The largest demand for blast furnace slag is cement. Blast furnace slag is a secondary aggregate used widely in construction because of its performance attributes and durability. The latent hydraulic property of the blast-furnace slag gives excellent long-term strength. Using granulated blast furnace slag can save energy by 20-40%, reduce costs by 10-30%, and reduce CO2 emissions by 44%. The first granulation facility in the U.S. to make a separate slag cement product was Sparrows Point, Maryland, in the early 1980’s. The first United States production was in 1896. This product is usually intended to be used in concrete either as an element of composite cement such as Blast furnace Cement/High Slag Blast Furnace Cement or as a straight addition to the concrete mix by the concrete producer. The length of the first bin can be shortened to 2.6m and the second increased to 3.9m to enhance the grinding capacity of the ball mill. Slag cement, often called ground granulated blast-furnace slag (GGBFS), is one of the most consistent cementitious materials used in concrete. Molten slag is tapped from a blast furnace, rapidly quenched with water ("granulated"), dried and ground to a fine powder. The roller crusher is suitable equipment for crushing blast furnace slag, which mainly depends on the extrusion between two rollers to realize the crushing of materials. The product is now widely available east of the Rockies. By using granulated blast furnace slag, it improves harvest quantities and flavor by improving photosynthesis, reducing blight on lower leaves, preventing rice blast and promoting ripening. In addition to being used as the base material, it is also used as aggregate for asphalt mixture due to its excellent hardness and wear resistance. It produces a lightweight aggregate that can be used for concrete masonry, lightweight fill, or can be ground into a cementitious product. BFS is typically a grey vesicular material that is lighter than most basalt. Chat with engineers here. Slag cement is normally used in proportions from 25 to 50 percent in structural and general concrete applications; the higher the amount of slag, the lighter the concrete. The heart of the process is the blast furnace that refines iron ore into iron. 3-5), also called slag cement, is made from iron blast-furnace slag; it is a nonmetallic hydraulic cement consisting essentially of sili-cates and aluminosilicates of calcium developed in a molten condition simultaneously with iron in a blast furnace. Concrete made of BFS aggregates can be pumped, placed and refined successfully. Quality situation of ground granulated blast furnace slag (GGBFS) produced: The value of the specific surface area of the slag powder produced by our factory can be control from 420 to 450m2/kg and the average specific surface area 402m2/kg. The report models supply and demand for fly ash and granulated blast furnace slag up to 2030. Slag cement proportions of 40 to 50% normally optimize strength. The following video shows the production of BFS slag and emphasizes the important role it plays in the construction of our world：, Phone: 0086-0371-63313738 / 0086-18039114854. Bentonite Uses, Status and Processing in India, Gypsum: A Mineral Resource with a Variety of Uses. These two materials can be widely used in construction, infrastructure and agriculture. When used as earth covering for correcting soft ground, its light weight reduces the danger of lateral soil flow as well as the amount of consolidation settlement. It is easy to process which enables the road can be opened to traffic immediately after the end of the work, and road compaction base can continue to be carried out even on rainy days, which is widely praised. Ground granulated blast furnace slag is an eco-friendly material with regard to its production process and usage. It can be broadly categorized into air-cooled slag and granulated slag. Blast furnace slag is a non-metallic residue usually obtained from steel plants or from the reduction of ores in a blast furnace. If durability parameters are specified (e.g. Also, concrete with coarse slag aggregate is more resistant to high temperatures; that is, this concrete has more residual compressive strength than conventional concrete. The fineness of discharge can be controlled to 2-10mm with a handling capacity of 40 tons per hour. 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. Applications Thus with the higher compressive strengths achievable with slag cement, structural stiffness can be enhanced, and load deflections minimized. By: Ashley December 12, 2019 Last Updated :December 02, 2020. Reducing the "urban heat island" effect by making concrete lighter in color thus reflecting more light and cooling structures and pavements with exposed concrete. When used as part of a portland cement concrete, slag reacts with both the water (latent hydraulic reaction) and the hydrated cement paste (pozzolanic reaction), resulting in a … Ground granulated blast furnace slag is widely used with its characteristics of cost-effective, green effect, hydraulic property as raw material for cement, civil engineering works, fertilizer and so on. Blast furnace slag cement is the mixture of ordinary Portland cement and fine granulated blast furnace slag obtained as a by product in the manufacture of steel with percent under 70% to that of