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1
Ionescu, Denisa V. "The hydraulic potential of high iron bearing steel slags." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0018/NQ46358.pdf.
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Monaghan, Brian Joseph. "The kinetics of liquid iron dephosphorization using lime based slags." Thesis, University of Strathclyde, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.626859.
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Borode, J. O. "Dephosphorization of molten pig iron at 1400deg.C using soda slags." Thesis, University of Strathclyde, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372115.
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4
VAZ, GUILHERME DEMBERG. "QUANTIFICATION OF METALLIC IRON LOSSES IN ELECTRIC ARC FURNACE SLAGS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2011. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18624@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>A metalurgia é a ciência que estuda os diversos meios para a transformação
dos metais em materiais úteis à sociedade. A metalurgia do ferro representa a
maior fatia da aplicação dos metais. Por ser tão representativa é chamada de
Siderurgia. Dentre as diversas rotas para a transformação do ferro em aço, as
usinas semi-integradas apresentam um forte apelo ecológico, pois utilizam a
sucata, oriunda da reciclagem de ferro, e o ferro gusa como matérias-primas para a
fusão no Forno Elétrico a Arco. Naturalmente, em todo processo industrial há a
geração de resíduos e, neste caso, o principal é a escória, composta de óxidos
formados e adicionados ao longo da fusão. Seus principais constituintes são: CaO,
SiO2, FeO, MnO, MgO, Al2O3 e P2O5. No entanto, ainda há a presença de Ferro
Metálico, um fato indesejável, pois atua negativamente no rendimento metálico e,
consequentemente, aumenta o custo do aço. Toda escória gerada é beneficiada
com o intuito de recuperar a parte metálica. Este material beneficiado retorna para
as usinas como sucata metálica, contendo teores definidos de ferro metálico. O
teor de ferro presente na sucata recuperada é avaliado pelas empresas
processadoras de escória de maneira indireta por um ensaio de densidade
específica. Havia dúvidas se a sucata recuperada da escória do forno apresentava
teores de ferro que justificasse seu emprego como matéria-prima ferrosa. Assim
sendo, foi proposta uma rota de processamento capaz de mensurar o teor de ferro
presente e permitir a comparação com os teores obtidos com o ensaio de
densidade. Os resultados mostram que i) é possível calcular o impacto no
rendimento, ii) que as sucatas recuperadas apresentam valores inferiores ao
esperado, iii) que a equação de densidade superestima o teor de ferro e iv) que
modificações propostas nos coeficientes da equação vigente melhoram seu grau
de assertividade. Estes resultados foram comprovados em 3 plantas siderúrgicas.<br>Metallurgy is the science that studies the various processes for the
transformation of metals into society useful materials. The iron metallurgy
represents the largest body of the metals application, hence it is called Steel
industry. Among the various routes for the transformation of iron into steel, semiintegrated
plants have a strong ecological appeal due to their extensive use of
scrap, derived from the recycling of iron, and pig iron as raw materials for the
Electric Arc Furnace. Of course, industrial processes generate waste. The major
waste of the Electric Arc Furnace is the slag, a mixture of oxides produced during
the process, containing CaO, SiO2, FeO, MnO, MgO, Al2O3 e P2O5. However,
there is also the presence of metallic iron, a fact undesirable, because it acts
negatively on the metallic yield and therefore increases the cost of steel. All slag
generated is processed in order to recover the metallic iron. The slag beneficiation
returns to the mills a material containing defined levels of iron. The content of
recovered iron is assessed by slag processing companies indirectly by a specific
gravity test. There have been doubts whether the recovered scrap iron content
justify its use as raw ferrous materials. Therefore, it is proposed a processing route
capable of measuring the amount of iron present in the recovered scrap. The
measured iron content is also compared with the levels obtained from the test
density. The results show that i) it is possible to calculate the impact on iron yield,
ii) the recovered iron content is lower than expected, iii) the density equation
overestimates the amount of iron and iv) a correction is proposed to improve the
assertiveness of the density equation. Three steel plants confirmed the results from
this research.
5
Bilen, Idil. "Direct Reduced Iron Production from EAF Slags in Fixed Bed Furnace." Thesis, KTH, Materialvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-117981.
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Electric arc furnace (EAF) slags are basic characteristic slags that include approximately 40 % iron oxide compounds. Iron oxide can be recycled and re-used in the process to decrease amount of waste product besides reducing loss of raw materials. According to result of survey performed by The European Association Representing Metallurgical Slag Producers and Processors (EUROSLAG) in 2010, 8.5 million tons of EAF slag is produced in Europe. High percentage of EAF slag is re-used in road construction as aggregate. However it can be re-cycled in the internal use for metallurgical processes as well. In order to re-use EAF slag in the process as a raw material, direct reduction is a new approach. Direct reduction is reduction of iron containing raw materials with gas or solid reductants without melting of charge. In this study, reduction conditions of 39 % Fe2O3 containing EAF slag in tube furnace was examined. As the reducing agent, metallurgical coke was used. EAF slag was milled and pelletized in raw material preparation step. Pellets were charged to fixed bed type tube furnace in a graphite boat at 1050, 1100 and 1150°C respectively with 150 and 200% of stoichiometrically required amount of metallurgical coke. 5, 10, 15, 30, 60, 90 and 120 minutes process durations were performed. Direct reduced pellets were milled to be characterized by using X-Ray Diffraction (XRD) and chemical analysis methods. Results indicate that increased temperature, process duration and stoichiometry have a positive impact on direct reduction of EAF slag in terms of iron metallization. 90 % metallization degree has been achieved as the result of the study with the process conditions of 200 % stoichiometry and 90 minutes process duration at 1150 °C.
6
Kalcioglu, Ali Ferdi 1960. "Distribution of antimony between carbon-saturated iron and blast furnace slags." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277129.
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Understanding the effects of the process parameters on the distribution behaviour of antimony between metal and slag in the iron blast furnace is critical to develop a universal method of controlling temper embrittlement in commercially pure low alloy steels.
7
Mai, Paolo. "Effect of iron redox state on crystallization behaviour of Fayalite slags." Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-286327.
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In the copper smelting processes, the viscosity of the matte and the slag is an important factor for establishing efficiency. Impurities in the concentrates affect the viscosity not only by changing the melt structure but also by promoting precipitation of solid phase which sharply rises it. In this master thesis, a comprehensive methodology was established to study the MgO effects on the properties of a copper smelting slag. Thus, glassy samples were obtained and after confirmation of the composition and the glassy structure with EDS, SEM, and XRD analysis, they were examined through Ramanspectroscopy to study their glassy structure. Moreover, Mössbauer spectroscopy was used to determine the amount of Fe3+ in the samples. Models from the literature were compared to the experimental data. Coherence with the literature was found with the effect of MgO as a network modifier of the oxide melt structure and a promoter of high coordinated structures. Estimations through models were performed to study the iron redox equilibria of the melt and were compared with experimental data, but it was not possible to find the limit of Fe3+ at which precipitation of solid phase initiates.<br>I kopparsmältningsprocesserna är mattans och slaggens viskositet en viktig faktor för att uppnå effektivitet. Föroreningar i koncentraten påverkar viskositeten inte bara genom att ändra smältstrukturen utan också genom att främja utfällning av fast fas som kraftigt höjer den. I denna magisteruppsats fastställdes en omfattande metod för att studera MgO-effekterna på egenskaperna hos en kopparsmältningsslagg. Således erhölls glasiga prover och efter bekräftelse av kompositionen och den glasiga strukturen med EDS-, SEM- och XRD-analys undersöktes de genom Ramanspektroskopi för att studera deras glasstruktur. Dessutom användes Mössbauerspektroskopi för att bestämma mängden Fe3+ i proverna. Modeller från litteraturen jämfördes med experimentella data. Överensstämmelse med litteraturen hittades med effekten av MgO som ett nätverksmodifierare av oxidsmältstrukturen och en promotor för högkoordinerade strukturer. Uppskattningar genom modeller utfördes för att studera smältans järnredoxjämvikter och dessa jämfördes med experimentella data, men det var inte möjligt att hitta gränsen för Fe3+ vid vilken utfällning av fast fas initierades.
8
Okafor, Edwin Eme. "Early iron smelting in Nsukka-Nigeria : information from slags and residues." Thesis, University of Sheffield, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.700957.
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Liu, Xuliang. "The solubility of cobalt in iron silicate slags at 1573 K." Thesis, Liu, Xuliang (1992) The solubility of cobalt in iron silicate slags at 1573 K. PhD thesis, Murdoch University, 1992. https://researchrepository.murdoch.edu.au/id/eprint/52726/.
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The solubility of cobalt in non-ferrous smelting slags has been studied at 1573 K. The study involved both sulfur-free and sulfur-containing systems.
In the sulfur-free systems, the solubility of cobalt in slag was examined by equilibrating iron silicate slag with liquid Co-Au-Fe or solid Co-Fe alloys under an oxygen pressure of either 10^-9 or 10^-10 atmospheres as controlled by mixture of CO/CO2 gas. Three series of experiments were carried out to evaluate the respective effects of cobalt content, iron/silica ratio and oxide additives on the solubility of cobalt in slags. The melts were contained in either silica, alumina, cobalt or magnesium oxide crucibles. The cobalt solubility in slag was interpreted in terms of an activity coefficient of cobalt oxide, calculated from a knowledge of the activity of cobalt in the alloy, the oxygen pressure in the gas phase and the temperature of equilibration. The activity coefficient of ferrous oxide in the slag was calculated in a similar way.
In the systems containing sulfur, a novel experimental method was employed to study the effect of sulfur on the activity coefficient of cobalt oxide in slag at 1573 K. Iron silicate slag was equilibrated with a liquid Co-Au-Fe alloy and a cobalt matte, with the oxygen and sulfur pressures controlled by mixtures of CO/CO2/SO2 gas at 1573 K. The method was novel since the presence of a low sulfur alloy phase, in addition to matte, allowed the metal activities in the system to be defined. In this way, the activities of cobalt oxide and the activity of cobalt sulphide could be calculated when the respective oxygen and sulfur pressures were defined.
Thermodynamic analysis indicated that the solubility of cobalt in slag containing sulfur could be attributed to a solubility of cobalt sulphide in addition to cobalt oxide. The respective activity coefficients of these species were calculated for the slag along with the activity coefficient of cobalt sulphide in the matte. The data were combined to quantify the distribution coefficient of cobalt between slag and matte as a function of mole fraction of cobalt sulphide in matte as well as the sulfur and oxygen partial pressures.
The effect of iron/sulfur ratio in nickel matte on the distribution coefficients of both cobalt and nickel was investigated finally by the equilibration of nickel matte (with minor cobalt), iron silicate slag and a Ni-Co-Fe-Au alloy, system was allowed to find its own equilibrium under argon, but the oxygen pressure was calculated indirectly and correlated with the change in matte composition.
10
Barati, Sedeh Mansoor Coley Kenneth S. "Kinetics of carbon monoxide-carbon dioxide reaction with iron oxide containing slags." *McMaster only, 2005.
