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  • 1.
    Abrahamsson, Filip
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Leaching of Pyrrhotite from Nickel Concentrate2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Non-oxidative acid leaching of pyrrhotite from Kevitsa’s Ni-concentrate and methods to recover by-products, have been investigated. Selective dissolution of pyrrhotite (Fe1-xS, 0<x<0.25) can enrich the content of the valuable metals, such as Ni and Co, in the final concentrate and will reduce the amount of Fe and S sent to the smelters. The pyrometallurgical smelting of leached concentrate will thus give less formation of smelter by-products in form of slag and SO2. The leaching was studied through an experimental design plan with parameter settings of  38.8% to 57.8% H2SO4 and temperatures from 60 to 100°C. The best results were obtained in experiments carried out at the lower experimental range. Leaching at 60°C with an initial acid concentration of 38.8% H2SO4 was found sufficient to selectively dissolve most of the pyrrhotite; leaving an enriched solid residue. A QEMSCAN analysis of the solid residue confirmed that most of the pyrrhotite had been dissolved and showed that pentlandite was still the main Ni-mineral. Chemical assays showed that more than 95% of the Ni, Co, and Cu remained in the final residue.

       The utilized leaching process generates by-products, in the form of large quantities of Fe2+ in solution and gaseous H2S. To recover Fe2+, crystallization of iron(ii) sulfate (FeSO4∙nH2O) from leach solution through cooling have been studied. The crystallized crystals were further dehydrated into the monohydrate (FeSO4∙H2O) through a strong sulfuric acid treatment (80%H2SO4). XRD analysis confirmed that FeSO4∙H2O was the main phase in the final crystals, and a chemical analysis showed a Fe content of about 30%, 1.5% Mg, 0.4% Ca, and 0.2% Ni.

       The possibility to leach the concentrate by circulating the acidic solution from the crystallization stage has been tested. The recirculation of the solution showed no negative effects, as the recoveries of elements and chemical assays of the final solid residue were found to be similar to the obtained assay when the concentrate was leached in a fresh solution.

  • 2.
    Alakangas, Lena
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Hanna, Kaasalainen
    Sweco.
    Maurice, Christian
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Nyström, Elsa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Nigeus, Susanne
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    StopOx: UTILIZATION OF INDUSTRIAL RESIDUALS FOR PREVENTION OF SULFIDE OXIDATION IN MINE WASTE2019Report (Other academic)
    Abstract [en]

    This report is the outcome of the SIP STRIM project

    StopOx-Utilization of industrial residuals for prevention of sulfide oxidation in mine waste implemented at Applied geochemistry, Luleå University of Technology running from 2015 to 2018. Boliden Mineral has been partner and co-funder of the project. Other partners in the project were Cementa, Dragon Mining, MEROX, Nordkalk, and SP Processum. The overall aim of the project was to develop prevention technologies to reduce the sulfide oxidation in mine waste, during and after operation, and thereby reduce the generation of acid mine drainage. The StopOx project has been focusing on sulfidic mine waste from the Boliden area which were disposed of and are causing acid mine drainage or have the potential. Industrial residues/products were supplied by BillerudKorsnäs, Cementa, MEROX, and Nordkalk. The report consists of chapters based on three subprojects.

    Chapter 1. Introduction

    Chapter 2. Inhibition technology with aim to minimize waste rock oxidation during operations by using residues from other industries (passivation of sulfidic surfaces by the formation of secondary minerals)

    Chapter 3. The suitability of green liquor dregs as substitutes for or additives to till in a sealing layer as part of a cover system

    Chapter 4. Weathering of waste rock under changing chemical conditions

    The research described in chapters 2 and 3 was performed by Ph.D. students and will continue until 2021, while the subproject in chapter 2 ended in 2018.

  • 3.
    Al-Douri, Yamur K.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Hamodi, Hussan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Data imputing using generic algorithms (GA)2017In: Mine Planning and Equipment Selection (MPES 2017): Proceeding of the 26th International Symposium on Mine Planning and Equipment Selection Luleå, Sweden, August 29-31, 2017 / [ed] Behzad Ghodrati, Uday Kumar, Håkan Schunnesson, Luleå: Luleå tekniska universitet, 2017, p. 205-208Conference paper (Refereed)
  • 4.
    Amara, Sofiane
    et al.
    Unité de Recherche Matériaux et Energies Renouvelables (URMER) Université de Tlemcen, BP 119 Tlemcen, ALGERIA.
    Baghdadli, T
    Unité de Recherche Matériaux et Energies Renouvelables (URMER) Université de Tlemcen, BP 119 Tlemcen, ALGERIA.
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering. LTU.
    Planned Investigation of UTES Potential in Algeria2019In: Proceddings of the 2nd International Conference on Green Civil and Environmental Engineering (GCEE 2019) 4 - 6 September 2019, Atria Hotel Malang, Indonesia, 2019Conference paper (Other academic)
    Abstract [en]

    The unbalance between supply and demand of heat can be managed by thermal energy storage (TES). For large-scale systems the underground is used as storage medium or storage volume. Aquifer storage (ATES) is most suitable for very large applications, Borehole storage (BTES) the most general system in all scales and the rock cavern storage (CTES) is best suited for extremely high loading/extraction loads. The construction of any of these systems requires knowledge about site-specific properties of the ground i.e. geology and groundwater conditions. Current paper gives a brief review of the potential and advantage of CTES technology utilization in buildings for the hard climate.

  • 5.
    Amofah, Lea Rastas
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Maurice, Christian
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Bhattacharya, Prosun
    Department of Land and Water Resources Engineering, Royal Institute of Technology.
    The influence of temperature, pH/molarity and extractant on the removal of arsenic, chromium and zinc from contaminated soil2011In: Journal of Soils and Sediments, ISSN 1439-0108, E-ISSN 1614-7480, Vol. 11, no 8, p. 1334-1344Article in journal (Refereed)
    Abstract [en]

    Purpose: Normal soil washing leave high residual pollutant content in soil. The remediation could be improved by targeting the extraction to coarser fractions. Further, a low/high extraction pH and higher temperature enhance the pollutant removal, but these measures are costly. In this study, the utility of NaOH, oxalate-citrate (OC) and dithionite-citrate-oxalate (DCO) solutions for extracting of arsenic, chromium and zinc from contaminated soil were assessed and compared. In addition the effects of NaOH concentration and temperature on NaOH extractions, and those of temperature and pH on OC and DCO extractions, were evaluated. Materials and methods: A two-level, full-factorial design with a centre point was implemented. Two factors, concentration and temperature,were evaluated in NaOH extractions, and pH and temperature for OC and DCO solutions. In all cases, the extraction temperature was 20°C, 30°C and 40°C. The studied NaOH concentrations were 0.05, 0.075 and 0.1 M. The pH in OC solutions was 3, 5 and 7, and in DCO solutions, 4.7, 6.3 and 6.7. Water-washed and medium coarse soil fraction of arsenic, chromium and zinc contaminated soil was agitated for 15 min with the extraction solution. Results and discussion: In NaOH extractions, the temperature and (less strongly) NaOH concentration significantly affected As and Cr mobilisation, but only the latter affected Zn mobilisation. Both pH and temperature significantly (and similarly) influenced As and Cr mobilisation in OC extractions, while only the pH influenced Zn mobilisation. In contrast, the extraction temperature (but not pH) influenced As, Cr and Zn mobilisation in DCO extractions. Conclusions: For all extractants, mobilisation was most efficient at elevated temperature (40°C). None of the extractants reduced the soil's As content to below the Swedish EPA's guideline value. Use of DCO is not recommended because dithionite has a short lifetime and residual arsenic contents in DCO-extracted soil are relatively high. Instead, sequential extraction with NaOH followed by OC solutions (affording significant reductions in As, Cr and Zn levels in the soil with short extraction times) at 40°C is recommended

  • 6.
    Andreas, Lale
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Aktivitet: Seminarium om användning av slam och aska som tätskikt på deponi2005Conference paper (Other (popular science, discussion, etc.))
  • 7.
    Andreas, Lale
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Hydrotermisk karbonisering: en praktisk avfallsbehandlingsmöjlighet?2017Report (Other (popular science, discussion, etc.))
    Abstract [en]

    Hydrothermal carbonization (HTC) is a treatment where an organic material is subjected to a combination of heat and pressure, for example 200°C and 20 bars. Then nutrients are dissolved and the structure of the material is changed, leading to a stabilization and comminution, and making it easier to separate from the inorganic materials. Previously HTC has been used mostly for fuel production, but in this study the potential for detoxification and separation of wastes is in focus, and what role HTC can play as a waste management method. The purpose is to judge the potential of HTC as a method to increase recycling of nutrients in a circular economy with a simultaneous increased detoxification compared to biological treatment, and less emissions of carbondioxide trough other uses of organic materials than as fuel.

    To achieve these goals a lab experiment was done with subsequent chemical analyses, and the results provided a basis for a multivariate analysis and a life cycle assessment (LCA). The results shows a detoxification trough a separation of the amounts of hazardous heavy metals and that there is an increase in heating value. However, the processed material cannot be used as a soil improver or as a construction material, but this is due to the fact that it was already contaminated.

    HTC is most suitable for wet, organic, mixed wastes. A market analysis shows that 100 000's tons of these wastes are produced every year in Sweden.

    To sum up, the process can be interesting as a waste management method, however more research is needed on the mechanical properties and separation of the material.

