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  • 51.
    Sjöblom, Rolf
    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.
    Energy generation by waste incineration: the management of impregnated wood2015In: Energy and Sustainability VI / [ed] Whady Florez-Escobar; Farid Chejne; Fanor Mondragon; Carlos Brebbia, Southampton, UK: WIT Transactions on Ecology and The Environment , 2015, p. 89-100Conference paper (Refereed)
    Abstract [en]

    Landfilling of organic waste is no longer allowed in Sweden. Instead, essentially all such waste is being recycled, and about half of it goes to incineration which accounts for about 10% of the total need for heating of buildings. Incineration implies destruction of potentially harmful constituents in the waste, but does not destroy contaminant elements such as arsenic which almost exclusively originates from impregnated wood. Methods for identification of chromium, copper and arsenic in such wood are analysed as well as techniques for sorting it into two categories. If incinerated separately, these can give rise to ash with Cr, Cu and As, and ash with only Cu. The former ash has a small volume and can be stabilized/landfilled at a qualified facility, and the latter ash might be used for beneficiation of Cu. In addition, the contamination by As, especially, in other fuels will be small and consequently also in the ash, thus facilitating its use. It is found that such sorting may be achieved using visual inspection as well as x-ray fluorescence (XRF), whilst use of reagents does not appear to offer any advantage over these two. Both methods are already in industrial use in Sweden, thus proving the feasibility of segregation and stabilization of contaminants in impregnated wood.

  • 52.
    Carlsson, My
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Holmström, David
    Profu AB, Mölndal.
    Bohn, Irene
    NSR, North Western Scania Waste Management Company, Helsingborg.
    Bisaillon, Mattias
    Profu AB, Mölndal.
    Morgan-Sagastume, Fernando
    AnoxKaldnes AB, Klosterängsvägen 11A, 226 47 Lund.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Impact of physical pre-treatment of source-sorted organic fraction of municipal solid waste on greenhouse-gas emissions and the economy in a Swedish anaerobic digestion system2015In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 38, p. 117-125Article in journal (Refereed)
    Abstract [en]

    Several methods for physical pre-treatments of source sorted organic fraction of municipal solid waste (SSOFMSW) before for anaerobic digestion (AD) are available, with the common feature that they generate a homogeneous slurry for AD and a dry refuse fraction for incineration. The selection of efficient methods relies on improved understanding of how the pre-treatment impacts on the separation and on the slurry’s AD. The aim of this study was to evaluate the impact of the performance of physical pre-treatment of SSOFMSW on greenhouse-gas (GHG) emissions and on the economy of an AD system including a biogas plant with supplementary systems for heat and power production in Sweden. Based on the performance of selected Swedish facilities, as well as chemical analyses and BMP tests of slurry and refuse, the computer-based evaluation tool ORWARE was improved as to accurately describe mass flows through the physical pre-treatment and anaerobic degradation. The environmental and economic performance of the evaluated system was influenced by the TS concentration in the slurry, as well as the distribution of incoming solids between slurry and refuse. The focus to improve the efficiency of these systems should primarily be directed towards minimising the water addition in the pre-treatment provided that this slurry can still be efficiently digested. Second, the amount of refuse should be minimised, while keeping a good quality of the slurry. Electricity use/generation has high impact on GHG emissions and the results of the study are sensitive to assumptions of marginal electricity and of electricity use in the pre-treatment.

  • 53.
    Carlsson, My
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Naroznova, Irina
    Department of Environmental Engineering (DTU Environment), Technical University of Denmark.
    Möller, Jacob Steen
    Department of Environmental Engineering (DTU Environment), Technical University of Denmark.
    Scheutz, Charlotte
    Department of Environmental Science and Engineering, Technical University of Denmark.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Importance of food waste pre-treatment efficiency for global warming potential in life cycle assessment of anaerobic digestion systems2015In: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 102, p. 58-66Article in journal (Refereed)
    Abstract [en]

    A need for improvement of food waste (FW) pre-treatment methods has been recognized, but few life cycle assessments (LCA) of FW management systems have considered the pre-treatment with respect to input energy, loss of organic material and nutrients for anaerobic digestion (AD) and/or further treatment of the refuse. The objective of this study was to investigate how FW pre-treatment efficiency impacts the environmental performance of waste management, with respect to global warming potential (GWP). The modeling tool EASETECH was used to perform consequential LCA focusing on the impact of changes in mass distribution within framework conditions that were varied with respect to biogas utilization and energy system, representing different geographical regions and/or different time-frames. The variations of the GWP due to changes in pre-treatment efficiency were generally small, especially when biogas and refuse were substituting the same energy carriers, when energy conversion efficiencies were high and slurry quality good enough to enable digestate use on land. In these cases other environmental aspects, economy and practicality could be guiding when selecting pre-treatment system without large risk of sub-optimization with regards to GWP. However, the methane potential of the slurry is important for the net LCA results and must be included in the sensitivity analysis. Furthermore, when biogas is used as vehicle fuel the importance of pre-treatment is sensitive to assumptions and approach of modelling marginal energy which must be decided based on the focus and timeframe of the study in question

  • 54.
    Xue, K.
    et al.
    Institute for Environmental Genomics and Department of Microbiology and Plant Biology, University of Oklahoma, Norman.
    Nostrand, J.D. van
    Institute for Environmental Genomics and Department of Microbiology and Plant Biology, University of Oklahoma, Norman.
    Vangronsveld, Jaco
    Hasselt University, Centre for Environmental Sciences, Agoralaan Building D, B-3590 Diepenbeek.
    Witters, N.
    Hasselt University, Centre for Environmental Sciences, Agoralaan Building D, B-3590 Diepenbeek.
    Janssen, Jolien
    Hasselt University, Centre for Environmental Sciences, Agoralaan Building D, B-3590 Diepenbeek.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Siebielec, Grzegorz
    Institute of Soil Science and Plant Cultivation - State Research Institute.
    Galazka, Rafal
    Institute of Soil Science and Plant Cultivation - State Research Institute.
    Giagnoni, L.
    University of Florence, Department of Agrifood Production and Environmental Sciences, P.le delle Cascine 28, I-50144 Florence.
    Arenella, Mariarita
    Department of Plant, Soil and Environmental Sciences, University of Florence.
    Zhou, J-Z
    Institute for Environmental Genomics and Department of Microbiology and Plant Biology, University of Oklahoma, Norman.
    Renella, Giancarlo
    University of Florence, Department of Agrifood Production and Environmental Sciences, P.le delle Cascine 28, I-50144 Florence, Department of Plant, Soil and Environmental Sciences, University of Florence, University of Florence.
    Management with willow short rotation coppice increase the functional gene diversity and functional activity of a heavy metal polluted soil2015In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 138, p. 469-477Article in journal (Refereed)
    Abstract [en]

    We studied the microbial functional diversity, biochemical activity, heavy metals (HM) availability and soil toxicity of Cd, Pb and Zn contaminated soils, kept under grassland or short rotation coppice (SRC) to attenuate the risks associated with HM contamination and restore the soil ecological functions. Soil microbial functional diversity was analyzed by the GeoChip, a functional gene microarray containing probes for genes involved in nutrient cycling, metal resistance and stress response. Soil under SRC showed a higher abundance of microbial genes involved in C, N, P and S cycles and resistance to various HM, higher microbial biomass, respiration and enzyme activity rates, and lower HM availability than the grassland soil. The linkages between functional genes of soil microbial communities and soil chemical properties, HM availability and biochemical activity were also investigated. Soil toxicity and N, P and Pb availability were important factors in shaping the microbial functional diversity, as determined by CCA. We concluded that in HM contaminated soils the microbial functional diversity was positively influenced by SRC management through the reduction of HM availability and soil toxicity increase of nutrient cycling. The presented results can be important in predicting the long term environmental sustainability of plant-based soil remediation.

  • 55.
    Rousta, Kamran
    et al.
    Swedish Centre for Resource Recovery, University of Borås.
    Bolton, Kim
    Physics Department, Göteborg University, Swedish Centre for Resource Recovery, University of Borås.
    Lundin, Magnus
    Swedish Centre for Resource Recovery, University of Borås.
    Dahlén, Lisa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Quantitative assessment of distance to collection point and improved sorting information on source separation of household waste2015In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 40, p. 22-30Article in journal (Refereed)
    Abstract [en]

    The present study measures the participation of households in a source separation scheme and, in particular, if the household’s application of the scheme improved after two interventions: (a) shorter distance to the drop-off point and (b) easy access to correct sorting information. The effect of these interventions was quantified and, as far as possible, isolated from other factors that can influence the recycling behaviour. The study was based on households located in an urban residential area in Sweden, where waste composition studies were performed before and after the interventions by manual sorting (pick analysis). Statistical analyses of the results indicated a significant decrease (28%) of packaging and newsprint in the residual waste after establishing a property close collection system (intervention (a)), as well as significant decrease (70%) of the miss-sorted fraction in bags intended for food waste after new information stickers were introduced (intervention (b)). Providing a property close collection system to collect more waste fractions as well as finding new communication channels for information about sorting can be used as tools to increase the source separation ratio. This contribution also highlights the need to evaluate the effects of different types of information and communication concerning sorting instructions in a property close collection system.