cement. The resulting cement paste is stronger and denser, thus improving the concrete. permeability, sulfate resistance, alkali-silica reaction (ASR) resistance) up to 70 percent slag cement may be required. Slag cement, originally known as granulated blast-furnace slag, begins with the production of iron. Concretes made with slag cement will generally exhibit higher flexural strength for a given level of compressive strength. If the GGBFS is ground by itself, it can be blended mechanically with cement at the cement mill to make ASTM C595, Type IS, Portland blast-furnace slag cement, or it can be added at the concrete plant to make slag concrete. Generally, high replacement rates are required (50 to 80%) to meet low heat of hydration requirements for mass applications. Use of Ground Granulated Blast Furnace Slag: There are two major uses of Ground granulated blast furnace slag, In the production of high quality-improved slag cement, such as Portland Blast furnace cement (PBFC) and high slag blast furnace cement (HSBFC). Use of blast-furnace slag's as • Sand and gravel for the construction of road beds, • Basic filler in asphalt–concrete mixtures for the construction of road and airport coatings, • Unroasted cement (binder) for reinforcing roadways and • Preparing slow-setting concrete. Slag cement is a hydraulic binder that, like portland cement, reacts with water to form cementitious material (calcium-silicate hydrate or CSH). It has been found that using a slag mix for cementing is beneficial economically and technically as well as better for the environment than Portland cement. When pig iron is smelted in a blast furnace, the flux is added to the raw materials from the blast furnace in addition to iron ore and fuel (coke). Slag cement is used in virtually all concrete applications: Slag cement is also used in non-concrete applications such as soil-cement and hazardous waste solidification. Please enter this 5 digit unlock code on the web page. The rapid quenching "freezes" the molten slag in a glassy state, which gives the product its cementitious properties. Until the 1950’s, granulated slag was used in the manufacture of blended portland cements, or as raw feedstock to make cement clinker. Reducing the amount of virgin material extracted to make concrete. Slag cement is most widely used in concrete, either as a separate cementitious component or as part of a blended cement. The blast furnace slag can be crushed and processed into blast furnace slag aggregate by roller crusher and ground granulated blast furnace slag by ball mill. A list of improvements to hardened concrete follows, with a link to individual Slag Cement in Concrete information sheets for further detail: Production of slag cement creates a value-added product from a material—blast furnace slag—that otherwise might be destined for disposal. The molten slag must first be separated from the molten iron. Ground-granulated blast-furnace slag (GGBFS) is a by-product of iron and steel-making obtained by quenching molten iron slag from a blast furnace in water or steam. Often, slag cement concrete that is many years old will manifest greening when the concrete is broken up (in the non-surface interior portions of the concrete). A specification based on concrete strength at 28 days may be able to use less total cementitious material (portland + slag cement) than a similar plain portland mixture is mixture strength is optimized. GBFS Granulated Blast Furnace Slag GBFS can be used like sand as an additional aggregate for building materials. Secondly, transform the partition board to 2mm, so that the slag can be well broken in the first bin and the slag with particle size <2mm enters the second bin for grinding. Blast furnace slag can be used as paving material after mechanically stabilizing. Slag cement concrete may experience some initial "greening" after placement but this temporary color change will disappear with exposure to light and air (see related FAQ on greening and SCIC #10, "Greening"). Slag. It is a recovered industrial by-product of an iron blast furnace. A typical combination is 50% GGBS with 50% Portland cement, but percentages of GGBS [4] anywhere between 20 and 80 % are commonly used. As an oasis for children, the new space features a James River theme incorporating naturalistic elements of light and green space. The rapid quenching ("granulation") "freezes" slag cement in a glassy state and imparts cementitious properties to the product when ground finely. Used to increase the strength of concrete and used to improve workability of fresh concrete and reduce water demand, shrinkage and permeability of the finished product. For information on proportioning and a table of suggested percentages for various applications and end results, see SCIC #2, Concrete Proportioning. The lighter color of slag cement concrete (compared with concrete made with other cementitous materials - see photo) is generally considered to be a positive benefit, as it not only improves the aesthetic look of concrete, but also increases concrete's reflectivity (albedo) which provides greater mitigation of the "urban heat island effect" (see SCIC #22, "Slag Cement and the Environment"). Blast furnace slag aggregate comes in two forms: For more information on slag aggregates, visit the National Slag Association's website. Air cooled