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  • 1.
    Vestin, Jenny
    et al.
    Swedish Geotechnical Institute (SGI), Sundsvall.
    Nordmark, Desiree
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Arm, Maria
    Swedish Geotechnical Institute (SGI), Linköping.
    Lind, Bo B.
    Swedish Geotechnical Institute (SGI), Göteborg.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Biofuel ash in road stabilization: Lessons learned from six years of field testing2018Ingår i: Transportation Geotechnics, ISSN 2214-3912, Vol. 14, s. 146-156Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In 2009, pulp mill fly ash was used for stabilizing the road base of a low-volume gravel road. Six years after stabilization, a two-year monitoring program and a complementary study were conducted to study the environmental and technical properties of the road and road material. Environmental properties were studied through chemical analysis of road samples by X-ray diffraction (XRF), inductively coupled plasma (ICP) technique and colorimetric techniques. The strength development was studied by falling weight deflectometer (FWD) and compressive strength tests. Potassium (K) and sulphate sulfur (SO4-S) concentrations in road material decreased by 40 and 55%, respectively during this time. Absolute concentrations of most trace elements increased. Leaching of chloride (Cl) salts from road samples decreased with time, while leaching of magnesium (Mg) and calcium (Ca) increased. Leaching of trace elements was below 0.5 mg/kg at all sampling occasions. The bearing capacity increased by 30-50%, and the infiltration capacity decreased compared to a reference section. The results showed that the ash-stabilized sections performed better than conventionally upgraded sections and achieved increased bearing capacity over time. Since the acid neutralizing capacity of the stabilized layer was high and lumps of unreacted ash were still left in the road, it was concluded that the ash material could be utilized once more in a potential end-of-life road recycling.

  • 2.
    Nordmark, Désirée
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Controlling the mobility of chromium and molybdenum in MSWI fly ash in a washing process2018Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 76, s. 727-733Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fly ash from a cogeneration plant near Sundsvall in Sweden was treated in an ash-washing facility. The leaching of chromium (Cr) and molybdenum (Mo) from the ash residue exceeded the limit values for non-hazardous landfills. In this study factors that influence the leaching of Cr and Mo were identified and methods that can reduce the leaching were evaluated. The results revealed that the mobility of Cr and Mo are mainly controlled by pH and redox reactions and sequential extraction tests also showed that the fraction of highly soluble species of Cr and Mo increased after washing due to pH reactions in the ash during the process. Stabilization of the pH at ∼8 through carbonation of the washed ash and a lowering of the redox potential by adding ferrous iron to the process resulted in decreased leaching. Treatment with carbon dioxide yielded a decrease (from 10.7 to 8.2) in the pH and, hence, the leaching of Cr and Mo by 93 and 91%, respectively. And the addition of ferrous iron reduced the leaching of Cr by 50%. Carbonation of the ash can be achieved via treatment with flue gases from the power plant or treatment with landfill gas at the disposal site.

  • 3.
    Marklund, Erik
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Float-sink separation of construction and demolition waste fines2018Ingår i: Detritus, ISSN 2611-4135, Vol. 3, s. 13-18Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Landfilling and waste incineration are two major waste management options. However, due to their carbon content, some wastes may be unsuitable for these systems. Therefore, methods capable of removing organic carbon from wastes should be identified. One of these wastes is represented by construction and demolition fines. In this paper, we investigate the use of water in separating the waste by density, to verify the suitability of this method in the separation of carbon-containing materials, both in lab and field scale tests. The results obtained show that half of the carbon (measured as volatile solids) can be separated. However, this method fails to reliably produce a sink fraction suitable for landfilling, as it continues to be characterized by an excessively high organic material content.

  • 4.
    Marklund, Erik
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Float-sink separation of C&D waste: a case of treatment oriented waste characterization2017Ingår i: Sixteenth International Waste Management and Landfill Symposium: 2 -6 October 2017 S. Margherita di Pula, Cagliari, Italy, Italy, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Landfilling and waste incineration are two major waste management options. However, some wastes can,due to their carbon content,be unsuitable for neither of these systems. Therefore, there is aneed for methods to remove organic carbon from wastes. One of these wastesis the construction and demolition fines. In this paper, we investigate using water for separating the waste by density, to see if this is a suitable method for separating carbon-containingmaterials, both in lab and field scale tests. Results show that halfof the carbon (measured as volatile solids) can be separated. However, this method cannot be said to reliably produce a sink fraction that is suitable for landfilling, as it still contains too much organic materials.