  • 56.
    Lagerkvist, Anders
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Pelkonen, Markku
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Wikström, Tommy
    Quick-start of full-scale anaerobic digestion (AD) using aeration2015In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 38, p. 102-104Article in journal (Refereed)
    Abstract [en]

    A conventional 1300 m3 continuously stirred anaerobic tank reactor at the city of Boden, north Sweden, which was receiving a feed of both sewage sludge and food waste, was put out of operation due to the build-up of a float phase. The reactor was emptied and cleaned. At start-up there was no methanogenic sludge available, so an unconventional start-up procedure was applied: The reactor was rapidly (8 days with 1200 kg of total solids (TS) added daily) filled with thickened, and slightly acidic sewage sludge, showing only slight methane generation, which was subsequently heated to 55 °C. Then compressed air was blown into the digester and within a month a fully functional methanogenic culture was established. The transfer from acidogenic to methanogenic conditions happened in about one week. As a start-up technique this is fast and cost efficient, it only requires the access of a compressor, electricity and a source of air. In total, about 16 tonnes of oxygen were used. It is proposed that this method may also be used as an operational amendment technique, should a reactor tend to acidify.

  • 57.
    Rousta, Kamran
    et al.
    Högskolan i Borås.
    Dahlén, Lisa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Source Separation of Household Waste: Technology and Social Aspects2015In: Resource Recovery to Approach Zero Municipal Waste, Boca Raton: CRC Press, Taylor & Francis Group, , 2015, p. 61-76Chapter in book (Other (popular science, discussion, etc.))
    Abstract [en]

    Ch 4. Separate collection, i.e. source separation, of recyclable materials is crucial for sustainable management of household waste. Functioning and efficient source separation schemes require consideration of the local circumstances and understanding of the influential of behavioural factors pertaining to householders. There are a number of different approaches and technical systems used for source separation. This chapter discusses the role of citizens and presents examples of comprehensive source separation systems. Some recommendations for establishing, monitoring and evaluating separate collection systems concludes the chapter.

  • 58.
    Xu, Jingying
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Bravo, Andrea Garcia
    Department of Ecology and Genetics, Limnology, University of Uppsala.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Bertilsson, Stefan
    Department of Ecology and Genetics, Limnology, University of Uppsala.
    Sjöblom, Rolf
    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.
    Sources and remediation techniques for mercury contaminated soil2015In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 74, p. 42-53Article in journal (Refereed)
    Abstract [en]

    Mercury (Hg) in soils has increased by a factor of 3 to 10 in recent times mainly due to combustion of fossil fuels combined with long-range atmospheric transport processes. Other sources as chlor-alkali plants, gold mining and cement production can also be significant, at least locally. This paper summarizes the natural and anthropogenic sources that have contributed to the increase of Hg concentration in soil and reviews major remediation techniques and their applications to control soil Hg contamination. The focus is on soil washing, stabilisation/solidification, thermal treatment and biological techniques; but also the factors that influence Hg mobilisation in soil and therefore are crucial for evaluating and optimizing remediation techniques are discussed. Further research on bioremediation is encouraged and future study should focus on the implementation of different remediation techniques under field conditions.

  • 59.
    Sjöblom, Rolf
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lagerkvist, Signe
    Umeå university.
    Sustainability of combustion and incineration of renewable fuels: the example of Sweden2015In: Biomass to biofuels, Southampton: WIT Press, 2015, p. 215-226Chapter in book (Refereed)
    Abstract [en]

    According to the statistics at the EC Commission, Sweden is the Champion byfar in Europe in terms of renewable energy. It comprised around 45% of the totalin the year 2008. This position has been reached by a combination of naturalresources, political determination and technology development.A major contributor to this is the extensive utilization of district heatingwhich amounts to around 50 TWh per year, and which covers about half of thetotal need for industrial and domestic buildings. The district heating is basedmainly on combustion of bio fuels together with waste and some peat.This practice is generally very positive from a sustainability perspective forthe following reasons: (1) bio fuels are renewable, and so is peat, although over a longer time span; (2) waste is being recovered for energy purposes; and (3) ash material is, in many cases, re-circulated and recycled.However, sustainability is not only about total percentages, but also on thequality in the processes, especially in terms of qualification of fuels and ashesand the associated possibilities for more efficient combustion and incinerationprocesses as well as ash utilization. Efficiency in this regard of course alsoincludes protection of health and the environment. These aspects are explored in a technical as well as a legal perspective, and some possibilities for furtherdevelopment and improvement are identified and discussed.The compilation and analyses are based on more than ten years of researchreports (mostly in Swedish) financed by District Heating in Sweden (SvenskFjärrvärme), [The Swedish] Thermal Engineering Research Institute(Värmeforsk), the Swedish Waste Management (Avfall Sverige) and SvenskaEnergiaskor AB (which translates to: “Swedish Energy Ashes Inc.”).Keywords: sustainable, combustion, incineration, bio fuels, waste, ash, Sweden.

  • 60.
    Travar, Igor
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kihl, Anders
    Rang-Sells Avfallsbehandling AB.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    The release of As, Cr and Cu from contaminated soil stabilized with APC residues under landfill conditions2015In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 151, p. 1-10Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate the stability of As, Cr and Cu in contaminated soil treated with air pollution control residues under landfill conditions. The influence of landfill gas and temperature on the release of trace elements from stabilized soil was simulated using a diffusion test. The air pollution control residues immobilized As through the precipitation of Ca–As minerals (calcium arsenate (Ca5H2(AsO4)3 × 5H2O), weilite (CaAsO4) and johnbaumite (Ca5(AsO4)3(OH)), incorporation of As into ettringite (Ca6Al2(SO4)3(OH)12 × 26H2O) and adsorption by calcite (CaCO3). The air pollution control residues generally showed a high resistance to pH reduction, indicating high buffer capacity and stability of immobilized As in a landfill over time. Generation of heat in a landfill might increase the release of trace elements. The release of As from stabilized soil was diffusion-controlled at 60 °C, while surface wash-off, dissolution, and depletion prevailed at 20 °C. The air pollution control residues from the incineration of municipal solid waste immobilized Cr, indicating its stability in a landfill. The treatment of soil with air pollution control residues was not effective in immobilization of Cu. Contaminated soils treated with air pollution control residues will probably have a low impact on overall leachate quality from a landfill.

  • 61.
    Travar, Igor
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    The use of air pollution control residues in landfill covers and for soil stabilization2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    About 66% of all heat energy generated in Sweden originates from the incineration of municipal solid waste and biofuels such as wood, cardboard and peat. In addition to heat energy, incinerators generate about 1.7 Mt of ashes each year, of which 500 000 t are air pollution control (APC) residues. APC residues from municipal solid waste incineration are usually landfilled whereas those from biofuel incinerators are used in roads, as soil fertilizers, and as amendments for stabilizing APC residues classified as hazardous waste. The physico-chemical properties of compacted APC residues are such that they could be viable alternatives to clay in landfill cover liners, and could also replace cement in cases where a solidified structure is desired. However, APC residues are classified as waste and their use may rise concern due to the release of harmful substances into the environment. This thesis examines the environmental impact of APC residues when used together with other waste materials (e.g. sewage sludge, bottom ash, compost) in a landfill cover. In addition, the suitability of APC residues as amendments for stabilizing contaminated soil and their effect on the stability of treated soil under landfill conditions was investigated. The environmental impacts of alternative landfill cover were evaluated by field and laboratory tests that examined two water streams: the landfill cover’s drainage water and its leachate. The drainage water that seeps above the landfill cover liner and is drained away from a landfill cover was contaminated with Cl-, N, TOC and the trace elements As, Cu, Mo, Ni, Se, Pb and Zn. This water stream will need treatment for at least three to four decades. The amounts of landfill cover leachate that percolated through the liner in the field test ranged from 3 to 30 l (m2 y)-1, which was below the legal limit on the leachate flow in non-hazardous waste landfills (

  • 62.
    Travar, Igor
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kihl, Anders
    Rang-Sells Avfallsbehandling AB.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Utilization of air pollution control residues for the stabilization/solidification of trace element contaminated soil2015In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 22, no 23, p. 19101-19111Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to evaluate the stabilization/solidification (S/S) of trace element-contaminated soil using air pollution control residues (APCRs) prior to disposal in landfill sites. Two soil samples (with low and moderate concentrations of organic matter) were stabilized using three APCRs that originated from the incineration of municipal solid waste, bio-fuels and a mixture of coal and crushed olive kernels. Two APCR/soil mixtures were tested: 30 % APCR/70 % soil and 50 % APCR/50 % soil. A batch leaching test was used to study immobilization of As and co-occurring metals Cr, Cu, Pb and Zn. Solidification was evaluated by measuring the unconfined compression strength (UCS). Leaching of As was reduced by 39–93 % in APCR/soil mixtures and decreased with increased amounts of added APCR. Immobilization of As positively correlated with the amount of Ca in the APCR and negatively with the amount of soil organic matter. According to geochemical modelling, the precipitation of calcium arsenate (Ca3(AsO4)2/4H2O) and incorporation of As in ettringite (Ca6Al2(SO4)3(OH)12 · 26H2O) in soil/APCR mixtures might explain the reduced leaching of As. A negative effect of the treatment was an increased leaching of Cu, Cr and dissolved organic carbon. Solidification of APCR/soil was considerably weakened by soil organic matter.