  • 8.
    Andreas, Lale
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Implementing a lab-developed liner recipe in a full scale cover construction: challenges, setbacks and success2012In: Abstract proceedings of 7th Intercontinental Landfill Research Symposium: Södra Sunderbyn, June 25th to 27th, 2012 / [ed] Anders Lagerkvist, Luleå: Luleå tekniska universitet, 2012, p. 40-Conference paper (Refereed)
  • 9. Andreas, Lale
    Langzeitemissionsverhalten von Deponien für Siedlungsabfälle in den neuen Bundesländern2000Doctoral thesis, comprehensive summary (Other academic)
    Abstract [de]

    Langzeitemissionsverhalten von Deponien für Siedlungsabfälle in den neuen BundesländernZusammenfassungZiel der vorliegenden Arbeit war die Beschreibung des Langzeitverhaltens von DDR-Depo­nien unter besonderer Berücksichtigung der Emissionen auf dem Sickerwasserpfad.Die Beschreibung umfaßte die untersuchten Deponiestandorte, die Deponierungspraxis in der DDR, cha­rak­teristische Eigenschaften der abgelager­ten Abfälle sowie der nach mehrjähriger Lage­rungs­zeit ausgekofferten Altabfallproben, die Sickerwasseremissionen der Deponie Döbeln-Hohenlauft, das Auslaugverhalten der Altabfälle in Mehrfachelutionsversuchen und die Sickerwasser- und Gas­emis­­sionen der Deponiesimulationsversuche.Als charakteristische Eigenschaften der DDR-Deponien, die für das Emissionsverhalten von Be­deu­tung sind, wurden folgende Punkte herausgearbeitet:langsames Deponiewachstum,fehlende oder sehr geringe Verdichtung,vergleichsweise intensive aerobe Prozesse zu Beginn der Ablagerung.Bedingt dadurch wurde ein Großteil der biologisch abbaubaren Bestandteile des Abfalls sehr schnell umgesetzt und trägt nicht zum langfristigen Emissionsverhalten bei.Die Abfallzusammensetzung von DDR-Altabfällen ist gekennzeichnet durch:hohe Anteile von Feinmaterial (bis zu 70 Masse% sind < 8mm),hohe Anteile mineralischer Stoffe, wie Aschen und Bauschutt,hohe Salzgehalte (Sulfat, Alkalien, Erdalkalien),eine hohe Säurepufferkapazität undgeringe Anteile organischer Abfälle.Dies führt zu einem wenig reaktiven Deponiekörper und den bei den meisten alten DDR-Depo­nien zu beobachtenden geringen Emissionen. Die wesentlichen Emissionen erfolgen auf dem Sicker­was­serpfad, die Hauptkomponente dabei sind anorganische Salze. Hinsichtlich der Zu­sam­mensetzung kön­nen die DDR-Deponien am ehesten mit Asche-/Schlackedeponien verglichen werden, die in Zu­kunft den wohl wichtigsten Deponietyp in Deutschland darstellen werden.Auf der Basis der Untersuchungen zur Feststoffzusammensetzung der Abfälle und ihres Auslaug- und Emissionsverhaltens wurden desweiteren Prozesse diskutiert, die in DDR-De­po­nien in der Ver­gan­genheit stattgefunden haben können bzw. die zukünftig möglich sind. Hierbei sind zu nennen:die Auslaugung von Salzen,Sulfatreduktion,Karbonatanreicherung im Feststoff.Mittels multivariater Datenanalyse konnte eine Einordnung der Deponieprozesse in eine späte an­aero­be Phase mit Tendenz zu semi-aeroben Prozessen hin vorgenommen werden. Die methodischen Unterschiede zwischen Mehrfachelutions- und DSR-Versuchen wurden genutzt, um biologische Prozesse in den DSR zu identifizieren und bewerten. Im Ergebnis der Untersuchungen in Deponiesimulationsreaktoren wurden langfristige Emissions­poten­tiale EP und notwendige Nachsorgezeiträume bis zum Erreichen von Grenzkonzentrationen im Sickerwasser abgeschätzt. Sie sind in Tabelle 1 als Medianwerte zusammengefaßt dargestellt. Die Auswertung langjähriger Sickerwassermeßreihen der Deponie Döbeln-Hohen­lauft bestätigte die Repräsentativität der DSR-Versuche und unterstützt die getroffenen Progno­sen.Tabelle 1 Notwendige Zeiträume TE bis zum Erreichen von umweltverträglichen Konzentra­tio­nen cE im Sickerwasser von DDR-Altdeponien [a] Grenzkonzen­tration cEDSR-EP(W-F ® ∞) Stoffaustrag FE bis cE [g/kg] W-FE bis cE [l/kg TS] Zeitraum TE bis cE [a]CSB200 mg/l0,60,20,557TOC 100 mg/l0,150,040,334NKj 70 mg/l0,250,091,2144Cl‾100 mg/l0,70,61,4167SO42‾250 mg/l2,72,61,5180 Die längsten Zeiträume sind für den Austrag von Stickstoff und Salzen, insbesondere des Sulfats, notwendig. Die Dauer wird im wesentlichen durch folgende Faktoren beeinflußt:Abfallzusammensetzung (Anteil neuer Abfälle auf den alten DDR-Deponien)WasserhaushaltLuftzutritt, Oxidation.Ein Ausblick auf das veränderte Emissionsgeschehen der nach 1990 weiter ­betriebenen DDR-Deponien zeigt, daß sich durch die Veränderungen in Ab­fall­zusam­men­setzung und Abla­ge­rungs­praxis das Deponieverhalten deutlich verschlechtert hat, und eine Annäherung des Emis­­sions­­niveaus an die Verhältnisse von Siedlungsabfalldeponien der 70er/80er Jahre in den alten Bun­des­län­dern zu verzeichnen ist.Die erwarteten Nachsorgezeiträume gehen z. T. deutlich über heute in der Praxis diskutierte Werte hinaus. Um den Zeitrahmen bis zum Erreichen umweltverträglicher Sickerwasserkonzentrationen so zu verkürzen, daß die bei der Deponierung anfallenden Probleme von der gleichen Generation gelöst werden, die sie verursacht hat, sind aktive Maßnahmen zur Emissionsminimierung unbedingt not­­wendig.

  • 10. Andreas, Lale
    et al.
    Bilitewski, Bernd
    University of Technology Dresden, Pirna.
    Effects of waste quality and landfill technology on the long-term behaviour of municipal landfills1999In: Waste Management & Research, ISSN 0734-242X, E-ISSN 1096-3669, Vol. 17, no 6, p. 413-423Article in journal (Refereed)
    Abstract [en]

    The pollution potential of old municipal landfills of the former German Democratic Republic (GDR) is not as bad as expected, even taking into consideration that most lack environmental protection systems. Compared with specific conditions in the former GDR (such as production and consumption), the disposal of waste and the long-term behaviour of landfills clearly differs from that in the old German federal states. Low quantities of deposited waste created slowly growing landfills, and therefore led to rapid degradation processes still in the aerobic milieu. As a result of the increasing similarity of waste quantities and composition in the new and old federal states after 1990, waste deposited today can be expected to have similar long- term behaviour and emissions as existing old Federal Republic of Germany (FRG) landfills which were operating during the 1970s and 1980s.

  • 11.
    Andreas, Lale
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Diener, Silvia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Hydraulic performance of a land-fill top cover based on steel slag2014In: Sardinia 2013: 14th International Waste Management and Landfill Symposium, Forte Village, S. Margherita di Pula (CA), Italy, 30 September - 4 October 2013 ; CD-ROM: Symposium proceedings / [ed] Raffaello Cusso, Cagliari: CISA, Environmental Sanitary Engineering Centre , 2014Conference paper (Other academic)
    Abstract [en]

    HYDRAULIC PERFORMANCE OF A LAND¬FILL TOP COVER BASED ON STEEL SLAGThe steel industry is expanding and following the amount of produced steel, more and more by-products and residuals are generated. About 17.6 million tonnes of steel slags arise in Europe every year. In Sweden about 18 % of the iron- and steelmaking slags are landfilled (Jernkontoret, 2012). One application for steel slags are landfill covers where large amounts of virgin materials are needed. The legal requirement in Sweden is directed towards the maxi¬mum amount of lea¬chate generated at the bottom of the landfill: < 5 and < 50 l (m2*a)-1 for landfill class 1 and 2, respec¬ti¬vely. To secure these demands, a layer of low permeability is needed to reduce water infiltration. The hydraulic load of this layer ought to be controlled by a protective water balance layer and an effective drainage layer.Previous investigations indicate that steel slags can be used as construction material for both liner and drainage layer (Herrmann et al., 2010). In order to verify this in full scale, five tests areas (A1-5) were constructed at a municipal landfill in Sweden between 2005 and 2011. The areas were designed using different mixtures of steel slags from the local steel company in the liner. The purpose of this study was to evaluate the hydraulic performance of the cover during the first years after installation.The design of the cover construction was varied like this: a mixture of 50 % electric arc furnace slag (EAFS) and 50 % ladle slag (LS) was tested as liner material in the first test area (A1). A2 and A3 were built using less LS and coarser fractions of EAFS since laboratory tests had given satisfactory results also for these recipes. High infiltration rates in A2 and 3 led to a return to the original weight proportions in A4 and 5, yet another EAF slag was introduced in these areas. The mixing and construction techniques were refined during the first years of the project time: while A1 was built with rather poorly conceived technique, as of A3 the method can be considered as technically mature and approved.The liner performance was evaluated by lysimetry: 10 lysimeters were installed below each test area. The infiltration below the liner corresponded to 44, 74, 71, 19 and 0.4 l/m2*year for A1 to A5. Compared to the legal limit of 50 l/m2*year, the covers of A2 and A3 allowed about 50 % more water to enter the landfill than stipulated.An initial increase of the infiltration was observed, which most likely is related to increasing water saturation of the liner material in the first period after construction. The saturation occurred fastest in A2, where basically no initial increase was observed, probably due to the long time that elapsed between construction and the first sampling event (260 days). In contrast, the saturation in A1 and A4 was quite slow which can be related to the smaller particle size of the slags in these areas and, hence, a less porous liner material. The decrease in A2 and A3 might be explained by mineral transformations within the slag matrix such as carbonation of calcium and magnesium leading to the precipitation of carbonates in the pores of the liner material. Future observations will show if the decreasing trend in A2 and A3 remains such that the infiltration eventually reaches a level falling below the legal limit.The results show that the infiltration criteria can be fulfilled under the condition that at least 50 % of the liner mix consists of ladle slag, a fine-grained slag with cementitious properties. With few adaptations the steel slag can be used with standard construction processes.

  • 12.
    Andreas, Lale
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Diener, Silvia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Steel slags in a landfill top cover: Experiences from a full-scale experiment2014In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 34, no 3, p. 692-701Article in journal (Refereed)
    Abstract [en]

    A full scale field study has been carried out in order to test and evaluate the use of slags from high-alloy steel production as the construction materials for a final cover of an old municipal landfill. Five test areas were built using different slag mixtures within the barrier layer (liner). The cover consisted of a foundation layer, a liner with a thickness of 0.7 m, a drainage layer of 0.3 m, a protection layer of 1.5 m and a vegetation layer of 0.25 m. The infiltration varied depending on the cover design used, mainly the liner recipe but also over time and was related to seasons and precipitation intensity. The test areas with liners composed of 50% electric arc furnace (EAF) slag and 50% cementitious ladle slag (LS) on a weight basis and with a proper consistence of the protection layer were found to meet the Swedish infiltration criteria of ⩽50 l (m2 a)−1 for final covers for landfills for non-hazardous waste: the cumulative infiltration rates to date were 44, 19 and 0.4 l (m2 a)−1 for A1, A4 and A5, respectively. Compared to the precipitation, the portion of leachate was always lower after the summer despite high precipitation from June to August. The main reason for this is evapotranspiration but also the fact that the time delay in the leachate formation following a precipitation event has a stronger effect during the shorter summer sampling periods than the long winter periods. Conventional techniques and equipment can be used but close cooperation between all involved partners is crucial in order to achieve the required performance of the cover. This includes planning, method and equipment testing and quality assurance.

  • 13. Andreas, Lale
    et al.
    Ecke, Holger
    Shimaoka, T.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Characterizing landfill phases at full-scale with the aid of test cells1999In: Sardinia 99: proceedings / Seventh International Waste Management and Landfill Symposium, [4 - 8 October 1999, S. Margherita di Pula, Cagliari, Sardinia, Italy]. / [ed] Thomas H. Christensen, Cagliari: CISA, Environmental Sanitary Engineering Centre , 1999, Vol. 1, p. 145-152Conference paper (Refereed)
  • 14.
    Andreas, Lale
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Jannes, Sara
    Telge Återvinning AB.
    Mellström, Anna
    Telge Återvinning AB.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Tham, Gustav
    Telge Energi AB.
    Chemical and hydraulic conditions in a landfill/deposit for wood-based ash2004In: The 3rd Intercontinental Landfill Research Symposium November 29th - December 2nd, 2004 in Toya, Hokkaido Japan / [ed] Morton Barlaz; Anders Lagerkvist; Toshihiko Matsuto, Hokkaido: Center for Applied Ethics and Philosophy, Hokkaido University, 2004, p. 121-129Conference paper (Other academic)
  • 15. Andreas, Lale
    et al.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Mácsik, Josef
    Ecoloop, Stockholm.
    Tham, Gustav
    Telge AB.
    Use of secondary materials in landfill constructions2007In: SARDINIA 2007: Eleventh International Waste Management and Landfill Symposium ; [1 - 5 October 2007, S. Margherita di Pula, Cagliari, Sardinia, Italy] / [ed] Raffaello Cossu, Cagliari: CISA, Environmental Sanitary Engineering Centre , 2007Conference paper (Refereed)
    Abstract [en]

    Many landfills are subject to closure in the near future. Roughly 2,000 hectares of land­fill area have to be covered only in Sweden, equivalent to about 100 million tonnes of construction material. In addition to material costs in the order of tens of billions Euro, this also puts a strain on the environment through the exploitation of non-renewable virgin construction materials. Many landfill operators are considering alternative cover designs and materials in order to reduce resource spending. However, there is a fair amount of uncertainty with regard to functional and environmental consequences of using alternative (secondary) materials, both from the side of the companies and the authorities. This paper gives an overview over potential waste based construction materials and the use of some of them in projects presently ongoing in Sweden.Research on the use of secondary materials in landfill covers is quite recent. Substitutes for natural or synthetic materials in a landfill cover can be various types of waste from process industry, construction and demolition, or comparable activities. Alter­na­tive mate­rials that have been investigated are ashes, slags, sewage and fibre sludges, treated soils and com­post. Table 1 gives an overview over potential waste based construction materials. The total of potential materials is well in excess of the material needs for landfill construction, but they may not be available at the right time, place or quality.Besides being economically viable, the substitute materials should have suitable technical and environmental properties in order to secure a proper function of the construction. Experiences from three field studies (landfills at Tveta/Södertälje, Hagfors and Alvkarleby) are discussed looking at relevant issues during 1) construction, 2) active after care phase, and 3) long term processes.Using SCM poses additional problems compared to using conventional materials. Often, the supply of material has to be planned in advance and the materials may have to be stored on site. Storing, however, can cause problems if the materials have properties that change over time e.g. due to climate. For other materials storing may be necessary in order to achieve desired properties. One example is the ageing of strongly alkaline materials that react with atmospheric carbon dioxide and thus obtain better leaching properties. Table 1 Overview over potential waste based construction materials and examplesSourceExamplesMining and mineral industryWaste rock, flotation sand, etc...Construction and demolition (C&D)Crushed concrete, gypsum, asphalt, reinforced polymers, woodProcess industryDifferent types of slag from steel making, green liquor and fibre sludge from paper production, ashes and foundry wastesWastewater treatmentDigested sewage sludge, sandIncinerationBottom ash, fly ashThe evidence is mounting that the desired technical function of a landfill cover can be attained using suitable combinations of secondary construction materials. So far, all three field tests indicate leachate amounts between less then one and 30 l (m2 yr)-1 below the liner. In comparison with the average annual precipitation of about 600 mm yr-1 at the Swedish East coast, only 0.2-5 % of the precipitation seeped through the liner so far; i.e. the leachate generation is reduced with about 90 % or more.The issue is more if the materials may cause adverse impacts of the landfill and its recipients. A low water infiltration through the liner means that the most of infiltrating water is removed as drainage water and thus the leaching of the layers above the liner are of the greatest concern.Infiltrating water will yield a liquid to solid ratio of about 1-2 l kg-1 in the layers above the liner after about 10 years. The most mobile elements, such as nitrogen, will be leached to a great extent already at such low L/S ratios, so a forecast with regard to the need of treatment of drainage water points at about two to three decades.In the long term perspective the mineral changes of the construction materials become important. E.g. one of the incentives for using fly ash in liners is their capacity for chemical-mineralogical changes leading to the formation of clay-like structures. This could mean that a liner built of ashes will attain a lower permeability over time. Other mineral changes that can occur in ashes include the trapping of metals in the structure, e g in clay and carbonate phases.Much is still to be learned about the long term processes and the factors that control them. Ongoing studies include the assessment of climatic variables, different material combinations as well as the impact of landfill gases.The following conclusions can be drawn:The use of secondary materials in construction is important due to substantial resource and environmental impacts. An increased use should be beneficial, provided that the problems of using such materials can be managed.In addition to legislative and bureaucratic barriers, there are also practical issues which need to be dealt with in order to pave the way for a wider use of alternative construction materials. In the construction phase more planning is needed due to temporal and geographical limitation of the material availability. Some materials are not ready for immediate use but need to be pre-treated. All of these factors may cause a need for more space and time. A system for quality assurance comparable to that of traditional construction materials is another issue that needs to be resolved. Most likely some kind of legislative pressure is needed for this.In the medium term leaching of pollutants from the construction materials may be the most important issue when using secondary construction materials, which underlines the double standards applied, since traditional construction materials will not be scrutinized in the same manner. Anyhow, the long term interactions between materials and their environment need to be considered and further studies are necessary for secondary construction materials as well as for conventional materials. Existing data indicate both possibilities and problems.In the long term issues of material interactions will remain and the mechanical impact of mineral changes in the secondary construction materials may be added to the list of issues to clarify. Some of the material changes may be beneficial for the function of the construction, e.g. clay formation in liner materials may make them more impervious, but there may also be negative changes caused by deteriorated material properties. The rate and extent of such processes and the factors that enhance or retard them need to be understood better.Secondary construction materials have always been used and some of the "traditional" materials used today were wastes before. There is no reason to believe that this development should not continue.

  • 16.
    Andreas, Lale
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Tham, Gustav
    Telge AB.
    Utvärdering av fullskaleanvändning av askor och andra restprodukter vid sluttäckning av Tveta Återvinningsanläggning2008Report (Other academic)
    Abstract [en]

    In 2000 Telge Återvinning - a waste management recycling company - started investigating ashes from incineration of industrial and biowaste waste. The company was given a permit from the Swedish Environmental Court to cover four hectares of the house hold waste landfill area. In 2006 the company received an unlimited permit to cover the remaining part of the landfill when the works end some thirty years later.Ashes were used the first time in 1966 for testing. Literature studies indicated the ashes can have a low hydraulic conductivity under certain conditions. In 1999 collaboration started with the Division of Waste Science and Technology at Luleå University of Technology.Residuals from household and industrial waste were subject to investigation. Initially, biowaste incineration products were subject to testing and were later extended to other waste products, e.g. sludge, contaminated soils, foundry, and compost material. Several different sub-fractions of ashes were included in the investigation e.g. bottom and fly ash, various slag products after up-grading including dewatering, separation and sifting. Subsequently, a complete covering system of a landfill consists of residuals.Six test areas were outlined in order to give a good representation for cover construction in flat and steep areas with different compositions of liner material.The results show that in all areas the hydraulic conductivity construction yields less then 50 liters per square meters and years and can be less the than 5 liters in a repository for hazardous waste if required. In accordance with literature data the field observations show the liner material constructed only by ash material under certain conditions can form a monolithic structure due to very slow processes thus indicating small pore volumes that unable water - air to interact with other media.The concept of using ash can be related to natural analogues of volcanic ashes and has been used in old defence walls and other buildings thousand years back. The last part of the report brings a number of topics for future research and a discussion about problems to with the authorities to use residuals for covering landfills.

  • 17.
    Andreas, Lale
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Travar, Igor
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Tham, Gustav
    Sweco AB.
    Leaching behaviour of ashes in a landfill cover construction2012In: Abstract proceedings of 7th Intercontinental Landfill Research Symposium: Södra Sunderbyn, June 25th to 27th, 2012 / [ed] Anders Lagerkvist, Luleå: Luleå tekniska universitet, 2012, p. 39-Conference paper (Refereed)
  • 18.
    Arm, Maria
    et al.
    Statens Geotekniska Institut.
    Vestin, Jenny
    Statens Geotekniska Institut.
    Lind, Bo
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Nordmark, Desiree
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Hallgren, Per
    Skogsstyrelsen.
    Pulp mill fly ash for stabilization of low-volume unpaved forest roads: field performance2014In: Canadian journal of civil engineering (Print), ISSN 0315-1468, E-ISSN 1208-6029, Vol. 41, no 11, p. 955-963Article in journal (Refereed)
    Abstract [en]

    Increased temperatures and rainfalls will give more settlements and less bearing capacity in gravel roads, which will have implications for the forestry. Pulp mill fly ash without additives was used for stabilizing the road base of a low-volume gravel road. A two-year monitoring of the road was conducted, including measurements of achieved ash content, density, water infiltration capacity, and load bearing capacity. The results showed that the ash-stabilized sections performed better than conventionally upgraded sections and also achieved increased bearing capacity over time. Hydration of the fly ash increased the stiffness and decreased the permeability of the road base. The differences were more pronounced during spring thaw. Best performance was achieved in the section with thicker ash stabilized layer.

  • 19.
    Ascher, J.
    et al.
    University of Florence.
    Ceccherini, M.T.
    University of Florence.
    Guerri, G.
    University of Florence.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Landi, L.
    University of Florence.
    Mench, Michel
    Bordeaux 1 University.
    Nannipieri, P.
    University of Florence.
    Pietramellara, G.
    University of Florence.
    Renella, Giancarlo
    University of Florence.
    Is microbial species richness increased by aided phytostabilization of trace element contaminated soils?2008Conference paper (Other academic)
  • 20.
    Asplund, Erik
    et al.
    inno Scandinavia AB.
    Lagerkvist, Anders
    Heydebreck, Peter
    inno AG.
    Dahlén, Lisa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Norberg, Anna
    Umeå universitet.
    Framsyn för Norrbotten och Västerbotten: en idéskrift om utvecklingsinsatser idag och imorgon2009Report (Other academic)
    Abstract [sv]

    Rapport från DARE delprojekt regional framsyn. Etapp 1; scenarier och förslag på aktiviteter.Detta dokument är slutrapporten från den regionala framsynsprocessen som drevs 2008-2009 inom projektet DARE – Development Arena for Research and Entrepreneurship.Framsynen har verkat efter ett normativt och handlingsinriktat angreppssätt. Ledmotiv för processen har varit frågor som: Hur vill vi ha det? Varför är det inte så nu? Vad behöver vi göra nu och i framtiden? Regionen kan sägas kännetecknas av att den är rik på naturresurser och fattig på folk. Det är bakgrunden till de fokusområden som framsynen behandlat- Grönare näringsliv (hur kan nya och miljöeffektivare produkter och tjänsterutvecklas effektivare?)- Demografiutveckling (hur kan samhällsfunktionerna bestå med inverteradebefolkningspyramider och hur kan utvecklingen mot en åldrande befolkningvändas?)Lite tvärs över båda frågorna ovan hamnar ett annat fokus; regionens attraktivitet. Inom detta område har en ung framsyn genomförts med deltagare från olika delar av Norrbotten.Framsynen har gått steg för steg genom visioner, analys av framgångsfaktorer, scenarieskapande, förslag på åtgärder och prioritering av dessa. Under genomförandet har det uppstått ett antal avknoppningar i form av t ex nya samarbeten och projekt. Ett av de sistnämnda var den unga framsynen som genomfördes med finansiering av Norrbottens läns landsting.Bland de prioriterade förslagen som redovisas i denna rapport dominerar olika aktiviteter för att knyta samman olika aktörer och grupper inom regionen och på så sätt göra mer av mindre. Många av förslagen visar regionala aktörers förväntningar på universitetens roll i den regionala utvecklingen och markerar ett intresse av tätare samverkan meduniversiteten. Förslagen berör alla verksamheter inom universiteten, såväl utbildning, forskning och förvaltning. Bland de prioriterade förslagen finns:• Stimulera gröna affärs och teknikutvecklingsallianser för regionens småföretag• Stimulera ”den lille forskaren” – en modell för småföretagens forskarkollektiv• Utred grönare näringsliv som gemensamt profilområde för regionens universitet• Stärk företagsnyttig forskning & utvecklingsinsatser kring ”age management”• Etablera ett ”integrationsnätverk” för universitetens studenter & det regionalasamhället• Utveckla dialogen mellan universiteten & avnämargrupper i utvecklingen avutbildningar • Skapa regionalt utvecklingslab för bättre samverkan mellan universiteten ochomgivande samhälleInom DARE-projektet kommer nu det material som utvecklats inom framsynsprocessen att användas för utveckling av samverkan inom universiteten, mellan universiteten och med andra intressenter av den regionala utvecklingen, inte minst då de som deltagit i framsynen.

  • 21.
    Ataide Salvador, Dandara
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Geometallurgical Variability Study of Spodumene Pegmatite Ores, Central Ostrobothnia - Finland2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This geometallurgical variability study was conducted for Keliber Oy definitive feasibility study. It includes the Syväjärvi, Länttä and Rapasaari lithium ore deposits located in Central Ostrobothnia – Finland. These deposits present different characteristics in terms of spodumene grade, grain size, alteration, and weathering.

    A geometallurgical approach was used to characterize the ore and learn about the variability within and between the deposits in terms of mineralogy and processing response. In the project design chosen, grinding and flotation tests were performed. In addition, chemical composition of spodumene, mineralogical and liberation studies were carried out by MLA and EDS analysis.

    Spodumene is the main Li mineral in the deposits and its characteristics and elemental composition differ between and within these deposits, affecting mineral processing behavior. Spodumene impurities content as FeO and MnO are the highest in Länttä and lowest in Rapasaari. With respect to the harmful elements, Mg is carried by amphiboles and micas and P by apatite and sicklerite.

    Grinding is mainly influenced by the spodumene grade of the ore. The total grinding time to reach the P80 target was similar for the average ores, around 30 minutes of two stage grinding. Pre-flotation removed more than 50% of the apatite with on average 4.6% losses of spodumene. A cleaning stage for the pre-flotation product is recommended to recover some of the spodumene losses.

    In spodumene flotation with rougher and seven cleaning stages, Syväjärvi average ore showed high recoveries (about 90%) to final concentrate, whereas Länttä and Rapasaari presented clearly lower recoveries, (about 70%). In addition, Länttä presented the lowest spodumene grade in the final concentrate (about 70%) and Rapasaari the highest (about 75%). The flotation process, in general, turned out to be efficient in terms of concentrate grade, achieving, in most of the cases, the targeted Li2O grade of 4.5%. Although, the geometallurgical test is based on flowsheet developed for Syväjärvi and it is quite expected that Länttä and Rapasaari samples show poorer performance. Therefore, flotation tests and process optimization should be done to improve the spodumene recovery of Länttä and Rapasaari deposits. Considering Syväjärvi samples, spodumene head grade and grain size had positive effects in flotation. In contrast, spodumene alteration had a negative effect. Länttä shows lower spodumene liberation with given grind which leads to lower recovery and grade in flotation. A combination of lower feed grade, locking association, P80 and secondary Li minerals may explain Rapasaari samples performance. The weathered Rapasaari sample showed a positive effect on spodumene recovery which is possibly due to the liberation of spodumene grains from feldspars and quartz. Controlled waste dilution on ore samples promoted lower spodumene recovery and lower final concentrate grades, proportional to the dilution ratio. The results indicate that flowsheet and processing conditions as P80 and collector dosage need to be optimized by the deposit and by the ore type. Nevertheless, the present study is a diagnostic test and the results cannot be directly correlated to full-scale process.

  • 22.
    Backlund, Daniela
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Palmenäs, Jenny
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Termisk vattenavsaltning med industriell spillvärme: En förstudie om att avhjälpa sötvattenbristen på södra Öland genom att nyttja spillvärmen från Cementa i Degerhamn2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    År 2016 upplevde Öland historiskt låga grundvattennivåer, vilket skapade svårigheter för både allmänheten och jordbruket att tillgodose färskvattenbehovet. Tankbilar med sötvatten kördes från Kalmar till Öland för att stödja vattenförsörjningen. Därefter anlades även en vattenledning över Kalmarsund för att förstärka resurserna ytterligare. Öns begränsade grundvattenresurser är en kombination av geologiska och meteorologiska förutsättningar. Ön har ett tunt jordlager och ett utbrett spricksystem i berggrunden, vilket medför att mycket utav den nederbörd som faller över Öland avdunstar eller rinner ned i dessa sprickor. Årsmedelnederbörden på ca 500 mm är låg jämfört med andra ställen i Sverige. I och med ökningen av permanenta boenden, turism och jordbruk har vattenresurserna blivit än mer ansträngda.

    Syftet med denna studie var att undersöka om södra Ölands vattenbrist kan avhjälpas genom att på konstgjord väg infiltrera vatten från Kalmarsund till grundvattnet, efter att det avsaltats med hjälp av spillvärme från Cementas fabrik i Degerhamn. Syftet med konstgjord infiltration till grundvattnet är, förutom att använda marken som ett vattenmagasin, även en möjlighet att remineralisera vattnet, bidra till markstabilisering samt motverka saltvatteninträngning.

    Metoden var främst teoretisk i form av en litteraturstudie, beräkningar av spillenerginivåer samt modellering av grundvattenpåverkan vid infiltration. Inledningsvis genomfördes även ett platsbesök på Cementas fabrik på Öland för att överblicka deras process och kartlägga möjliga placeringsalternativ för spillvärmeuttag ur fabrikens processgaser.

    Resultaten från studien visade att spillvärmeuttaget bör ske antingen vid fabrikens kyltorn eller vid dess skorsten. Kyltornet erbjuder det maximala potentiella energiuttaget och därmed också högst produktionskapacitet av renat vatten, motsvarande 560 m3/dygn. Dock erbjuder skorstenen en billigare installation och underhåll av avsaltningsutrustningen tack vare mer utrymme och lägre partikelhalt i processgasen.

    Studien visade att det framställda destillatet skulle ha en positiv inverkan på Ölands grundvattennivåer, även de mängder som är mindre än 560 m3/dygn. Med en infiltration av det potentiellt maximala destillatet, som är möjligt att framställa med tillgänglig energi, skulle uttagen från de befintliga grundvattentäkterna kunna ökas med 200-230 % utan att influensområdet för grundvattennivåer förändras nämnvärt, förutsatt att fler uttagsbrunnar installeras.

  • 23.
    Barlaz, Morton
    et al.
    North Carolina State University.
    Lagerkvist, AndersLuleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.Matsuto, ToshihikoHokkaido University.
    Proceedings from the 3rd Intercontinental Landfill Research Symposium: Toya Lake, Japan, November 29 - December 2, 2004. ICLRS proceedings2004Collection (editor) (Other academic)
  • 24.
    Belo Fernandes, Ivan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Geometallurgical approach to understand how the variability in mineralogy at Zinkgruvan orebodies affects the need for copper activation in the bulk rougher-scavenger flotation2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Zinkgruvan is a Pb-Zn-Ag deposit located in south-central Sweden, owned and operated by Lundin Mining. The ore is beneficiated by a collective-selective flotation circuit, recovering both galena and sphalerite in a bulk rougher-scavenger flotation stage and later on separating them into two final products. Opportunities for increase in zinc recovery in the bulk rougher scavenger flotation stage have been identified as the plant is relying on natural Pb-activation to process the ore.

    Process mineralogical tools were used to characterize four different orebodies from Zinkgruvan (Burkland, Borta Bakom, Nygruvan and Sävsjön) and evaluate the metallurgical performance for flotation and magnetic separation, following a geometallurgical approach to better understand and predict the behavior of such ore types in processing plant.

    The first hypothesis in this thesis is that by addition of copper sulfate and increased collector dosage, Zn recovery will be improved without being detrimental to galena flotation. Results demonstrated that there is a significant increase in Zn recovery by further increasing collector dosage and copper-activating the flotation pulp in the scavenger stage. For instance, an increase in zinc recovery up to 16% has been achieved after addition of copper sulfate. Galena is readily floatable while sphalerite takes longer to be recovered. In addition, iron sulfides take longer to be recovered and, after addition of copper sulfate, there was an increase in iron sulfide recovery.

    The amount of iron sulfides reporting to the concentrate should still not be a problem to the plant. Most of the Fe in the concentrate is still coming from the sphalerite lattice. However, it might be that some orebodies coming into production in the near future have higher amounts of pyrrhotite, which might be a problem. Therefore, magnetic separation methods have been tested to remove pyrrhotite from the bulk ore. The second hypothesis is that the high Fe content in the concentrate might be due to the presence of iron sulfides, in which case they could be selectively removed by magnetic separation.

    XRD analyses demonstrated that Sävsjön is a highly variable orebody, and that its high Fe content varies with the location inside the orebody, being caused by either iron sulfide or iron oxide minerals. Both monoclinic and hexagonal pyrrhotite have been observed. Davis Tube could remove monoclinic pyrrhotite but it was very inefficient when dealing with hexagonal pyrrhotite. WHIMS, on the other hand, performed well for both types of pyrrhotite. When applying Davis Tube on Sävsjön OLD feed, a concentrate with up to 52.3% pyrrhotite is achieved, at a recovery of 35.32%. However, sphalerite is also reporting to the magnetic concentrate, which would generate Zn losses for the overall process. Zinc losses were up to 15.3% when the highest field strength was applied. Therefore, the applicability of magnetic separation for Zinkgruvan ore must be further evaluated.

  • 25.
    Bergkvist, Adam
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Mobil bergkrossning: Energibehov och emissioner2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I detta examensarbete undersöks energibehov och emissioner hos mobila krossanläggningar tillhörande NCC Industry AB. Bergtäkterna Eker och Dylta i Örebro län samt Mörtsjön i Södermanlands län har studerats och analyserats. Dessa bergtäkter producerar ballastprodukter som till större del används i anläggningsindustrin och vid asfaltstillverkning. Tester har genomförts på den elektriska konsumtionen i de olika anläggningarna för att beräkna relevanta parametrar som varit eftersökta. Produktionsrapporter och elmätningar har sammanställts, löpande under ett flertal veckor, i ett räknedokument för att kunna erhålla efterfrågade datavärden.

    De sökta faktorerna har varit energibehov i form av kWh/Ton samt emissioner i form av kg CO2/Ton. Mätningarna avser krossar, siktar och transportband vid maskinuppställningar för mobil krossning. Resultaten visar att värden på elförbrukningen uppgår till 2,1 kWh/ton med en variation från 1,1 till 3,1 kWh/ton beroende på ingående maskiner och driftförhållanden. För CO2-emissionerna var motsvarande genomsnitt 0,9 kg CO2/ton vid dieseldrift med variation 0,4 till 1,6 kg CO2/ton. Vid omräkning till en tänkt nätdrift med el låg genomsnittet på 0,17 kg CO2/ton. Beräkningarna skall bidra till en grönare tillverkningsprocess av ballastprodukter och kom att visa att skillnaderna i utsläpp (kg CO2/Ton) är uppemot 90 % större vid dieseldrift gentemot eldrift på en av de olika anläggningarna. Dessa resultat har sedan analyserats och rekommendationer görs för framtida drift och investeringar i samtliga anläggningar. Dessa rekommendationer utvärderas sedan av NCC för att avgöra huruvida de är relevanta eller icke. Att genomföra ombyggnationer och modifiera utrustningen kan dock vara mycket kostsamt. Elektricitetsproduktionen är inte analyserad i rapporten. Beräkningar är utförda med förutsättningen att elen är av nordisk mix. Dessa uppgifter är inhämtade från Naturvårdsverket. En ekonomisk analys av denna investering ingår inte i denna rapport. 

  • 26.
    Bergman, Anders
    Luleå tekniska universitet.
    Characterisation of industrial wastes1996Licentiate thesis, monograph (Other academic)
  • 27.
    Bergman, Anders
    et al.
    Luleå University of Technology.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Carbonate precipitation in alkaline wastes1996In: 12th International conference on solid waste technology and management, 1996Conference paper (Refereed)
    Abstract [en]

    Carbonate precipitation is known to occur in landfilled ashes and is often reported as a problem because of the precipitates tendency to clog drains and other leachate transport facilities. The Up-take of carbon dioxide by alkaline wastes and leachates will influence their properties e.g.; The hydraulic and gas conductivity of solid wastes will decrease as carbonates precipitate in the pores of the waste. The pH will change towards neutral values as carbonates form changing the mobility of metals and other elements A neutral pH will also allow biological reactions to act on the waste, especially if the waste contain organic material as e.g. ashes often do. Adding carbon dioxide to wastes can thus be a cheap and powerful treatment, yielding a less hazardous waste.

  • 28.
    Bergman, Hans
    Luleå tekniska universitet.
    Metanoxidation i täckskikt på avfallsupplag1995Licentiate thesis, monograph (Other academic)
  • 29.
    Bergquist, Bjarne
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Garvare, Rickard
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Eriksson, Henrik
    Chalmers University of Technology.
    Hallencreutz, Jacob
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Langstrand, Jostein
    Linköpings universitet.
    Vanhatalo, Erik
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Zobel, Thomas
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Alive and kicking – but will Quality Management be around tomorrow?: A Swedish academia perspective2012In: Quality Innovation Prosperity, ISSN 1335-1745, E-ISSN 1338-984X, Vol. 16, no 2, p. 1-18Article in journal (Refereed)
    Abstract [en]

    The purpose of this article is to describe how Quality Management (QM) is perceived today by scholars at three Swedish universities, and into what QM is expected to develop into in twenty years. Data were collected through structured workshops using affinity diagrams with scholars teaching and performing research in the QM field. The results show that QM currently is perceived as consisting of a set of core of principles, methods and tools. The future outlook includes three possible development directions for QM are seen: [1] searching for a “discipline X” where QM can contribute while keeping its toolbox, [2] focus on a core based on the traditional quality technology toolbox with methods and tools, and [3] a risk that QM, as it is today, may seize to exist and be diffused into other disciplines.

  • 30.
    Bergquist, Bjarne
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Garvare, Rickard
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Eriksson, Henrik
    Chalmers tekniska högskola, Teknikens ekonomi och organisation.
    Hallencreutz, Jacob
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Langstrand, Jostein
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Avdelningen för Kvalitetsteknik.
    Vanhatalo, Erik
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Zobel, Thomas
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Alive and kicking–but will Quality Management be around tomorrow?: A Swedish academia perspective2012Conference paper (Refereed)
    Abstract [en]

    Purpose: There is a lack of a recognized conception of quality management (QM) comprises of, as well as a clear roadmap of where QM is heading. The purpose of this article is to investigate how QM is perceived today by scholars at three Swedish universities, but also how and into what QM is expected to develop into in twenty years.Methodology: Data have been collected through three structured workshops using affinity diagrams with scholars teaching and performing research in the QM field affiliated with three different Swedish universities.Findings: The results indicate that current QM is perceived similarly among the universities today, although the taxonomy differs slightly. QM is described as a fairly wide discipline consisting of a set of core of principles that in turn guide which methods and tools that currently by many are perceived as the core of the discipline. The outlook for the future differs more where three possible development directions for QM are seen: [1] searching for a “discipline X” where QM can contribute while keeping its toolbox, [2] focus on a core based on the traditional quality technology toolbox with methods and tools, and [3] a risk that QM, as it is today, may seize to exist and be diffused into other disciplines. Originality/value: This article contributes with a viewpoint on QM today and its future development from the academicians’ perspective.

  • 31.
    Bert, Valérie
    et al.
    INERIS, Clean and Sustainable Technologies and Processes Unit, DRC/RISK, Parc Technologique Alata.
    Neu, S.
    Technische Universität Dresden, Institute of Wood and Plant Chemistry.
    Zdanevitch, Isabelle
    NERIS, Clean and Sustainable Technologies and Processes Unit, DRC/RISK, Parc Technologique Alata.
    Friesl-Hanl, Wolfgang
    AIT Austrian Institute of Technology GmbH, Energy Department.
    Collet, Serge
    INERIS, Sources and Emissions Unit, DRC/CARA, Parc Technologique Alata.
    Gaucher, Rodolphe
    INERIS, Clean and Sustainable Technologies and Processes Unit, DRC/RISK, Parc Technologique Alata.
    Puschenreiter, Markus
    University of Natural Resources and Life Sciences Vienna – BOKU, Department of Forest and Soil Sciences.
    Müller, Ingo
    Saxon State Agency for Environment, Agriculture and Geology.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    How to manage plant biomass originated from phytotechnologies?: Gathering perceptions from end-users2017In: International journal of phytoremediation, ISSN 1522-6514, E-ISSN 1549-7879, Vol. 19, no 10, p. 947-954Article in journal (Refereed)
    Abstract [en]

    A questionnaire survey was carried out in 4 European countries to gather end-user's perceptions of using plants from phytotechnologies in combustion and anaerobic digestion (AD). 9 actors of the wood energy sector from France, Germany and Sweden, and 11 AD platform operators from France, Germany and Austria were interviewed. Questions related to installation, input materials, performed analyses, phytostabilization and phytoextraction. Although the majority of respondents did not know phytotechnologies, results suggested that plant biomass from phytomanaged areas could be used in AD and combustion, under certain conditions. As a potential advantage, these plants would not compete with plants grown on agricultural lands, contaminated lands being not suitable for agriculture production. Main limitations would be related to additional controls in process' inputs and end-products and installations that might generate additional costs. In most cases, price of phytotechnologies biomass was mentioned as a driver to potentially use plants from metal-contaminated soils. Plants used in phytostabilisation or phytoexclusion were thought to be less risky and, consequently, benefited from a better theoretical acceptance than those issued from phytoextraction. Results were discussed according to national regulations. One issue related to the regulatory gap concerning the status of the plant biomass produced on contaminated land.

  • 32.
    Bertholdsson, Morgan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Utredning om dimension av kamjärnsbultar i Garpenbergsgruvan2018Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
  • 33.
    Bertilsson, Olle
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Study of leaching behavior of tin in Zinc-clinker and Mixed Oxide2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Due to the increasing usage of Sn in different electronics, such as solders and in touchscreens, together with Boliden Rönnskärs increased intake of electronic waste as a secondaryraw material, a Zn-containing product called Zn-clinker has increasing amounts of Sn. TheZn-clinker is shipped to Boliden Zn-smelter in Odda, where the Zn-clinker is mixed in withcalcine (roasted concentrate) and leached in several steps. Since Zn-clinker is a product froma halogen removal in a clinker-furnace, the feed material (Mixed Oxide), for this furnace, wasalso investigated since there are plans to replace clinkering with soda-washing in the future.Most of the Sn ends up in the leaching residue which then is deposited in the mountaincaverns close by the Boliden Odda smelter. Boliden is studying the possibility to recoverPb/Ag and Sn content from the leaching residue and create a valuable by-product. Bystudying how the leaching of Sn behaves, together with a characterization of the materials, thefollowing question should be answered: “During which sulphuric acid leaching conditions, ofZn-clinker and Mixed Oxide, is the leaching of Sn minimized?”

    The leaching results for Zn-clinker showed that 8-10% Sn will leach out, despite changingtemperature, redox potential, time and pH. A characterization of the material with SEM-EDSand XRD-analysis was also conducted to see if Sn could be identified in any phases in thematerials. The studies provided enough evidence that Zn2SnO4 could be concluded to be themain phase in the leaching residue for Zn-clinker, a form that would not leach underconditions presented in this project. However, 8-10% of the Sn will come together with Feand when Fe leach out, so does Sn.

    The leaching results for Mixed Oxide pointed towards that different phases from them foundin Zn-clinker was present. Sn losses varied between 10-20% but raised to 47% whentemperature was changed to 80 °C during leaching. The SEM-EDS analysis showed that theidentified Sn-phases contained more Sn than in Zn-clinker and together with the leachingresults, a conclusion that Sn would mainly be found as SnO2 or SnO in the Mixed Oxide, butthere is still uncertainty about the distributions of these forms.

    Unfortunately half of the As leached out during the soda-washing for Mixed Oxide, creating aleachate with Cl, F and As that need to be taken care of. This could be challenging andpresenting a costly side-project for the route different from the Zn-clinker route used today.Another observation was that PbCO3 formed during the soda-washing, a phase that willconsume more sulphuric acid during leaching.

  • 34.
    Beylich, Achim A.
    et al.
    Department of Earth Sciences, Uppsala University.
    Molau, Ulf
    Botanical Institute, Plant Ecology, Gothenburg University.
    Luthbom, Karin
    Luleå tekniska universitet.
    Gintz, Dorothea
    Institute for Geological Sciences, Hydrogeology, Free University of Berlin.
    Rates of chemical and mechanical fluvial denudation in an arctic oceanic periglacial environment, Latnjavagge drainage basin, northernmost Swedish Lapland2005In: Arctic, Antarctic and Alpine research, ISSN 1523-0430, E-ISSN 1938-4246, Vol. 37, no 1, p. 75-87Article in journal (Refereed)
    Abstract [en]

    A process geomorphological investigation was started in 1999 to study present denudation rates and the mutual relationship of chemical and mechanical fluvial denudation in periglacial environments. Latnjavagge (9 km2; 950-1440 m a.s.l.; 68°20'N, 18°30'E) was chosen as a representative drainage basin of the arctic-oceanic mountain area in northernmost Swedish Lapland. Atmospheric solute inputs, chemical denudation, and mechanical fluvial denudation were analyzed. During the arctic summer field seasons of 2000, 2001, and 2002 measurements of daily precipitation, solute concentrations in precipitation, and in melted snow cores, taken before snowmelt, were recorded. In addition, solute and suspended sediment concentrations in creeks were analyzed, and bedload tracer movements were registered during the entire summer seasons (end of May until beginning of September). Results show a mean annual chemical denudation net rate of 5.4 t km-2 yr-1 in the entire catchment. Chemical denudation in Latnjavagge is less than one third of chemical denudation rates reported for Kärkevagge (Swedish Lapland) but seems to be at a similar level as in a number of other subarctic, arctic, and alpine environments. Mechanical fluvial denudation is lower than chemical denudation. Most sediment transport in channels occurs in the early summer season during a few days with snowmelt generated runoff peaks. The main sediment sources in the drainage basin are mobilized channel bed pavements exposing fines, ice patches/fields, and material mobilized by slush flows. The calculated mean mechanical fluvial denudation rate is 2.3 t km-2 yr-1 at the inlet of lake Latnjajaure, situated in Latnjavagge close to the outlet of the valley. A very stable vegetation cover and rhyzosphere in this environment mainly explain the low value. The mean mechanical fluvial denudation rate at the outlet of the entire Latnjavagge drainage basin, below lake Latnjajaure, is only 0.8 t km-2 yr-1. Both chemical and mechanical fluvial denudation show low intensity. The results from Latnjavagge support the contention that chemical denudation is a somewhat important denudational process in periglacial environments.

  • 35.
    Bhattacharya, Prosun
    et al.
    KTH-International Groundwater Arsenic Research Group, Department of Sustainable Development, Environmental Sciences and Engineering, KTH Royal Institute of Technology.
    Vahter, Marie E.
    Institute of Environmental Medicine, Karolinska Institutet.
    Jaresjö, Jerker
    Department of Physical Geography and Quaternary Geology, Stockholm University.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ahmad, Arslan
    KWR Watercycle Research Institute, Nieuwegein.
    Sparrenbom, Charlotta Jönsson
    Department Geology, Quaternary Sciences, Lund University.
    Jacks, Gunnar
    KTH-International Groundwater Arsenic Research Group, Department of Sustainable Development, Environmental Sciences and Engineering, KTH Royal Institute of Technology.
    Donselaar, Marinus Eric
    Department of Geoscience and Engineering, Delft Univ. of Technology.
    Bundschuh, Jochen
    KTH-International Groundwater Arsenic Research Group, Department of Sustainable Development, Environmental Sciences and Engineering, KTH Royal Institute of Technology.
    Naidu, Ravi
    Global Centre for Environmental Remediation (GCER), Faculty of Science & Information Technology, The University of Newcastle.
    Editors’ foreword2016In: Arsenic Research and Global Sustainability: Proceedings of the 6th International Congress on Arsenic in the Environment, AS 2016 / [ed] Bhattacharya, Prosun; Vahter, Marie; Jarsjo, Jerker; Kumpiene, Jurate; Charlotte, Sparrenbom, London: CRC Press, 2016, p. xlv-xlviConference paper (Refereed)
  • 36.
    Bjurström, Henrik
    et al.
    ÅF-Industry AB.
    Lind, B.B.
    Swedish Geotechnical Institute.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Unburned carbon in combustion residues from solid biofuels2014In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 117, no Part A, p. 890-899Article in journal (Refereed)
    Abstract [en]

    Unburned carbon (UC) in 21 combustion residues from solid biofuels has been examined using several methods of analysis (including LOI and TOC) as well as micro-Raman spectroscopy. The concentration of unburned carbon in the residues varied over an order of magnitude and in several samples accounted for about 10% of the ash mass. It was observed that TOC had a poor correlation to organic carbon, especially for fly ashes. LOI at all tested temperatures showed a better correlation than TOC to the organic carbon content, whereas the TOC is better correlated to elemental carbon. LOI550 gave a larger variation and a less complete mobilisation of unburned carbon than LOI at 750 or 975 °C did, but at the highest temperature metal oxidation was notably affecting the mass balance to the extent that some samples gained mass. For this reason, and of the temperatures tested, LOI750 seem to be the most stable indicator for organic remains in the incineration residuals. Most of the unburned carbon is elemental, and only slowly degradable, so the potential emissions of organic compounds from ashes should not be assessed by using a TOC test. The structure of the detected elemental carbon in UC is similar to that of activated carbon, which indicates a potentially large specific surface. This should be borne in mind when assessing the environmental impact of using ash for different purposes, including use as a construction material. Field studies are needed to verify the actual impact as it may depend on environmental conditions.

  • 37.
    Björnström, Albert
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Flödeskalibrering: Analys av kalibreringsprocesser2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In December 2015 the Paris Agreement was signed in order to create a better global climate. According to the agreement, all countries 'emissions shall be reported to the UN. To be able to do this current emission levels must be known, which means measurement and calculation of emissions are necessary.

     

    The state-owned mining company Luossavaara Kiirunavaara AB (LKAB) operates iron ore mines in Northen Sweden. The iron ore products produced at the KK4 coal mill in Kiruna, consists of some additives that form carbon dioxide when burned. The amount of additives burned is measured using two flowmeters. To ensure that these meters have approved accuracy, annual calibrations are performed where measured volume is compared to a reference volume. In order to ensure that LKAB's calibration method works, another type of calibration was performed by an external company. The results between the two calibration methods differ significantly, which led to this report.

     

    The purpose of this work is to develop improvement proposals for LKAB's calibration method and to present suggestions on how LKAB can create better conditions for the other so called transit time calibration method. By analyzing each method and performing measurements, tests and calculations, weaknesses are noted. Tests show that a weakness of LKAB's calibration is that the level measurement method used is person-dependent. Level measurement with laser range gauge is tested with good results, why this type of measurement is recommended in the future. The main weakness with transit time method is primarily that it is sensitive to variation of the inner diameter of the pipe. In order for this method to provide reliable results, rebuilding of pipes and carefully measured internal diameter are required. Accurate flow measurement means that current carbon dioxide emissions can be calculated, which enables continued work towards set environmental goals. Flowmeters also have a significant role in product quality in KK4, which means that this report can contribute to higher quality and economic profitability.

  • 38.
    Bogner, Jean E.
    et al.
    Argonne National Laboratory, Argonne, IL.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Early diagenesis of garbage: landfills as engineered anoxic basins1996In: Geological Society of America, 28th annual meeting, Denver, CO, United States, Oct. 28-31, 1996, Geological Society of America, 1996, p. 257-Conference paper (Other academic)
    Abstract [en]

    Early diagenesis of buried organic carbon in anoxic basins is dominated by microbial decomposition processes at temperatures and pressure slightly above ambient. Such conditions also describe decomposition of refuse in sanitary landfills and provide a reasonable model for systematic studies of their long-term geochemistry. For shorter time frame (decades), controlled high-solids anaerobic digestion systems provide a second model for investigation of optimized landfill systems. In this paper, we introduce both models through a series of preliminary mass-balances to develop a realistic overview of landfill processes, especially emphasizing carbon cycling in field settings over various time-frames. The terminal product of short-term anaerobic decomposition is methane--produced by methanogenic bacteria from some fraction of organic carbon landfilled. Laboratory studies of optimized landfill systems (ours and from the literature) indicate that, at best, 25-45% of organic carbon is converted to biogas carbon (methane and carbon dioxide); such percentages are rarely attained in field settings. Most of the methane is produced from cellulosic substrates while lignin substrates are recalcitrant, with lignin carbon entering sedimentary storage for time frames longer than the four decades of widespread landfilling experience in the U.S. and western Europe. Over time frames in excess of centuries, further transformations via kerogen pathways are possible but highly speculative. Certainly, exhumation of old refuse at archeologic sites indicates that organic carbon preservation can be documented for at least one or two millenia. From controlled incubation of unamended field samples and from field studies of net methane emissions, it is clear that rates of methane production and consumption both vary of several orders of magnitude in field settings; their dynamic are rapid and complex spatially and temporally. Unraveling these dynamics is necessary to suggest the overall relevance of these engineered anoxic basins to issues of atmospheric methane increases and terrestrial carbon storage.

  • 39.
    Bolan, Nanthi
    et al.
    Centre for Environmental Risk Assessment and Remediation, University of South Australia.
    Kunhikrishnanc, Anitha
    Chemical Safety Division, Department of Agro-Food Safety, National Academy of Agricultural Science.
    Thangarajan, Ramya
    Centre for Environmental Risk Assessment and Remediation, University of South Australia.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Park, Jinhee
    Centre for Mined Land Rehabilitation, University of Queensland.
    Makino, Tomoyuki
    Soil Environmental Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba.
    Kirkham, Mary Beth
    Department of Agronomy, 2004 Throckmorton Plant Sciences Center, Kansas State University.
    Scheckel, Kirk
    National Risk Management Research Laboratory, U.S. Environmental Protection Agency, 5995 Center Hill Avenue, Cincinnati.
    Remediation of heavy metal(loid)s contaminated soils: To mobilize or to immobilize?2014In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 266, p. 141-166Article in journal (Refereed)
    Abstract [en]

    nlike organic contaminants, metal(loid)s do not undergo microbial or chemical degradation and persist for a long time after their introduction. Bioavailability of metal(loid)s plays a vital role in the remediation of contaminated soils. In this review, the remediation of heavy metal(loid) contaminated soils through manipulating their bioavailability using a range of soil amendments will be presented. Mobilizing amendments such as chelating and desorbing agents increase the bioavailability and mobility of metal(loid)s. Immobilizing amendments such of precipitating agents and sorbent materials decrease the bioavailabilty and mobility of metal(loid)s. Mobilizing agents can be used to enhance the removal of heavy metal(loid)s though plant uptake and soil washing. Immobilizing agents can be used to reduce the transfer to metal(loid)s to food chain via plant uptake and leaching to groundwater. One of the major limitations of mobilizing technique is susceptibility to leaching of the mobilized heavy metal(loid)s in the absence of active plant uptake. Similarly, in the case of the immobilization technique the long-term stability of the immobilized heavy metal(loid)s needs to be monitored.

  • 40.
    Brundin, Herman
    et al.
    SÖRAB.
    Kihl, Anders
    Rang-Sells Avfallsbehandling AB.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Pusch, Roland
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Rihm, Thomas
    RVF service AB.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Tham, Gustav
    Telge Återvinning AB.
    Långtidsegenskaper hos tätskikt innehållande bentonit2001Report (Other academic)
    Abstract [sv]

    Bentonit är en starkt vattenupptagande och svällande naturlig lera med låg vattengenomsläpplighet. Huvudkomponenten är mineralet montmorillonit, som tillhör gruppen smektiter och som ger bentoniten dess unika egenskaper. Syftet med uppdraget är att söka identifiera vilka mekanismer och faktorer som kan vara begränsande för funktionen på kort och lång sikt hos tätskikt innehållande bentonitmattor samt blandningar av bentonit och andra material. I rapporten ges underlag för projektering, utformning och drift av deponier med tätskikt innehållande bentonit. Där redovisas också tre fallstudier från Högbytorp, Löt och Tveta.

  • 41.
    Brännvall, Evelina
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Accelerate ageing of refuse-derived-fuel (RDF) fly ashes2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Ashes have properties that can be exploited in various applications, e.g. some ashes can be used in the construction of barriers in a landfill final top cover. A landfill top cover is a multilayer construction that protects the environment in several ways, for instance hindering gas emissions from the landfill body and water infiltration into the waste.Impervious natural materials like clay, synthetic materials like geomembranes or bentonite carpets, geosynthetic clay liners or combinations of such materials are commonly used in landfill top cover constructions. Since differential settlement may occur and the lifetimes of the synthetic materials are uncertain, it is advantageous to use thick mineral constructions. There is a great need for these materials, and substantial savings of resources can be made if alternative waste materials, like ashes, are used. Currently, ashes are either landfilled or used as construction materials. They are subject to weathering processes, including physical, chemical and mineralogical changes caused (inter alia) by fluctuations of temperature and humidity, atmospheric gases or acid rain. Ashes contain various potentially hazardous and non-hazardous chemical compounds. Therefore, precautions must be taken to avoid leaching of substances such as heavy metals into the surrounding environment. Mineral phases that are initially present and/or that form during the ageing are primarily responsible for the immobilization or leaching of diverse metals and salts. Newly formed mineral phases like clay minerals are of main interest, because of their very high cation exchange capacity, swelling and expansion properties.The conditions found in a landfill environment are likely to favour clay mineral formation. This thesis is based on studies on the effects of accelerated ageing on refuse-derived-fuel (RDF) fly ashes, in experiments under controlled laboratory conditions, intended to derive models to predict the stability of RDF fly ashes used in a landfill liner and the mineralogical changes that occur in them. A reduced factorial design was applied, followed by multivariate data analysis, to evaluate the effects of five factors - carbon dioxide (CO2) levels, temperature, relative air humidity (RH), time and the quality of added water - on mineral transformations within the ashes, and their acid neutralization capacity (ANC) and leaching behaviour.Minerals (ettringite and hydrocalumite) promoting the immobilization of hazardous compounds were found in both fresh ash and ash aged under atmospheric conditions, but these minerals disappeared upon carbonation. The main phases in ash at 20% and 100% CO2 were calcite, gypsum/anhydrite and vaterite. The abundance of gypsum and anhydrite was directly related to the temperature at which ashes were aged. The major mineral phases detected in ashes aged under 20% CO2, 65% RH and 30°C (corresponding to conditions generally found in a landfill cover) were calcite and gypsum/bassanite. The pH values of these ash specimens ranged from 7.2 to 7.6, indicating advanced carbonation. Ageing decreased pH values from 12.4 to 7.2, consequently affecting the leaching behaviour of most chemicals measured in the leachates. Levels of Ba, Ca, Cl, Cr, Cu, Pb, K and Na decreased over the study period while those of Mg, Zn and SO4 increased. No clay minerals were detected by XRD and SEM analysis in either fresh or aged ashes. However, geochemical modelling indicated that such minerals may precipitate. The modelling also indicated that clay minerals like saponite, vermiculite, chrysotile and hydrotalcite were likely to precipitate in most leachates from ash aged for 3, 10 and 22 months. Smectite, montmorillonite and illite may precipitate in leachates of ash aged for 31 months. The formation of smectite, montmorillonite and vermiculite would be advantageous due to their very high cation exchange capacities, which would favour the stabilization/immobilization of heavy metals in the mineral phases.

  • 42.
    Brännvall, Evelina
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Suitability of fly ash for construction and land applications2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Municipal solid waste incineration fly ash is often landfilled or sent abroad for stabilization because it is considered a hazardous waste. These approaches to fly ash are both costly, and highlight the need for alternative and sustainable ash recycling. Both the needs of waste recycling and preservation of natural resources can be solved by using fly ashes as a secondary construction material and as soil fertilizer.Three types of fly ashes have been investigated in the laboratory experiments. Namely municipal solid waste incineration (MSWI), refuse-derived-fuel (RDF) and biofuel fly ashes. Factors influencing changes in chemical properties and mineralogical composition of RDF fly ash exposed to environmental conditions close to those that are found in a landfill top cover were evaluated in the accelerated ageing experiment. Element availability to leaching and plant uptake in soil amended with MSWI, biofuel fly ashes and biosolids was also evaluated.RDF fly ash exposed to the conditions found in a landfill top cover (20% CO2, 65% RH, 30°C T) lead to the chemical and mineralogical transformations that resulted in reduced leaching of most of the elements studied here. Only concentrations of Cl- in the leachates were an issue, because they still exceeded the leaching limit values; nevertheless the leaching of this element in aged ash decreased by 50% compared to fresh ash.Application of pelletized MSWI fly ash with biosolids on soil resulted in elevated total concentrations of As, Cd and Pb in soil (by 29%, 100% and 300%), but dissolved concentrations of these elements in soil pore water, except the As, were low as in the range of drinking water concentrations (98/83/EC). Furthermore, the concentrations of Cd and Pb in plant biomass were negligible regardless of the type of ash used.Based on the observations, RDF fly ash is considered as a suitable material to be used in a landfill liner. Whereas MSWI and biofuel fly ashes based on element availability for plants studies, could be considered suitable for land applications. But doses to be applied on soil should be adjusted to the type of ashes used to avoid accumulation of potentially toxic elements in soil over time.

  • 43. Brännvall, Evelina
    et al.
    Andreas, Lale
    Diener, Silvia
    Tham, Gustav
    Telge AB, Södertälje.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Influence of accelerated ageing on acid neutralization capacity and mineralogical transformations in refuse derived-fuel fly ashes2009In: SARDINIA 2009: Twelfth International Waste Management and Landfill Symposium ; [5 - 9 October 2009, S. Margherita di Pula, Cagliari, Sardinia, Italy] / [ed] Raffaello Cossu, Cagliari: CISA, Environmental Sanitary Engineering Centre , 2009, Vol. 1Conference paper (Refereed)
    Abstract [en]

    This study is a part of a long-term collaboration between Telge Återvinning AB at Södertälje in South Sweden and Lulea University of Technology (LTU) in the Northern part of Sweden. Ashes and other industrial wastes used for landfill cover construction have been studied for several years. However, there is a need for further investigations with regard to the long-term mechanical and chemical stability of ash liners in landfill cover constructions. Long-term changes of ashes are investigated by laboratory studies on accelerated weathering (ageing) using experimental design. With regard to weathering, several stages can be identified: hydration and carbonation are well known processes while the processes surrounding the conversion of ash to clay minerals are less well known. There are a number of studies showing that the process of mineral transformation during the ageing of coal or MSWI ashes is quite similar to that of volcanic ashes in nature. Yet, the time frames are quite different: while volcanic ashes need several thousands of years for clay mineral development, there are evidences as well that e.g. clay illite is formed from glass phases in MSWI bottom ash after only 12 y or that clay like amorphous material can be formed in micro-scale throughout the surfaces of coal ash particles after 8 y of natural weathering (Zevenbergen et al., 1999; Zevenbergen et al., 1998). There are a lot of studies performed on rapid fly ash conversion into zeolites by hydrothermal alkaline treatment, the success of which strongly depends on alkaline conditions and the silica-alumina composition of the fly ash source (Inada et al., 2005). These results provide further support to the hypothesis that the observed rapid clay like mineral formation arose as a result of the initially high pH of ash, which promotes rapid dissolution of certain components of aluminosilicate glasses. Furthermore, in a long term perspective these aluminosilicates can transform into zeolites, smectites or halloysites dependent on the solution pH and leaching rate. Based on these studies on volcanic, coal or MSWI ashes we presume that refuse derived fuel (RDF) ashes, like those that are used in the Tveta landfill cover, will be subject to analogical weathering and mineral transformation processes.In order to investigate the mineral transformation in RDF fly ashes, a designed laboratory experiment was performed. A reduced factorial experimental design for accelerated ageing has been applied to evaluate the influence of five factors: carbon dioxide (CO2), temperature, relative air humidity, time and, quality of added water (Table 1). Table 1 Factors and levels tested in the reduced multivariate factorial design for the study of accelerated ageing of RFD fly ashesFactorLowMiddleHighCarbon dioxide, CO2 (%)Atmosphere (0.038)20*100Temperature, ºC5 3060Relative air humidity, Rh (%)3065100Time, months31022Water qualityDistilled -LeachateThe influence of these factors on mineralogical composition, leaching behaviour and acid neutralization capacity (ANC) is analysed and evaluated with the aid of multivariate data analysis. The MVDA modelling was performed with SIMCA-P+ 11.5 version program developed by Umetrics AB (Eriksson and Umetrics Academy, 2006). Principle component analysis (PCA) technique was used and presented in this paper. PCA is an interdependence model where all variables are analysed simultaneously as a single set in a data matrix X. Triplicates were tested for each factor combination. Sampling was performed after 3, 10 and 22 months of accelerated ageing. Mineral composition was analysed by X-Ray Diffraction (XRD). Acid neutralisation capacity was performed at 8.3 and 4.5 pH with 0.1 M HCl solution. The experimental set-up of accelerated ageing of RDF fly ashes is showed in Fig. 1. Preliminary evaluation of the mineral transformations in aged RDF fly ashes revealed that the carbonation process was not yet completed in the some of the specimens (Fig.2). This still caused high pH (pH=12.7) in the solution even though a calcite phase was found in all aged fly ashes. Multivariate data analysis confirmed that carbon dioxide affects the pH and ANC of fly ashes during ageing of RDF fly ashes. The specimens prepared with leachate water had higher ANC than the specimens with distilled water. The ANC8.3 was most influenced by 30 ºC temperature and 65 % relative humidity (ANC8.3 = 0.05 mmol/g) and this well corresponds to the results found in the literature. The ageing time factor has the highest influence on ANC4.5. A more detailed analysis of other mineral phases including clay-like minerals in aged fly ashes will be performed later.The results of this study will contribute to the better understanding of ash formation processes and improved possibilities to make beneficial use of ashes as an alternative to landfilling.Figure 1. Experimental set-up for investigations of the long-term behaviour of the ashes under different environmental conditions. Figure 2. XRD patterns of RDF fly ashes at different ageing conditions. a) N33, b) N71, c) N15, d) N85, and e) N51. The peaks are labelled A (anhydrite), C (calcite), E (ettringite), F (Friedel's Salt), Ge (gehlenite), H (halite), He (hematite), P (portlandite), Q (quartz), S (sylvite), V (vaterite).

  • 44. Brännvall, Evelina
    et al.
    Andreas, Lale
    Diener, Silvia
    Tham, Gustav
    Telge AB.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Formation of secondary mineral phases during the ageing of RDF fly ashes2010In: The 6th Intercontinental Landfill Research Symposium, 2010, p. 110-112Conference paper (Other academic)
  • 45.
    Brännvall, Evelina
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Andreas, Lale
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Diener, Silvia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Factors influencing chemical and mineralogical changes in RDF fly ashes during aging2014In: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 140, no 3, article id 4013014Article in journal (Refereed)
    Abstract [en]

    The effects of aging should be considered for reliable long-term assessments of the environmental risks of the use of refuse-derived-fuel (RDF) fly ash as landfill top cover liner material. Mineral transformations that occur in RDF fly ash, and the effects of selected factors on these transformations, were studied on compacted fly ash specimens in an accelerated aging experiment using a reduced factorial design. Carbon dioxide concentration, temperature, relative air humidity, time, and the quality of added water were varied in six factor combinations. Acid neutralization capacity and leaching behavior were analyzed after four different periods of time. The results were evaluated with multivariate data analysis. A significant change in the acid neutralization capacity, a decrease in leaching of Ba, Ca, Cl − , Cr, Cu, Pb, K, and Na, and an increase in solubility of Mg, Si, Zn, and SO 2− 4 could be attributed to different aging conditions

  • 46.
    Brännvall, Evelina
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Andreas, Lale
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Changes of fly ash properties during the ageing2015In: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 141, no 5, article id 4014083Article in journal (Refereed)
    Abstract [en]

    Aging of refuse-derived fuel (RDF) fly ashes was investigated in a long-term laboratory experiment. Aging affected the chemical stability of RDF fly ash in terms of leaching behavior, ANC, and mineralogical transformations. The design of experiment model evaluation showed that the use of RDF ashes in a top cover liner construction has the following advantages: most of the investigated hazardous elements like Pb, Cl, Cr, Cu, etc., will not be released from the ashes, and their buffer capacity will increase with time. However, aging has the disadvantage that leaching of Zn and SO 4 is likely to increase. The multivariate data analysis of the coefficients of variation did not reveal any systematic errors in the performance of the experiment. However, batch leaching test not always reflect the real situation in the landfill top cover environment.

  • 47.
    Brännvall, Evelina
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Andreas, Lale
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Travar, Igor
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ageing of ashes in a landfill top cover2011In: SARDINIA 2011: Thirteenth International Waste Management and Landfill Symposium, S. Margherita di Pula, Cagliari, Italy; 3 - 7 October 2011 / [ed] Raffaello Cossu, Cagliari: CISA Publisher, Italy , 2011Conference paper (Refereed)
    Abstract [en]

    This paper is based on studies on the effects of accelerated ageing on refuse-derived-fuel (RDF) fly ashes, in experiments under controlled laboratory conditions, intended to derive models to predict the stability of RDF fly ashes used in a landfill liner and the mineralogi-cal changes that occur in them. A reduced factorial design was applied, followed by multivariate data analysis, to evaluate the effects of five factors — carbon dioxide (CO2) levels, temperature, relative air humidity (RH), time and the quality of added water — on mineral transformations within the ashes, and leaching behaviour. The pH values of these ash specimens ranged from 7.2 to 7.6, indicating advanced carbonation. Ageing decreased pH values from 12.4 to 7.2, conse-quently affecting the leaching behaviour of most chemicals measured in the leachates. Levels of Ba, Ca, Cl, Cr, Cu, Pb, K and Na decreased over the study period while those of Mg, Zn and SO4 increased. Clay minerals could not be detected neither in fresh nor in aged ashes. However, geo-chemical modelling indicated that such minerals may precipitate.

  • 48.
    Brännvall, Evelina
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Belmonte, Carles
    Luleå University of Technology.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Characterisation of waste material mixtures for landfill top cover application2012In: Abstract proceedings of 7th Intercontinental Landfill Research Symposium: Södra Sunderbyn, June 25th to 27th, 2012 / [ed] Anders Lagerkvist, Luleå: Luleå tekniska universitet, 2012, p. 54-Conference paper (Refereed)
  • 49.
    Brännvall, Evelina
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Changes in Element Solubility in Fly Ash and Biosolid Mixtures Used for Soil Fertilization2013In: 12th International Conference on the Biogeochemistry of Trace Elements, Athens, Georgia, USA, June 16-20, 2013, 2013Conference paper (Refereed)
  • 50.
    Brännvall, Evelina
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Fly ash in landfill top covers: a review2016In: Environmental Science: Processes & Impacts, ISSN 2050-7887, E-ISSN 2050-7895, Vol. 18, no 1, p. 11-21Article in journal (Refereed)
    Abstract [en]

    Increase of energy recovery from municipal solid waste by incineration results in the increased amounts of incineration residues, such as fly ash, that have to be taken care of. Material properties should define whether fly ash is a waste or a viable resource to be used for various applications. Here, two areas of potential fly ash application are reviewed: the use of fly ash in a landfill top cover either as a liner material or as a soil amendment in vegetation layer. Fly ashes from incineration of three types of fuel are considered: refuse derived fuel (RDF), municipal solid waste incineration (MSWI) and biofuel. Based on the observations, RDF and MSWI fly ash is considered as suitable materials to be used in a landfill top cover liner. Whereas MSWI and biofuel fly ashes based on element availability for plant studies, could be considered suitable for the vegetation layer of the top cover. Responsible application of MSWI ashes is, however, warranted in order to avoid element accumulation in soil and elevation of background values over time.

1234567 1 - 50 of 633
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