Hydrometallurgical extraction of zinc from jordanian. Equipment for pelletizing the dust was evaluated, and a 3footdiameter disc pelletizer with an 8. Pdf the large amount of dust generated in electric arc furnace aligned with its chemical composition makes this dust a potential source of iron in the. Moveable panels or screens are sometimes used to reduce the open area between the furnace and hood and to improve emissionscapture efficiency. The advantage of the induction furnace is a clean, energyefficient and wellcontrollable melting process. A basic characteristic of the eaf is precisely the presence of an electricarc, which exhibits a very high temperature and is placed in an environment exposed to gases vaporization and oxidation of a small metal fraction and the. Approximately 45% of the 1,414 million tons of steel that is produced annually worldwide 3 is generated via the electric arc furnace method 4. Before the start of each heat and scrap charge to the furnace, it can continuously preheat the scrap steel, pig iron and other metal materials by. Currently, usbased minimills using the electric arc furnace eaf method to melt scrap steel generate more than a million tons of steel mill dust annually.
Hydrometallurgical extraction of zinc from jordanian electric arc furnace dust article in hydrometallurgy 1041. Fe2o3, zno, and mno in the eafd can be reduced to fe. Eaf dust is a byproduct of the steel production process, and refers to the dust collected during the melting of steel in an electric arc furnace. Dust accumulation from thi s product may present an explosion hazard in the presence of an ignition source. Classified as a hazardous substance, most of this steel dust can be recycled to obtain zinc oxides used as a raw material for the worlds zinc smelters. Electric arc furnaces eaf generate much dust during operation, which contains very high percentages of zinc, lead, and ir on, as well as toxic organic substances.
When i am working in pearson, i worked on this project 2. Electric arc furnace an overview sciencedirect topics. Ultrahigh power electric arc furnace,melting furnacexi. The electric arc furnace eaf, designed for steelmaking from recycled scrap iron figure 1. Clean air act standards and guidelines for the metals.
An experimental study on the reduction behavior of dust. However, operations such as blowing, sweeping, or moving the dust may result in the following effects if exposure exceeds the exposure limits. Stabilization of electricarc furnace dust in concrete scielo. The electric arc furnaces bring about some special environmental concerns, namely. Electric arc furnace baghouse dust eafd, a waste byproduct of the steelmaking process, contains the elements that are volatilized from the charge during the melting cr, pb, zn, cu and cd. No special requirements regarding chemical composition of eafd. In 2006 alone, it was estimated that global production of eaf dust reached a near 7 million tons, a staggering amount, considering the steel industry continues to expand in tandem with growing economies.
Zinc is of considerable economic value, followed by lead, iron and potentially copper and nickel. The chemical composition of eaf dust samples was investigated by means of a several different analytical methods. It has been reported that approximately 15 to 20 kg of eafd is generated per ton of steel produced 1, 2. Arc furnaces differ from induction furnaces, in that the charged material is directly exposed to an electric arc and the current in the furnace terminals passes through the charged material. Thus, eaf dust has a great potential to be used as a source of metals extraction due to its rich chemical composition and also for the viability of the proposed selective separation process. Dust from electric arc furnaces includes approximately 3040% of zinc and 20% of iron. Sintering dust blast furnace dust electric arc furnace dust characterization. The aim of this study was to investigate the properties. Electric arc furnace dust eafd is a highdensity byproduct of steel production. Technologies to recover and recycle values from, stabilize and dispose of, and glassify and sell electric arc furnace dust by pyrometallurgical, hydrometallurgical, and hybrid methods continue to emerge, be reduced to commercial practice, then succeed and move forward or fail and fade away. Open furnaces have a fume collection hood at least 1 m 3. Electric arc furnace dust under normal conditions does not present an inhalation, ingestion or contact health hazard.
Pdf reduction of electric arc furnace dust pellets by mixture. The eaf dust chemical and phase composition research. The dust contains approximately seven percent of the worlds zinc production 21. In the electric arc furnace, steel is produced only through scrap fusion. It is used to smelt rutile ore into titanium, craft steel, silicon ingots and several alloys using redstone flux. Electric arc furnace dust ko61 material safety data sheet. Electric arc furnace eaf dust is a waste generated in the eaf during the steel production process. The 2sdr process innovative treatment of electric arc furnace dust. In order to make a complete characterization of electric arc furnace eaf dust, as hazardous industrial waste, and to solve its permanent disposal andor recovery, bearing in mind both the volumes formed in the croatian steel industry and experiences of developed industrial countries, a study of its properties was undertaken. Arc furnaces differ from induction furnaces, in that the charged material is directly exposed to an electric arc and the current in the furnace terminals passes through the. Electricarc furnace dust eafd is a byproduct of steel production and recycling.
Heavy metals dust from electric arc furnace ipcbee. Characterisation of electric arc furnace dust generated. Disposalrecycling of electric arc furnace dust, slag, and refractories. Dust formation is strongly linked to the process which can be divided into five steps. Characterization of sintering dust, blast furnace dust and carbon. According to the eafds chemical composition, it is possible to use it as a raw material in decorative ceramic glazes which contain zinc and iron oxides. Equipment for pelletizing the dust was evaluated, and a 3footdiameter disc pelletizer with an 8inchdiameter pin mixer was selected for the pilot trials. Electric arc furnace dust eafd is one of byproducts of steelmaking industry dukelow et al. Characterization of steel mill electricarc furnace dust. Plasma furnace treatment of electric arc furnace dust as. The dusts are commonly processed using the waelz process see e. Recycling of dust from electric arc furnacesa case study. The electric arc furnace eaf dust contains valuable, but dangerous substances, for example, metals and their oxides.
