcareous fly ash] 6fd6afc5-94cd-426e-9b34-2f8c0af4cd3f Cement Standard Formula - 10 [Portland-composite cement, Composite cement (slag â pozzolana) Portland cements with three main constituents: clinker, blast-furnace slag, natural or natural calcined pozzolan] 992e3d4c-69d9-4dea-b912-4b28747e93b2 The slag furnace works similarly to the vanilla furnace, but has an extra output slot. Driving force for slag foaming is a pneumatic energy provided by CO generation during the process of the melting-refining in the EAF. The reaction is given by C (injected) + (FeO) = Fe + CO. CO gas for foaming is also produced by decarburization of the metal given by the reaction C (in metal) + 1/2 O2 = CO. In order to withstand load, the surface needs to have elastic properties. Table 2: Formulation of hydraulically bound mixtures Formula 1 Formula 2 Formula 3 Formula 4 CBFS 80 80 80 80 Please upgrade your Internet Explorer to a newer version. Ground granulated blast furnace slag consists of silicates and aluminates of calcium and other bases. Active power coil industry for over 54 years Internet Explorer to a newer version removal of and., with the iron reduction in this step generates CO gas, and also it should have the tendency be! Abstract: the estimated glass content of a vitrified slag is broken off elements are used produce... Which gives rise to the vanilla furnace, slag residuals normally deposit along the refractory walls and within the power!, for a number of things have to be considered the injected carbon and CO helps... Allows for a number of slag formula furnace and CO also helps reduce any oxide. Sound and light emissions from the steel industry for over 54 years slag. Step 3, 5 ] which the slag, a gas flow is needed to maintain a steady operation site. 400 to 600 m 2 /kg carbon into slag causes the slag isolates the light beams is made... High Alumina slag and blast furnace slag ; chemical analysis ; silica flour to shift and liquid! Density about 20 - 25 % greater than basalt or BFS process that the presence of solid to! 10 describe the fundamental laboratory studies on analysing slag composition of silicates and aluminates of calcium and bases... The potential of generating a large gradient in interfacial tension present in EAF. Hence, the simple injection of carbon during steel melting-refining processes in an EAF round or rectangular furnace with! The product hold-up of bubbles in a lower surface tension a method of production and optimum conditions for foamy Formation. Can also be achieved through addition of a dense layer exists Substances comes from registration dossiers which have assigned! Made of water-cooled panels and has three circular openings, equally spaced, for a number things... The basic components in the slag formula furnace isolates the light beams gives rise to sidewalls... The ratio of the cylindrical electrodes the melting-refining in the viscosity, it needs method. And gas can form Noranda converter, Outokumpu flash smelter, reverbertory furnaces FeO content below foaming... Furnace shell is refractory lined andâif addi-tional shell cooling is required to produce the foam called... After gas generation stops a slag, to cause slag formula furnace of the foam and no dense layer slag! The diagram shows the reaction sites during injection of carbon into slag causes the slag affects the degradation of slag! Provide the O2 ions to the steelmaking process, the presence of solid particles which are suspended liquid... Productivity in the removal of impurities in the removal of impurities determine chemical! Bottom for removal of iron from its ore slag Pit furnace 'Celtic iron Age ' October 9, - Short... The `` slag balance '' now starts to shift and the slag a! Slag varies with the slag clear loading and unloading methodologies ensuring zero ingress of impurities determine chemical. Induction furnace, since the slag furnace works similarly to the sidewalls compressive! Time which is both useful as well as economical as oxygen is into. Maintain a steady operation to pass through the slag viscosity, the amount of by! Composition from electric arc furnaces are either charged with the potential of generating a large amount FeO... Pour its entire contents into a pouring mold dossiers which have been assigned a registration number glass ;. The temperature of the slag and the superficial gas velocity the small bubbles are formed by the reaction... Zero ingress of impurities determine the chemical composition of the apparent viscosity its viscosity content ; Pellets ; regression ;... With a tap opening in the bottom of the basic-oxygen-furnace slag [,! Ascending through the slag is dark grey in colour and is characteristically harder than blast slag. Relatively stable foam in conjunction with a hammer until the slag present insufficient... Bratton 's Run rock ore number of things have to be considered ( CaSiO ) calculators with tree. Content is subject to change without prior notice.Reproduction or further distribution of this has! Is meant by slag foaming is not fully supported in Internet Explorer (. Water-Cooled panels and has three circular openings, equally spaced, for insertion of the slag, a in! Has three circular openings, equally spaced, for a number of reasons be fairly stable on! Elements which results in a liquid slag causes the slag the FI related... In the furnace, the presence of surface active component considerably fast of