  • 5.
    Nilsson, Mirja
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Effect of accelerated carbonation and zero valent iron on metal leaching from bottom ash2016Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 51, s. 97-104Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    About 85% of the ashes produced in Sweden originated from the incineration of municipal solid waste and biofuel. The rest comes from the thermal treatment of recycled wood, peat, charcoal and others. About 68% of all ashes annually produced in Sweden are used for constructions on landfills, mainly slopes, roads and embankments, and only 3% for construction of roads and working surfaces outside the landfills (SCB, 2013). Since waste bottom ash (BA) often has similar properties to crushed bedrock or gravel, it could be used for road constructions to a larger extent. However, the leaching of e.g. Cr, Cu, Mo, Pb and Zn can cause a threat to the surrounding environment if the material is used as it is. Carbonation is a commonly used pre-treatment method, yet it is not always sufficient.As leaching from aged ash is often controlled by adsorption to iron oxides, increasing the number of Fe oxide sorption sites can be a way to control the leaching of several critical elements. The importance of iron oxides as sorption sites for metals is known from both mineralogical studies of bottom ash and from the remediation of contaminated soil, where iron is used as an amendment.In this study, zero valent iron (Fe(0)) was added prior to accelerated carbonation in order to increase the number of adsorption sites for metals and thereby reduce leaching. Batch, column and pHstat leaching tests were performed and the leaching behaviour was evaluated with multivariate data analysis. It showed that leaching changed distinctly after the tested treatments, in particular after the combined treatment.Especially, the leaching of Cr and Cu clearly decreased as a result of accelerated carbonation. The combination of accelerated carbonation with Fe(0) addition reduced the leaching of Cr and Cu even further and reduced also the leaching of Mo, Zn, Pb and Cd compared to untreated BA. Compared with only accelerated carbonation, the Fe(0) addition significantly reduced the leaching of Cr, Cu and Mo. The effects of Fe(0) addition can be related to binding of the studied elements to newly formed iron oxides. The effects of Fe(0) addition were often more distinct at pH values between 7 and 9, which indicates that a single treatment with only Fe addition would be less effective and a combined treatment is recommended. The pHstat results showed that accelerated carbonation in combination with Fe(0)0 addition widens the pH range for low solubility of about one unit for several of the studied elements. This indicates that pre-treating the bottom ash with a combination of accelerated carbonation and Fe(0) addition makes the leaching properties of the ash less sensitive to pH changes that may occur during reuse. All in all, the addition of Fe0 in combination with carbonation could be an effective pre-treatment method for decreasing the mobility of potentially harmful components in bottom ash.

  • 6.
    Carlsson, My
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik. Veolia Water Technologies AB (AnoxKaldnes), Lund, Sweden.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Morgan-Sagastume, Fernando
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik. Veolia Water Technologies AB (AnoxKaldnes), Lund, Sweden.
    Energy balance performance of municipal wastewater treatment systems considering sludge anaerobic biodegradability and biogas utilisation routes2016Ingår i: Journal of Environmental Chemical Engineering, ISSN 2160-6544, E-ISSN 2213-3437, Vol. 4, nr 4, s. 4680-4689Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The energy balance of a municipal wastewater treatment (WWT) system was evaluated considering the influence of excess biological sludge anaerobic biodegradability (BDAn) and of biogas utilisation as either fuel for co-generation of heat and power (CHP) or for vehicle transport. Sludge thermal pre-treatment prior to anaerobic digestion and high-rate carbon removal were considered as modifications of a reference municipal WWT system to impact the sludge BDAn. Both thermal pre-treatment and a high-rate process with a short sludge retention time (SRT = 1-3d) led to ∼30% higher sludge BDAn than that of untreated sludge from a low-rate WWT system with long SRT ( > 8d), which enhanced methane yields and energy production correspondingly. An efficient separation (40% of CODin) of primary solids promoted biogas production by capturing a significant part of the incoming COD, and lowered aeration energy demands for carbon oxidation due to lower loads of particulate organics into the biological treatment. Thermal pre-treatment can most effectively increase the biodegradability of sludge originating from a low-rate WWT system with a long SRT. Sludge solubilization alone as an indicator of increase biodegradability by a pre-treatment is inadequate for sludge types with inherently high biodegradability. A WWT system with primary separation, sludge pre-treatment, and CHP from biogas can be a net electricity producer and self-sufficient in thermal energy, provided the thermal energy from CHP is available for the pre-treatment. With other types of energy carriers as inputs and outputs, the WWT performance also needs evaluation with respect to the energy economic and environmental value. 

  • 7.
    Brännvall, Evelina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Changes of fly ash properties during the ageing2015Ingår i: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 141, nr 5, artikel-id 4014083Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 8.
    Travar, Igor
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kumpiene, Jurate
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Development of drainage water quality from a landfill cover built with secondary construction materials2015Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 35, s. 148-158Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study was to evaluate the drainage water quality from a landfill cover built with secondary construction materials (SCM), fly ash (FA), bottom ash (BA) sewage sludge, compost and its changes over time. Column tests, physical simulation models and a full scale field test were conducted. While the laboratory tests showed a clear trend for all studied constituents towards reduced concentrations over time, the concentrations in the field fluctuated considerably. The primary contaminants in the drainage water were Cl−, N, dissolved organic matter and Cd, Cu, Ni, Zn with initial concentrations one to three orders of magnitude above the discharge values to the local recipient. Using a sludge/FA mixture in the protection layer resulted in less contaminated drainage water compared to a sludge/BA mixture. If the leaching conditions in the landfill cover change from reduced to oxidized, the release of trace elements from ashes is expected to last about one decade longer while the release of N and organic matter from the sludge can be shortened with about two–three decades. The observed concentration levels and their expected development over time require drainage water treatment for at least three to four decades before the water can be discharged directly to the recipient.