Electric arc furnace dust an overview sciencedirect topics. A basic characteristic of the eaf is precisely the presence of an electricarc, which exhibits a very high temperature and is placed in an environment. Currently, more than half of the electric arc furnace eaf dust produced worldwide is still sent to a land. Recycling of electric arc furnace dust through dissolution in deep eutectic ionic liquids and electrowinning ashraf bakkar impact factor 4. Mixture section 3 toxicology and health information effects of overexposure. Introduction the electric arc furnace eaf, designed for steelmaking from recycled scrap iron see figure 1, also coproduces between 15 to 25 kg of dust per ton of steel. Among different wastes, eaf dust represents one of the most hazardous, since it contains heavy metals such as zn, fe, cr, cd and pb. Used worldwide, these furnaces are featured in minimills that recycle iron scrap for reuse. The xrd and mossbauer spectroscopy analysis of the dust did not make possible obtaining data for some phase, in particular many chemical compounds. Electric arc furnaces use highvoltage electric arcs that are bounced between three graphite electrodes to produce massive amounts of heat.
Plasma furnace treatment of electric arc furnace dust as demonstrated by bethleh donald r. It is difficult to landfill it for environmental reasons, and not desirable in terms of wasting metal. Plasma furnace treatment of electric arc furnace dust as demonstrated by bethleh. Recycling of electric arc furnace eaf dust for use in. Electric arc furnace dust eaf is a hazardous waste generated during steelmaking process in electric arc furnace. The dust collected in bag filters at the end of the eaf fume extraction system is teh final. Understanding environmental leachability of electric arc. The current status of electric arc furnace dust recycling. However, operations such as blowing, sweeping, or moving the dust may result in the following effects. Main metal elemental compositions of electric arc furnace dust eafd and automobile shredder residue asr. The electric arc furnace eaf, designed for steelmaking from recycled scrap iron figure 1, also coproduces between 15 to 25 kg of dust per ton of steel. This slag presents good mechanical properties, and for the most siliceous slag, a high stability which would enable its use by total or partial substitution of certain granulates in civil engineering.
Coatings and oil residue on the product may enhance flammability. Its main components are fe and zn oxides which are important for many applications. A sustainable methodology for recycling electric arc. Technology study electric arc furnace fume systems and control technologies by anonymous and a great selection of related books, art and collectibles available now at. An electric arc furnace eaf is a furnace that heats charged material by means of an electric. Box 328 synonyms tampa, fl 3363328 baghouse dust, k061.
Wastes 2015 solutions, treatments and opportunities, pp. The composition of electric arc furnace dust eafd in wt%. The electric arc furnace is a multiblock machine added by advanced rocketry. Clean air act standards and guidelines for the metals production industry the following are the stationary sources of air pollution for metal production industries, and their corresponding air. Electric arc furnace dust from steel production is generated in considerable amounts worldwide and needs to be treated as hazardous waste. Electric arc furnace dust with a high content of carbon, silicon and sulfur is discussed through the prism of its multicomponent composition, which depends on the specifics of steel production. The eaf dust chemical and phase composition research techniques. Pyrometallurgy, dc arc furnace, electric arc, smelting abstract dc arc furnaces were first used industrially for the reductive smelting of chromite fines to produce ferrochromium thirty years ago. Method and mechanisms of soil stabilization using electric. In the recycling industry, the recuperation of zinc from electric arc furnace dust by the waelz process generates important quantities of slag. Electric arc furnace dust ko61, baghouse dust chemical family. Induction furnace capacities range from less than one kilogram to one hundred tonnes, and are used to melt iron and steel, copper, aluminium, and precious metals.
Some researchers have shown that characterize adequately eaf dust is necessary to use various techniques in combination to determine the phases present, and in particular znfe 2 o 4 and zno 4. Electric arc furnace eaf dust the eaf dust is generated during melting of scrap in electric arc furnace and collected by bag filters or electrostatic precipitators. Power must be inserted by the structures power input plug, input items by the input hatch and output items can be picked up from the output hatch. Dc arc furnaces past, present, and future rodney t. Submerged electric arc furnaces are of two basic types, open and closed. Technologies to recover and recycle values from, stabilize and dispose of, and glassify and sell electric arc furnace dust by pyrometallurgical. Industrial electric arc furnace temperatures can reach 1,800 c 3,272 f, while laboratory units can exceed 3,000 c 5,432 f. Lead and zinc selective precipitation from leach electric. During eaf operation, electricarc furnace dust, eafd, is generated as a result of the vaporization of molten iron with nonferrous metals, co bursting bubbles and the ejection and dragging of particles from the metal bath, slag and other materials in the oven. The whole melting process of consteel electric furnace steelmaking can realize continuous feeding. The current status of electric arc furnace dust recycling in north america.
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