blast furnace slag, results when molten slag from a blast furnace slag cools slowly by ambient air (as opposed to rapid quenching), and is processed through a screening and crushing plant for use principally as a construction aggregate. However, in the 1950’s, slag cement became available in other countries as a separate product. Low permeability reduces the ingress of harmful substances (such as chlorides and sulfates) and the availability of water to catalyze harmful chemical reactions within concrete. The pavilion is the largest, most advanced children’s outpatient facility in the region. The composition of slag essentially depends on the raw materials used in the iron production process. For instance, one combination of portland and slag cement, in combination with a highly reactive aggregate may need as much as 70 percent slag cement to mitigate ASR, while a less reactive aggregate, combined with a lower alkali cement and slag cement may only need 25 percent. For more information, see, Slag cement provides higher levels of compressive strength in concrete when compared with ordinary portland cement (OPC) concrete of equal cementitious materials content. A Portland cement mixed with a designated amount of ground granulated blast-furnace slag. Finally, it is easier to achieve a desired color with colored concrete (see SCIC #19, "Slag Cement in Residential Concrete"). Civil engineering works. Because its specific gravity is smaller than that of pig iron, the molten slag rises above the pig iron during heating, making it easy to be separated and recovered. Ground granulated blast-furnace slag, more commonly referred to as slag or slag cement, is a by-product of steel production. When slag cement is mixed with water, however, the initial hydration is much slower than portland cement mixed with water; therefore, portland cement or salts of alkali metals, principally sodium and potassium or lime, are used to increase the reaction rate of slag cement (ACI 233R). GGBFS is divided into three classifications based on its activity index. Today, in the European cement regulations, there are fourteen types of cement containing blast furnace slag [4]. The process involves cooling of the slag through high-pressure water jets, this leads to formation of granular particles. For more information, see, , "Reducing Thermal Stress in Mass Concrete", , "Suggested Specifications for Slag Cement in Concrete.". Recent years have seen the supply and acceptance of slag cement grow dramatically throughout the U.S. Concrete properties can be improved using Fine Blast Furnace Slag (BFS). Permeability of concrete incorporating slag. What Are the Uses of Blast Furnace Slag (BFS). Make this into a paste, apply and leave for a few minutes, wash off thoroughly, and let it take effect. It also, similar to a pozzolan, consumes by-product calcium hydroxide from the hydration of portland cement to form additional CSH. GGBS Concrete GGBS Proportions On its own, ground granulated blast furnace slag (GGBS) hardens very slowly and, for use in concrete, it needs to be activated by combining it with Portland cement. It may provide a small decrease in water demand (see, Slag cement, when used as a separate component in a concrete mixture, is specified through ASTM C 989, Low concrete permeability is essential for long-term durability, especially with regard to corrosion resistance of reinforcing steel. In addition, its hydraulic property makes it hydrate and solidify over time, resulting in high resistance to liquefaction during earthquakes. Under natural conditions, the liquid slag is slowly cooled by the surrounding air. The amount for a specific project depends on several factors including application, early and later age strength requirements, durability requirements and ambient temperature to name a few. It is actually a byproduct of iron production. The molten slag at a temperature of about 1500°C typically use between 25 and 50% slag cement. Granulated blast furnace slag for civil engineering is used for bank protection, soft soil filling, road subgrade, embankment, etc. The residence time of the material in the ball mill can be prolonged, which is conducive to the product fineness reaching the standard. Use of Blast Furnace Slag in Road Construction 23. Just like Portland cement, GGBFS must be finely ground before it can be used in concrete. SLAG Ground granulated blast-furnace slag (Fig. When the iron is processed using a blast furnace, slag and iron both collect at the bottom of the furnace. It is claimed that, concrete incorporating slag perform better in terms of permeability compare with controlled concrete because blast furnace slag in cement paste decreases the size of pores and consequently the permeability of slag concrete is declined. The output of the ball mill is 6.5 t/h, reaching the average hourly output with the comprehensive power consumption per unit 71 kW.h /t. Another effective solution is calcium hypochlorite (usually used for pool shock). Slag Cement Benefits and Use in Concrete. How To Recover Free Gold Wires Using A Shaking Table? Slag is a by-product from steel plants, which is obtained from blast furnaces, during the separation of iron from iron ore. It is used as a mud cake modifier for the cementing of oil and gas wells.. The use of slag cement with a Type I portland cement can provide