Endre søk
Begrens søket
1 - 18 of 18
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1. Andersson, Charlotte
    et al.
    Björkman, Bo
    Engström, Fredrik
    Mostaghel, Sina
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    The need for fundamental measurements for a sustainable extraction of metals2010Konferansepaper (Fagfellevurdert)
  • 2.
    Andersson, Charlotte
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Björkman, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Engström, Fredrik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Mostaghel, Sina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    The need for fundamental measurements for a sustainable extraction of metals2011Inngår i: Transactions of the Institution of Mining and Metallurgy Section C - Mineral Processing and Extractive Metallurgy, ISSN 0371-9553, E-ISSN 1743-2855, Vol. 120, nr 2, s. 199-204Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The increased need for efficient material processing and efficient utilisation of more complex raw materials and the need for recycling or reusing byproduct and waste streams, are all increased challenges in material processing. To cope with these challenges, there is a need for new basic physical and thermodynamic data. The present paper gives four examples, as well as preliminary data, of areas where increased knowledge of fundamental parameters will increase the possibility for a sustainable extraction of metals. The examples include measurement of solubility of pure individual slag minerals, determination of distribution of leachable elements between different mineralogical phases in slag, influence of alumina on liquidus temperature of a copper slag and thermal diffusivity measurements in magnetite based iron ore pellets, all important in different ways to increase the sustainability of the respective materials involved

  • 3.
    Awe, Samuel Ayowole
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Lennartsson, Andreas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Mostaghel, Sina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Sandström, Åke
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Wise process routes for varying feedstock in base metal extraction2011Inngår i: Proceedings, European Metallurgical Conference EMC 2011: Process Metallurgy, Recycling/Waste Treatment and Prevention, Germany: GDMB , 2011, Vol. 4, s. 1315-1322Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In Sweden, there are several large but low-grade ore deposits that have not been extracted so far. The main reason is presence of impurities such as arsenic and antimony that increase the overall cost of the process and make the extraction uneconomical. In-depth experimental studies, plant data and theoretical modelling and innovations are needed to develop new techniques for an efficient use of the resources. Besides, recycling of metals from end of life scrap and metal containing waste, e.g. waste electric and electronic equipment (WEEE), is an important part of a metal production plant. Most of these secondary raw materials contain mixtures of different metals together with various plastics and ceramics that may adversely affect products and by-products of the metallurgical opera-tion. Therefore, a thorough study on how to control possible changes of properties is required. The aim of the research is to develop an optimum combination of hydro- and pyro- metallurgical path-ways to bleed out impurities from the metal extraction chain and/or convert them into valuable by-products. The first part of the current paper focuses on impurity removal from a complex copper concentrate as an upgrading stage. It is shown that by selective dissolution of tetrahedrite in alkaline sulphide solution, antimony and arsenic would be eliminated and the concentrate can be treated in pyro-metallurgical processes. In the second part of the paper, influences of one of the most common and significant compounds that is included in most of the secondary raw materials, alumina Al2O3, on properties of a copper production slag are explained. Results show that increased alumina content of the slag will cause formation of a new phase and rises the liquidus temperature, while its leaching properties are not adversely affected.

