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  • 1.
    Andreas, Lale
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Diener, Silvia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Hydraulic performance of a land-fill top cover based on steel slag2014Ingår i: 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 , 2014Konferensbidrag (Övrigt vetenskapligt)
    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.

  • 2.
    Andreas, Lale
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Diener, Silvia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Steel slags in a landfill top cover: Experiences from a full-scale experiment2014Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 34, nr 3, s. 692-701Artikel i tidskrift (Refereegranskat)
    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.

  • 3. Brännvall, Evelina
    et al.
    Andreas, Lale
    Diener, Silvia
    Tham, Gustav
    Telge AB, Södertälje.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Influence of accelerated ageing on acid neutralization capacity and mineralogical transformations in refuse derived-fuel fly ashes2009Ingår i: 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. 1Konferensbidrag (Refereegranskat)
    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).

  • 4. Brännvall, Evelina
    et al.
    Andreas, Lale
    Diener, Silvia
    Tham, Gustav
    Telge AB.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Formation of secondary mineral phases during the ageing of RDF fly ashes2010Ingår i: The 6th Intercontinental Landfill Research Symposium, 2010, s. 110-112Konferensbidrag (Övrigt vetenskapligt)
  • 5.
    Brännvall, Evelina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Diener, Silvia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Factors influencing chemical and mineralogical changes in RDF fly ashes during aging2014Ingår i: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 140, nr 3, artikel-id 4013014Artikel i tidskrift (Refereegranskat)
    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

  • 6.
    Diener, Silvia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ageing behaviour of steel slags in landfill liners2009Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Stålslagg är en restprodukt som kommer från ståltillverkningen. Den har kemiska och fysikaliska egenskaper som bör utnyttjas och som gör den lämplig för återanvändning, samtidigt som onödig deponering kan undvikas. Stålslagg kan återanvändas inom ståltillverkningen eller så kan den användas som konstruktionsmaterial i väg- och vattenbyggnadskonstruktioner eller i olika typer av barriärkonstruktioner som till exempel deponisluttäckningar. En deponisluttäckning består av flera skikt där tätskiktet ska ha en låg vatten- och gaspermeabilitet för att minska metan- och lakvattenutsläpp. Flera studier visar att stålslagg uppfyller dessa egenskaper och har potential att kunna användas i deponitäckning. Men det finns fortfarande oklarheter angående slaggmineralernas stabilitet över en längre tid. En deponitäcknings funktion förväntas vara stabil i många tiotals eller hundratals år. För att kunna förutsäga det långsiktiga beteendet för stålslagg i ett tätskikt genomfördes ett laboratorieexperiment vars syfte var att studera effekterna av accelererad åldring under kontrollerade förhållanden. De faktorer som studerades var koldioxidhalten, relativa luftfuktigheten, temperaturen, kontakten med lakvatten samt åldringstiden. I denna avhandling presenteras undersökningen av ljusbågsugnsslagg och skänkslagg, från framställning av höglegerat verktygsstål, efter tre respektive tio månaders accelererad åldring. Mineralogin och lakningsegenskaperna studerades genom två typer av laktester, termiska analyser, analys av syraneutraliserande kapacitet samt röntgendiffraktion. För de studerade åldringstiderna var det exponeringen av stålslaggen för en koldioxidrik atmosfär som hade den största inverkan på lakningsegenskaperna. Kalcium, aluminium, svavel och natrium var de ämnen som uppvisade den högsta utlakningen från slaggen medan metaller som krom, nickel, bly och zink endast fanns i väldigt låga koncentrationer i lakvattnet. Utlakningen av kalcium och aluminium minskade med en ökande halt av koldioxid. Termiska analyser visade på en nedbrytning av karbonater. Vikt- och entalpiförändringar mellan 100 och 1000°C utvärderades. Stålslaggens buffertkapacitet, representerad av den syraneutraliserande kapaciteten (ANC pH 4,5), reducerades inte efter tio månaders åldrande. Däremot visade uppdelningen av titreringen i två steg på en förskjutning av buffertområdena för de prover som åldrats tio månader, förmodligen på grund av karbonatbildning. Mineralogin för de undersökta stålslaggerna var komplex med en stor variation av mineralfaser, främst kalciumsilikater, monticellit, periklas och en spinellfas. Andra möjliga mineralfaser var gehlenit, merwinit, åkermanit och järn. Förekomsten av olika fastfaslösningar i stålslaggsmineralerna är sannolik vilket kan orsaka förskjutningar av topparna i diffraktogrammen. Kalcit identifierades också. Karbonatisering under en kort tid visade sig inte ha någon signifikant inverkan på mineralogin, förutom en viss kalcitbildning. Resultaten från studien bidrar till en bättre förståelse av stabiliteten för ljusbågsugns- och skänkslagg i den miljö som finns i ett tätskikt. Åldringen av slaggen resulterade i en reducerad utlakning av vissa element. För att kunna förutsäga det långsiktiga beteendet för åldrad slagg bör resultaten från den här studien kombineras med data från ett pågående åldringsförsök som inkluderar mekaniska tester samt ett fullskaligt fältförsök på Hagfors deponi. Analysmetoder som mer detaljerat kan karaktärisera mineralogin, till exempel svepelektronmikroskopi (SEM) och energidispersiv röntgenspektroskopi (EDX), bör också användas för att bättre kunna kvantifiera mineralfaserna och bestämma vilka spårelement som är vanligast i specifika mineraler.