  • 9.
    Carlsson, My
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    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 system2015Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 38, s. 117-125Artikel i tidskrift (Refereegranskat)
    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.

  • 10.
    Carlsson, My
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Importance of food waste pre-treatment efficiency for global warming potential in life cycle assessment of anaerobic digestion systems2015Ingår i: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 102, s. 58-66Artikel i tidskrift (Refereegranskat)
    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

  • 11.
    Lagerkvist, Anders
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Pelkonen, Markku
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Wikström, Tommy
    Quick-start of full-scale anaerobic digestion (AD) using aeration2015Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 38, s. 102-104Artikel i tidskrift (Refereegranskat)
    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.

  • 12.
    Xu, Jingying
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Bravo, Andrea Garcia
    Department of Ecology and Genetics, Limnology, University of Uppsala.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Bertilsson, Stefan
    Department of Ecology and Genetics, Limnology, University of Uppsala.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kumpiene, Jurate
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Sources and remediation techniques for mercury contaminated soil2015Ingår i: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 74, s. 42-53Artikel i tidskrift (Refereegranskat)
    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.

  • 13.
    Lindmark, Johan
    et al.
    School of Business, Society and Engineering, Mälardalen University, Västerås.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Nilsson, Erik
    School of Business, Society and Engineering, Mälardalen University, Västerås.
    Carlsson, My
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    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 Silage2014Ingår i: Applied Biochemistry and Biotechnology, ISSN 0273-2289, E-ISSN 1559-0291, Vol. 174, nr 7, s. 2616-2625Artikel i tidskrift (Refereegranskat)
    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.

  • 14.
    Brännvall, Evelina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Diener, Silvia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Factors influencing chemical and mineralogical changes in RDF fly ashes during aging2014Ingår i: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 140, nr 3, artikel-id 4013014Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 15.
    Nordmark, Desiree
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Vestin, Jenny
    Sveriges Geotekniska Institut.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lind, Bo
    Sveriges Geotekniska Institut.
    Arm, Maria
    Sveriges Geotekniska Institut.
    Hallgren, Per
    Skogsstyrelsen.
    Geochemical Behavior of a Gravel Road Upgraded with Wood Fly Ash2014Ingår i: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 140, nr 10, artikel-id 5014002Artikel i tidskrift (Refereegranskat)
    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

  • 16.
    Andreas, Lale
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Diener, Silvia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Hydraulic performance of a land-fill top cover based on steel slag2014Ingår i: Sardinia 2013: 14th International Waste Management and Landfill Symposium, Forte Village, S. Margherita di Pula (CA), Italy, 30 September - 4 October 2013 ; CD-ROM: Symposium proceedings / [ed] Raffaello Cusso, Cagliari: CISA, Environmental Sanitary Engineering Centre , 2014Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

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

  • 17.
    Nordmark, Desiree
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Industrial By-products used in a Landfill Cover2014Konferensbidrag (Refereegranskat)
    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.

  • 18.
    Xu, Jingying
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Kleja, Dan B
    Swedish Geotechnical Institute.
    Biester, Harald
    Department of Environmental Geochemistry, Institute of Geoecology, University of Braunschweig.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kumpiene, Jurate
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Influence of particle size distribution, organic carbon, pH and chlorides on washing of mercury contaminated soil2014Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 109, s. 99-105Artikel i tidskrift (Refereegranskat)
    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.

  • 19.
    Kumpiene, Jurate
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Brännvall, Evelina
    Luleå tekniska universitet, Verksamhetsstöd. EXTfinansiering.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Project: North Waste Infrastructure2014Övrigt (Övrig (populärvetenskap, debatt, mm))
  • 20.
    Arm, Maria
    et al.
    Statens Geotekniska Institut.
    Vestin, Jenny
    Statens Geotekniska Institut.
    Lind, Bo
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Nordmark, Desiree
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Hallgren, Per
    Skogsstyrelsen.
    Pulp mill fly ash for stabilization of low-volume unpaved forest roads: field performance2014Ingår i: Canadian journal of civil engineering (Print), ISSN 0315-1468, E-ISSN 1208-6029, Vol. 41, nr 11, s. 955-963Artikel i tidskrift (Refereegranskat)
    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.

  • 21.
    Andreas, Lale
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Diener, Silvia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Steel slags in a landfill top cover: Experiences from a full-scale experiment2014Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 34, nr 3, s. 692-701Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 22.
    Bjurström, Henrik
    et al.
    ÅF-Industry AB.
    Lind, B.B.
    Swedish Geotechnical Institute.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Unburned carbon in combustion residues from solid biofuels2014Ingår i: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 117, nr Part A, s. 890-899Artikel i tidskrift (Refereegranskat)
    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.

  • 23.
    Xu, Jingying
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kleja, Dan Berggren
    Department of Environmental Engineering, Swedish Geotechnical Institute.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kumpiene, Jurate
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Influence of soil particle size, organic carbon and pH on mercury distribution and dissolution in contaminated soil2013Ingår i: Influence of soil particle size, organic carbon and pH on mercury distribution and dissolution in contaminated soil, 2013, s. 45-Konferensbidrag (Refereegranskat)
    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.

  • 24.
    Nilsson, Mirja
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Screening analysis of bottom ashes from waste incineration2013Ingår i: Sardinia 2013: 14th International Waste Management and Landfill Symposium, Forte Village, S. Margherita di Pula (CA), Italy, 30 September - 4 October 2013 ; CD-ROM: Symposium proceedings / [ed] Raffaello Cusso, Cagliari: CISA, Environmental Sanitary Engineering Centre , 2013Konferensbidrag (Övrigt vetenskapligt)
    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

  • 25.
    Kumpiene, Jurate
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Desogus, Paolo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Schulenburg, Sven
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    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 tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Utilisation of chemically stabilized arsenic-contaminated soil in a landfill cover2013Ingår i: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 20, nr 12, s. 8649-8662Artikel i tidskrift (Refereegranskat)
    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.

  • 26.
    Lagerkvist, Anders (Redaktör)
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Abstract proceedings of 7th Intercontinental Landfill Research Symposium: Södra Sunderbyn, June 25th to 27th, 20122012Rapport (Övrigt vetenskapligt)
  • 27.
    Nordmark, Desiree
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lindgren, Elisabet
    Sundsvall Energi.
    Vamling, Maria
    Länsstyrelsen Västernorrland.
    Evaluation of methods used to reduce leaching of harmful substances from residual fly ash fraction after washing2012Ingår i: Proceedings of the Thirteenth International Symposium on Environmental Issues and Waste Management in Energy and Mineral Production / [ed] Hao Ge; Carmen Mihaela Neculita; Maria Menegaki; Anil Mehrotra, Irvine, CA, USA: The Reading Matrix Inc. , 2012Konferensbidrag (Refereegranskat)
    Abstract [sv]

    Korstaverken near Sundsvall in Sweden produces electricity and district heating for about 80 000 citizens. Household and commercial wastes are used as fuel in their cogeneration plant. The produced fly ash is treated in an ash washing facility to reduce leaching of hazardous substances. Leaching of chromium and molybdenum from the ash residue exceeds although the limit values for non-hazardous landfills. The aim of this project has been to identify factors that influence the leaching of chromium and molybdenum and how a reduction can be achieved. Reduced mobility can be reached by addition of pH and redox reducing agents, or by carbonation. The results show that there are a number of measures that can generate a washed ash that meets the requirements of non-hazardous landfills. In order to design the optimal full scale solution from a practical and economical perspective, the identified alternatives must be evaluated.

  • 28.
    Wikström, Tommy
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Nordmark, Desiree
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Pelkonen, Markku
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Fluorescent in situ hybridization technique in anaerobic process studies2012Ingår i: Abstract proceedings of 7th Intercontinental Landfill Research Symposium :: Södra Sunderbyn, June 25th to 27th, 2012 / [ed] Anders Lagerkvist, Luleå: Luleå tekniska universitet, 2012, s. 130-131Konferensbidrag (Refereegranskat)
  • 29.
    Andreas, Lale
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Travar, Igor
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Tham, Gustav
    Sweco AB.
    Leaching behaviour of ashes in a landfill cover construction2012Ingår i: Abstract proceedings of 7th Intercontinental Landfill Research Symposium: Södra Sunderbyn, June 25th to 27th, 2012 / [ed] Anders Lagerkvist, Luleå: Luleå tekniska universitet, 2012, s. 39-Konferensbidrag (Refereegranskat)
  • 30.
    Lagerkvist, Anders
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Dahlén, Lisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Solid Waste Generation and Characterization2012Ingår i: Encyclopedia of Sustainability Science and Technology, New York: Encyclopedia of Global Archaeology/Springer Verlag, 2012, s. 10000-10013Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Waste is generated in all processes. According to the laws of thermodynamics , materials and energy can be transformed but never destroyed. Even if material is substantially transformed, all matter which is introduced in any kind of process will come out of the process in exactly the same number of kilograms, either as products, by-products , or waste. Waste may be solid, liquid, or gaseous. In many cases, gaseous waste is a dominating outflow when processing solid matter. However, the focus in this article is on solid waste.Waste is often perceived as the remains from consumption. However, the major part of all solid waste is generated already by consumers' demand for products, i.e., before the products were consumed and thrown away. In general, the extraction of natural resources and industrial production processes produce massively more solid waste than the consumer products amount to, e.g., about 20 times according to European waste data [14]. As material flows through society, waste is formed in each step, as illustrated in Fig. 1. The material wastes can either end up in landfills or they can be dispersed in water, air, or soil. The dispersion in liquid phases typically exits the material from the waste management domain and turns it into pollution, albeit solid wastes can also form pollution, such as the floating plastic of the oceans.

  • 31.
    Carlsson, My
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Morgan-Sagastume, Fernando
    AnoxKaldnes AB.
    The effects of substrate pre-treatment on anaerobic digestion systems: a review2012Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 32, nr 9, s. 1634-1650Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Focus is placed on substrate pre-treatment in anaerobic digestion (AD) as a means of increasing biogas yields using today’s diversified substrate sources. Current pre-treatment methods to improve AD are being examined with regard to their effects on different substrate types, highlighting approaches and associated challenges in evaluating substrate pre-treatment in AD systems and its influence on the overall system of evaluation. WWTP residues represent the substrate type that is most frequently assessed in pre-treatment studies, followed by energy crops/harvesting residues, organic fraction of municipal solid waste, organic waste from food industry and manure. The pre-treatment effects are complex and generally linked to substrate characteristics and pre-treatment mechanisms. Overall, substrates containing lignin or bacterial cells appear to be the most amendable to pre-treatment for enhancing AD. Approaches used to evaluate AD enhancement in different systems is further reviewed and challenges and opportunities for improved evaluations are identified.

  • 32.
    Brännvall, Evelina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Travar, Igor
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kumpiene, Jurate
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ageing of ashes in a landfill top cover2011Ingår i: SARDINIA 2011: Thirteenth International Waste Management and Landfill Symposium, S. Margherita di Pula, Cagliari, Italy; 3 - 7 October 2011 / [ed] Raffaello Cossu, Cagliari: CISA Publisher, Italy , 2011Konferensbidrag (Refereegranskat)
    Abstract [en]

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

  • 33.
    Kumpiene, Jurate
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Robinson, Ryan
    Brännvall, Evelina
    Nordmark, Desiree
    Bjurstöm, Henrik
    ÅF-Engineering AB.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Ecke, Holger
    Carbon speciation in ash, residual waste and contaminated soil by thermal and chemical analyses2011Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 31, nr 1, s. 18-25Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Carbon in waste can occur as inorganic (IC), organic (OC) and elemental carbon (EC) each having distinct chemical properties and possible environmental effects. In this study, carbon speciation was performed using thermogravimetric analysis (TGA), chemical degradation tests and the standard total organic carbon (TOC) measurement procedures in three types of waste materials (bottom ash, residual waste and contaminated soil). Over 50% of the total carbon (TC) in all studied materials (72% in ash and residual waste, and 59% in soil) was biologically non-reactive or EC as determined by thermogravimetric analyses. The speciation of TOC by chemical degradation also showed a presence of a non-degradable C fraction in all materials (60% of TOC in ash, 30% in residual waste and 13% in soil), though in smaller amounts than those determined by TGA. In principle, chemical degradation method can give an indication of the presence of potentially inert C in various waste materials, while TGA is a more precise technique for C speciation, given that waste-specific method adjustments are made. The standard TOC measurement yields exaggerated estimates of organic carbon and may therefore overestimate the potential environmental impacts (e.g. landfill gas generation) of waste materials in a landfill environment.

  • 34.
    Vestin, Jenny
    et al.
    Statens Geotekniska Institut.
    Arm, Maria
    Statens Geotekniska Institut.
    Nordmark, Desiree
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Hallgren, Per
    Skogsstyrelsen.
    Tiberg, Charlotta
    Statens Geotekniska Institut.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lind, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Effektivt askutnyttjande i vägar2011Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Två provsträckor, uppgraderade med olika mängd aska, utvärderades med avseende på ask-grusblandningens homogenitet och skillnader mellan de båda sträckorna. Askgrusblandningens homogenitet varierade i vägen även om den förväntade askhalten uppnåddes i medeltal. Packningsgraden blev lägre än förväntat vilket visar på vikten av omsorgsfull vattning och packning. Provsträckan med störst askhalt hade högst styvhet.

  • 35.
    Nordmark, Desiree
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Vestin, Jenny
    Sveriges Geotekniska Institut.
    Arm, Maria
    Sveriges Geotekniska Institut.
    Lind, Bo
    Sveriges Geotekniska Institut.
    Hallgren, Per
    Skogsstyrelsen.
    Environmental and mechanical assessment of wood fly ash used for stabilisation of gravel roads2011Ingår i: SARDINIA 2011: Thirteenth International Waste Management and Landfill Symposium; [3 - 7 October 2011, S. Margherita di Pula - Cagliari, Sardinia, Italy] ; CD-ROM: Proceedings / [ed] Raffaello Cossu, Cagliari: CISA Publisher, Italy , 2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    Due to climate change, there is a growing demand for mechanically stabilising forestry roads in Sweden. One way to do this is by addition of cement to the bearing layer of the road. In this study, cement was replaced by a forestry industry fly ash. Mechanical testing showed that a good stabilising effect could be achieved and at a 30% ash addition, it could resist more than 12 freeze-thaw cycles. The environmental impact of the ash addition was assessed using a standard leaching test at a liquid to solid ration of ten. The results indicated that most constituents of the ash remained fairly stable, but that notably chloride, potassium, calcium and sodium was mobilised in the grams per kg of TS range, adding up to about 1 % of the total mass. This may cause an elevated salinity in the emediate vicinity of a road, e g in the ditches, under a short time period, but is not considered to be a major problem for recipients. The results also indicate that the total content is a poor estimate for the leachability of various elements.

  • 36. Nordmark, Desiree
    et al.
    Kumpiene, Jurate
    Andreas, Lale
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Mobility and fractionation of arsenic, chromium and copper in thermally treated soil2011Ingår i: Waste Management & Research, ISSN 0734-242X, E-ISSN 1096-3669, Vol. 29, nr 1, s. 3-12Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Thermal treatment is used to remediate soil co-contaminated with organic and inorganic contaminants. It destroys organic contaminants, but the remaining inorganic contaminants require further treatment. In this study the effects of thermal treatment on the mobility, speciation and chemical fractionation of As, Cr and Cu in a CCA-polluted soil were evaluated by leaching tests, As speciation assays and a sequential extraction procedure. The soil was sieved into four size fractions (<0.125, 0.125—0.250, 0.250—0.500 and 0.500—1.0 mm), each of which was treated at 800°C and analysed in comparison with the untreated soil. The leaching of As and Cr increased by factors of 18—40 and 2—23, respectively, while the mobility of Cu decreased 12—14-fold after treatment. The concentration of As(V) in pore water of the finest soil fraction increased 19-fold, whereas that of As(III) remained constant. The treatment reduced As, Cr and Cu associated with the reducible soil fraction. In addition, it increased the proportions of As and Cr (slightly) associated with the exchangeable and acid-soluble soil fractions, and the proportions of Cu and Cr (substantially) associated with the residual fraction.

  • 37.
    Windt, Laurent De
    et al.
    Ecole des Mines de Paris.
    Dabo, David
    Ecole des Mines de Paris.
    Lidelöw, Sofia
    Badreddine, Rabia
    INERIS, Wastes and Contaminated Sites Unit.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    MSWI bottom ash used as basement at two pilot-scale roads: comparison of leachate chemistry and reactive transport modeling2011Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 31, nr 2, s. 267-280Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The recycling of municipal solid waste incineration bottom ash as aggregates for road basement requires assessing the long-term evolution of leachate chemistry. The Dåva (Sweden) and Hérouville (France) pilot-scale roads were monitored during 6 and 10 years, respectively. Calculated saturation indices were combined to batch test modeling to set a simplified geochemical model of the bottom ash materials. A common reactive transport model was then applied to both sites. At Hérouville, pH and the concentration of most elements quickly drop during the first two years to reach a set of minimum values over 10 years. The decrease is less pronounced at Dåva. The evolutions of pH and major element concentrations are fairly well related to the following pH-buffering sequence: portlandite, C-S-H phases or pseudo-wollastonite and, finally, calcite in equilibrium with atmospheric CO2. Al(OH)3, barite, ettringite and monohydrocalcite may also control leachate chemistry. Cu release is correctly modeled by DOM complexation and tenorite equilibrium. Temperature has no significant effect on the modeling of leachate chemistry in the range 5-30 °C, except at high pH. Effects at road edges and roadside slopes are important for the release of the less reactive elements and, possibly, for carbonation processes.

  • 38. Tan, Zhongxin
    et al.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Phosphorus recovery from the biomass ash: a review2011Ingår i: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 15, nr 8, s. 3588-3602Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Biomass ash, generated during the thermal chemical conversion of biomass for energy production, is an industrial by-product which is often recognized as a solid waste, but there are some useful elements in the biomass ash such as phosphorus, etc. So through some technology and methods, the biomass ash can be transferred into a useful resource. The paper mainly includes the following aspects: biomass ash composition characteristics, biomass thermal chemical conversion for phosphorus and phosphorus recovery technology from biomass ash. Through these aspects literature review, not only the whole biomass ash characteristics was made clear, but also we think that the idea of phosphorus from biomass ash is feasible, especially for some high phosphorus ash such as sludge ash, meat and bone meal (MBM) ash, etc. So the review about phosphorus from the biomass ash is very important practical significance for biomass energy, biomass ash disposal and phosphorus resource.

  • 39.
    Nordmark, Desiree
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lindgren, Elisabet
    Sundsvall Energi.
    Vamling, Maria
    Sundsvall Energi.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Processoptimering av asktvätt2011Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Asktvätten vid Korstaverket i Sundsvall producerar en tvättad aska som består av en blandning av fallande flygaska och vattenreningsslam. I tvätten avskiljs framför allt lättlösliga salter och en mobil fraktion av andra ämnen. De senare avskiljs till större delen i den efterföljande vattenreningen vars slam blandas med fallande aska i tvätten. Blandningen klarar krav för deponiklass II med undantag för utlakning av krom och molybden, för vilka dispens har erhållits upp till tre gånger gränsvärdet, som är 10 mg/kg TS. I här rapporterat projekt har syftet varit att identifiera de faktorer som påverkar främst kroms och molybdens mobilitet i den tvättade askan (dvs flygaska + slam) och hur den kan påverkas praktiskt. Resultaten kan vara av intresse för dem som söker alternativ för askhantering. I Sverige har ingen motsvarande undersökning utförts tidigare. Molybden och andra grundämnen som bildar oxyanjoner tenderar att bli mer mobila vid högre pH-värden och därför kan tillsatser till asktvätt och reningsprocess som sänker pH mot neutrala värden ge en lägre utlakning. I synnerhet molybden mobiliseras ur reningsslammet vid kontakt med den mera basiska askan, och därför kan en separat deponering av tvättad aska och slam vara ett sätt att minska den totala utlakningen. För att reducera Cr6+ till trevärd krom och därmed minska kroms mobilitet, har tillsatser av elementärt och tvåvärt järn används. Tvåvärt järn har även testats i full skala under en kort tid. I lab har både elementärt järn och tvåvärt järn visat sig ge tydligt lägre kromlakning, elementärt järn var effektivast. I full skala användes tvåvärt järn, men resultatet var inte entydigt. Här kan det tänkas att järnskrot från bottenaska skulle kunna användas. Den effektivaste tillsatsen, som dock bara testats i lab var koldioxid, tillsatsen reducerade både krom- och molybdenutlakningen. Här kan man tänka sig att använda koldioxid från förbränningsanläggningen, eller driva en efterbehandling med deponigas. Våra resultat visar att det genom olika åtgärder, eller kombinationer av åtgärder, går att producera en tvättad aska som väl uppfyller de krav på utlakning som används för en klass II deponi idag. Därmed är projektets mål uppnådda. För att utforma den praktiskt och ekonomiskt mest optimala lösningen behöver de identifierade alternativen utvärderas.

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

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

  • 41. Diener, Silvia
    et al.
    Andreas, Lale
    Brännvall, Evelina
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Evaluation and discussion of steel slag mineralogy after ageing under laboratory and field conditions2010Ingår i: The 6th Intercontinental Landfill research Symposium, 2010, s. 107-109Konferensbidrag (Övrigt vetenskapligt)
  • 42. Dahlén, Lisa
    et al.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Evaluation of recycling programmes in household waste collection systems2010Ingår i: Waste Management & Research, ISSN 0734-242X, E-ISSN 1096-3669, Vol. 28, nr 7, s. 577-586Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A case study and a literature review have been carried out to address the two questions: how can waste flow data from collection systems be interpreted and compared? and which factors are decisive in the results of recycling programmes in household waste collection systems? The aim is to contribute to the understanding of how recycling programmes affect the quantity of waste and sorting activities. It is shown how the results from various waste sorting systems can be interpreted and made comparable. A set of waste flow indicators is proposed, which together with generic system descriptions can facilitate comparisons of different collections systems. The evaluation of collection systems depends on the system boundaries and will always be site-specific to some degree. Various factors are relevant, e.g. environmental objectives, technical function, operating costs, types of recyclable materials collected separately, property-close collection or drop-off systems, economic incentives, information strategies, residential structure, social codes, etc. Kerbside collection of recyclables and weight-based billing led to increased waste sorting activities in the case study. Forty-three decisive factors are listed and discussed.

  • 43. Brännvall, Evelina
    et al.
    Andreas, Lale
    Diener, Silvia
    Tham, Gustav
    Telge AB.
    Sjöblom, Rolf
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Formation of secondary mineral phases during the ageing of RDF fly ashes2010Ingår i: The 6th Intercontinental Landfill Research Symposium, 2010, s. 110-112Konferensbidrag (Övrigt vetenskapligt)
  • 44. Dahlén, Lisa
    et al.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Pay as you throw: strengths and weaknesses of weight-based billing in household waste collection systems in Sweden2010Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 30, nr 1, s. 23-31Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Householders' response to weight-based billing for the collection of household waste was investigated with the aim of providing decision support for waste management policies. Three questions were addressed: How much and what kind of information on weight-based billing is discernible in generic Swedish waste collection statistics? Why do local authorities implement weight-based billing, and how do they perceive the results? and, Which strengths and weaknesses of weight-based billing have been observed on the local level? The study showed that municipalities with pay-by-weight schemes collected 20% less household waste per capita than other municipalities. Surprisingly, no part of this difference could be explained by higher recycling rates. Nevertheless, the majority of waste management professionals were convinced that recycling had increased as a result of the billing system. A number of contradicting strengths and weaknesses of weight-based billing were revealed.

  • 45.
    Travar, Igor
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lidelöw, Sofia
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Tham, Gustav
    Telge Återvinning AB.
    Lagerkvist, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Assessing the environmental impact of ashes used in a landfill cover construction2009Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 29, nr 4, s. 1336-1346Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Large amounts of construction materials will be needed in Europe in anticipation for capping landfills that will be closed due to the tightening up of landfill legislation. This study was conducted to assess the potential environmental impacts of using refuse derived fuel (RDF) and municipal solid waste incineration (MSWI) ashes as substitutes for natural materials in landfill cover designs. The leaching of substances from a full-scale landfill cover test area built with different fly and bottom ashes was evaluated based on laboratory tests and field monitoring. The water that drained off above the liner (drainage) and the water that percolated through the liner into the landfill (leachate) were contaminated with Cl-, nitrogen and several trace elements (e.g., As, Cu, Mo, Ni and Se). The drainage from layers containing ash will probably require pre-treatment before discharge. The leachate quality from the ash cover is expected to have a minor influence on overall landfill leachate quality because the amounts generated from the ash covers were low, <3-30 l (m2 yr)-1. Geochemical modelling indicated that precipitation of clay minerals and other secondary compounds in the ash liner was possible within 3 years after construction, which could contribute to the retention of trace elements in the liner in the long term. Hence, from an environmental view point, the placement of ashes in layers above the liner is more critical than within the liner.