  • 4. Mostaghel, Sina
    Activity: European Slag Conference; Euroslag 20102010Konferansepaper (Annet (populærvitenskap, debatt, mm))
  • 5.
    Mostaghel, Sina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Influence of alumina on the zinc slag fuming processes: an experimental study on physical properties and leaching behaviour of the generated fayalite-type slag2012Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Recycling of secondary raw materials by non-ferrous metal producers is steadily increasing. These materials inevitably introduce various impurities to the production furnaces, which can change the chemical composition, and thereafter, the physical and chemical properties of the products and by-products of the operation. Alumina is one of the most common and significant impurities that enter the furnaces in different ways, including recycling of waste electrical and electronic equipment (WEEE). In order to control and optimize the outcome of the process, a deep understanding of influences of alumina on slag properties is an essence. In the current work, a combination of different experimental techniques and thermodynamic calculations was carried out to investigate the effects of alumina on some of the most important properties of an industrial iron-silicate or fayalite-type slag, from a Swedish base and precious metals producer. For this purpose, a reference slag sample, devoid of alumina addition, and three different mixtures of slag with 5, 10, and 15 wt-% alumina additions were prepared and used for evaluation of density, surface tension, thermal diffusivity, viscosity, melting behaviour, mineralogy and leaching characteristics. Results show that in this type of slag, aluminium can be tetrahedrally coordinated and behave as a network former cation. As a result, increasing the alumina concentration leads to polymerization of the melt, and consequently, an increase in viscosity and thermal diffusivity. It is observed that alumina addition to the slag leads to formation of units with relatively higher molar volumes, which reduces the measured density of the material. Slag samples with higher alumina contents exhibit higher surface tensions, primarily due to the relative lower concentration of the surface-active components. By 5 wt-% alumina addition to the system, the liquidus temperature decreases slightly. Further increase in alumina content (10 and 15 wt-% alumina additions) causes a change in primary crystallization phase field of the material from fayalite (Fe2SiO4) to hercynite (FeAl2O4). This change is associated with a rise in liquidus temperature; however, the solidus temperature of the slag remains almost constant. The most important industrial characteristics of the slag (copper loss to the slag phase and foaming behaviour of the material) are definitely affected by such changes in slag composition and physical properties. Influence of alumina on these two phenomena were not investigated experimentally in the current work, but discussed, theoretically, based on the available literature. Mineralogical studies of the semi-rapidly solidified samples reveal that alumina addition to this type of slag changes the composition and concentration of major phases that are present in the material, which directly controls the leachability of different elements from the slag. It was found that in the current system, spinel and anorthite are the most leaching resistant phases, which are followed by olivine, clinopyroxene and orthopyroxene, respectively. Therefore, among the investigated samples in this study, the mixture of slag with 10 wt-% alumina addition shows the lowest leachability of most of the elements. As expected, by changing the cooling condition of the samples (i.e. water granulation), a totally different dissolution rate of the elements was observed. It is shown that leaching of the generated amorphous structures is a complex phenomenon that is controlled by other mechanisms than that of the semi-rapidly cooled samples.

  • 6.
    Mostaghel, Sina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Influences of alumina on fayalite-type slags properties: an experimental study on leaching and melting behaviours2010Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Recycling of secondary raw materials by non-ferrous metal producers is steadily increasing. These materials inevitably introduce various impurities to the production furnaces, which can change the chemical composition, and thereafter, the physical and chemical properties of the products and by-products.Alumina is one of the most common and significant impurities that enters the furnaces in different ways. Finding a balance between the recycling advantages and possible adverse effects of the increased alumina content in the process is of great interest to the metals industry.In the current work, effects of alumina on two of important properties (melting and leaching behaviours) of an actual industrial fayalite slag, from a Swedish copper producer, is investigated.A reference slag sample, devoid of alumina addition, and three different mixtures of slag with 5, 10, and 15 wt-% alumina addition were prepared. After homogenization (re-melting) of the mixtures, in an induction furnace, the materials were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). A standard single stage leaching test was used to study the leaching behaviour of the samples. Differential scanning calorimetry (DSC), Pt-Rh pans, was applied to investigate the melting and solidification properties of the mixtures.Results show that, olivine, spinel, and augite based solid solutions are the three main constituents of the samples. Addition of alumina to the slag increases the amount of spinel solid solution and changes its composition from iron rich to aluminum rich. The slag shows an alumina saturation limit between 5 and 10 wt-% alumina additions. Chemical composition of the major phases does not change above the saturation and excess amount of aluminum is consumed for formation of a new aluminum containing phase, anorthite. Below the saturation limit, alumina addition causes a relatively sharp increase in the melting temperature of the slag, and at the same time, an increase in the leached amounts of the elements is seen. Alumina addition, close to the saturation limit of the slag, lowers the leachability considerably, while the melting characteristics are not changed dramatically. However, above the saturation limit, a more complex transition occurs as the partial melting and leached amounts of most of the elements increase. In order to achieve an appropriate melting and leaching characteristics, the total alumina content of the slag must be close to its saturation limit. The grounds and influential parameters on such behaviours are thoroughly discussed.