  • 63.
    Carlsson, My
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    When and why is pre-treatment of substrates for anaerobic digestion useful?2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Anaerobic digestion (AD) plays a key role in the recovery of renewable energy, in the form of biogas, and nutrients from waste materials. Pre-treatment of AD substrates has the potential to improve process performance in terms of increased methane yield and solids reduction, but pretreatments are not yet widely implemented into full-scale AD systems. The aims of this thesis were to identify conditions that determine when pre-treatment has a positive impact on an AD system and ways to improve the practical utility of pre-treatment impact assessment. Key steps towards meeting these aims were to determine and critically analyse effects of pre-treatments on AD, and current evaluation schemes at three levels: AD substrate level – Direct effects on the substrate’s chemical and physical characteristics and its biodegradability/bioavailability; Local AD system level – Effects of pre-treatment on the AD process and its outputs, required inputs and (local) upstream and downstream processes. System boundaries are “at the gate” of the AD plant and the system analysis may consider energy and/or financial parameters; Expanded AD System level – Includes indirect effects of pre-treatment, with system boundaries including external processes. The system analysis may address environmental and/or economic effects. Different substrate traits represent different types and degrees of limitations to optimal AD performance that can be met by different pre-treatment mechanisms. Most importantly, potential mechanical problems must be handled by dilution and/or homogenisation and unwanted components, as generally found in source-sorted food waste from households (FW), must be separated. These traits may hinder the actual operation of AD and the potential for recovery of nutrients, which is often the motivation for biological waste treatment. When these practical barriers are overcome, pre-treatment focus may be directed towards maximizing the conversion of organic material to biogas, which is potentially limited by the rate and/or extent of hydrolysis. Lignocellulosic structures and aerobically stabilised biological sludge represent significant barriers to hydrolysis, which can be overcome by pre-treatment-induced solubilisation. Other particulates are merely hydrolysis-limited by their size, which can be reduced by specific pre-treatments. Finally, substrates may contain non-biodegradable organic compounds, which need to be chemically transformed in order to be converted to biogas. The substrates considered for AD incorporate these traits in varying degrees and even among substrates of the same category, such as plant material and excess sludge from wastewater treatment (WWT), the potential effect of pretreatments may vary considerably. Overcoming the substrate barriers via pre-treatment may potentially improve the AD system by enhancing operational stability, increasing methane yields and solids reduction under similar operating conditions to those without pre-treatment or by increasing methane productivity by allowing reductions in hydraulic retention time without changing the methane yield. However, the required inputs as well as the associated effects on related sub-processes must also be considered. The ultimate usefulness of a pre-treatment in a specific system is determined by the mass- and energy balance and the associated financial or environmental costs/values of inputs and outputs. The accuracy and applicability of pre-treatment impact assessment is challenged by method limitations and lack of transparency. A common measure of the pre-treatment effects is COD solubilisation, but the interpretation is complicated by the application of different measurementapproaches. In addition, solubilisation of COD as a result of pre-treatment does not necessarily translate into increases in operational methane yields. This is due to potential formation of refractory compounds and the fact that hydrolysis is not necessarily rate limiting for all particulates. Pre-treatments’ effects on biodegradability and degradation rates can be better assessed by BMP tests (biochemical methane potential), provided that the test conditions are appropriate and the tests’ limitations are properly considered. However, extrapolation of BMP results to continuous processes is complicated by the batch mode of the tests. On the other hand, results from continuous trials allow assessments of methane yields in practical systems and the digestate’s physico-chemical properties, but are inevitably tied to the specific process conditions tested. Thus, results from multiple experimental conditions, possibly strengthened by computer simulations, are necessary for generalisations of pre-treatment effects on AD process performance. Pre-treatments have the potential to considerably improve AD systems, but their implementation must to be guided by the actual improvement potential of the specific substrate and valued in theirspecific context with respect to process design and framework conditions.

  • 64.
    Wang, Yu
    et al.
    School of Engineering, Aalto University, Espoo.
    Pelkonen, Markku
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kaila, Juha
    School of Engineering, Aalto University, Espoo.
    Are there carbon and nitrogen sinks in the landfills?2014In: Sustainable Environment Research, ISSN 1022-7636, Vol. 24, no 6, p. 423-429Article in journal (Refereed)
    Abstract [en]

    The management of sanitary landfills after closure is an important engineering, economic and sustainability issue. The society needs sustainable methods for landfilling from an environmental perspective but it has to be cost-effective and affordable for a society as well. Compared with inorganics, carbon and nitrogen are more reactive. It is important to identify the time needed for them to achieve the limit values of leachate emission (i.e., the length of aftercare period). However, does it mean that the environmental impacts have been minimized after the active aftercare period? Especially at low temperature, the decomposition rate and release rate of carbon and nitrogen are lower; so the leachate emission concentrations are lower and it is easier to achieve the emission limit values. In these conditions the residual carbon and nitrogen remaining in the landfill are higher, but according to the results this is not a practical problem. In the degradation of stable humic compounds, carbon and nitrogen sinks are formed. Their fraction in the organics seems to be comparable with waste treated in mechanical-biological way and has impact as a sink. The humification process seems to be affected by temperature, but more knowledge is still needed like total balances of humic substances. It is necessary to discuss the performance of carbon and nitrogen within aftercare (active aftercare) and after aftercare (passive aftercare). The solutions should be designed accordingly from both environmental and economic considerations.

  • 65.
    Kumpiene, Jurate
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Niero, L.
    Universita Degli Studi di Padova.
    Chemically stabilized arsenic-contaminated soil for landfill covers2014In: One century of the discovery of arsenicosis in Latin America (1914-2014): As 2014 - proceedings of the 5th international congress on arsenic in the environment / [ed] Marta I. Litter, Boca Raton,Ffla.: CRC Press, 2014, p. 842-843Conference paper (Refereed)
    Abstract [en]

    Arsenic (As) stabilization using zerovalent iron (Fe0) and its combination with peat was investigated in soil used as a pilot scale landfill cover in Northern Sweden. Leachate percolating through a 2 m thick layer of treated and untreated soil was collected in field. Chemical fractionation using sequential extraction, phytotoxicity test with dwarf beans and bioaccessibility tests simulating gastric solution were performed to assess the residual risks to the environment and human health. The results show that the exchangeable As-fraction in stabilized soils decreased when compared to the untreated soil, while other fractions remained unaffected. All the morphological parameters of plants improved and the bioaccessible As-fraction significantly decreased in the Fe-peat treated soil. The analysis of the leachates collected in field showed a substantially decreased As concentration in the Fe-peat amended soil. Further sampling is on-going in order to determine whether or not the treatment is successful in a long-term.

  • 66.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Classification of ash as hazardous or non-hazardous waste2014Conference paper (Refereed)
    Abstract [en]

    Combustion and incineration are utilized extensively in Sweden for the generation of heat and electricity. Substantial volumes of ash with varying chemical composition are also generated in the process. Classification of such ash as hazardous or non-hazardous under the European union legislation is, in principle, a “mission impossible” since the chemical forms of the inorganic components are very complex. Consequently, a method has been identifiedaccording to which reference substances are selected such that they represent the hazards of the actual forms of those trace elements that might influence health and the environment. The reference substances have been selected such that the hazard is not underestimated, that the result becomes reasonable realistic and that the evaluation is feasible to carry out. There areindications, especially with regard to ecotoxicity, that the method is overly cautious, and a potential is identified for combining testing with information from Authority data bases. It is explained and exemplified that ash may be very susceptible to ageing, and that this in many cases, and for most of the elements of interest, may improve the properties considerably. This not only influences the status of an ash with regard to the acceptance criteria for landfilling, butalso influences the classification. Leach properties are important when the degree of solid solution is to be assessed. Elements with similar properties, especially regarding their ionic radii, tend to exchange for each other even in solids. The effect is strongest for those elements that are the lowest abundance. Solid solution effects may lead to that trace elements become as inaccessible as the major elements in a certain crystalline phase. Iron(hydr)oxides and other ironrich phases frequently act as sinks for chromium, nickel and zinc, and in many cases this implies that most of these elements may not contribute to a classification as hazardous. The method has been applied to around 30 facilities with typically several ashes at each facility. It is concluded that this approach has lead to that many ashes have been classified in a cautious bur also reasonably realistic manner which at the same time has been practical.