equivalence to a Type II (moderate sulfate-resistant) or even a Type V (high sulfate-resistant) cement. For more information, see, ASR occurs when the alkalis in portland cement react with certain reactive aggregates to form an expansive gel that causes the concrete to crack, swell and prematurely deteriorate. Modulus of elasticity follows the same relationship as OPC concrete, when based on compressive strength. It reduces the impact on the environment, preserves the precious natural resources needed to sustain the ecosystem, and can reduce the energy consumed in mining, crushed rock and other activities. For more information, see, Mass concrete applications require limitations on the temperature differential between the surface and center of concrete to guard against thermal cracking. Have any question? During the molten cooling and hardening of blast furnace slag, different cooling methods can be adopted to form various types of blast furnace slag products. The molten slag can also be quickly cooled by a column of pressurized water to form a glassy granular slag. Portland Blast-furnace Slag Cement. What’s more, increase the filling rate of the second bin to make its forging surface higher than that of the first bin, so as to slow down the flow rate of materials in the ball mill and greatly increase the specific surface area of slag powder. Address: No.168 Wutong Street, High-Tech Industrial Development Zone of Zhengzhou City, China. This Granulated Slag is the same material used to produce Blastfurnace cement. This is normally a temporary condition and the concrete, upon exposure to air and sunlight, will ultimately become lighter than 100% portland cement concrete. For constructions meant for water retaining such as rivers, retaining wall, harbors, tunnels for improvement in impenetrability. More information can be found in SCA's SCIC #10 and in a "Problem Clinic" discussion in Concrete Producer magazine. The use of ground granulated blast furnace slag (GGBFS) is environmentally sustainable and prevalent in the cement industry, but the original alkali-activated slag binder cannot be used for mine backfilling. If heat curing is used (or ambient curing temperatures relatively high) higher levels within this range are common. The concretes that contain blast furnace slag cement have less permeability, low hydration heat, better operability and processability, higher strength, and higher resistance to hazardous chemicals and Ground granulated blast furnace slag (GGBFS) is designated in ASTM C 989 and consists mainly of silicates and aluminosilicates of calcium. The ingredients are heated to nearly 1500 degrees Centigrade to form two components: iron and molten slag. Today, the main by-product of hot metal production in blast furnaces is granulated blast furnace slag (GBS, see statistics).After grinding to cement fineness (GGBS = ground granulated blast furnace slag) it is used as a main constituent of cement or as a separate concrete addition. Mass applications use between 50 and 80 percent slag cement, with the thickest, most massive placements normally in the 65 to 80 percent range. A crystal structure will form, resulting in hard, lump slag. As a road structure, it has the advantage with its hydraulic property that will not cause strength loss due to seepage under traffic loading. Use of Blast Furnace Slag Aggregate in Concrete K.G. The output of blast furnace slag can not be ignored. Slag cement (also called ground granulated blast furnace slag) is a hydraulic cement produced during the reduction of iron ore to iron in a blast furnace. Because of the fertilizer components CaO, SiO2 and MgO in ground granulated blast furnace slag, it is used as calcium silicate fertilizer in rice cultivation. Ground granulated blast furnace slag has potential hydraulic performance that can be shown under the action of cement clinker, lime, gypsum and other activators, so it is a high-quality cement raw material. Using GGBFS as a coastal protection backfill material can take advantage of its light weight and large shear angle to effectively reduce the earth pressure of the front sheet pile and reduce the sheet pile section. The processed BFS aggregate does not contain organic impurities, clay, shells or similar materials, and has many valuable properties, which is one of the reasons for chemical reactions with alkaline aggregates. In virtually every case where concrete is exposed to air, the greening will disappear and the concrete will be lighter that concrete made with other cementitious materials (see related FAQ on concrete color and article on Canadian Embassy, where greening occured, then disappeared). It is highly regarded as an environmentally friendly material that can protect the environment by limiting the exploitation of natural resources and reducing energy consumption in the exploitation of natural resources. Slag cement generally improves workability, finishability and pumpability of plastic concrete. It is a recovered industrial by-product of an iron blast furnace. The condition is prolonged with extended moist curing, or on formed surfaces, especially when the form is left on for extended periods. It also dramatically lowers the rate of chloride ion diffusion and carbonation, thus significantly enhancing the corrosion protection offered by the concrete to the reinforcing steel.