  • 7.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Engström, Fredrik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Björkman, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Stability of spinels in a high basicity EAF slag2011Inngår i: Ferrous Slag-Resource Development for an Environmentally Sustainable World: Proceedings of the 6th European Slag Conference, 20-22 October 2010, Madrid, Spain, 2011, Vol. 5, s. 147-156Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Due to environmental regulations, steel producers in Europe, are obliged to reduce the amount of landfilled material, which is mainly slag. By fulfilling technical and environmental criteria, slag can be used in civil engineering applications. One of the most important environmental considerations is the leaching behaviour of the slag, especially with respect to chromium. A considerable research effort has been devoted to decrease the leaching of chromium from the slags by forming stable spinel phases. Most of the existing work focused on spinel forming agents. In this paper, influences of three different already formed spinels, in three different amounts, on an EAF slag from a low alloyed steel production are investigated. After re-melting and solidification, mineralogical properties of the samples were studied using scanning electron microscopy (SEM) and X-ray diffraction (XRD). Only one of the additives resulted in formation of distinguishable chromium rich spinels, which could immobilize chromium. The results are discussed by comparison with stable phases at equilibrium based on thermodynamic calculations.

  • 8.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Engström, Fredrik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Yang, Qixing
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Björkman, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    The effects of cooling rate on leaching behavior of some ferrous and non-ferrous slag systems2012Inngår i: Model Concept and Experiments: 9th International Conference on Molten Slags, Fluxes and Salts, Bejing 27-30 May 2012, 2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    It has been proven that pyrometallurgical slags can be given favorable physico-mechanical characteristics which make them suitable for use in civil engineering applications providing fulfillment of various technical and environmental criteria, of which slag leaching behavior is one of the main concerns. Numerous investigations have been carried out over the last several decades to clarify the influence of cooling rate on microstructure and properties of the slag systems; however, there is controversy in the literature as to the effect of rapid cooling, e.g. water granulation, on release of potentially toxic elements. In the current work, a ladle slag, a basic oxygen furnace (BOF) slag, two different electric arc furnace (EAF) slags, from low-alloyed and high-alloyed steel production, and three different “fayalite-type” slags, from zinc-copper smelting processes with different Fe/SiO2 ratios, are investigated. Semi-rapidly solidified (in crucible system) and water granulated samples for each composition were prepared. The solidified materials were characterized using commonly applied characterization techniques. The experimental work is compared with thermodynamic calculations using the FactSageTM thermodynamic package. Standard European leaching tests were carried out for all samples to investigate the slag leaching behaviors. Results show that rapid solidification and generated amorphous structure do not necessarily immobilize environmentally concerned elements in the glassy network. Instead, due to several factors, a higher reactivity is observed and trace elements dissolve more readily in the aqueous solution. The main reasons behind such a behavior including higher contents of metastable phases, different surface structures, oxidation and increased amount of grain boundaries are thoroughly discussed.

  • 9.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Holmgren, Hannes
    Boliden Mineral AB.
    Matsushita, Taishi
    Royal Institute of Technology.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Integrated recycling at Boliden's Rönnskär smelter: formation of slag products2012Inngår i: International Smelting Technology Symposium: Incorporating the 6th Advances in Sulfide Smelting Symposium / [ed] Jerome Downey; Thomas P. Battle; Jesse F. White, Wiley-TMS , 2012, s. 117-124Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Rönnskär Smelter of Boliden Mineral AB, Sweden, is a large end-processor of secondary raw materials and waste, including electronic scrap. E-scrap may introduce various impurities to the smelter’s flow-sheet, among which Al2O3 is a common and significant one. Current article summarizes the results of an ongoing research at Luleå University of Technology, Sweden, to study the influences of alumina on different properties of slag from the zinc fuming process at Rönnskär smelter. A combination of different experimental techniques and thermodynamic calculations has been used to investigate properties such as density, surface tension, effective thermal diffusivity, viscosity, melting and leaching behaviors. Results show that addition of alumina to this slag increases the degree of polymerization of the melt, and the properties vary correspondingly. Mineralogy of the semi-rapidly solidified samples is also changed due to alumina addition. A correlation between mineralogy and leaching behavior can be observed.