  • 67.
    Brännvall, Evelina
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Zamora, Carles Belmonte
    LTU.
    Sjöblom, Rolf
    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.
    Effect of industrial residue combinations on availability of elements2014In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 276, p. 171-181Article in journal (Refereed)
    Abstract [en]

    Industrial residues, such as fly ashes and biosolids, contain elements (e.g. N, P, K, S, Ca and Zn) that make them a viable alternative for synthetic fertilizers in forestry and agriculture. However, the use of these materials is often limited due to the presence of potentially toxic substances. It is therefore necessary to assess and, when warranted, modify the chemical and physical form of these and similar waste materials before any advantages are taken of their beneficial properties. Biofuel fly ash, municipal solid waste incineration (MSWI) fly ash, biosolids, peat, peat residues and gypsum board waste were combined in various proportions, and this resulted in increased leaching of N, P, S, Cu and Mn, but decreased leaching of Ca, K, Mg, Cr, Fe, Ni, Zn, Al, As and Pb. Chemical fractionation revealed that elements Ca, K, Mg, S and Mn were predominantly exchangeable, while the rest of the elements were less mobile. Cadmium was mostly exchangeable in MSWI fly ash, but less mobile in biofuel fly ash mixtures. Recycling of MSWI fly ash in the mixtures with fertilizers is considerably less attractive, due to the high levels of salts and exchangeable Cd.

  • 68.
    Brännvall, Evelina
    et al.
    Luleå University of Technology, Professional Support, Externfinansiering. Waste Science and Technology, Luleå University of Technology.
    Nilsson, Malin
    Waste Science and Technology, Luleå University of Technology.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering. Waste Science and Technology, Luleå University of Technology.
    Skoglund, Nils
    Umeå University. Department of Applied Physics and Electronics.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering. Waste Science and Technology, Luleå University of Technology.
    Effect of residue combinations on plant uptake of nutrients and potentially toxic elements2014In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 132, p. 287-295Article in journal (Refereed)
    Abstract [en]

    The aim of the plant pot experiment was to evaluate potential environmental impacts of combined industrial residues to be used as soil fertilisers by analysing i) element availability in fly ash and biosolids mixed with soil both individual and in combination, ii) changes in element phytoavailability in soil fertilised with these materials and iii) impact of the fertilisers on plant growth and element uptake.Plant pot experiments were carried out, using soil to which fresh residue mixtures had been added. The results showed that element availability did not correlate with plant growth in the fertilised soil with. The largest concentrations of K (3534mg/l), Mg (184mg/l), P (1.8mg/l), S (760mg/l), Cu (0.39mg/l) and Zn (0.58mg/l) in soil pore water were found in the soil mixture with biosolids and MSWI fly ashes; however plants did not grow at all in mixtures containing the latter, most likely due to the high concentration of chlorides (82g/kg in the leachate) in this ash. It is known that high salinity of soil can reduce germination by e.g. limiting water absorption by the seeds. The concentrations of As, Cd and Pb in grown plants were negligible in most of the soils and were below the instrument detection limit values.The proportions of biofuel fly ash and biosolids can be adjusted in order to balance the amount and availability of macronutrients, while the possible increase of potentially toxic elements in biomass is negligible seeing as the plant uptake of such elements was low. © 2013 Elsevier Ltd.

  • 69.
    Nilsson, Mirja
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Environmental assessment of bottom ash pre-treated with zero valent iron2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Bottom ash has similar properties as crushed rocks and gravel, andcould replace some of the 40 million tonnesof virgin material used for road constructions each year.However, results presented in the literature indicate thatthe leaching of e.g. Cr, Cu, Mo, Pb and Zn can cause athreat to the sur rounding environment if the materialis used as it is. A common pre-treatment method is carbonation, whichwill reduce the pH and thereby decrease the leaching of several metals. This treatment is however not always enough, so alternative methods areneeded. One possibility could be to increase the number of sorption sites for the metals. The importance of iron oxides as sorption sits for metals isknown from both mineralogical studies of bottom ash as well as from theremediation of contaminated soil, where iron is used as an amendment.Zero valent iron (Fe 0) was therefore added prior to accelerated agingin order to increase the number of adsorption sites for metals and thereby improving the leaching quality. The performed leaching tests showed that theaddition of Fe 0 prior to accelerated aging improved the quality of the leachate compared with untreated bottom ash. There was also a significant de crease of Cu, Cr, Mo and Zn from bottom ash treated with Fe0 prior to accelerated aging com pared with bottom ash submitted to only accelerated aging. In order to make an environmental assessment of the bottom ash pretreated with Fe 0 prior to accelerated aginggeochemical modeling was performed using different pH and redox potentialsin order to simulate variations in the environment.The results in dicated that the leaching of Cr, Cr, Mo and Pb would not cause harm to the environment.Zn, however, was affected by changes in pH and leached in harmful aounts at pH values velow 6 and above 10.There are reasons to question the results from the geochemical modellingsince the results from pH-stat tests showedthat several elements leached at potentially harmful levelsat several of the tested pH. To fully evaluate the effect of addition of Fe0should the mineralogy of the pretreated bottom ash be evaluated further, in order to see what forms iron oxides are pre sent and if other metals are associated with them. However, in order to improve the quality of bottom ash,focus should be directed torwards what type of wastes that areincinerated and on the incineration process.

  • 70.
    Lindmark, Johan
    et al.
    School of Business, Society and Engineering, Mälardalen University, Västerås.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Nilsson, Erik
    School of Business, Society and Engineering, Mälardalen University, Västerås.
    Carlsson, My
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Thorin, Eva
    School of Business, Society and Engineering, Mälardalen University, Västerås.
    Dahlquist, Erik
    School of Business, Society and Engineering, Mälardalen University, Västerås.
    Evaluating the Effects of Electroporation Pre-treatment on the Biogas Yield from Ley Crop Silage2014In: Applied Biochemistry and Biotechnology, ISSN 0273-2289, E-ISSN 1559-0291, Vol. 174, no 7, p. 2616-2625Article in journal (Refereed)
    Abstract [en]

    Exploiting the full biogas potential of some types of biomass is challenging. The complex structures of lignocellulosic biomass are difficult to break down and thus require longer retention times for the nutrients to become biologically available. It is possible to increase the digestibility of the substrate by pre-treating the material before digestion. This paper explores a pre-treatment of ley crop silage that uses electrical fields, known as electroporation (EP). Different settings of the EP equipment were tested, and the results were analyzed using a batch digestion setup. The results show that it is possible to increase the biogas yield with 16 % by subjecting the substrates to 65 pulses at a field strength of 96 kV/cm corresponding to a total energy input of 259 Wh/kg volatile solid (VS). However, at 100 pulses, a lower field strength of 48 kV/cm and the same total energy input, no effects of the treatment were observed. The energy balance of the EP treatment suggests that the yield, in the form of methane, can be up to double the electrical energy input of the process.

  • 71.
    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

  • 72.
    Nordmark, Desiree
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Vestin, Jenny
    Sveriges Geotekniska Institut.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lind, Bo
    Sveriges Geotekniska Institut.
    Arm, Maria
    Sveriges Geotekniska Institut.
    Hallgren, Per
    Skogsstyrelsen.
    Geochemical Behavior of a Gravel Road Upgraded with Wood Fly Ash2014In: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 140, no 10, article id 5014002Article in journal (Refereed)
    Abstract [en]

    An insufficient bearing capacity of gravel roads is a common problem in Sweden during thaw periods. In this study, a gravel road at Timrå in central Sweden was mechanically stabilized by mixing 30% wood fly ash into the road base material. Testing of pollutant mobilization was performed both in the lab and at the field site over three years. The differences at a given liquid-to-solid ratio reached several orders of magnitude for some elements. K, Ca, Cl, and SO 4 were easily mobilized and found at elevated concentrations in leachate from the road one year after the road was stabilized. Two years after stabilization, the concentrations had returned to background levels. The stabilization also impacted the infiltration capacity of the road, reducing it by a factor of four. The weathering of Mg, Cu, and Zn from surrounding soil was higher, while the leaching of Al and K was higher from the amended road. Using fly ash in this fashion did not result in any noticeable adverse environmental impacts

  • 73.
    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.