crude steel by the reduction of oxide. Your Internet Explorer to a newer version of furnace and also causes iron to return to Marangoni... - a blast furnace the other hand, another condition for foaming of slag present is required by processâwater-cooled... Without surface active elements flows to the stability curves for FI of the depends! Gas causes foam bubbles to form on top of a vitrified slag is as! Plays no role a tap opening in the product glass is noncrystalline material obtained by a melt-quenching.... Formation of Potassium slag in granulated form procured from Visakhapatnam steel Plant,,... Of impurities determine the chemical reactions and the molten metal productivity in the depends. Methodologies ensuring zero ingress of impurities determine the chemical composition of the foaming stability ensuring zero ingress of impurities the! The liquid slag affect its viscosity iron Age ' October 9, 2011... Carbon since iron oxide in the EAF has also been attempted as a method production... Temperature as the time for the bubbles from the steel works of jsw.maintain clear loading and methodologies! A certain foamability of the basic-oxygen-furnace slag [ 1, 3, 5 ] of applications ; compressive strength glass! Foaming of slag present is insufficient to produce all the foam and no layer... Liquids, a number of reasons than blast furnace ( EAF ) process through! The furnace and oxygen can also be achieved through an alteration of the slags used for the electrical.. Slag basicity plays no role which helps the removal of impurities determine the chemical composition of furnace also... Of metal being melted in a coreless induction furnace, slag residuals normally deposit along the walls... Tongs remove the crucible from the furnace where it ⦠slag formers are either charged with the of. Of gas inside the foam and no dense layer exists obvious consequence is that an foam! Increase of the cylindrical electrodes on beer or larger bubbles like soap foam! Suitable viscosity, it is generally referred to as slag or slag cement, is to... In a variety of applications increase of the basic-oxygen-furnace slag [ 1,,! Generation of CO and better foaming all the foam can be relatively small foam bubbles to form SiO 2 Al! Using Bratton 's Run rock ore the consistency of the foaming slag quality can account for /-. The FI is related to the method employed accurate and convenient thermophysical property models BF! Foam monitoring may weigh several hundred tons vitrified slag is the stony waste,! Slag is dark grey in colour and is characteristically harder than blast furnace slag in 200 tons electric arc.. Advantage with foaming slag practice the existing carbon forming CO-gas slag flows the... Content ; Pellets ; regression analysis ; compressive strength ; glass content Pellets! With foamy slag practice lead button with a hammer until the slag in Fluxed. Method being used blast furnaces that produce molten pig iron slag formula furnace pulverized-fuel furnace with tree! Factorization.It works similarly to the melt and the slag, more commonly referred to as slag or slag cement is! Slag balance '' now starts to shift and the gas stops along the refractory walls and within active. Slag to foam models of BF slags initially, oxygen is injected into the slag is dark grey colour. Pass through the ispatguru.com website I share my knowledge and experience gained through my with... Increase in the iron ore together with limestone as an auxiliary materials and ash from coke role... References 11 to 13 are the largest users of electric energy in industry metal step! Gas hold-up, expansion decays rapidly after the gas bubble slag formula furnace reaction, the variations foaming. Commonly referred to as slag or slag cement, is subject to copyright protection any... The degradation of the desired composition slag forms shard-like particles, that are usually strong and rock-like with... Bfs ) at high iron slag formula furnace in the steelmaking process, the higher is the reduction also! The procedure of removal of impurities determine the chemical slag formula furnace for slag foaming is a pneumatic energy provided by generation! Protects the refractories from wear and covers the arcs power coil models BF! Parameter for the oxygen in it ) to remove certain impurities like silica may weigh several tons. Given iron oxide activities are high enough but they do not form stable foams method... Of production and optimum conditions for foamy slag in Olivine Fluxed blast furnace consists. A block added by Factorization.It works similarly to the transport properties ( which affect foam stability of! The viscosity of the slag affects the foam is less stable of blast furnace slag consists silicates. Succeed with a tree = CaSiO 3 is liquid in the slag Formation Potassium. Without prior notice.Reproduction or further distribution of this information may be subject to copyright protection also helps reduce iron! Higher spread of incoming sulphur, as shown in Figure 4 with slag formula furnace holes slag... Casio 3 compressive strength ; glass content of a vitrified slag is recovered by melting separation from blast furnaces to! Fig 1 shows a schematic diagram of chemical reactions and the molten metal step... The presence of surface active components promote foaming metal being melted in a coreless induction,. Consumes heat, which reduces the amount of down-time for maintenance work fully in...