  • 10.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Matsushita, Taishi
    Kungliga tekniska högskolan, KTH.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Björkman, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Seetharaman, Seshadri
    Kungliga tekniska högskolan, KTH.
    Influence of alumina on physical properties of an industrial zinc-copper smelting slag: Part 1: Viscosity2013Inngår i: Transactions of the Institution of Mining and Metallurgy Section C - Mineral Processing and Extractive Metallurgy, ISSN 0371-9553, E-ISSN 1743-2855, Vol. 122, nr 1, s. 42-48Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The rotating cylinder method was applied to measure the viscosities of an industrial iron silicate slag and mixtures of this slag with 5, 10 and 15 wt-% alumina addition, in temperature range 1100–1300°C. The measured viscosities were compared with the predicted values using two of the commercially available software products for viscosity calculations, namely Thermoslag®1.5 and FactSageTM6.2. As the models can only predict viscosities for a solid free melt, obtained values by FactSageTM6.2 were modified using the Einstein–Roscoe equation. Results show that aluminium behaves as a network former cation in this type of slag, and by increasing the alumina concentration, the melt becomes progressively polymerised. Consequently, the viscosity of the slag increases at a given temperature, which is supported by thermodynamic predictions. According to the modified FactSageTM6.2 calculations, the viscosity of the solid containing slag increases from 2.1 to 5.5 poise at the industrial operating temperature (∼1250°C).

  • 11.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Matsushita, Taishi
    Kungliga tekniska högskolan, KTH.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Björkman, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Seetharaman, Seshadri
    Kungliga tekniska högskolan, KTH.
    Influence of alumina on physical properties of an industrial zinc-copper smelting slag: Part 2: Apparent density, surface tension and effective thermal diffusivity2013Inngår i: Transactions of the Institution of Mining and Metallurgy Section C - Mineral Processing and Extractive Metallurgy, ISSN 0371-9553, E-ISSN 1743-2855, Vol. 122, nr 1, s. 49-55Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Apparent density, surface tension and effective thermal diffusivity of an industrial iron–silicate based slag and mixtures of this slag with 5, 10 and 15 wt-% alumina addition were measured using the sessile drop and the laser flash techniques respectively. A comparison is made between corresponding values obtained from the commonly applied models and the experimental measurements. Results show that increasing the alumina concentration in slag increases the degree of polymerisation of the melt and, consequently, its effective thermal diffusivity. By alumina addition to the system, the surface tension increases progressively from 338 mN m−1, in the reference slag sample, to 488 mN m−1, in the mixture of slag and 15 wt-% alumina addition. The apparent density of the liquid–solid containing slag is continuously decreased due to the increased alumina concentration. However, the effect is more pronounced between 8 and 12 wt-% total alumina content in the slag.

  • 12.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Matsushita, Taishi
    Kungliga tekniska högskolan, KTH.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Björkman, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Seetharaman, Seshadri
    Kungliga tekniska högskolan, KTH.
    Influence of alumina on physical properties of an industrial zinc-copper smelting slag: Part 3: Melting behaviour2013Inngår i: Transactions of the Institution of Mining and Metallurgy Section C - Mineral Processing and Extractive Metallurgy, ISSN 0371-9553, E-ISSN 1743-2855, Vol. 122, nr 1, s. 56-62Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A combination of different experimental techniques and thermodynamic calculations has been used to investigate the melting behaviour of an industrial iron silicate slag and mixtures of this slag with 5, 10 and 15 wt-% alumina addition. Differential scanning calorimetry (DSC) and thermooptical observation were applied to monitor the solidus temperature and softening behaviour of the samples respectively. Estimation of the liquidus temperature was made using the second derivative of activation energies for viscous flow, with respect to temperature. All experimentally detected values were compared to predictions made using the FactSageTM6.2 thermodynamic package. Results show that as the slag lies in the fayalite primary phase field, the liquidus temperature decreases due to the increased alumina concentration. In the hercynite primary crystallisation phase field, however, alumina addition to the system increases the liquidus temperature. The solidus temperature does not vary significantly due to the current changes in the total alumina content of the slag.