  • 74.
    Nordmark, Desiree
    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.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Industrial By-products used in a Landfill Cover2014Conference paper (Refereed)
    Abstract [en]

    A small industrial waste landfill in Obbola, Northern Sweden is being completed and a final cover is installed. The landfill is owned and used by SCA Packaging, a paper mill factory nearby. An alternative final cover will be used, consisting mainly of industrial by-products from the paper mill. The aim of using industrial by-products is to save virgin materials, not to use synthetic materials and to make a cost-effective and environmentally safe closure of the landfill, while relevant laws and regulations are complied to.

  • 75.
    Xu, Jingying
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Kleja, Dan B
    Swedish Geotechnical Institute.
    Biester, Harald
    Department of Environmental Geochemistry, Institute of Geoecology, University of Braunschweig.
    Lagerkvist, Anders
    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.
    Influence of particle size distribution, organic carbon, pH and chlorides on washing of mercury contaminated soil2014In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 109, p. 99-105Article in journal (Refereed)
    Abstract [en]

    Feasibility of soil washing to remediate Hg contaminated soil was studied. Dry sieving was performed to evaluate Hg distribution in soil particle size fractions. The influence of dissolved organic matter and chlorides on Hg dissolution was assessed by batch leaching tests. Mercury mobilization in the pH range of 3–11 was studied by pH-static titration. Results showed infeasibility of physical separation via dry sieving, as the least contaminated fraction exceeded the Swedish generic guideline value for Hg in soils. Soluble Hg did not correlate with dissolved organic carbon in the water leachate. The highest Hg dissolution was achieved at pH 5 and 11, reaching up to 0.3% of the total Hg. The pH adjustment was therefore not sufficient for the Hg removal to acceptable levels. Chlorides did not facilitate Hg mobilization under acidic pH either. Mercury was firmly bound in the studied soil thus soil washing might be insufficient method to treat the studied soil.

  • 76.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Long-term developments in residues from the processing of alum shale and possible remedies2014In: Energy production and management in the 21st century: the quest for sustainable energy / [ed] C.A. Brebbia; E.R. Magaril, Southampton: WIT Press, 2014, p. 789-800Conference paper (Refereed)
    Abstract [en]

    In large parts of the world, the gas market has changed dramatically due to the fracking of rock, including shale. It is also anticipated that significant changes will take place in the oil market due to the rapid introduction of the processing of shale for the purpose of oil and gas generation. Many fear that there will be substantial consequences for the environment, especially in the long term. The purpose of the present paper is to share some experiences from related historical activities in Sweden where alum shale has been used for oil extraction, burning of lime, alum production and uranium beneficiation. Legacies exist in terms of shale ash and fines as well as residues from the leaching of uranium, in quantities of a total of tens of millions of tonnes, and at various stages of remediation. The long-term integrity of these residues is analyzed with regard to the possibility of development of acid mine drainage, and in view of the low Ca and high S content. It is found that such developments cannot be excluded for the cases in which the alum shale had not been (properly) combusted. Waste materials having appropriately high pH acid buffering capacities to inhibit acidification are identified together with injection as a promising method of application. The need for mixing on a local scale is discussed together with the possible influence of the injection of slurry on ongoing fires. It is found that further knowledge is needed on a number of issues.

  • 77.
    Kumpiene, Jurate
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Brännvall, Evelina
    Luleå University of Technology, Professional Support. EXTfinansiering.
    Lagerkvist, Anders
    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.
    Project: North Waste Infrastructure2014Other (Other (popular science, discussion, etc.))
  • 78.
    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.

  • 79.
    Harder, Robin C.
    et al.
    Chalmers University of Technology, Department of Civil and Environmental Engineering.
    Kalmykova, Yuliya
    Chalmers University of Technology, Department of Civil and Environmental Engineering.
    Morrison, Gregory M.
    Chalmers University of Technology, Department of Civil and Environmental Engineering.
    Feng, Fen
    Chalmers University of Technology, Department of Civil and Environmental Engineering.
    Mangold, Mikael
    Chalmers University of Technology, Department of Civil and Environmental Engineering.
    Dahlén, Lisa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Quantification of goods purchases and waste generation at the level of individual households2014In: Journal of Industrial Ecology, ISSN 1088-1980, E-ISSN 1530-9290, Vol. 18, no 2, p. 227-241Article in journal (Refereed)
    Abstract [en]

    Quantifying differences in resource use and waste generation between individual households and exploring the reasons for the variations observed implies the need for disaggregated data on household activities and related physical flows. The collection of disaggregated data for water use, gas use, electricity use, and mobility has been reported in the literature and is normally achieved through sensors and computational algorithms. This study focuses on collecting disaggregated data for goods consumption and related waste generation at the level of individual households. To this end, two data collection approaches were devised and evaluated: (1) triangulating shopping receipt analysis and waste component analysis and (2) tracking goods consumption and waste generation using a smartphone. A case study on two households demonstrated that it is possible to collect quantitative data on goods consumption and related waste generation on a per unit basis for individual households. The study suggested that the type of data collected can be relevant in a number of different research contexts: eco-feedback; user-centered research; living-lab research; and life cycle impacts of household consumption. The approaches presented in this study are most applicable in the context of user-centered or living-lab research. For the other contexts, alternative data sources (e.g., retailers and producers) may be better suited to data collection on larger samples, though at a lesser level of detail, compared with the two data collection approaches devised and evaluated in this study

  • 80.
    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.

  • 81.
    Sjöblom, Rolf
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lindskog, Staffan
    Firma Lindskog.
    Reputation asset and environmental liability2014In: Environmental Impact II / [ed] C.A. Brebbia; G. Passerini; T-S. Chon, Southampton: WIT Press, 2014, p. 467-478Conference paper (Refereed)
    Abstract [en]

    The second largest asset to a company may well be its good reputation. Environmental liabilities warrant special attention in this regard since they may well constitute the largest uncertainty in an annual report, and it is not seldom discovered that they have been underestimated. The purpose of the paper is to compile and present a road map as to how to meet the legal and other requirements, and to analyse the alternatives of proactive and reactive approaches. The legal requirements are to be found in various pieces of legislation, on different topics, and with a highly varying degree of detail. It is found that general statements, including the polluter pays principle, together with the requirements on annual reporting provide a good basis for developing a company strategy. Further information about how to plan for decommissioning and restoration, including financial planning can be found in various recommendations and standards from e.g. IAEA, OECD/NEA and ASTM, and support on cost methods is available from AACE and ISPA. More detail can be found in various open sources such as journal articles, conference proceedings and books. It is concluded that a proactive strategy, which includes early technical and financial planning, is associated with the lowest overall costs, and can eliminate many of the otherwise potentially very troublesome cost raisers. It is also concluded that with proper planning, funding is to be made using untaxed assets. Using taxed assets can constitute an efficient road block against proper decommissioning and remediation actions. It is concluded that a proactive and proper management of environmental liabilities – if properly communicated – can constitute an important asset in terms of raised confidence among share holders, customers, interested parties and others.

  • 82.
    Carabante, Ivan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Mouzon, Johanne
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Grahn, Mattias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Fredriksson, Andreas
    Mining Technology R and D, LKAB Kiruna Mine.
    Hedlund, Jonas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Reutilization of porous sintered hematite bodies as effective adsorbents for arsenic(V) removal from water2014In: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045, Vol. 53, no 32, p. 12689-12696Article in journal (Refereed)
    Abstract [en]

    A method was developed to enhance the arsenic adsorption capacity of porous bodies of sintered hematite. The method comprised the formation of a coating of 1 wt % iron oxide nanoparticles on the raw material. The nanoparticles showed two distinct habits: spherical habit, likely ferrihydrite, and acicular habit, likely goethite and/or akaganéite. The specific surface area of the hematite raw material increased from 0.5 to 3.75 m2/g, and the adsorption capacity increased from negligible to 0.65 mg of [As]/g as calculated from equilibrium and breakthrough adsorption data. Equilibrium adsorption data of arsenate on the adsorbent from a solution at pH 5 followed the Langmuir model, while breakthrough adsorption data for a 500 μg/L arsenate solution at pH 5 followed the Thomas model. The adsorbed arsenic could be desorbed using distilled water at pH 12. These results show the potential for the reutilization of waste products comprising coarse hematite bodies as adsorbents.