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11
Semykina, Anna. "Recovery of iron and manganese values from metallurgical slags by the oxidation route." Doctoral thesis, KTH, Materialens processvetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-24534.
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In the modern practice, a sustainable development strategy in a domain of wasteutilization is shifting its focus from a general completeness of recycling to a morespecific attention to efficiently utilize elements in the wastes. This is well-illustrated bythe steelmaking slag industries. The major waste product from the steelmaking practiceis slag and its main constituents are: CaO, SiO2, Al2O3, MnO, FeO and so on. The mainfield of application for the steelmaking slags is civil engineering, especially for road andwaterway construction. However, a significant amount of the slag remains in the dumps,damaging the environment as well as requiring a land for secure storage. Efficientrecycling of these materials is of increasing interest worldwide as a result of increasingsustainability in processes with respect to increasing raw material costs and wastereduction.In order to find a practical solution, joint efforts are currently made at the RoyalInstitute of Technology, Sweden and National Metallurgical Academy of Ukraine. Theconcept is based on transformation of non-magnetic wüstite (FeO) to magneticmagnetite (Fe3O4) using an oxidizing atmosphere was proposed.In order to verify the feasibility of the proposed way of slag utilization, experiments onthe ternary CaO-FeO-SiO2 and quaternary CaO-FeO-SiO2-MnO slags systems,accompanied by thermodynamic and kinetic modelling, were performed. The crystalprecipitation during synthetic slag oxidation was observed by Confocal Scanning LaserMicroscopy (CSLM). Precipitated phases were found to be magnetite and manganeseferrite in the spinel form.Obtained magnetite and manganese ferrite can be separated from the slag by magneticseparation.The formation of nanosize manganese ferrite from the CaO-FeO-SiO2-MnO slag systemduring oxidation was investigated. Experiments were conducted in a horizontalresistance furnace in an oxidizing atmosphere (air). The final product was analysed by Xraydiffraction (XRD). The particles size of the manganese ferrite was estimated by theScherrer formula and was found to be of the order of 23-25 nm. In order to get anunderstanding of the magnetic properties of the manganese ferrite recovered from slagtreatment, it was necessary to synthesize a reference compound from pure precursors.The MnFe2O4 nanopowder was synthesized by the oxalate route. The size effects on themagnetic properties of manganese ferrite particles were investigated.IIThe potential way of the magnetite particles separation from liquid slags was investigatedby cold model studies. The experimental technique of mobilising non-conducting,nonmagnetic particles in conducting liquid in crossed electric and magnetic fields wasinvestigated in order to find the way of the particle separation from the liquidsteelmaking slags. The effects of the current density, magnetic field, size and shape ofthe particle on the particle velocity under action of the electromagnetic buoyancy force(EBF) in the electrolyte were analyzed.<br>QC 20100916
12
Anyakwo, C. N. "The kinetics of Cr2̲O3̲ reduction from slags by carbon dissolved in molten iron." Thesis, University of Strathclyde, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382250.
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Vetta, Ivana Gabriella. "Slags and Ores: Metalworking in the Greek Early Iron Age Settlement at Zagora, Andros." Thesis, The University of Sydney, 2020. https://hdl.handle.net/2123/22304.
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Archaeological excavation of the Early Iron Age settlement at Zagora, Andros (Greece), from 1967 to 1974, yielded evidence of metalworking in various locations across the site, however no further analysis was carried out on the material. It is nevertheless clear from this data, as well as the results of archaeological surface survey conducted at the site in 2012, that metal production was an extensive industry at the site. Archaeometallurgical analysis has the potential to provide crucial information regarding metalworking at Zagora and can in turn, contribute to the broader understanding of the integration of industrial activity within the settlement. Such data forms a useful comparison with other contemporary sites at which metalworking was conducted, such as those at Oropos and Eretria, allowing for a better regional understanding of the role of metalworking during the Geometric period. Several different methods of analysis of this archaeometallurgical evidence from Zagora help to provide a framework for understanding the operation of metalworking at the site. Firstly, by cataloguing these finds by stratigraphic context, the spatial distribution and quantification of metallurgical slags and metalworking debris can be established. Secondly, through scientific investigation of the samples, using techniques such as Portable X-Ray Fluorescence, Scanning Electron Microscopy and Inductively Coupled Plasma Mass Spectrometry, the gross composition of the assemblage can be understood through the provision of semiquantitative compositional and mineralogical data. Through detailed analysis of this metallurgical waste, we can begin to identify the manufacturing techniques that were available to the ancient metalworkers of Zagora, the ore sources that they utilised, and the spatial layout of metalworking within the settlement. This analysis will be contextualised within the chaîne opératoire, and how Zagora in turn fits into the wider landscape of Early Iron Age metallurgy.
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Okazaki, T. "The removal of copper and tin from molten pig iron and steel using sulphide slags." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37809.
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Wang, Haijuan. "Investigations on the Oxidation of Iron-chromium and Iron-vanadium Molten Alloys." Doctoral thesis, KTH, Materialens processvetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12955.
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With the progress of high alloy steelmaking processes, it is essential to minimize the loss of valuable metals, like chromium and vanadium during the decarburization process, from both economic as well as environmental view points. One unique technique to realize this aim, used in the present work, is the decarburization of high alloy steel grades using oxygen with CO2 in order to reduce the partial pressure of oxygen. In the present work, the investigation on the oxidation of iron-chromium and iron-vanadium molten alloys under CO2-O2 mixtures was carried out and presented in this dissertation. For oxidation study on Fe-Cr molten alloy with CO2-O2 mixtures, on the basis of thermodynamic analysis, energy balance calculation and modeling results, experimental validation in laboratory was carried out, and later on, the oxidation kinetics of Fe-Cr and Fe-Cr-C melts under controlled partial pressure of oxygen was investigated. Thermodynamics calculation and energy balance estimation demonstrated that, it is possible to use CO2 or CO2-O2 mixtures as decarburizers during EAF process and high initial carbon contents in the steel can be adopted at the beginning in order to reduce the cost. A generic model has been developed to describe the overall process kinetics prevailing in metallurgical reactors containing liquid metal and gas bubbles. This model is general and can be extended further to consider any gas liquid reactions in any chemical engineering reactor, and especially the metallurgical ones, like AOD. In the present dissertation, the model is applied in predicting the evolution of Cr and C contents in a Fe-C-Cr melt during injection of different O2-CO2 mixtures. The related simulation results illustrated that CO2 is efficient in Cr retention. In order to verify the modeling results, 1kg induction furnace experiments were carried out in the present laboratory. The results indicated that the predictions of the model are in good agreement with the experimental results. Meanwhile, the experimental results indicated that the Cr-losses can be significantly lowered by replacing the oxygen with CO2 in the injected gas, specifically for Fe-Cr-C melts with carbon levels higher than about 0.8 mass%. Subsequently, the oxidation kinetics of Fe-Cr and Fe-Cr-C melts was investigated under different CO2-O2 mixtures. It is indicated that, the oxidation rate is controlled by the chemical reaction at the initial stage and the reaction rate can be expressed as at the Cr range of 11-21 mass% in the Fe-Cr melt. For oxidation study on Fe-V liquid alloy, the investigation of the oxidation kinetics was carried out under CO2-O2 mixtures, which is followed by the study on thermodynamic properties of vanadium containing slags. During oxidation of Fe-V melt, in the case of alloys with vanadium contents exceeding 10 mass%, there exists an incubation period before the chemical reactions prevail the process. In addition, the ‘incubation time’ increased with the increase of temperature and the vanadium content, whereas it decreased with the increase of oxygen partial pressure in the oxidant gas. High-temperature mass spectrometric method was used to determine the activity of the vanadium oxide in CaO-MgO-Al2O3-SiO2-V2O3 slags, whereas, the oxidation states of vanadium in the CaO-MgO-Al2O3-SiO2-VOxslag system was studied by XANES method. The results indicated that, higher basicities stabilize higher vanadium oxidation state, whereas, higher temperature stabilizes lower vanadium oxidation state. The present work, which was carried out within the ECO-STEELMAKING project funded by MISTRA via Jernkontoret is expected to lead to implementation of some modifications in high alloy steel production based on fundamental concepts towards more environment-friendly steel processing.<br><p>QC20100628</p>
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Fredriksson, Patrik. "Thermodynamic Studies of the Fe-Pt System and “FeO”-Containing Slags for Application Towards Ladle Refining." Doctoral thesis, KTH, Materials Science and Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3630.
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<p>In the present work, the thermodynamic activites of ironoxide, denoted as "FeO" in the slag systems Al<sub>2</sub>O<sub>3</sub>-"FeO", CaO-"FeO", "FeO"-SiO<sub>2</sub>, Al<sub>2</sub>O<sub>3</sub>-"FeO"-SiO<sub>2</sub>, CaO-"FeO"-SiO<sub>2</sub>and "FeO"-MgO-SiO<sub>2</sub>were investigated by employing the gasequilibration technique at steelmaking temperatures. Thestrategy was to expose the molten slag mixtures kept inplatinum crucibles for an oxygen potential, determined by aCO/CO<sub>2</sub>-ratio. A part of the iron reduced from the "FeO"in the slag phase was dissolved into the Pt crucible.</p><p>In order to obtain the activites of "FeO", chemical analysisof the quenched slag samples together with thermodynamicinformation of the binary metallic system Fe-Pt is required.Careful experimental work was carried out by employing asolid-state galvanic cell technique as well as calorimetricmeasurements in the temperature ranges of 1073-1273 K and300-1988 K respectively. The outcome of these experiments wasincorporated along with previous studies into a CALPHAD-type ofthermodynamic assessment performed with the Thermo-Calcsoftware. The proposed equilibrium diagram enabledextrapolation to higher temperatures.</p><p>The experimentally obtained activites of "FeO" in thepresent work, along with earlier investigations were assessedwith the KTH slag model, THERMOSLAG©. New binaryparameters were evolved and incorporated in THERMOSLAG©.The present model calculations are compared with othercommercially available software such as F*A*C*TandThermo-Calc. The validity of the modified model wasinvestigated by measurements carried out in case of Al<sub>2</sub>O<sub>3</sub>-"FeO"-SiO<sub>2</sub>, CaO-"FeO"-SiO<sub>2</sub>and "FeO"-MgO-SiO<sub>2</sub>ternary slags. The potential of the model tocompute the activities in the case of multicomponent slags wasdemonstrated.</p><p>A correlation between the activity of a metallic oxide in aternary slag system and the sulphide capacity of the slag wasinvestigated by using the solubility of sulphur in the binarysystems CaO-SiO<sub>2</sub>and Al<sub>2</sub>O<sub>3</sub>-CaO along with the sulphide capacity of the Al<sub>2</sub>O<sub>3</sub>-CaO-SiO<sub>2</sub>system. The estimated values of the activitieswere found to be in good agreement with the measured values.This correlation also gives the possibility to elucidate theapplicability of Henry's law to the activity of a metallicsulphide and to determine the order in the affinity of a cationto sulphur between two metallic oxides in a slag.</p><p>Model calculations were performed with THERMOSLAG<sup>©</sup>, by using plant data from the ladle refiningprocess at OVAKO Steel, Hofors, Sweden. It was found thatoxygen estimations in the metal from the "FeO" analyses ofslags, obtained by conventional sampling and analysis methodwere less reliable. Reliable estimation of the oxygen levelsutilising the sulphur partition between the slag and the metalwere carried out using THERMOSLAG© software.</p><p><b>Keywords:</b>Thermodynamics, Activity, Galvanic cell,Calorimetry, Gas equilibration technique, Iron-platinum alloys,FeO, Slags, Modelling, Ladle</p>
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Feng, Huan. "Preparation of glass-ceramics largely using steelmaking slags and study on the effect of iron content on properties of glass-ceramics." Scholarly Commons, 2014. https://scholarlycommons.pacific.edu/uop_etds/219.