  • 13. Mostaghel, Sina
    et al.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Metallurgical use of glass fractions from waste electric and electronic equipment (WEEE)2010Inngår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 30, nr 1, s. 140-144Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Within the European Union, it is estimated that between 8 and 9 million tonnes of waste electric and electronic equipment (WEEE) arises annually, of which television sets and computers account for an important part. Traditionally, Cathode Ray Tubes (CRT) have been used for TVs and computer monitors, but are rapidly being replaced by flat-screen technology. Only part of the discarded CRT glass is being recycled. Primary smelters use large amounts of silica flux to form iron-silicate slag, and can, in most cases, tolerate lead input. Use of discarded CRT glass in copper smelting is a potential alternative for utilization of the glass.The mineralogical composition of a slag sampled during ordinary slag praxis has been compared with that of a mixture of slag and CRT glass when re-melted and slowly cooled. Slag (iron-silicate slag) from Boliden Mineral AB, Sweden, was used for the experiments. Slag and glass have been mixed in various proportions: pure slag, pure glass, 90% slag-10% glass and 65% slag-35% glass, and heated in an inert atmosphere up to 1400 °C in a Netzsch Thermal Analysis (TA) instrument. The re-melted material has been analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM) to determine changes in mineralogical composition after mixing with glass.The results show that the main mineralogical component of the slag is fayalite; the CRT glass is amorphous. The main crystalline phases of the slag do not change with addition of glass. An amorphous phase appears when the addition of glass is increased, which gives the sample a different structure.

  • 14.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Björkman, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Influence of alumina on iron-silicate slag properties2011Inngår i: Proceedings of European Metallurgical Conference EMC 2011: Copper, General Pyrometallurgy/ Vessel Integrity/ Process Gas Treatment, Germany: GDMB , 2011, Vol. 1, s. 291-305Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Application of electronic scraps as secondary raw materials in non-ferrous metal extraction intro-duces various impurities to the production furnaces. This may change the chemical composition, and thereafter, the physical and chemical properties of products and by-products of the metallurgi-cal operation. Alumina is one of the most common and significant compounds that is associated with most of the secondary raw materials. Balancing the recycling advantages and possible adverse effects of the increased alumina content in the process is of much interest to the metals producers. In this paper, effects of alumina on melting and leaching behaviors of an industrial iron-silicate (fayalite-type) slag, from a Swedish copper producer, are studied. A reference slag sample, devoid of alumina addition, and three different mixtures of slag with 5, 10, and 15 wt-% alumina addition were prepared. After homogenization (re-melting) of the mixtures, in an induction furnace, the ma-terials were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). A standard single stage leaching test was used to study the leaching behavior of the samples. Dif-ferential scanning calorimetry (DSC), using Pt-Rh crucibles, was applied to investigate the melting and solidification properties of the mixtures. Results show that, this slag has an alumina saturation limit between 5 and 10 wt-% alumina additions. Chemical composition of the major phases does not change above the saturation and excess amount of aluminum is consumed for formation of a new aluminum containing phase, anorthite. Alumina addition increases the melting temperature continu-ously, while the rate of increase changes. Alumina contents close to the saturation limit of the slag decrease the leachability considerably.