  • 7. Diener, Silvia
    et al.
    Andreas, Lale
    Brännvall, Evelina
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Evaluation and discussion of steel slag mineralogy after ageing under laboratory and field conditions2010Ingår i: The 6th Intercontinental Landfill research Symposium, 2010, s. 107-109Konferensbidrag (Övrigt vetenskapligt)
  • 8.
    Diener, Silvia
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Herrmann, Inga
    Ecke, Holger
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Accelerated carbonation of ashes and steel slags in a landfill cover construction2008Ingår i: Proceedings of Second International Conference on Accelerated Carbonation for Environmental and Materials Engineering / [ed] Renato Baciocchi; Giulia Costa; Alessandra Polettini; Raffaella Pomi, University of Rome "La Sapienza" , 2008, s. 389-400Konferensbidrag (Refereegranskat)
    Abstract [en]

    Fly ash from biofuel incineration and slags from steel production were used in two full scale applications of cover constructions on municipal solid waste (MSW) landfills. The long-term stability of the cover materials is studied in a designed laboratory experiment. The impact of six environmental factors on accelerated carbonation is investigated over a period of three years. Leaching behaviour, acid neutralization capacity, mineral composition (XRD) and thermo gravimetrical behaviour (TG) are tested after different periods of ageing under different conditions. By now samples were taken after three and ten months of ageing. Multivariate data analysis was used for data evaluation. The results indicate the factors material, ageing time and carbon dioxide content of the atmosphere to be most relevant.

  • 9. Diener, Silvia
    et al.
    Andreas, Lale
    Herrmann, Inga
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Ecke, Holger
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Accelerated carbonation of steel slags in a landfill cover construction2010Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 30, nr 1, s. 132-139Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Steel slags from high-alloyed tool steel production were used in a full scale cover construction of a municipal solid waste (MSW) landfill. In order to study the long-term stability of the steel slags within the final cover, a laboratory experiment was performed. The effect on the ageing process, due to i.e. carbonation, exerted by five different factors resembling both the material characteristics and the environmental conditions is investigated. Leaching behaviour, acid neutralization capacity and mineralogy (evaluated by means of X-ray diffraction, XRD, and thermogravimetry/differential thermal analysis, TG/DTA) are tested after different periods of ageing under different conditions.Samples aged for 3 and 10 months were evaluated in this paper. Multivariate data analysis was used for data evaluation. The results indicate that among the investigated factors, ageing time and carbon dioxide content of the atmosphere were able to exert the most relevant effect. However, further investigations are required in order to clarify the role of the temperature.

  • 10.
    Diener, Silvia
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Herrmann, Inga
    Lagerkvist, Anders
    Mineral transformations in steel slag used as landfill cover liner material2007Ingår i: 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 , 2007, Vol. 1Konferensbidrag (Refereegranskat)
    Abstract [en]