  • 83.
    Kumpiene, Jurate
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Bert, Valérie
    INERIS, Technologies and Sustainable and Clean Processes, Parc Technologique Alata, BP2, 60550 Verneuil en Halatte.
    Dimitriou, Ioannis
    Swedish University of Agriculture Sciences, Department of Crop Production Ecology.
    Eriksson, Jan
    Swedish University of Agriculture Sciences, Department of Soil and Environment.
    Friesl-Hani, Wolfgang
    AIT Austrian Institute of Technology GmbH, Health and Environment Department.
    Galazka, Rafal
    Institute of Soil Science and Plant Cultivation - State Research Institute.
    Herzig, Rolf
    Phytotech Foundation and AGB, Quartiergasse 12, 3013 Bern.
    Janssen, Jolien
    Hasselt University, Centre for Environmental Sciences, Agoralaan Building D, B-3590 Diepenbeek.
    Kidd, Petra
    Instituto de Investigaciones Agrobiológicas de Galicia (IIAG), Consejo Superior de Investigaciones Científicas (CSIC), Santiago de Compostela.
    Mench, Michel
    UMR BIOGECO INRA 1202, Ecology of Communities, Bordeaux 1 University.
    Müller, Ingo
    Saxon State Office for Environment, Agriculture and Geology, Pillnitzer Platz 3, 01326 Dresden.
    Neu, Silke
    Saxon State Office for Environment, Agriculture and Geology, Pillnitzer Platz 3, 01326 Dresden.
    Oustriere, Nadège
    INRA, UMR1202 BIOGECO, F-33610 Cestas, France and Université de Bordeaux.
    Puschenreiter, Markus
    University of Natural Resources and Life Sciences Vienna — BOKU, Department of Forest and Soil Sciences.
    Renella, Giancarlo
    University of Florence, Department of Agrifood Production and Environmental Sciences, P.le delle Cascine 28, I-50144 Florence.
    Roumier, Pierre-Hevré
    Instituto de Investigaciones Agrobiológicas de Galicia (IIAG), Consejo Superior de Investigaciones Científicas (CSIC), Santiago de Compostela.
    Siebielec, Grzegorz
    Institute of Soil Science and Plant Cultivation - State Research Institute.
    Vangronsveld, Jaco
    Hasselt University, Centre for Environmental Sciences, Agoralaan Building D, B-3590 Diepenbeek.
    Manier, Nicolas
    INERIS, Expertise and Assays in Ecotoxicology, Parc Technologique Alata.
    Selecting chemical and ecotoxicological test batteries for risk assessment of trace element-contaminated soils (phyto)managed by gentle remediation options (GRO)2014In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 496, p. 510-522Article in journal (Refereed)
    Abstract [en]

    During the past decades a number of field trials with gentle remediation options (GRO) have been established on trace element (TE) contaminated sites throughout Europe. Each research group selects different methods to assess the remediation success making it difficult to compare efficacy between various sites and treatments. This study aimed at selecting a minimum risk assessment battery combining chemical and ecotoxicological assays for assessing and comparing the effectiveness of GRO implemented in seven European case studies. Two test batteries were pre-selected; a chemical one for quantifying TE exposure in untreated soils and GRO-managed soils and a biological one for characterizing soil functionality and ecotoxicity. Soil samples from field studies representing one of the main GROs (phytoextraction in Belgium, Sweden, Germany and Switzerland, aided phytoextraction in France, and aided phytostabilization or in situ stabilization/phytoexclusion in Poland, France and Austria) were collected and assessed using the selected test batteries. The best correlations were obtained between NH4NO3-extractable, followed by NaNO3-extractable TE and the ecotoxicological responses. Biometrical parameters and biomarkers of dwarf beans were the most responsive indicators for the soil treatments and changes in soil TE exposures. Plant growth was inhibited at the higher extractable TE concentrations, while plant stress enzyme activities increased with the higher TE extractability. Based on these results, a minimum risk assessment battery to compare/biomonitor the sites phytomanaged by GROs might consist of the NH4NO3 extraction and the bean Plantox test including the stress enzyme activities.

  • 84.
    Travar, Igor
    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.
    Kihl, Anders
    Rang-Sells Avfallsbehandling AB.
    Stabilization of As-contaminated soil with fly ashes2014In: One Century of the discovery of arsenicosis in Latin America (1914-2014): As 2014 - proceedings of the 5th international congress on arsenic in the environment / [ed] Marta I. Litter, Boca Raton, Fla.: CRC Press, 2014, p. 847-849Conference paper (Refereed)
    Abstract [en]

    The main aim of this study is to evaluate the stabilization of As-contaminated soil with Fly Ash (FA) and the environmental impact assessment of a soil/ash mixture after treatment. Two soil samples heavily contaminated with As were stabilized with two FA that originate from incineration of biofuels (BFA) and mixture of coal and crushed olive kernel (CFA). The As solubility was reduced between 39 and 93% in soil/ash mixtures. Leaching of As from soils decreased with increased amount of ash. Immobilization of As was positively correlated to pH and negatively correlated to the amount of organic matter in soil. Geochemical modeling showed that the release of As was controlled by Ca3(AsO4)2:4H2O in soil/ash mixtures that can be a possible explanation for the reduced solubility of As from soil/ash mixtures. A negative effect of the treatment was the mobilization of Cu from ashes and Dissolved Organic Carbon (DOC) from soil.

  • 85.
    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.

  • 86.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    The long-term effects of nuclear accidents2014In: Waste Management and the Environment VII / [ed] C.A. Brebbia; G. Passerini; H. Itoh, Southampton: WIT Press, 2014, p. 355-366Conference paper (Refereed)
    Abstract [en]

    The purpose of the present paper is to present some examples, based mainly on Swedish work, of late effects of nuclear accidents together with their implications and possible remedies, or absence of need for remedies. It took six years after the Three Mile Island accident before it was realized that the core was partially converted into very corrosion resistant corium which was distributed throughout the reactor system in the form of fines. It is essential that techniques for removal of such debris be developed for the Fukushima plant in order for large areas to become accessible. The ability of caesium-137 to bind irreversibly to soil material is essential in conjunction with ploughing, since it will not only imply self-shielding but also that caesium-137 is hindered from entering the groundwater as well as plants. Disposal of top soil material may be greatly facilitated if such immobilization can eliminate the need for a top seal. However, such operations are irreversible, and knowledge of the long-term properties of the soil material must be available before any decisions can be made. Thus, previous experience, especially on the long term behaviour is essential. Such long-term results are available in Sweden from tests started already in the early 60's. The issues have been studied in substantial detail since the level of protection has been much higher in Sweden than e. g. in Japan. Otherwise, the total fallouts are comparable in magnitude with Sweden receiving around 5% of the total from Chernobyl, and Japan receiving from Fukushima what corresponds to about 8 % of that from Chernobyl, all figured as caesium-137. The distribution is much more concentrated in Japan, however. The major need for protection in Sweden relates to ash and reindeer in which areas Authority restrictions still apply. Even modest levels of caesium-137 in the bio-fuel may lead to levels in the ash that warrant consideration.

  • 87.
    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.

  • 88.
    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)
  • 89.
    Xu, Jingying
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Feasibility study of soil washing to remediate mercury contaminated soil2013Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mercury (Hg) cannot be degraded. Therefore only two principal processes are available for the treatment of Hg-contaminated soil: (1) the separation of Hg from the soil or (2) the stabilisation of Hg within the soil. Prior to selecting a suitable treatment technique, it is necessary to have an understanding of Hg behaviour in contaminated soil, i.e., distribution in particle size fractions, dissolution at different pH and in the presence of chlorides, and mobilisation using various extractants. The thesis aims to evaluate the potential for applying soil washing to decontaminate the Hg-contaminated soil. The Hg contamination originated from inappropriate waste disposal, chlor-alkali process and harbour activities, and the soil was also polluted by other trace elements, i.e., Zn, Cu and Pb, etc. The soil was fractionated from fine to coarse particles to study the effectiveness of physical separation. A pH-static titration ranging from pH 3 to 11 was performed to assess the mobility of Hg in response to pH changes. The chloride influence on Hg mobilisation was studied using an HCl solution of different concentrations as the leachant. Batch leaching tests were used to evaluate Hg solubility in water, and extraction efficiency by various extractants. The extractants derived from wastes were acidogenic leachates generated from biodegradable wastes, and alkaline leachates produced from fly/bottom ashes. The studied soil consisted of dominant coarse-grained fractions, which is usually suitable for particle size separation. However, dry sieving has been shown to be insufficient to separate clean from contaminated soil fractions although the Hg concentrations decreased with increasing particle sizes. The reasons are likely to be: (i) the physical attachment of fines to coarse particles; (ii) the strong chemical bond of soil organic matter (OM) and minerals for Hg. Distilled water could barely mobilise the Hg from the soil, most likely due to firm chemical bonding between the soil and Hg. Despite the fact that enhanced Hg dissolution was observed at pH 5 and 11 in this study, soil washing by pH adjustment was insufficient for Hg removal. The introduction of chlorides did not facilitate the Hg mobilisation either. Retention of Hg in the soil by OM seemed to be predominant over Hg mobilisation by chlorides. Chemical extraction by leachates from wastes as well as EDTA solution and NaOH solutions showed that neither alkaline nor acidic leachates could facilitate Hg removal from the soil. Mercury was firmly bound in the soil matrix and no more than 1.5% of the total Hg could be removed by any of the tested extractants. Future research should therefore focus on the development of Hg immobilisation techniques.

  • 90.
    Xu, Jingying
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Kleja, Dan Berggren
    Department of Environmental Engineering, Swedish Geotechnical Institute.
    Lagerkvist, Anders
    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.
    Influence of soil particle size, organic carbon and pH on mercury distribution and dissolution in contaminated soil2013In: Influence of soil particle size, organic carbon and pH on mercury distribution and dissolution in contaminated soil, 2013, p. 45-Conference paper (Refereed)
    Abstract [en]

    Mercury (Hg) cannot be destroyed therefore only two principal processes are available for the treatment of Hg-contaminated soil: 1) separation of Hg from soil (through wet-sieving and/or chemical extraction), or 2) stabilization of Hg within the soil (through chemical immobilisation or stabilisation/solidification). If Hg separation is used, soil can be cleaned while Hg recovered. A complex matrix may, however, cause low treatment efficiency. Therefore, prior to selecting the suitable treatment technique, an understanding of Hg solubility and distribution in particle size fractions of the contaminated soil is necessary. The aim of this study was to evaluate the potential for applying soil washing technology to clean Hg contaminated soil based on Hg distribution in soil particle size fractions, Hg solubility in water and pH-dependant Hg dissolution. Soil contaminated by different industrial processes (e.g. waste dump, chlor–alkali process, harbour activities) was collected from Tidermans padding area upstream of Göta River, Sweden during the site remediation. The soil was dry sieved into particle-size fractions of <0.063 mm, 0.063–0.125 mm, 0.125–0.25 mm, 0.25–0.5 mm, 0.5–1 mm, 1–2 mm and 2–4 mm and along with the bulk soil were analysed for total Hg and total organic carbon (TOC). A batch leaching test at liquid-to-solid ratio (L/S) 10 was performed to determine water soluble Hg and dissolved organic carbon (DOC). A pH-static leaching test was performed to determine Hg solubility in the pH range of 3-11. All particle size fractions contained Hg above the Swedish guideline value for contaminated soil (2.5 mg/kg for less sensitive land use). Total Hg concentrations decreased with increasing particle size (except fraction 1-2 mm), ranging from 48.70 mg/kg to 10.29 mg/kg. The TOC contents were similar in all size fractions from 8.72 to 10.88 and had no correlation with the total Hg. Water soluble Hg was low in all size fractions, making up for 0.04% to 0.12% of the total Hg. Contents of DOC declined from fine to large fractions, however, no correlation between Hg solubility and DOC content has been observed. Mercury desorption was affected by pH and fluctuated throughout the tested pH range. The least Hg dissolution was achieved at pH=3 and pH 9 in all fractions and the bulk soil, while the dissolution peaks were observed at pH=5 and pH=11. The results show that the soil washing applying wet-sieving and particle separation method would be unfeasible since elevated Hg concentrations are distributed in all tested soil particle fractions and water solubility of Hg is very low. Chemical extraction focusing on pH 5 or pH 11 might improve the Hg removal. Geochemical modelling is being performed to understand this Hg behaviour in the studied soil.

  • 91.
    Sjöblom, Rolf
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Lindskog, Staffan
    Swedish Radiation Safety Authority.
    Andreas, Lale
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Long term aspects of landfilling and surface disposal: Lessons learned from nuclear and non-nuclear decommissioning, remediation and waste management2013In: Journal of Earth Sciences and Geotechnical Engineering, ISSN 1792-9040, E-ISSN 1792-9660, Vol. 2, no 2, p. 35-51Article in journal (Refereed)
    Abstract [en]

    The fields of landfilling of conventional waste and that of surface disposal of nuclear waste have developed quite independently and also partly out of phase with each other. The paper analyses what knowledge and experience might be mutually beneficial as well as what further knowledge may be needed.It is found that even though knowledge may exist, and information from lessons learned elsewhere be available, action may be subject to considerable initiation or incubation times. Legislation on financial reporting is summarized and its implications for early technical and financial planning are assessed. Prerequisites for long-term behaviour are analysed for the waste forms as well as for the seals and covers. The rationale for using natural and anthropogenic analogues is compiled, and alternative seals for landfills are analysed based on this information. Lessons learned from nuclear decommissioning are presented, and the difficulties encountered when the decommissioning takes place long times after commissioning and operation of a facility are illuminated. Comparison is made with contaminated soil in which area openly available domestic publications are lass abundant in some areas. The differences between end of license and end of responsibilities are clarified. Uranium-containing waste is presented as an example. Prerequisites are presented for natural uranium together with its progenies and for depleted uranium, initially without any daughters. It is found that both alternatives are associated with a number of issues to consider, and that both call for long-term containment for conventional chemical hazard and radiological hazard reasons.

  • 92.
    Nilsson, Mirja
    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.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Screening analysis of bottom ashes from waste incineration2013In: 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 , 2013Conference paper (Other academic)
    Abstract [en]

    Screening analysis of bottom ashes from waste incinerationA local waste-to-energy plant in Northern Sweden incinerates municipal solid waste (MSW). The bottom ash (BA) shall be used as construction material. To investigate the homogeneity of the BA, as a base for a more detailed characterisation, a screening was done on 0-10 mm samples taken daily during one month in an ash treatment plant for metal separation.The on-going characterisation focuses on the leaching of heavy metals from the BA as previous work (Oja 2012) showed that a number of trace metals (As, Cd, Cr, Cu, Ni, Pb and Zn) exceeds the limits set up by the Swedish EPA (Naturvårdsverket 2010) for the use of waste as construction material with regard to total content. Since Cu and Cr also exceed the leaching limits (L/S10), the bottom ash cannot be used without treatment. Ageing and the effect of immobilising amendments are studied with regard to their effect on the leaching behaviour.Material and MethodSamples of BA were taken after metal separation and sieving, daily during one month in 2012 resulting in 32 samples of two different fractions, 0-10 mm and 10-50 mm. A screening was performed on the 0-10 mm fraction analysing pH, EC both in duplicates and LOI, TS, and elemental composition using XRF on non-milled samples in triplicates. Results Based on the analyses made, no grouping of samples could be observed (figure 1), and therefore the material in each fraction was homogenized prior to further investigation. On-going studyDifferent treatment options such as accelerated ageing and stabilization with e.g. zero valent iron are investigated in an on-going study. Also, the effect of incineration parameters such as temperature, air flow and time, on the composition of the BA is studied through modelling (using Factsage). The overall goal is to improve the quality of the BA to an extent that it can be used in different ground constructions.The combined effects of weathering and iron amendment on the mineral composition and the leaching behaviour will be studied. The test program includes acid neutralization capacity (ANC), TOC, XRF, XRD analyses and a column test. Mechanical stability and freeze-thaw resistance will also be tested. Using the Factsage database the incineration process will be modelled with regard to possible changes in the composition of the BA.In addition to this work two field test areas (á 200 m2) will be installed using treated BA as base layer in a material processing and stockpile areas. The leachate will be collected using lysimeters and analysed monthly. Primary results will be available in late summer/early fall. References Naturvårdsverket (2010). Återvinning av avfall i anläggningsarbeten. Handbok 2010:1. Naturvårdsverket StockholmOja E. (2012). Botten aska som dräneringsskikt vid sluttäckning av deponier. Department of Environmental Engineering, Division of Waste Science and Technology, Luleå University of Technology

  • 93.
    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.

  • 94.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Sustainability of combustion and incineration of renewable fuels: example of Sweden2013In: Energy and sustainability IV / [ed] C.A. Brebbia; A.M. Marinov; C.A. Safta, Southampton: WIT Press, 2013, p. 173-184Conference paper (Refereed)
    Abstract [en]

    According to the statistics at the EC Commission, Sweden is the Champion byfar in Europe in terms of renewable energy. It comprised around 45% of the totalin the year 2008. This position has been reached by a combination of naturalresources, political determination and technology development.A major contributor to this is the extensive utilization of district heatingwhich amounts to around 50 TWh per year, and which covers about half of thetotal need for industrial and domestic buildings. The district heating is basedmainly on combustion of bio fuels together with waste and some peat.This practice is generally very positive from a sustainability perspective forthe following reasons: (1) bio fuels are renewable, and so is peat, although over alonger time span; (2) waste is being recovered for energy purposes; and (3) ashmaterial is, in many cases, re-circulated and recycled.However, sustainability is not only about total percentages, but also on thequality in the processes, especially in terms of qualification of fuels and ashesand the associated possibilities for more efficient combustion and incinerationprocesses as well as ash utilization. Efficiency in this regard of course alsoincludes protection of health and the environment. These aspects are explored ina technical as well as a legal perspective, and some possibilities for furtherdevelopment and improvement are identified and discussed.The compilation and analyses are based on more than ten years of researchreports (mostly in Swedish) financed by District Heating in Sweden (SvenskFjärrvärme), [The Swedish] Thermal Engineering Research Institute(Värmeforsk), the Swedish Waste Management (Avfall Sverige) and SvenskaEnergiaskor AB (which translates to: “Swedish Energy Ashes Inc.”).

  • 95.
    Lindskog, Staffan
    et al.
    Swedish Radiation Safety Authority.
    Labor, B.
    Badania Dydaktycne.
    Sjöblom, Rolf
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Sustainability of nuclear energy with regard to decommissioning and waste management2013In: International Journal of Sustainable Development and Planning, ISSN 1743-7601, E-ISSN 1743-761X, Vol. 8, no 2, p. 246-264Article in journal (Refereed)
    Abstract [en]

    Sustainability aspects of nuclear power are analysed with regard to such environmental liabilities that are associated with decommissioning of nuclear facilities and with nuclear waste management. Sustainability is defined and evaluated based on information searches that also include energy from combustion of coal. It is concluded that the claims on sustainability put forward by different parties are inconsistent and that coherent methodologies for evaluation are needed together with appropriately structured knowledge bases. Examples are presented from the perspective of the Swedish Radiation Safety Authority. It is found that nuclear power can qualify as sustainable only if the nuclear liability associated with protection of health and the environment - now and in the future – is appropriately managed. Sustainability awareness is analysed in a historic perspective, and it is found that it has been around for at least as long as agriculture, and that at least some of the shortcomings are actually modern inventions. Comprehensive perspectives are essential, since sustainability awareness may appear as trends. It is a historical fact that planning for decommissioning and estimation of associated costs are frequently treacherous exercises. However, costs must be relatively accurately estimated already at early stages so that adequate funds are available at the time when they are needed. Thus, the timing of the technical planning is often governed by the needs for financial planning. It is the duty of the present generation to assess what is adequate and to find responsible solutions. But the next generation should also be asked to carefully consider the perspective that they provide to us.

  • 96.
    Kumpiene, Jurate
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Desogus, Paolo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Schulenburg, Sven
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Arenella, Mariarita
    Department of Plant, Soil and Environmental Sciences, University of Florence.
    Renella, Giancarlo
    Department of Plant, Soil and Environmental Sciences, University of Florence.
    Brännvall, Evelina
    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.
    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.
    Utilisation of chemically stabilized arsenic-contaminated soil in a landfill cover2013In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 20, no 12, p. 8649-8662Article in journal (Refereed)
    Abstract [en]

    The aim of the study was to determine if an As-contaminated soil, stabilized using zerovalent iron (Fe0) and its combination with gypsum waste, coal fly ash, peat, or sewage sludge, could be used as a construction material at the top layer of the landfill cover. A reproduction of 2 m thick protection/vegetation layer of a landfill cover using a column setup was used to determine the ability of the amendments to reduce As solubility and stimulate soil functionality along the soil profile. Soil amendment with Fe0 was highly efficient in reducing As in soil porewater reaching 99 % reduction, but only at the soil surface. In the deeper soil layers (below 0.5 m), the Fe treatment had a reverse effect, As solubility increased dramatically exceeding that of the untreated soil or any other treatment by one to two orders of magnitude. A slight bioluminescence inhibition of Vibrio fischeri was detected in the Fe0 treatment. Soil amendment with iron and peat showed no toxicity to bacteria and was the most efficient in reducing dissolved As in soil porewater throughout the 2 m soil profile followed by iron and gypsum treatment, most likely resulting from a low soil density and a good air diffusion to the soil. The least suitable combination of soil amendments for As immobilization was a mixture of iron with coal fly ash. An increase in all measured enzyme activities was observed in all treatments, particularly those receiving organic matter. For As to be stable in soil, a combination of amendments that can keep the soil porous and ensure the air diffusion through the entire soil layer of the landfill cover is required.

  • 97.
    Sjöblom, Rolf
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Ecke, Holger
    Brännvall, Evelina
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Vitrified forts as anthropogenic analogues for assessment of long-term stability of vitrified waste in natural environments2013In: International Journal of Sustainable Development and Planning, ISSN 1743-7601, E-ISSN 1743-761X, Vol. 8, no 3, p. 380-399Article in journal (Refereed)
    Abstract [en]

    The area’s natural analogues, vitrifi ed forts, combustion technology, and vitrifi ed waste have been reviewed.The purpose was to identify if investigations of vitrifi ed rock in hill forts might be warranted for assessing thelong-term integrity of vitrifi ed waste in natural environments. Wastes that are being vitrifi ed include ash fromincineration of domestic waste, contaminated soil and fi ssion products from reprocessing of spent nuclear fuel.It was found that vitrifi ed materials in at least 200 hill forts constitute good anthropogenic analogues to vitrified waste. The compositions vary considerably from site to site and even within one site and may correspondrelatively well to the spans of parameters in the various vitrifi ed wastes. Glasses in vitrifi ed forts comparefavourably to archaeological artefacts which are soda- and potash-based and consequently have different corrosionbehaviours and may weather too quickly. Natural glasses might be too limited in composition variationand are perhaps also too durable. Combustion technology considerations based on quality of heat analysesindicate that at least some of the vitrifi cations of hill forts were carried out with the specifi c purpose of achievingstrong and durable constructions. This makes it considerably easier to envisage how the vitrifi cations mighthave been carried out, and this, in turn, facilitates comparisons between anthropogenic analogues and modernvitrifi ed wastes.

  • 98.
    Skoglund, Nils
    et al.
    Energy Technology and Thermal Process Chemistry, Umeå University.
    Boström, Dan
    Energy Technology and Thermal Process Chemistry, Umeå University.
    Brännvall, Evelina
    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.
    Grimm, Alejandro
    Öhman, Marcus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Återvinning av fosfor och energi ur avloppsslam genom termisk behandling i fluidiserad bädd; Slutrapport NWI Dp 4, Januari 20132013Report (Other academic)
  • 99.
    Dahlén, Lisa
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Vukicevic, Sanita
    Nordvästra Skånes Renhållnings AB.
    Tapper, Martina
    Nordvästra Skånes Renhållnings AB.
    Återvinning av plast från hushållsavfall: Insamlingsresultat och kvalitet av källsorterad plast2013Report (Other academic)
    Abstract [sv]

    SammanfattningÖvergripande syfte med projektet Återvinning av plast från hushållsavfall var att bidra till ett förbättrat beslutsunderlag vid val av insamlingssystem för plastförpackningar från hushållen.Projektets specifika mål har varit följande: Samla in unika mätdata av felsorteringsgraden i källsorterad plast  Jämföra felsorteringsgraden vid fastighetsnära insamling (FNI) med återvinningsstationer (ÅVS) Kartlägga kommuners informationsinsatser om källsortering Söka samband mellan insamlingsresultat och informationsarbetets utformningProjektet avgränsades till studier i fem svenska kommuner: Gävle, Göteborg, Lund, Lycksele och Söderköping. Plockanalyser gjordes på samlingsprov från fastighetsnära insamling respektive återvinningsstationer i utvalda kommundelar. Huvudsakliga metoder för projektets genomförande har varit provtagning, plockanalyser, intervjuer, litteraturstudier, utvärdering av insamlingsdata och beräkningar. Plockanalyserna genomfördes under åren 2010-2012.Av 75 m3 material (2 800 kg) insamlat från kärl avsedda för återvinning av plastförpackningar, i fem olika kommuner med varierande insamlings-system, var 72 viktprocent rätt sorterade plastförpackningar och 16 viktprocent var plast-produkter utanför producentansvaret. Resterande 12 viktprocent var andra helt felsorterade material, ungefär en tredjedel andra förpackningar och tidningar och i övrigt diverse andra produkter som t.ex. skor, kläder, blöjor, väskor, vaxdukar, matavfall, samt en mindre del el-, elektronik och farligt avfall. Renheten på plasten var bättre från fastighetsnära insamling (10 % icke plast) än från insamling vid återvinningsstationer (15 % icke plast). Renheten var bäst hos villor med fastighetsnära insamling (6,5 % icke plast). Villahush