  • 15.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Björkman, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Influence of alumina on mineralogy and environmental properties of zinc-copper smelting slags2013Inngår i: International Journal of Minerals, Metallurgy and Materials, ISSN 1674-4799, E-ISSN 1869-103X, Vol. 20, nr 3, s. 234-245Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An iron-silicate slag, from a zinc-copper smelting process, and mixtures of this slag with 5, 10 and 15 wt-% alumina addition were re-melted, semi-rapidly solidified and characterized using scanning electron microscopy equipped with energy dispersive spectroscopy, and X-ray diffraction. The FactSageTM6.2 thermodynamic package was applied to compare the stable phases at equilibrium conditions with experimental characterization. A standard European leaching test was also carried out for all samples to investigate the changes in leaching behaviour due to addition of alumina. Results show that the commonly reported phases for slags from copper and zinc production processes (olivine, pyroxene and spinel) are the major constituents of the current samples. A correlation can be seen between mineralogical characteristics and leaching behaviours. The sample with 10 wt-% alumina addition, which contains high amounts of spinels and lower amounts of the other soluble phases, shows the lowest leachabilities for most of the elements.

  • 16.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Candy, Ian
    Hatch Ltd..
    Challenges with increased alumina concentration in the zinc-copper smelting slags2013Inngår i: COM 2013 hosted by MS&T13: Ralph LLoyd Harris Memorial Symposium, MetSoc , 2013, s. 457-467Konferansepaper (Fagfellevurdert)
    Abstract [en]

    End of life (EOL) electronics is known to be a valuable resource of base and precious metals, and its application as a secondary raw material in pyrometallurgical processes is steadily increasing. These types of materials inevitably introduce various impurities to the smelting furnaces, which may change the physical and chemical properties of the products and by-products of the operation. Alumina is one of the most common and significant oxide components associated with EOL electronics; therefore, its influences on different properties of the iron-silicate or fayalite-type slags are of particular interest to the non-ferrous metal producers. The current article summarizes the effects of an increased alumina concentration on slag thermo-physical properties (density, surface tension, viscosity, etc.). Operational difficulties, e.g. copper loss to the slag phase and foaming of the melt, resulting from such a change in slag composition are also discussed.

  • 17. Mostaghel, Sina
    et al.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Lehner, Theo
    Effects of Al2O3 on mineralogy of the fayalite slag2008Inngår i: REWAS 2008: Global Symposium on Recycling, Waste Treatment / [ed] B. Mishra; C. Ludwig; S. Das, Minerals, Metals & Materials Society, 2008, s. 977-982Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Ronnskar smelter of Boliden Mineral AB, Sweden, is well known for recycling of base and precious metals. Slag from the electrical furnace is processed at the fuming plant to produce zinc clinker. The granulated slag is a by-product used as e.g. construction material. In this paper, influences of Al2O3 on mineralogy of the slag, which can affect its chemical and physical properties, are investigated. Different mixtures of Al2O3 /fumed slag were prepared. Re-melting was carried out in a Thermo-Gravimetry (TG) furnace with an inert atmosphere. Scanning electron microscopy (SEM) and X-ray diffractometer (XRD) were then applied for the analyses. Investigations depict that addition of alumina to slag, results in an increase in the number of spinels and a transformation from iron rich to aluminum rich spinels. Anorthite (CaAl2S2O8) will also be formed.

  • 18.
    Mostaghel, Sina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Yang, Qixing
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Mineralteknik och metallurgi.
    Recycling of cathode ray tube in metallurgical processes: Influence on environmental properties of the slag2011Inngår i: Global Journal of Environmental Science and Technology, ISSN 2248-9630, Vol. 1, nr Artikelnr: 19Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A potential recycling rout for the end-of-life cathode ray tubes (CRT) is its application as a fluxing material in lead and copper smelting processes. Therefore, a thorough study on possible effects of the additional CRT on products and by-products of the metallurgical operation is required. In this paper, influences of CRT addition on mineralogy and leaching behaviour of a fayalite-type slag from a Swedish copper producer are investigated. Mixtures of slag/CRT, in different fractions, were prepared and re-melted in a Tamman furnace. Materials characterization using scanning electron microscopy (SEM) and X-ray diffraction (XRD), and standard leaching tests were done for all samples. Results depict that the main crystalline phase of the slag does not change due to CRT addition. By 10 wt-% CRT addition, leachability of major elements decreases; whereas, that of some minor elements increases. With 35 wt-% CRT addition, leaching of some environmentally detrimental elements make the material unacceptable for construction purposes according to the regulations.

1 - 18 of 18
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf