• Resources Recycling
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• v.6 no.4
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• pp.3-10
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• 1997

Electric are furnace dust (EAF dust) generated in steel production based on scrap melting is contained Zn and Fe about 25 and 30 percent by weight, respectively. From a metallurgical point of view, the dust could be regarded as a raw material for Zn and Fe source. To recover the Zn in the metal from EAF dust, many system are proposed such as Arc Plasma Furmace and Pb splasher method. In this study, to recover high purity Zn from Pb splasing alloy, Zn distillation is carried out at the temperature of 1123, 1173, 1223, 1273 K, the gas flow rate of 2.5, 5.0, 8.0 Ni/min and the distilling time of 10, 30, 60, 90 minutes. The main results obtained from this study are as follows:(1) The amount of evaporated Zn and its evaporating rate increased with increasing temperature, but purity of Zn decreased with increasing temperature. Optimum temperature range was found out to be between 1173∼1223K. (2) The amount of evaporated Zn and evaporation rate increased with increasing gas flow rate at a given temperature and distillation time. Gas flow rate has more influence over the amount of evaporated Zn and evaporation rate with increasing temperature.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.11a
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• pp.32-37
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• 2005

The characteristics of the metal melting and radionuclide distribution of the radioactive has been investigated in a lab-scale arc furnace. The slag former based on the constituents of silica, calcium oxide, aluminum oxide, borate and calcium fluoride additions was used for melting of the stainless and carbon steel. In the melting of the stainless steel, the amount of slag formation increased with an increase of the concentration of the slag former. But the effects of the slag basicity on the amount of stag formation showed a local maximum value of the slag formation with an increase of the basicity index in the melting of the stainless steel as well as in the melting of the carbon steel. With an increase of the amount of slag former addition, the trends of the cobalt distribution into the ingot and the stag depended on the kind of slag former used in the melting of the stainless steel while the effect of the slag basicity on the distribution of the cobalt was not clarified in the melting of carbon steel. Tn the melting of the carbon steel, the strontium was captured at up to $50\%$ into the slag phase. Cesium was completely eliminated from the melt of the stainless steel as well as the carbon steel and distributed to the dust phase.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.3
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• pp.129-135
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• 2011

EAF dust from steel industry used as primary materials for the production of lightweight aggregates. Fe compounds in EAF dust plays an important role in the bloating reaction. This study was conducted to evaluate the feasibility of using bottom ash and dredged soil from coal power plant and EAF dust. The effect of different raw material compositions and sintering temperatures on the lightweight aggregate properties were evaluated. The characteristic of thermal bloating of bottom ash and dredged soil were mainly influenced by ferrous materials. The specific gravity of aggregate was decreased with the addition of EAF dust and kerosene was reduced sintering temperature on the bloating formation. Lightweight aggregate containing 10% EAF dust having apparent density under 1.0 g/$cm^3$ were produced at $1150{\sim}1200^{\circ}C$.

• Resources Recycling
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• v.12 no.6
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• pp.47-56
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• 2003

PVC(polyvinyl chloride) powder were mixed with EAF(Electric Arc Furnace) dust and made as pellets. In order to recover the hydrochloride emitted from pyrolysis of PVC and the valuable metals in dust through making chlorides, pellets were roasted at $300 ^{\circ}C$ and investigated about the generation of chlorides. Two dust samples were collected at I steel making Co. and P Co. (called I dust and P dust respectively), which were mainly composed of zincite and franklinite. It was confirmed that about 50% of Zn in I dust and 48% of Zn in P dust compose zincite. The emission of HCl gas was completed in 15 min at 30$0^{\circ}C$ and the HCl mostly reacted with dust and made chlorides under 20% PVC mixed ratio. Because the reaction of HCl with zincite was faster than with franklinit, when generation and volatilization of ferric chloride is not allowed, the equivalent PVC powder mixed ratio in pellet depended on the amount of zincite in dust.

• Resources Recycling
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• v.9 no.4
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• pp.3-15
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• 2000

Reduction of Electric Arc Furnace dust with carbon (graphite) was studied at the temperature range of $800^{\circ}C$ to $1100^{\circ}C$ in Ar gas atmosphere. The briquetted dust with graphite powder was heated in a vertical tube furnace for given reaction time and Quenched in Ar gas atmosphere. It was found that initially the reduction of Zn was chemically controlled and the activation energy was about 120 KJ/mole. Because the almost all of Pb was removed with Cl in the form of $PbCl_2$, it is considered that Pb is removed by chloride reduction. Cu was vaporized as a chloride up to 30% of its original content, but the remaining of Cu would be accumulated with the reduced iron. and also, Cd was removed completely within 15 min. at $1000^{\circ}C$.

• Resources Recycling
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• v.30 no.1
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• pp.66-76
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• 2021

Electric arc furnace dust (EAFD) contains compounds, such as oxides and chlorides, including large quantities of Zn, Pb and Fe. An efficient and stable method for the extraction of metal elements from EAFD is the Rotary Kiln Process. This method is used to recover Zn in the form of crude ZnO (approximately 60%) via the addition of a reducing agent (coke, anthracite) and limestone (for basicity control) to EAFD. This process is commonly used in industry as well as in research and development. Currently, this method is used in many Korean commercial plants, producing approximately 150,000 tons of Crude ZnO per year. The majority of Zn is found in crude ZnO (approximately 76%). In addition components such as Pb, Cd, Sn, In, Fe, Cl, and F are present as oxides, chlorides, and alkaline compounds. This elements have an adverse effect on the zinc smelting process. Therefore, a refining process that eliminates these impurities is essential. In this study, we developed a process technology that efficiently separates Zn and Pb from byproducts (mainly chlorides). A bag filter was used to collect Zn and Pb generated during the dry purification process of crude ZnO. Pure components were recovered as metals or metal carbonate.

• Journal of the Korean Ceramic Society
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• v.43 no.2 s.285
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• pp.136-141
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• 2006

The stabilizing behavior of heavy metals in the silicate glass containing Electric Arc Furnace dust (EAF dust) were studied by the Toxic Characterization Leaching Procedure (TCLP) test, and the change of crystalline phase and glass network structure were investigated as a function of EAF dust content added. The glass containing EAF dust of $30\;wt\%$ an oxygen/network former ratio(R) of $2\~3$ allowing a fairly stable network structure thus showed much lower heavy metal leaching concentration than that for containing EAF dust above $50\;wt\%$ at TCLP test. For the glass containing EAF dust $50\~60\;wt\%$, however, the R was over 3, which weakened the glass network structure and increased the heavy metals leachate. Adding the EAF dust to a glass decreased the degree of Si-O-Si symmetry and increased the number of non-bridging oxygen, which decreased the chemical durability of glasses. When the dust content in a glass was over $70\;wt\%$, the Zn and Fe ions reacted to form the spinel crystal rather than to bind to network structure of glass and leaching concentration of those ions from the specimen decreased, so the spinel phase could be attributed to lowering a heavy metal leaching.

• Resources Recycling
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• v.7 no.1
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• pp.7-13
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• 1998

The electric arc furnace (EAF) dust used in this experiment showed the formation of an irregular agglomerate of small spherical particles and consisted of 27.5% Fe, 18% Zn, 4.83% Pb and 10.2% CaO, and it also contained 3.26% Cl and 0.15% F. IR spectra peaks of Pb(OH)Cl were observed at 1630 and 1377 ${cm}^{-1}$ regions and the intensity decreased using an acid treatment (1N ${H}_{2}{SO}_{4}$) and thermal treatment at above 600℃, but it was not affected by washing process. Those of ${Zn}_{5}{(OH)}_{8}{Cl}_{2}$ treated by oxidation showed broad absorption peak at 3600∼3200 ${cm}^{-1}$, main peaks at 1136 and 1040 ${cm}^{-1}$ and a splitting peak at 991 and 921 ${cm}^{-1}$ which were believed to be due to ZnO by oxidation at about 700∼. The IR spectra of the dust residues by a washing process show the same peaks at 3449, 1635, 1439, 875, 571 and 455 ${cm}^{-1}$ regions, but the peaks at 2942, 2862, 1136 and 1040 ${cm}^{-1}$ decreased and disappeared using an acid treatment and washing process, which is believed to be due to the dissolution of zinc hydroxyl chloride.

• Resources Recycling
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• v.29 no.1
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• pp.3-16
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• 2020

This work provides an overview of the steel production process, pretreatment and tramp elements of scraps and recycling technology of dust generated from steelmaking process. Steel is the most common metal used by mankind, with the world production of crude steel in 2018 exceeding 1.8 billion tonnes. Recycling of ferrous scraps reduces CO₂ emissions by about 42 % and saves about 60 % of energy, compared to production steel from iron ore. Steel scraps are usually recycled to both an electric arc furnace (EAF), scrap-based steelmaking and the basic oxygen furnace (BOF), in ore-based steelmaking. EAF steelmaking, which uses iron scrap as a main raw material, is changing to an energy-saving type with a device for preheating scrap. Dust generated from the steelmaking process is recycled in various ways in the steel mill to recover iron and zinc.

• Resources Recycling
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• v.23 no.1
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• pp.58-63
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• 2014

Variety of volatile materials is present in crude-Zinc oxide recovered from EAFD(Electric arc furnace steel dust). Commonly, it is purified by oxidizing roasting. In this study, spherical each specimen prepared crude-zinc oxide like 1~3 mm and 10 mm was tested in vertical tube furnace at the temperature range $600^{\circ}C$ to $1200^{\circ}C$ in oxidizing atmosphere. Oxidizing roasting properties of zinc oxide were investigated using XRD, XRF and ICP-OES. At temperature blow $950^{\circ}C$ volatilization rate were remarkably low. As the temperature increases, the concentration of Zn increased and the concentration and XRD peaks of impurities decreased. The result indicated that volatilization rate depended on specimen size and roasting temperature.