    In Europe, 15.2 million tonnes of steel slags have been generated in 2004 (Euroslag, 2006) out if which almost 6 million tonnes came from electric arc furnace (EAF) steelmaking and secondary metallurgical processes. In the presented project from Luleå University of Technology, two types of EAF slag and one slag originating from secondary metallurgical processes named ladle slag are investigated. The chemical and physical properties of these slags have been studied in detail (Herrmann, 2006; Andreas et al., 2005). For utilising steel slags in the liner of a landfill cover the long-term stability of the minerals is of great importance. Therefore, the ageing of steel slag minerals is evaluated with the help of a laboratory experiment. Particularly, the research questions, the experimental set-up and the methodology are presented. The present paper is part of a research project of the Division of Waste Science and Technology at Luleå University of Technology, Sweden in cooperation with Uddeholm Tooling AB, Hagfors municipality and MiMeR (Mineral and Metal Recycling Research Centre). It is investigated if steel slags are stable as a landfill cover liner material. The long-term stability is evaluated by determining the factors influencing the mineralogy of the slags and possible mineral transformations through ageing under the environmental conditions in a liner. The experiment includes two similar types of EAF slag and one ladle slag. Each steel slag sample is made by mixing 50% EAF slag and 50% ladle slag, addition of water and compaction. The specimens are stored in boxes under different atmospheric conditions. A reduced multivariate design has been chosen to determine the impact of different factors on the slag mineralogy. The factors that are varied in the experiment are relative humidity, carbon dioxide and temperature of the atmosphere surrounding the slag material as well as ageing time and the quality of the water used for sample making (see table 1). Table 1. Factorial design for ageing experiment of steel slagsLowMiddleHighRelative humidity30% -100%Carbon dioxide content0.036 (air)20 % * 100 %Temperature5 °C30 °C60 °CTime 1 month6 months1 yearWater quality destilled water -LeachateThe ageing of minerals is expected to initiate mineral transformations in steel slags. Primary phases will alter into secondary mineral phases. Changes in mineralogy can influence the stability of the liner. To evaluate mineralogy and properties of the aged steel slag, different analyses will be performed after the storage time of the specimens. X-ray diffraction and scanning electron microscopy as well as shear strength, acid neutralisation capacity and cation exchange capacity will be included. A possible mineral transformation for an alkaline material as steel slags can be the reaction of calcium ions from calcium silicates with the carbon dioxide resulting in the precipitation of calcium carbonate. Through this carbonation reaction, the transport of carbon dioxide into the bulk of the specimen could be hindered by the reaction products. Therefore, surface morphology can influence mineral transformations. First results and evaluations will be presented at the conference. REFERENCES Andreas L., Herrmann I., Lidstrom-Larsson M. & Lagerkvist A. (2005) Physical properties of steel slag to be reused in a landfill cover, Sardinia 2005, Tenth International Waste Management and Landfill Symposium, S. Margherita di Pula, Cagliari, Italy; 3 - 7 October 2005Euroslag (2006) Legal status of Slags. Position Paper. January 2006. The European Slag Association - EUROSLAG. Duisburg, Germany.Herrmann I. (2006). Use of Secondary Construction Material in Landfill Cover Liners. Licentiate Thesis. Luleå University of Technology, Sweden.

  • 11. Diener, Silvia
    et al.
    Andreas, Lale
    Herrmann, Inga
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Results from a field study using steel industry slags in a landfill cover construction2008Konferensbidrag (Övrigt vetenskapligt)
  • 12.
    Diener, Silvia
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Brännvall, Evelina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Leaching properties of steel slags after ageing under laboratory and field conditions2010Ingår i: Third International Conference on Accelerated Carbonation for Environmental and Materials Engineering: ACEME10 : November 29 - December 1, 2010, Åbo Akademi University, Åbo/Turku, Finland : proceedings / [ed] Ron Zevenhoven., Åbo: Åbo Akademi University Press, 2010Konferensbidrag (Refereegranskat)
  • 13.
    Herrmann, Inga
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Diener, Silvia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lind, Lotta
    Steel slag used in landfill cover liners: laboratory and field tests2010Ingår i: Waste Management & Research, ISSN 0734-242X, E-ISSN 1096-3669, Vol. 28, nr 12, s. 1114-1121Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Stricter rules for landfilling within the EU have led to the closure of many landfills and a need for large amounts of cover liner materials. Therefore, the potential utilization of mixtures of electric arc furnace slag (EAFS) and ladle slag (LS), which are currently deposited in landfills, as a material for use as landfill liner was investigated. Laboratory analyses showed the mixtures to have similar compression strength to that of high-strength concrete and low hydraulic conductivity (<10-11 m s-1 in some cases). However, both their hydraulic conductivity and compaction properties were strongly affected by the time between adding water to the mixtures and compacting them (tests showed that a delay of 24 h can lead to an increase in hydraulic conductivity, so it should be compacted as soon as possible after mixing the material with water). In addition, the performance of a cover liner constructed using EAFS and LS was studied in a 2-year field trial on a landfill for municipal solid waste, in which the average amount of leachate collected from ten lysimeters was only 27 L m-2 year-1, easily meeting Swedish criteria for the permeability of covers on non-hazardous waste landfills (≤50 L m-2 year-1). Thus, the material seems to have promising potential for use in barrier constructions.

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