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Glass-ceramics were prepared using steelmaking industry waste containing high iron content based on powder sintering and crystallization method. Anthracite was used in varying amounts as the reducing agent to recover iron in raw materials. X-ray diffraction analysis (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscope (SEM) coupled with Energy Dispersive X-ray spectrometer (EDX) were used to study the microstructure of glass-ceramics formed. Bending strength and micro-harness of the samples were compared. When 12g of anthracite was used, ionic iron (Fe 2+ /Fe 3+ ) content was reduced to 4.7% and total iron content was reduced to 8.0% in parent glass. The main crystalline phases formed were diopside and augite. Crystalline phases were well-distributed ranging between 0.2 to 0.4 µm after crystallization. A maximum bending strength of 91MPa and a maximum micro-hardness of 3466MPa were achieved. Effect of Al 2 O 3 content on glass-ceramics was studied. Both average bending strength and average micro-hardness of glass-ceramics with 15% Al 2 O 3 content were higher than the glass-ceramics with 6% Al 2 O 3 content. Blast furnace dust was used as both a reducing agent to recover iron and a raw material to prepare glass-ceramics. Compared with glass-ceramics using anthracite as the reducing agent, average bending strength of glass-ceramics formed using BF dust was lower, while average micro-hardness was higher.
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Pousette, Hedda. "Investigation into Melting Characteristics of Hydrogen-Reduced Iron Ore Pellets." Thesis, KTH, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-255856.
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What kinetic and thermodynamic characteristics are established in a melt of hydrogen-reduced iron ore pellets? The pellets contain self-fluxing slag components which upon melting form an initial slag. Refining capabilities of this slag, such as dephosphorization power, are investigated in a lab-scale vertical furnace. Understanding the initial slag and the reactions taking place when hydrogen-reduced iron ore pellets melt is important for future optimization of ingoing raw materials as well as industry scale process design. A sample of either crushed hydrogen-reduced iron ore pellets or a powder mixture representative of iron ore pellets in terms of composition was melted in a lab-scale vertical furnace. The sample was lowered into the argon atmosphere furnace which had a temperature of 1600°. The sample was kept inside a magnesia crucible with a molybdenum loosely-fitted lid. The purpose of the lid was to fix the oxygen partial pressure. The reduction degree of the pellets or corresponding powder mixture as well as the total melting times were varied. XRF and OES analysis were employed to find the composition of the slag and metal phases, respectively. SEM analysis was employed to investigate phases present in the slag. Comparison of melted iron ore pellets and corresponding powder mixture show that powder can be employed to represent reduced iron ore pellets accurately. It was found that reduction degree strongly impacts both phosphorus and vanadium distributions as well as the types of phases formed in the slag fraction. During melting, almost all of the Vanadium and most of the Phosphorus content goes to the slag fraction. At lower reduction degrees, dephosphorization is greater; however, the Phosphorus content in the steel is still quite high at 130 ppm or higher. Modification to the amount and/or composition of the self-fluxing slag is suggested to reach lower levels of phosphorus in the steel.<br>Vilka kinetiska och termodynamiska egenskaper skapas i en smälta av vätgasreducerade järnmalmspellets? Pellets innehåller självflussande slaggkomponenter som vid smältning bildar en initial slagg. Slaggens raffineringsförmåga, till exempel fosforreningsförmåga, undersöks i laboratorieskala. För framtida optimering av ingående råvaror såväl som industriellskalig processdesign är det viktigt att förstå den initiala slaggen samt de reaktioner som äger rum vid nedsmältning av vätgasreducerade järnmalmspellets. Ett prov av antingen krossade vätgasreducerade järnmalmspellets eller en pulverblandning som är representativ för järnmalmspellets med avseende på sammansättning smältes ned i en laboratorieskalig vertikal ugn. Ugnen hade en argonatmosfär och temperatur på 1600°C då provet sänktes ner i ugnen för smältning. En magnesiumoxiddegel med ett löst inpassat molybdenlock användes som behållare för provet under nedsmältningen. Syftet med locket var att kontrollera syrgaspartialtrycket. Reduktionsgraden av pellets eller motsvarande pulverblandning såväl som de totala smältningstiderna varierades. XRF och OES mätverktyg användes för att undersöka sammansättning av slagg- och metallfraktionerna. SEM analys användes för att identifiera närvarande faser i slaggfraktionen. Jämförelse av nedsmälta vätgasreducerade järnmalmspellets med motsvarande pulverblandning visar att de två är representativa av varandra till stor grad. Resultaten visar på att reduktionsgraden påverkar starkt både fosfor- och vanadinfördelningarna samt faserna som bildas i slaggfraktionen. Vid smältning går nästan all mängd vanadin och majoriteten av fosfor till slaggfraktionen. Vid lägre reduktionsgrader är fosforreningen bättre. Fosforhalten i stålet är relativt hög och har ett värde på 130 ppm eller högre för samtliga prover. Ändring av mängden och/eller sammansättning av den självflussande slaggen rekommenderas för att nå lägre nivåer av fosfor i stålet.
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Ekengård, Johan. "Slag/Metal Metallurgy in Iron and Steel Melts." Doctoral thesis, KTH, Tillämpad processmetallurgi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187228.
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In this work, the metal and slag phase mixing in three steps of a ladle refining operation of steel melts and for an oxygen balance during cooling of cast iron melts have been studied at two Swedish steel plants and at two Swedish cast iron foundries, respectively. In order to predict the oxygen activity in the steel bulk in equilibrium with the top slag as well as in metal droplets in the top slag in equilibrium with the top slag, three slag models were used. In addition, the assumptions of a sulphur-oxygen equilibrium between steel and slag and the dilute solution model for the liquid steel phase were utilized in the calculations. Measured oxygen activities in steel bulk, which varied between 3.5-6 ppm, were compared to predicted oxygen activities. The differences between the predicted and measured oxygen activities were found to be significant (0-500%) and the reasons for the differences are discussed in the thesis. Slag samples have been evaluated to determine the distribution of the metal droplets. The results show that the relatively largest numbers of metal droplets are present in the slag samples taken before vacuum degassing. Also, the projected interfacial area between steel bulk and top slag has been compared to the interfacial area between the metal droplets and slag. The results show that the droplet-slag interfacial area is 3 to 14 times larger than the flat projected interfacial area between the steel and top slag. Furthermore, the effect of the reactions between top slag and steel and the slag viscosity on the metal droplet formation is discussed. The results show significant differences between the steel bulk and steel droplet compositions and the reasons for the differences are discussed in the thesis. The oxygen activity in different cast irons was studied. Plant trials were performed at three occasions for lamellar, compacted and nodular iron melts. The results show that at temperatures close to the liquidus temperature the oxygen activities were 0.03-0.1 ppm for LGI, around 0.02 ppm for CGI, and 0.001ppm for SGI. In addition, it was found that as the oxygen activities increased with time after an Mg treatment, the ability to form a compact graphite or a nodular graphite in Mg-treated iron melts was decreased. Also, extrapolated oxygen activity differences up to 0.07 ppm were found for different hypoeutectic iron compositions for lamellar graphite iron at the liquidus temperature. Overall, the observed differences in the dissolved oxygen levels were believed to influence how graphite particles are incorporated into the austenite matrix and how the graphite morphology will be in the cast product.<br><p>QC 20160518</p>
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Svensson, Josefin. "The effect of carbonaceous iron on slag foaming." Thesis, KTH, Materialvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233008.
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The practise of slag foaming has become increasingly important within the scrap-based steelmaking, conducted in the electric arc furnace, due to its many advantages. In addition to increasing the efficiency in the furnace, the foaming protects the furnace equipment from wear and reduces noise pollution. The purpose of this project was to investigate the slag foaming generated through chemical reactions that occur at the addition of carbonaceous iron to the slag, as well as to evaluate the experimental method used. A slag composition of 25 wt% FeO, 40 wt% CaO and 35 wt% SiO2 was chosen. The experiments were conducted using an induction furnace, in a magnesium oxide crucible, placed in a graphite crucible. Iron particles with varying carbon content were added to the magnesium oxide crucible and the subsequent foaming was filmed and observed from above. The method enabled a division of foaming into four stages, which were studied and evaluated separately. The results indicate that the incubation time, referring to the time that passes from the addition of carbonaceous iron particles to the slag until the reactions occur, is dependent of size. A correlation can also be seen between carbon content and foaming time, where increased carbon content results in lengthier foaming.<br>Utövandet av slaggskumning har blivit allt viktigare inom den skrotbaserade ståltillverkningen som utförs i ljusbågsugen, på grund av dess många fördelar. Förutom att öka effektiviteten i ugnen så skyddar den skummande slaggen även ugnsutrustningen mot slitage och reducerar buller. Syftet med detta projekt var att undersöka slaggskumning genererad genom de kemiska reaktioner som inträffar vid tillsats av kolhaltigt järn till slaggen, samt att utvärdera den experimentella metoden som användes. En slaggsammansättning av 25 vikt% FeO, 40 vikt% CaO och 35 vikt% SiO2 valdes. Experiment genomfördes med hjälp av en induktionsugn, i en magnesiumoxiddegel, placerad i en grafitdegel. Järnpartiklar med varierande kolhalt tillsattes i magnesiumoxiddegeln och den efterföljande skumningen filmades och observerades från ovan. Metoden möjliggjorde en uppdelning av skumning i fyra stadier, vilka studerades och utvärderades separat. Resultaten visar på att inkubationstiden, alltså tiden som passerar från att järnpartiklar tillsätts till slaggen, till dess att reaktioner sker, har ett storleksberoende. Ett samband kan även ses mellan kolhalt och skumningstid, där en ökad skumningstid ges av en högre kolhalt.
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Woolley, David E. (David Edward). "Electrochemically enhanced reduction of iron oxide from slag." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/39633.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1998.<br>Vita.<br>Includes bibliographical references (leaves 133-137).<br>An experimental study was performed to measure the rate of reduction of iron oxide from calcia-silica-alumina slag by carbon in iron, and to determine whether the reaction rate can be increased by electrochemical means. It is shown that the reaction rate depends on both the ferric-ferrous cation ratio, and on the total amount of iron in the slag. It was observed that ferric cations are reduced at a faster rate than ferrous cations. This suggests that the overall reaction rate is limited by the rate of the ferric-to-ferrous reduction reaction when the slag contains significant quantities of ferric oxide. Results show that the rate constant decreases at low concentrations of ferrous oxide in the slag. It is concluded that mass transfer in the slag phase controls the overall reaction rate when the slag contains mainly ferrous oxide. Experiments were conducted in an attempt to increase the reaction rate by electrochemical means. The reaction rate was increased by penetrating the slag layer with a metallic rod or plate; this provided an electronic pathway from the metal bath into the bulk slag phase. A small short-circuit current was measured. In order to increase the current, a voltage was applied between the metal bath and an electrode that made electrical contact with the top of the slag layer. The reaction rate increased by 60-100%, and the increase was proportional to the current passed. A current efficiency of nearly 100% was observed for current densities on the order of 500 mA cm-2. The results of this study have been modeled with a new expression for the reaction rate: ... The rate constant k, is the chemical rate constant for the ferric-to-ferrous reduction reaction, and k2 is the mass transfer coefficient for ferrous cations in the slag; numerical values for the constants k, and k2 are offered for certain experimental conditions.<br>by David Edward Woolley.<br>Ph.D.
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Gustavsson, Joel. "Reactions in the Lower Part of the Blast Furnace with Focus on Silicon." Doctoral thesis, Stockholm, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-59.
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Isaksson, Jenny. "Slag Cleaning of a Reduced Iron Silicate Slag by Settling : Influence of Process Parameters and Slag Modification on Copper Content." Licentiate thesis, Luleå tekniska universitet, Mineralteknik och metallurgi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-84798.
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During the pyrometallurgical extraction of copper, a significant part of the copper is lost with discard slag, which decreases profits, overall copper recovery, and efficiency of raw material usage. Smelting furnace slag usually has a copper content that is close to or higher than that of copper ores. The investigation of copper losses to slag is thus a task of practical significance, as the ore grades are depleting. Slag cleaning, e.g., a settling furnace, can reduce copper losses to slag as the mechanically suspended copper-containing droplets separate from slag under the action of gravity and can hence be recovered. An industrial trial was conducted in an electric settling furnace with slag originating from an electric smelting furnace and processed in a zinc fuming furnace. The trial was conducted to increase the understanding of copper losses to slag and how the process parameters temperature and settling time influence the slag copper content. The obtained slag samples were also evaluated to gain better insights as to the settling mechanism and, if any, factors that hinder the copper phases from settling. Slag modification with CaO was also evaluated to investigate how the modification influences the settling of copper phases and, thus, the final slag copper content. Samples collected during the industrial trial were the basis for the evaluation in the current work. The samples came from batches with varying temperatures, settling times, and CaO content collected at four different sample positions. Instrumental techniques, including XRF, FAAS, ICP-SFMS, and SEM-EDS, were used to analyze the chemical compositions of the samples and the appearance of copper and associated phases. The results indicated that the copper content of outgoing slag increased with increasing temperature in the evaluated interval. The copper content was also concluded to be more strongly affected by the temperature compared to the settling time. Regulating the temperature to the lower temperature interval in the settling furnace could thus decrease the final slag copper content. During the slag characterization, it was found that suspended copper-containing phases were hindered from settling, due to the attachment to solid phases and gas bubbles in the slag. By controlling and minimizing the presence of the bottom buildup and thus solid phases in the slag, the copper content can be decreased. The results indicated that the CaO slag modification decreased the final slag copper content, and can thus be used as a modifier for increased settling.
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Bool, Lawrence E. III. "The partitioning of iron during the combustion of pulverized coal." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186374.
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The presence of pyrite in coal has long been known to affect the slagging propensity of the coal when burned in industrial boilers. In particular it has been found that molten pyrite bonds very well to steel furnace tubes. In addition, it has been found that the amount of chemically bound iron greatly influences the slag contact angle and stickiness on steel heat transfer tubes. The goal of this research, which is part of a larger project headed by the PSI Technology Company to study mineral matter transformations during combustion, is to explore and model the mechanisms dominating the fate of iron during combustion. To achieve this goal a well characterized suite of coals was burned in a 17kW downfired laboratory combustor. Fly ash was extracted from the flue gas and size classified. These ash samples were then subjected to a number of analytical techniques including Atomic Absorption Spectroscopy (AA), Energy Dispersive X-Ray (EDX), Computer Controlled Scanning Electron Microscopy (CCSEM), Transmission Electron Microscopy (TEM), and Mossbauer Spectroscopy to determine the ash bulk composition and morphology. Of these techniques, Transmission Electron Microscopy and Mossbauer, were instrumental in determining the iron-silicate interactions during combustion. Utilizing the information gleaned from the fly ash analysis, and work in the literature, it was possible to propose a pathway for iron interactions during combustion. A mechanistic model was then proposed to quantify the competition between processes governing iron oxidation/crystallization and those promoting iron-silicate mixing/reaction. This model described the partitioning of iron between chemically bound and physically bound phases. By utilizing kinetic parameters from the literature and fundamental transport phenomena, this model was able to successfully correlate data from several coals burned under a range of combustion conditions. The model can also be used to quantify the effect of combustion modifications and fuel property changes on iron partitioning.
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Georgakopoulos, Evangelos D. "Iron and steel slag valorization through carbonation and supplementary processes." Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/12323.
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Alkaline industrial wastes are considered potential resources for the mitigation of CO2 emissions by simultaneously capturing and sequestering CO2 through mineralization. Mineralization safely and permanently stores CO2 through its reaction with alkaline earth metals. Apart from natural formations, these elements can also be found in a variety of abundantly available industrial wastes that have high reactivity with CO2, and that are generated close to the emission point-sources. Apparently, it is the applicability and marketability of the carbonated products that define to a great extent the efficiency and viability of the particular process as a point source CO2 mitigation measure. This project investigates the valorization of iron- and steel-making slags through methods incorporating the carbonation of the material, in order to achieve the sequestration of sufficient amounts of CO2 in parallel with the formation of valuable and marketable products. Iron- and steel-manufacturing slags were selected as the most suitable industrial byproducts for the purposes of this research, due to their high production amounts and notable carbonation capacities. The same criteria (production amount and carbonation capacity) were also used for the selection of the iron- and steel-making slag types that are more suitable to the scope of this work. Specifically for the determination of the slag types with the most promising carbonation capacities, the maximum carbonation conversions resulting from recent publications related to the influence of process parameters on the conversion extent of iron- and steel-manufacturing slags, were directly compared to each other using a new index, the Carbonation Weathering Rate, which normalizes the results based on particle size and reaction duration. Among the several iron- and steel-manufacturing slags, basic oxygen furnace (BOF) and blast furnace (BF) slags were found to combine both high production volumes and significant affinity to carbonation. In the context of this research, two different procedures aiming to the formation of value added materials with satisfactory CO2 uptakes were investigated as potential BF and BOF slags valorization methods. In them, carbonation was combined either with granulation and alkali activation (BOF slag), or with hydrothermal conversion (BF slag). Both treatments seemed to be effective and returned encouraging results by managing to store sufficient amounts of CO2 and generating materials with promising qualities. In particular, the performance of the granulation-carbonation of BOF slag as a method leading to the production of secondary aggregates and the sequestration of notable amounts of CO2 in a solid and stable form, was evaluated in this work. For comparison purposes, the material was also subjected to single granulation tests under ambient conditions. In an effort to improve the mechanical properties of the finally synthesized products, apart from water, a mixture of sodium hydroxide and sodium silicate was also tested as a binding agent in both of the employed processes. According to the results, the granules produced after the alkali activation of the material were characterized by remarkably greater particle sizes (from 1 to 5 mm) compared to that of the as received material (0.2 mm), and by enhanced mechanical properties, which in some cases appeared to be adequate for their use as aggregates in construction applications. The maximum CO2 uptake was 40 g CO2/kg of slag and it was achieved after 60 minutes of the combined treatment of alkali activated BOF slag. Regarding the environmental behavior of the synthesized granules, increased levels of Cr and V leaching were noticed from the granules generated by the combination of granulation-carbonation with alkali activation. Nevertheless, the combination of granulation with alkali activation or that of granulation with carbonation were found not to worsen, if not to improve, the leaching behaviour of the granules with regards to the untreated BOF slag. The formation of a zeolitic material with notable heavy metal adsorption capacity, through the hydrothermal conversion of the solid residues resulting from the calcium- extraction stage of the indirect carbonation of BF slag, was also investigated in this project. To this end, calcium was selectively extracted from the slag by leaching, using acetic acid of specific concentration (2 M) as the extraction agent. The residual solids resulting from the filtration of the generated slurry were subsequently subjected to hydrothermal conversion in caustic solution of two different compositions (NaOH of 0.5 M and 2 M). Due to the presence of calcium acetate in the composition of the solid residues, as a result of their inadequate washing, only the hydrothermal conversion attempted using the sodium hydroxide solution of higher concentration (2 M) managed to turn the amorphous slag into a crystalline material, mainly composed by a zeolitic mineral phase (detected by XRD), namely, analcime (NaAlSi2O6·H2O), and tobermorite (Ca5(OH)2Si6O16·4H2O). Finally, the heavy metal adsorption capacity of the particular material was assessed using Ni2+ as the metal for investigation. Three different adsorption models were used for the characterization of the adsorption process, namely Langmuir, Freundlich and Temkin models. Langmuir and Temkin isotherms were found to better describe the process, compared to Freundlich model. Based on the ability of the particular material to adsorb Ni2+ as reported from batch adsorption experiments and ICP-OES analysis, and the maximum monolayer adsorption capacity (Q0 = 11.51 mg/g) as determined by the Langmuir model, the finally synthesized product can potentially be used in wastewater treatment or environmental remediation applications.
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Stetkiewicz, Scott Serreze. "Iron Age iron production in Britain and the near Continent : compositional analyses and smelting systems." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/22982.
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This thesis presents the results of compositional and statistical analyses of Iron Age ironworking residues from sites in Scotland, England, Wales and France. As no framework for ferrous archaeometallurgy previously existed in the main research area of Scotland, a catalog of sites was compiled to determine where targeted scientific analyses could be of most use in creating a regional metallurgical profile. Fieldwork carried out at the site of Meunet Planches in France provided the non- British research component, as extant analyses matching this study’s temporal criteria were not available. A total of 80 new SEM-EDS samples were generated (58 from Scotland and 22 from France), and used together with existing site- and regional-level compositional studies to explore chemical behavior following the procedures laid out by Charlton (2007) and others. These included a range of multivariate statistical techniques such as Hierarchical Clustering Analysis (HCA), Principal Component Analysis (PCA), and Discriminant Analysis (DA). These approaches were considered within the wider discussion of smelting “systems” as defined by Dillmann and L’Heritier (2007), in an effort to visualize the relationship between compositional groups and parent geographic regions. Results indicate overall chemical homogeneity within and between the study regions, suggesting that the systems producing the slag were broadly similar in terms of their operation and reduction “efficiency”. This trend remains stable even when accounting for resource-based influence; implying that appreciable similarities existed between system operations (and therefore potentially human decisions) regardless of the size, age, or complexity of manufacturing industries. Deviation from this main compositional group, exhibited by only a handful of sites, seems to be similarly unrelated to temporal or geographic factors. Rather, it appears to follow the diffusion of slag between the two slag Optima identified by Rehren et al (2007), and on several of the outlier sites relates to the production of hypereutectoid steel.
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Ngekpe, B. E. "Punching shear failure of reinforced concrete flat slabs supported on steel edge column." Thesis, Coventry University, 2016. http://curve.coventry.ac.uk/open/items/5f0f9112-1838-448f-a245-cacc0bc3a9f5/1.
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This study examines punching shear failure at edge supported flat slab. Due to the significant dearth of research on punching shear at edge steel column, this study focuses on the design and performance of a novel shearhead system proposed for edge connection. By considering multi-stage processes and parameters that influence punching shear failure, both numerical and experimental studies were adopted. Firstly linear finite element analysis was employed to study the relationship between the continuous structure and the representative specimen; in order to support decisions on boundary conditions that create the similitude. A nonlinear (NLFEA) model was proposed where various concrete material constitutive models were compared and contrasted. The Total Strain crack model was adopted on the ground that it accounts for the tensile strength of cracked concrete which was ignored in previous theoretical model that lead to poor prediction of punching shear. By considering the appropriate material constitutive model for concrete and steel, material parameters, appropriate modelling scheme capable of predicting punching shear was formulated. The adopted modelling scheme was validated using previous research work. Numerical results reveal that punching shear is influenced most significantly by concrete tensile strength, fracture energy. The shearhead assembly was design with using ACI318-05 and Newzealand codes recommendations with some modifications. These are only codes that provide design guidance on shearhead. Experimental and numerical results show that the shearhead contributes appreciably to punching shear capacity of the edge connection. Various design codes on punching shear were compared; Eurocode 2 provides a good prediction of punching shear at edge support; which correlate well with experimental result. Hence, it was adopted to propose an equation for punching shear for edge connection with shearheads. Most importantly, appropriate design guidance and analytical equation have been proposed for shearhead connection. The design guidance and equation would enable practising Engineers to design shearheads without going through the rigor of experimental or numerical investigation. This study has contributed appreciably to the applicability of steel column in flat slab construction.
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Jonker-Brash, Robina Ann. "Erosion of refractories : mechanisms for dissolution of graphite by iron-carbon melts." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297215.
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Adolfi, Sofia. "Slag inclusion formation during solidification of steel alloys and in cast iron." Licentiate thesis, Stockholm : Materialvetenskap, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4371.
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Zeng, Fengzhencheng. "Phosphorus Retention and Regeneration of EAF Steel Slag and a Synthetic Iron Oxyhydroxide." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1512067344406673.
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Godfrey, Evelyne. "The technology of ancient and medieval directly reduced phosphoric iron." Thesis, University of Bradford, 2007. http://hdl.handle.net/10454/5511.
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After carbon, phosphorus is the most commonly detected element in archaeological iron. The typical phosphoric iron range is 0.1wt% to 1wt%P. The predominant source of phosphorus in iron is the ore smelted. Around 60% of economic UK rock iron ore formations contain over 0.2%P. Under fully reducing conditions, both in liquid-state (cast iron) and solid-state bloomery smelting (direct reduction) processes, such rock ores would be predicted to produce phosphoric iron, and bog iron ores even more so. Ore-metal-slag phosphorus ratios for bloomery iron are derived here, by means of: laboratory experiments; full-scale experimental bloomery smelting; and analysis of remains from three Medieval and two Late Roman-Iron Age iron production sites in England and the Netherlands. Archaeological ore, slag, metal residues (gromps), and iron artefacts were analysed by metallography, SEM-EDS, EPMA, and XRD. The effects of forging and carburising on phosphoric iron were studied by experiment and artefact analysis. The ore to slag %P ratio for solid-state reduction was determined to range from 1:1.2 to 1: 1.8. The ore to metal %P ratio varied from 1:0.2 to 1:0.7-1.4, depending on furnace operating conditions. Archaeological phosphoric iron and steel microstructures resulting from non-equilibrium reduction, heat treatment, and mechanical processing are presented to define the technology of early phosphoric iron. Microstructures were identified by a combination of metallography and chemical analysis. The phosphoric iron artefacts examined appear to be fully functional objects, some cold-worked and carburised. Modern concepts of 'quality' and workability are shown to be inapplicable to the archaeological material.
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Ryösä, Elin. "Mineral Reactions and Slag Formation During Reduction of Olivine Blast Furnace Pellets." Doctoral thesis, Uppsala universitet, Institutionen för geovetenskaper, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9389.
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The present work focuses on mineral reactions and slag formation of LKAB olivine iron ore pellets (MPBO) subjected to reducing conditions in the LKAB experimental blast furnace (EBF). The emphasis is on olivine reactions with surrounding iron oxides. Many factors influence the olivine behaviour. The study was performed by use of micro methods; optical microscopy, micro probe analysis, micro Raman and Mössbuer spectroscopy and thremodynamic modeling. During manufacturing, in oxidising atmosphere at high temperature (1350°C), olivine alterations occur through slag formation and rim reactions with iron oxides and other additives. To be able to describe olivine behaviour in the rather complex blast furnace reduction process one has to consider factors such as reactions kinetics, reduction degree of iron oxides, vertical and horizontal position in the furnace and reactions with alkali. Samples were collected from the EBF both from in shaft probing during operation and from excavation following quenching of the EBF. The initial slag forming olivine consist of primary forsterite – (Mg1.9Fe0.1)SiO4 – with inclusions of hematite and an amorphous silica rich phase, a first corona with lamellae of magnesioferrite, olivine and orthopyroxene, a second corona of amorphous silica and magnesioferrite. During reduction in the upper shaft in the EBF (700-900°C) Fe3+ reduces to Fe2+. The amorphous silica in the second corona absorbs alkali, Al, Fe2+, Mg, and Ca and form glasses of varying compositions. The lamellae in the first corona will merge into a single phase olivine rim. With further reduction the glasses in the second corona will merge with the olivine rim forming an iron rich olivine rim and leaving the elements that do not fit into the olivine crystal lattice as small silicate glass inclusions. Diffusion of magnesium and iron between olivines and iron oxides increase with increasing temperature in the lower shaft of the EBF (750-1100°C). In the cohesive zone of the EBF (1100-1200°C) Fe2+ is not stable any longer and Fe2+ will be expelled from the olivine as metallic iron blebs, and the olivine will form a complex melt with a typical composition of alkali-Al2O3-MgO-SiO2. Alkali plays an important role in this final olivine consumption. The quench time for samples collected with probes and excavation are minutes respectively hours. A study of the quench rate’s effect on the phases showed no differences in the upper shaft. However, in the lower shaft wüstite separates into wüstite and magnetite when wüstite grows out of its stability field during slow cooling of excavated samples. There is also a higher alkali and aluminium deposition in the glass phases surrounding olivines in excavated pellets as a result of alkali and aluminium gas condensing on the burden in the EBF during cooling. Coating applied to olivine pellets was studied in the EBF with the aim to investigate its behaviour, particularly its ability to capture alkali. The coating materials were kaolinite, bauxite, olivine and limestone. No significant reactions were observed in the upper shaft. In the lower shaft a majority of the phases were amorphous and reflecting the original coating compositions. Deposition from the EBF gas phase occurs and kalsilite (KAlSiO4) is found in all samples; coating used for binding alkali is redundant from a quality perspective.
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Rhamdhani, Muhammad Akbar Brooks Geoffrey. "Reaction kinetics and dynamic interfacial phenomena in liquid metal-slag systems." *McMaster only, 2005.
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Pappas, Adlreburg Nickolas. "To Make Iron of Iron : A Comprehensive Analytical Study of Spade Shaped Iron Bars." Thesis, Stockholms universitet, Arkeologiska forskningslaboratoriet, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-145694.
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This thesis aims to provide adequate analytical information on the spade shaped iron bars of Norrland and central Sweden. While their significance has been thoroughly debated for decades, analytical research on them has been confined to cases of single artefacts or theoretical interpretations of their value, meaning and origin. In this study a comprehensive approach is taken into consideration. Based on X-Ray fluorescence (XRF), scanning electron microscopy (SEM) and metallographical analysis this thesis seeks to facilitate new interpretations on quality, production centres and usage based on analytical results. Aiming to settle some of the long lasting questions regarding the artefacts while producing results which can further the discussion by raising new questions, previously unasked.
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Harmanci, Ebru. "Utilization Of Waste Materials From Iron-steel And Zinc Industries For Sorption Of Hydrogen Sulfide At High Concentrations." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605240/index.pdf.
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The slags from iron-steel and zinc industries are rich in metal oxide contents like FeO, MnO, CaO. However, these slags are not used extensively, except some usage in the cement industry. These slags can be used in removing H2S from waste gases from different industrial sources. The purpose of this research is to study the effect of initial concentration of H2S on the capacity and sorbent efficiency of waste materials from iron-steel and zinc industries.
Experiments were conducted in a 25 mm-quartz reactor with simulated gases containing H2S as reactive gas. Breakthrough curves for sulfidation reactions were obtained for 3000 ppmv, 4000 ppmv and 5000 ppmv initial H2S concentrations at the reaction temperature range of 500°<br>C&ndash<br>700°<br>C.
According to the results obtained from the experiments, the H2S removal capacity of both slags increased with increasing reaction temperature, however, the H2S removal capacity of the slags decreases as the initial H2S concentration increases.
Cyclic sulfidation and regeneration tests were applied to both steel and zinc slags in order to determine the regenerability of the slags. In cyclic tests, zinc slag gave better results than steel slag.
A &ldquo<br>Deactivation Model&rdquo<br>was used in order to fit the breakthrough curves obtained experimentally to the breakthrough curves predicted from the deactivation model. A very good fit was obtained for both steel and zinc slags.
Zinc slag was shown to be more suitable for gas cleanup than steel slag taking into account its high H2S removal efficiency, regenerability and low cost (almost free of charge).
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von, Koch Christian, and William Anzén. "Detecting Slag Formation with Deep Learning Methods : An experimental study of different deep learning image segmentation models." Thesis, Linköpings universitet, Datorseende, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177269.
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Image segmentation through neural networks and deep learning have, in the recent decade, become a successful tool for automated decision-making. For Luossavaara-Kiirunavaara Aktiebolag (LKAB), this means identifying the amount of slag inside a furnace through computer vision. There are many prominent convolutional neural network architectures in the literature, and this thesis explores two: a modified U-Net and the PSPNet. The architectures were combined with three loss functions and three class weighting schemes resulting in 18 model configurations that were evaluated and compared. This thesis also explores transfer learning techniques for neural networks tasked with identifying slag in images from inside a furnace. The benefit of transfer learning is that the network can learn to find features from already labeled data of another context. Finally, the thesis explored how temporal information could be utilised by adding an LSTM layer to a model taking pairs of images as input, instead of one. The results show (1) that the PSPNet outperformed the U-Net for all tested configurations in all relevant metrics, (2) that the model is able to find more complex features while converging quicker by using transfer learning, and (3) that utilising temporal information reduced the variance of the predictions, and that the modified PSPNet using an LSTM layer showed promise in handling images with outlying characteristics.
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Sarperi, Laura. "Développement d'une filière de production de bio-GNV à partir de biogaz agricole à l'echelle individuelle." Thesis, Nantes, Ecole des Mines, 2014. http://www.theses.fr/2014EMNA0169/document.
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L’objectif de cette thèse sous contrat cifre entre la société S3d et l’Ecole des Mines de Nantes a été de développer une solution innovante et rentable de production de bio-GNV (Gaz Naturel pour Véhicules) à l’échelle d’une exploitation agricole. Les solutions testées pour capter le CO2 et l’H2S se sont respectivement basées sur les réactions de carbonatation accélérée et la sulfuration du fer sur matériaux alcalins. Pour cela, un co-produits industriels à faible valeur ajoutée a été identifié : les laitiers sidérurgiques issus de four de conversion à oxygène (laitiers BOF pour Basic Oxygen Furnace). Des essais ont été menés à l’échelle du laboratoire sur le CO2 etl’H2S en réacteurs statiques puis en colonne dynamique. L’étude de la carbonatation accélérée du CO2 sur les laitiers BOF et la chaux a permis d’estimer les capacités de capture du CO2 à 49 gCO2/kgBOF pour les BOF contre 265,4 gCO2/kg chaux pour la chaux. La sulfuration des laitiers par H2S a conduit à une capacité de capture de 7,0 ± 1,0 gH2S/kgBOF. Suite à ces résultats, la faisabilité technique a été évaluée sur un biogaz réel produit sur une exploitation agricole vendéenne. Des tests sur site dans une colonne garnie de 200 g de laitiers en lit fixe pendant 46 jours ont permis de valider la faisabilité de la désulfurisation parles laitiers BOF en conditions réelles. Cependant, les réflexions menées sur la carbonatation du CO2 ont conduit à l’introduction d’une solution alternative à savoir la filtration membranaire. Enfin, le bilan économique sur la filière complète a montré que la rentabilité de cette unité était contrainte par un investissement de 75 000 € subventionné à 30% et la consommation d’au moins 6 pleins/semaine<br>Bio-NGV (bio- Natural Gas for Vehicles) is a bio-fuel based on the biogas in which components such as CO2and H2S are removed. But the economical feasibility of available and commercial technologies to perform these removals is limited to 80 Nm3/h of treated biogas. Regarding farm scale biogas plant, fuel needs of 1 fill-upper day would represent the treatment of only 1 Nm3/hof raw biogas. The aim of our work was to develop a solution economically adapted to farm scale to produce bio-NGV from biogas. An alternative and low cost material, BOF slag (Basic Oxygen Furnace slag), was then identified to perform CO2 removal by accelerated carbonation and H2S removal by iron sulfidation. The accelerated carbonation feasibility was evaluated in batch and dynamic reactors under laboratory conditions. But, removal capacities obtained were insufficient to be used under real conditions. Lime was then tested and CO2 removal capacities observed were higher than BOFslag ones but still insufficient. Iron sulfidation by H2Swas also tested under laboratory conditions. Batch reactor and dynamic column investigations led to an interesting H2S removal capacity of 7,0 ± 1,0 gH2S/kgBOF. Based on this result, performances were also validated under real conditions on the biogas produced on site field. According to the whole experimental data, the complete process of bio-NGV production was designed including the H2S removal performed by BOF slag, CO2 removal achieved in two membranes and the 200 bars compression. Finally, the overall economical balance has showed that a total investment of 75 000 € with a subsidy rates of 30% and a weekly fuel consumption between 6 and 28 fill-up/week will lead to a profitable project
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Skogsfjord, Michael, and Minna Blom. "Masugnsslaggens potential som filtermaterial för metaller i vägdagvatten." Thesis, Mälardalen University, Department of Public Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-589.
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<p>Dagvatten från vägar innehåller ofta tungmetaller. De vanligaste metallerna i vägdagvatten är bly, koppar, kadmium, nickel och zink. Dessa föroreningar utgör en belastning i recipienter som tar emot dagvattnet. I denna rapport har bly, koppar och zink reducerats från vägdagvatten genom filtrering i kolonner med amorf, granulerad masugnsslagg och sand. Masugnsslagg, som är en biprodukt från framställningen av järn, är en alkalisk produkt med goda sorptionsegenskaper vilket gör den lämplig att använda som filtermaterial för vatten förorenade med metaller. Sanden användes i studien som referensmaterial. Masugnsslaggen som användes i denna studie är hyttsand från Merox, Oxelösund. Reningshalten för hyttsanden i denna studie uppgick till 79 % för bly, 82 % för koppar samt 92 % för zink. Hyttsandens reducerande förmåga har även undersökts i batchförsök.</p><br><p>Stormwater from roads often contain heavy metals. The most common metals in storm water from roads are lead, copper, cadmium, nickel, and zinc. These pollutants constitute a stress for organisms in recipients that receive the stormwater. In this report lead, copper and zinc have been reduced from road storm water through filtration in columns with granulated iron slag and sand. Iron slag is a by-product from the iron making process, with a high sorption capacity, which makes it suitable as a filter material for water polluted with metals. The sand in this study has been used as reference material. The reducing capacity in the stormwater for the iron slag used in this study, “hyttsand”, was 79 % for lead, 82 % for copper and 92 % for zinc. The reducing capacity of the iron slag was also investigated in batch studies.</p>
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Lindquist, Anna. "Mineraliska material som reaktiva filter för avskiljning av tungmetaller från dagvatten." Thesis, Uppsala University, Department of Earth Sciences, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88875.
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<p>Highly polluted urban storm water from e.g. highways can contain large amounts of heavy metals that may cause harm if they are discharged into recipients. To remove the heavy metals a possible low-cost method that does not require much maintenance, could be the use of reactive filters with filter materials consisting of industrial residues or other cheap mineral based materials. Dissolved metal ions are removed by reactive filters through the processes of ions binding to active sites on the surface of the filter materials, or by formation of insoluble precipitates.</p><p>The ability of CaO-treated granulated blast-furnace slag, iron oxide coated sand, olivine and nepheline to remove seven heavy metals (Cr, Cd, Cu, Ni, Zn, Pb and Hg) from urban storm water was studied. Initially batch experiments were performed where the effect of pH, dissolved organic carbon (DOC) and dissolved ions on the adsorption efficiency was studied. The experiments were conducted with urban storm water and with a reference solution (10 mM NaNO3), both containing the same concentration of heavy metals (approx. 1 μM). The two materials with the best results were further investigated in a column study, where the capacity of the filter was tested. Chemical equilibrium calculations using the program Visual MINTEQ were performed in order to assess the role of precipitation as a mechanism for removal.</p><p>The results show that the blast-furnace slag was the most effective filter material and that it has great potential to be used as a heavy metal remover. Also the iron oxide coated sand worked satisfactory. The highest degree of removal was obtained for lead, cadmium and nickel, for which the removal efficiency exceeded 90% after a load of 300 times the water volume in the columns. For some metals, mainly copper, chromium and mercury the dissolved organic matter affected the removal negatively. The chemical mechanisms causing the removal are specific adsorption to the surfaces of the materials, and for the blast-furnace slag probably precipitation of insoluble metal sulfides.</p><br><p>Starkt förorenat dagvatten som rinner av från exempelvis motorvägar, kan innehålla betydliga mängder tungmetaller som kan orsaka skada om de kommer ut i omgivande vattendrag. En billig metod för tungmetallavskiljning, som inte kräver så mycket underhåll, skulle kunna vara att använda reaktiva filtermaterial bestående av restprodukter eller andra mineraliska lågkostnadsmaterial. Reaktiva filter fungerar som metallavskiljare genom att de lösta metalljonerna binder till ytgrupper på filtermaterialen eller att svårlösliga utfällningar bildas.</p><p>Förmågan att avskilja sju tungmetaller (Cr, Cd, Cu, Ni, Zn, Pb och Hg) ur dagvatten har undersökts för fyra mineraliska filtermaterial, kalciumoxiddopad masugnsslagg, järnoxidsand, olivin och nefelin. Studien inleddes med skakförsök där adsorptionens pH-beroende undersöktes. Försöken gjordes dels med dagvatten, dels med en referenslösning (10 mM NaNO3) med samma tungmetallkoncentration (ca 1μM). Detta gjordes för att studera effekter av löst organiskt material och andra ligander på adsorptionen. Därefter testades de material som uppvisat bäst resultat i skakförsöket i kolonnförsök, ett försök som mer efterliknar en praktisk tillämpning och där filtrets kapacitet kan studeras. Genom kemiska jämviktsberäkningar med programmet Visual MINTEQ var det möjligt att undersöka om bildningen av svårlösliga metallutfällningar bidrog till metallavskiljningen.</p><p>Resultaten visar att slaggen var det effektivaste filtermaterialet och att detta har stor potential att användas för avskiljning av tungmetaller. Även järnoxidsanden fungerade tillfredsställande. De metaller som avskiljdes bäst var bly, kadmium och nickel, för vilka avskiljningen var > 90 % i kolonnförsöket efter en belastning motsvarande 300 gånger vattenmängden i kolonnerna. För vissa metaller, främst koppar, krom och kvicksilver, försämrades avskiljningen betydligt när löst organiskt material fanns närvarande. Mekanismerna som står för avskiljningen är till störst del adsorption till grupper på filtermaterialens ytor, men bildning av svårlösliga metallsulfider är också tänkbar för slaggen.</p>
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Pinto, Samuel Santos de Souza. "Caracterização das propriedades físicas e mecânicas de diferentes tipos de rejeito para aplicação em pavimentos." Universidade Federal de Viçosa, 2013. http://locus.ufv.br/handle/123456789/3831.
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Previous issue date: 2013-03-21<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>This research work was aimed towards the geotechnical characterization of samples from iron ore rejects coming from flotation and magnetic separation processes, together with the addition of LD steel slag, in order to use these materials as components for base of paved roads. In order to reach such goal, this research work was also concentrated in studying techniques for the utilization of such materials considered as rejects of the iron ore industry, considering the use of mixtures from flotation and magnetic separation rejects combined with LD steel slag and local granular soils, in order to reduce environmental effects caused by conventional methods of storage of these rejects in tailing dams and pile rejects, generally disposed at the mine environment.The findings of the experimental program carried out through this research were based on the following geotechnical testes: characterization; compaction and CBR performed at normal, intermediary and modified compaction efforts; triaxial drained tests; resilient modulus tests; and sand equivalent test. Test results from granulometric stabilization techniques as well as those obtained from CBR and expansion tests, showed that the studied iron ore rejects are suitable for being used as subbase layers of flexible pavements, according to the "Design method of flexible pavements" from DNIT. Also, the laboratory testing program consisted of performing repeated load triaxial resilient modulus tests for these rejects and their mixtures. The best constitutive relationship was the one relating the resilient modulus and the bulk stress, M R = K 1θ K 2 . Finally, laboratory test results showed that these rejects and their mixtures are potentially suitable for application in pavement structures.<br>Este trabalho teve como objetivo a investigação em laboratório das características e propriedades geotécnicas (físicas e mecânicas) de rejeitos de minério de ferro (oriundos dos processos de flotação e concentração magnéticas) e escória de aciaria LD, com o propósito de inseri-los como material de construção em pavimentos rodoviários. Para tanto, nesta dissertação buscou-se encontrar técnicas de aproveitamento de materiais considerados como rejeitos dos processos do beneficiamento de minério de ferro, fazendo uso de misturas entre os rejeitos de flotação, de concentração magnética, escória de aciaria e cascalho, de forma a reduzir os impactos ambientais oriundos do seu armazenamento dentro da circunscrição da mina. Os resultados encontrados através do programa experimental realizado para a formulação desta dissertação basearam-se em um programa experimental com a seguintes ensaios geotécnicos: caracterização; compactação e CBR (Califórnia Bearing Ratio), nas energias de Proctor normal, intermediário e modificado; ensaios triaxiais drenados e triaxiais de cargas repetidas (módulo de resiliência); e, por ultimo, equivalente de areia. Os resultados da composição granulométrica assim como os resultados de CBR bem como suas expansões, indicaram que os rejeitos estudados são compatíveis para utilização como materiais de sub- base de pavimentos flexíveis, segundo o "Método de Projetos de Pavimentos Flexíveis" do DNIT. O melhor ajuste dos resultados de módulo de resiliência em termos de R2 foi o modelo que utiliza a primeira invariante de tensões, M R= K1 θ K2. Logo as misturas desses materiais apresentam potencial para serem utilizados em camadas de pavimento.
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Blaha, Marek. "Optimalizace výroby litinových odlitků za účelem snížení výskytu vad." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231936.
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The presented diploma thesis is focused on defects of castings as well as optimization of production with the aim of reducing the number of defective products. The theoretical part is focused on basic information about cast iron and its production, structure and mechanical properties. Another part of this thesis describes the defects of castings and options for non-destructive testing of cast iron castings. In the experimental part are analyzed three sorts of defective casting. Castings for testing were provided by JMA s.r.o. foundry. The summary contains tests results and proposals for optimization of production.
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Mamani-Calcina, Elmer Antonio. "Microanálise de inclusões não-metálicas de artefatos ferrosos: investigação da assinatura química de procedência (Real Fábrica de Ferro São João de Ipanema, Sítio de Afonso Sardinha, Sítio de Missões e Mossend Iron Works) por análise hierárquica de conglomerados." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-18012017-151954/.
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Técnicas de caracterização microestrutural, incluindo microanálise química EDS (energy dispersive spectrometry), foram usadas para investigar as inclusões não-metálicas de amostras ferrosas da Real Fábrica de Ferro São João de Ipanema (Sorocaba, século XIX), da Ponte D. Pedro II (Bahia, produzida na Escócia, Mossend Iron Works, século XIX) e dos sítios arqueológicos de São Miguel das Missões (Rio Grande do Sul, século XVII) e de Afonso Sardinha (Sorocaba, século XVI). Estes resultados foram analisados por métodos estatísticos com o objetivo de estabelecer a assinatura química de cada uma das quatro procedências testadas. A análise dos gráficos bivariantes dos resultados de microanálise de inclusões \"globais\" (% SiO2 versus %Al2O3; %CaO versus %K2O; %MgO versus %Al2O3 e % SiO2 versus %FeO) não permitiu separar os resultados em agrupamentos significativos com relação à procedência das amostras. Os resultados de microanálise da correlação dos teores de %TiO2 e %V2O5 presentes na fase wüstita da microestrutura das inclusões de escória mostraram, no entanto, um agrupamento significativo para os resultados dos artefatos ferrosos de Bahia e de Missões, mas não permitiram separar os resultados dos artefatos de Ipanema e de Sardinha. Deste modo, foi usada a análise hierárquica de conglomerados dos resultados de microanálise das inclusões \"globais\" e de seus microconstituintes (fase wüstita e \"matriz\") com o objetivo de separar os resultados em quatro grupos coincidentes com as quatro procedências investigadas. Somente a análise hierárquica de conglomerados usando os teores de %MgO, %TiO2, %V2O5, %MnO e %Al2O3 presentes na fase wüstita permitiu separar com sucesso os quatro grupos de resultados. Finalmente, a baixa fração volumétrica de inclusões de escória das amostras de Ipanema (~1% contra uma média de 4% das demais amostras) indica a existência de certo grau de domínio tecnológico dos processos produtivos da Real Fábrica de Ferro São João de Ipanema.<br>Microstructural characterization techniques, including EDX (Energy Dispersive X-ray Analysis) microanalyses, were used to investigate the slag inclusions of the microstructure of ferrous artifacts of the Royal Iron Factory of São João de Ipanema (first steel plant of Brazil, XIX century), the D. Pedro II Bridge (located in Bahia, assembled in XIX century and produced in Scotland) and the archaeological sites of São Miguel de Missões (Rio Grande do Sul, Brazil, production site of iron artifacts, the XVIII century) and Afonso Sardinha (São Paulo, Brazil production site of iron artifacts, XVI century). The microanalyses results were analyzed by a hierarchical cluster analysis and the dendrogram with the microanalyses results of the wustite phase (using as critical variables the contents of MnO, MgO, Al2O3, V2O5 and TiO2) allowed the identification of four clusters, which successfully represented the samples of the four production sites (Ipanema, Sardinha, Missões and Bahia). The comparatively low volumetric fraction of slag inclusions in the samples of Ipanema (~1% whit an average of 4% others samples) indicated the existence of some degree of proficiency in the ironmaking processing of the Royal Iron Factory of São João de Ipanema.
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Runtti, H. (Hanna). "Utilisation of industrial by-products in water treatment:carbon-and silicate-based materials as adsorbents for metals and sulphate removal." Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526212630.
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Abstract Pollutant (such as metals and sulphate) contamination exists in the wastewaters of many industries, including mining operations, metal plating facilities, and tanneries. Adsorption is one of the most commonly used processes for the removal of pollutants from waters and wastewaters due to its high efficiency and simple operation. Activated carbon is the most frequently used adsorbent material, although its high cost inhibits its widespread use in wastewater treatment. Therefore, there is a need to develop other adsorbents from alternative inexpensive raw materials such as locally available industrial and mineral waste and by-products. The aim of this thesis was to study the possibility of using industrial waste materials such as carbon residue, metakaolin, blast-furnace slag and analcime as an inexpensive sorbent for iron, copper, nickel, arsenic, antimony and sulphate removal from aqueous solutions. To enhance their adsorption capacity, different chemical treatments (i.e. activation, modification, geopolymerisation) were performed. As a result, the level of removal of iron, copper and nickel by carbon residue and zinc chloride activated carbon residue was higher than that by the commercial activated carbon. Iron chloride modified carbon residue was the most effective sorbent material for sulphate removal when compared to the other studied chemically modified/activated carbon residues. Blast-furnace slag and metakaolin geopolymers as well as their raw materials, were examined for the simultaneous removal of nickel, arsenic and antimony from the spiked mine effluent. In the case of blast-furnace slag, geopolymerisation clearly increased the efficiency of nickel, arsenic and antimony removal to a beneficial level. The barium chloride modified blast-furnace-slag geopolymer was a very efficient sorbent material for sulphate removal and it could thus be a technically feasible sulphate sorbent for wastewater treatment (e.g. in the mining industry in applications in which very low sulphate levels are desired). Barium chloride modified acid washed analcime could also be a potential sorbent for sulphate removal<br>Tiivistelmä Teollisuuden jätevedet kuten kaivosvedet ja metalliteollisuuden prosessien jätevedet voivat sisältää monenlaisia haitallisia ja jopa myrkyllisiä aineita kuten metalleja ja sulfaattia. Adsorptiota käytetään yleisesti esimerkiksi metallien ja orgaanisten yhdisteiden poistossa vesiliuoksista, koska se on tehokas ja yksinkertainen menetelmä. Aktiivihiili on yleisimmin käytetty adsorbenttimateriaali vedenpuhdituksessa, mutta sen hinta joissain tapauksissa rajoittaa sen käyttöä. Tämän vuoksi on tarvetta kehittää vaihtoehtoisia adsorbenttimateriaaleja edullisista raaka-aineista. Viime vuosien aikana on raportoitu mm. teollisuus- ja mineraalijätteistä, joita voidaan hyödyntää vesien ja jätevesien puhdistuksessa. Tämän työn tavoitteena oli hyödyntää teollisuudesta muodostuvia jätemateriaaleja (hiilijäännös, metakaoliini, masuunikuona ja analsiimi) raudan, kuparin, nikkelin, arseenin, antimonin tai sulfaatin poistossa malli- ja jätevesistä. Materiaaleja käsiteltiin erilaisilla kemikaaleilla (aktivointi, modifiointi tai geopolymerointi), jotta niiden adsorptiotehokkuudet paranisivivat poistettavia aineita kohtaan. Tulokset osoittivat, että raudan, kuparin ja nikkelin poisto oli sekä käsittelemättömällä että sinkkikloridilla aktivoidulla hiilijäännöksellä korkeampi kuin kaupallisella aktiivihiilellä. Arseenin, nikkelin ja antimonin poistoa kaivosvedestä tutkittiin masuunikuona- ja metakaoliinigeopolymeereillä, joista masuunikuonageopolymeeri osoittautui tehokkaimmaksi metallien poistajaksi. Bariumkloridilla modifioitu masuunikuonageopolymeeri puolestaan poisti erittäin tehokkaasti sulfaattia kaivoksen jätevedestä. Rautakloridilla modifioitu hiilijäännös ja happopesty bariumkloridilla modifioitu analsiimi osoittatuivat myös lupaavaksi materiaaliksi sulfaatin poistossa
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Dumay, Christophe. "Étude de l'affinage oxydant du silicium métallurgique et des ferrosiliciums." Grenoble INPG, 1995. http://www.theses.fr/1995INPG0117.
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Le silicium metallurgique et les ferrosiliciums elabores par voie pyrometallurgique doivent, pour certaines applications, subir un traitement d'affinage visant a en reduire la teneur en aluminium et en calcium. Un tel traitement peut etre effectue par le biais d'une oxydation des alliages liquides (procede tinject chez pechiney-electrometallurgie par exemple). L'objectif de ce travail est de preciser la description physico-chimique et thermodynamique de cet affinage par la mesure et l'analyse de plusieurs de ses parametres fondamentaux. Nous avons tout d'abord mesure par la methode de la goutte posee la tension interfaciale entre les alliages fer-silicium liquides et differents laitiers constitues des oxydes al#2o#3-cao-mgo-na#2o-sio#2. Nous avons montre que la tension interfaciale decroit avec l'enrichissement en silicium de l'alliage et l'addition d'oxydes basiques (cao, mgo, na#2o) au laitier. Les consequences de ces evolutions sur le procede d'affinage tinject sont analysees qualitativement. Les phenomenes interfaciaux dynamiques qui accompagnent le transfert rapide d'une impurete (al, ca) d'un alliage vers un laitier ont ete caracterises. Une etude extensive de l'equilibre thermodynamique entre alliages et laitiers a ensuite permis l'acquisition d'une connaissance precise des coefficients de partage des elements aluminium et calcium entre les deux phases, dans les conditions de traitement industriel (composition des phases, temperature). A l'aide de la technique des cellules d'effusion couplee a la spectrometrie de masse, nous avons mesure les coefficients d'activite a dilution infinie des elements aluminium et calcium dans les alliages fer-silicium. Nous presentons une analyse critique des resultats de ces mesures et de ceux qui s'obtiennent par l'intermediaire de calculs d'equilibre, a partir de l'etude des coefficients de partage
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Goy, Julie. "La métallurgie du cuivre à l'âge du Fer en péninsule d'Oman : organisations et caractéristiques techniques." Thesis, Paris 1, 2019. http://www.theses.fr/2019PA01H063.
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La péninsule d’Oman est une entité géo-culturelle qui s’organise autour des montagnes d’al-Hajjar, extrêmement riches en minerais de cuivre. Ce dernier a probablement été exploité dès la période Hafit (3000 - 2500 av.n.è.) et le métal produit deviendra une matière d’échange avec la Mésopotamie à la période Umm an-Nar (2500 - 1900 av.n.è.). À l’âge du Fer (1350 - 300 av.n.è.), ces échanges deviennent plus flous, mais la production de cuivre elle, ne diminue pas. Les sites de réduction et de travail du métal de la péninsule d’Oman sont extrêmement massifs et fonctionnent à l’aide d’une gestion et d’une organisation complexes. De plus, ce métal ne connaît pas de concurrence, le fer n’ayant été produit qu’à partir de la fin de l’âge du Fer et le bronze étant relativement peu représenté au sein du corpus métallique. Notre étude a tenté d’identifier les procédés mis en place par les métallurgistes grâce à une méthodologie croisant prospections archéo-métallurgiques et analyses physico-chimiques des vestiges de la production (scories, lingots et objets finis). Ces objets ont été retrouvés dans des contextes d’habitats, de caches ou d’ateliers métallurgiques, il s’agit principalement d’armes, de bracelets, de bols et de figurines de serpent, animal auquel les populations locales semblaient vouer un culte exclusif. Les analyses chimiques attestent une fabrication locale, à partir d’un minerai issu des montagnes d’al-Hajjar. Cependant, il apparaît que la pratique du recyclage d’objets contribue activement à l’approvisionnement des populations en cuivre. Le métal obtenu est chimiquement très mélangé et semble avoir été utilisé dans la fabrication de beaucoup d’objets, sans distinction de type ou d’usage. Malgré l’absence d’un système d’écriture connu, les populations de l’âge du Fer livrent des vestiges archéologiques qui attestent d’une organisation sociale complexe, au sein de laquelle le cuivre semble avoir joué un rôle important, en contribuant au maintien d’une identité locale forte<br>The Oman Peninsula is a geo-cultural entity organized around the al-Hajjar mountains, which are extremely rich in copper ores. This metal was probably exploited since the Hafit period (3000 - 2500 BC) and the metal produced will become a trading material with Mesopotamia during the Umm an-Nar period (2500 - 1900 BC). During the Iron Age (1350 - 300 B.C.), these exchanges became more blurred, but copper production did not decrease. The reduction and metalworking sites of the Oman Peninsula are extremely massive and operate with complex management and organization. Moreover, this metal is not competitive, as iron was only produced at the end of the Iron Age and bronze is relatively under-represented in the metallic corpus. Our study attempted to identify the processes implemented by metallurgists using a methodology that combines archaeometallurgical prospecting and physico-chemical analysis of production remains (slag, ingots and finished objects). These objects were found in various contexts : settlements, hiding places or metallurgical workshops. They are mainly weapons, bracelets, bowls and snake figurines, an animal to which the local populations seemed to devote an exclusive cult. Chemical analysis attest a local production, using ore from the al-Hajjar mountains. However, it appears that the practice of recycling objects actively contributes to the supply of copper to the population. The resulting metal is chemically highly mixed and appears to have been used in the manufacture of many objects, regardless of type or use. Despite the absence of a writing system, archaeological remains of the Iron Age populations attest to a complex social organization, in which copper seems to have played an important role, contributing to the development of a strong local identity
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Ponsot, Inès. "Glasses and Glass-Ceramic Components from Inorganic Waste and Novel Processing." Doctoral thesis, Università degli studi di Padova, 2015. http://hdl.handle.net/11577/3424636.
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Thanks to European environmental rules and regulations establishment, waste recycling has become a more and more relevant problematic. For manufacturing plants, especially those producing hazardous wastes, expenses linked to waste production have drastically increased over the last decades. In the proposed work, various hazardous and non-hazardous wastes, among: soda-lime and borosilicate glass cullet, cathode ray tubes glass, exhausted lime from fume abatement systems residues, sludge and slags from ferrous and non-ferrous metallurgy, and pre-stabilized municipal solid waste incinerators ashes are used to elaborate several compositions of glass-ceramics. High-temperature treatment (minimum 800 °C) associated to a Direct Sintering process (30 min) was an efficient way to stabilize chemically the final products. The impact of each waste on the final product’s mechanical properties was studied, but also their synergies between each other, when mixed together. Statistic mixture designs enabled to develop interesting products for modern building applications, such as porous tiles and lightweight panels destined to insulation, with a purpose of fulfilling multifunctional properties.<br>Grazie alle regole e normative ambientali europee istituite, il riciclaggio dei rifiuti è diventato una problematica sempre più rilevante. Per gli impianti di produzione, in particolare quelli che producono rifiuti pericolosi, le spese connesse allo smaltimento sono drasticamente aumentate negli ultimi decenni. Nel lavoro proposto, vari rifiuti, pericolosi o no, vengono utilizzati per elaborare diverse composizioni di vetroceramiche. Si distinguono rottami di vetro della produzione di finestre, di contenitori farmaceutici e di tubi catodici. I rifiuti non vetrosi invece sono calce esausta da residui di sistemi di filtrazione di fumi, scorie metallurgiche da leghe ferrose e non e ceneri da inceneritori. E' presentata nel presente lavoro la ricerca di un metodo di trattamento ad alta temperatura (minima 800 ° C) efficace per stabilizzare chimicamente il prodotto finale, tramite i diversi processi di sinterizzazione diretta, sinter-cristallizzazione e vetrificazione. Sono stati studiati gli effetti di ogni rifiuto sulle proprietà meccaniche del prodotto finale, ma anche le nuove funzionalità ottenute attraverso le sinergie risultanti dalla loro miscela. Miscele calibrate hanno permesso di sviluppare prodotti interessanti per applicazioni edilizie moderne, come le piastrelle porose e pannelli leggeri destinati all’isolamento.
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Eberhardt, Mitchel A. "Trace element leaching from gray iron foundry slags." 2008. http://catalog.hathitrust.org/api/volumes/oclc/233578762.html.
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Elliot, Barry John. "The effect of slag composition on copper losses to silica-saturated iron silicate slags." Thesis, 2015. http://hdl.handle.net/10539/17230.
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Logeshwari, J. "Characterization of Different Slags for Bulk Geotechnical Applications." Thesis, 2017. http://etd.iisc.ac.in/handle/2005/3627.
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Generation of wastes in the form of liquid, solid or gas is inevitable in any industry.Industrial Solid Waste is the waste that is generated from an industrial or manufacturing process and includes the waste generated from non-manufacturing activities as well.Most of these wastes fall under the category of Ashes, Slagsor Sludges. For the present work, three types of secondary lead slag, two types of granulated blast furnace slag (GBS) or iron slag and four types of steel slags were procured and studied.An elaborate study on various characteristics of the slags has been performed. Based on the results, all the possible applications for the individual slags are considered. The performance of the secondary lead slag as an embankment material was analyzed. The slope stability for various conditionswas analyzed using Geo5 and experimentally determined strength parameters. It was found that the material can be used safely for embankment constructions.The CBR values were very good in the range for both GBS and steel slag,thus repeated load triaxial test are done to determine the resilient modulus. k1-k3model was adopted and the regression coefficients were determined. Based on the results the pavement design is done using KENPAVE software. An exercise has been performed to determine the quantity of the conventional material that could be saved, considering the type and size of the pavement. For the aggregate sized steel slag, the tests were done to find the suitability of the material for various applications like, as railway ballast, concrete aggregate, gabion and rip rap stones. And the tests result shows the material to be suitable for these applications and is expected to perform well. Study on morphological parameters reveals that the size and gradation of any material plays an important role in its mechanical behavior, however in the case of slags, this could be tailor made by using appropriate crushers, as per the requirements.
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Logeshwari, J. "Characterization of Different Slags for Bulk Geotechnical Applications." Thesis, 2017. http://etd.iisc.ernet.in/2005/3627.
Full textAbstract:
Generation of wastes in the form of liquid, solid or gas is inevitable in any industry.Industrial Solid Waste is the waste that is generated from an industrial or manufacturing process and includes the waste generated from non-manufacturing activities as well.Most of these wastes fall under the category of Ashes, Slagsor Sludges. For the present work, three types of secondary lead slag, two types of granulated blast furnace slag (GBS) or iron slag and four types of steel slags were procured and studied.An elaborate study on various characteristics of the slags has been performed. Based on the results, all the possible applications for the individual slags are considered. The performance of the secondary lead slag as an embankment material was analyzed. The slope stability for various conditionswas analyzed using Geo5 and experimentally determined strength parameters. It was found that the material can be used safely for embankment constructions.The CBR values were very good in the range for both GBS and steel slag,thus repeated load triaxial test are done to determine the resilient modulus. k1-k3model was adopted and the regression coefficients were determined. Based on the results the pavement design is done using KENPAVE software. An exercise has been performed to determine the quantity of the conventional material that could be saved, considering the type and size of the pavement. For the aggregate sized steel slag, the tests were done to find the suitability of the material for various applications like, as railway ballast, concrete aggregate, gabion and rip rap stones. And the tests result shows the material to be suitable for these applications and is expected to perform well. Study on morphological parameters reveals that the size and gradation of any material plays an important role in its mechanical behavior, however in the case of slags, this could be tailor made by using appropriate crushers, as per the requirements.