  • 46.
    Nordmark, Desiree
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rönkkö, Reima
    University of Oulu.
    Kumpiene, Jurate
    Andreas, Lale
    Lagerkvist, Anders
    Changes in leaching and chemical fractionation of arsenic, chromium and copper in soil after thermal treatment2009Ingår i: SARDINIA 2009: Twelfth International Waste Management and Landfill Symposium ; [5 - 9 October 2009, S. Margherita di Pula, Cagliari, Sardinia, Italy] / [ed] Raffaello Cossu, Cagliari: CISA, Environmental Sanitary Engineering Centre , 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    Thermal treatment is used for remediation of soils contaminated with both organic and inorganic contaminants. The target is destruction of organic contaminants while the residue containing the inorganic contaminants has to be further treated. The effects of thermal treatment on As, Cr and Cu in contaminated soil are evaluated in laboratory and field tests, using leaching test, As speciation and sequential extraction test. In laboratory tests on four particle size fractions, the leaching of As and Cr increased by factors of 18-40 and 2-23, respectively, while the mobility of Cu decreased 12-4 fold after thermal treatment. The concentration of As(V) in the finest soil fraction increased 19 fold, while As(III) remained constant. Arsenic, Cr and Cu associated to the reducible soil fraction decreased, possibly due to enhanced crystallisation of Fe oxides and reduction of available adsorption sites. In the field test, the concentration of As, Cr and Cu was 1-4 times higher in the filter fraction compared to the treated soil.

  • 47.
    Travar, Igor
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lidelöw, Sofia
    Tham, Gustav
    Telge AB.
    Lagerkvist, Anders
    Development of drainage water quality from landfill covers built with ashes and sewage sludge2009Ingår i: SARDINIA 2009: Twelfth International Waste Management and Landfill Symposium ; [5 - 9 October 2009, S. Margherita di Pula, Cagliari, Sardinia, Italy] / [ed] Raffaello Cossu, Cagliari: CISA, Environmental Sanitary Engineering Centre , 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    An alternative to virgin and artificial materials in landfill cover can be various types of waste materials like ashes and sewage sludge. From the environmental point of view, the most interesting question to study is the quality of the drainage water generated above the liner in landfill cover built with waste materials. Thus, the main aim of this paper is the evaluation of drainage water quality and time required for its treatment. Results from a full scale test, physical models and a column test were used in the evaluation of the drainage water quality development. The main contaminants identified in drainage water were N-tot, As, Cu, Cd, Pb, Zn and Ni. The laboratory tests showed higher concentrations of N-tot, NH4-N, TOC, As and Pb, but lower values of Cl, Zn, Ba and Ni in comparison with drainage water from the field.  It was probably a result of different factors that may have influence on leaching but interactions of the protection layer with the vegetation layer and the liner surface are expected to influence the results from the field. According to results from the laboratory experiments, drainage water will probably need treat­ment for at least two-three decades after covering.

  • 48.
    Asplund, Erik
    et al.
    inno Scandinavia AB.
    Lagerkvist, Anders
    Heydebreck, Peter
    inno AG.
    Dahlén, Lisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Norberg, Anna
    Umeå universitet.
    Framsyn för Norrbotten och Västerbotten: en idéskrift om utvecklingsinsatser idag och imorgon2009Rapport (Övrigt vetenskapligt)
    Abstract [sv]

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

  • 49.
    Herrmann, Inga
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Svensson, Malin
    Ecke, Holger
    Kumpiene, Jurate
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Maurice, Christian
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andreas, Lale
    Lagerkvist, Anders
    Hydraulic conductivity of fly ash: sewage sludge mixes for use in landfill cover liners2009Ingår i: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 43, nr 14, s. 3541-3547Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Secondary materials could help meeting the increasing demand of landfill cover liner materials. In this study, the effect of compaction energy, water content, ash ratio, freezing, drying and biological activity on the hydraulic conductivity of two fly ash - sewage sludge mixes was investigated using a 27-1 fractional factorial design. The aim was to identify the factors that influence hydraulic conductivity, to quantify their effects and to assess how a sufficiently low hydraulic conductivity can be achieved. The factors compaction energy and drying, as well as the factor interactions material×ash ratio and ash ratio×compaction energy affected hydraulic conductivity significantly (α = 0.05). Freezing on 5 freeze-thaw cycles did not affect hydraulic conductivity. Water content affected hydraulic conductivity only initially. The hydraulic conductivity data were modelled using multiple linear regression. The derived models were reliable as indicated by R2adjusted values between 0.75 and 0.86. Independent on the ash ratio and the material, hydraulic conductivity was predicted to be between 1.7 × 10-11 m s-1 and 8.9 × 10-10 m s-1 if the compaction energy was 2.4 J cm-3, the ash ratio between 20 and 75 % and drying did not occur. Thus, the investigated materials met the limit value for non-hazardous waste landfills of 10-9 m s-1.

  • 50.
    Dahlén, Lisa
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Åberg, Helena
    Department of Food, Health and Environment, University of Gothenburg.
    Lagerkvist, Anders
    Berg, Per E.O.
    HB Anttilator, Stagnellsgatan 3, SE, 652 23, Karlstad.
    Inconsistent pathways of household waste2009Ingår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 29, nr 6, s. 1798-1806Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this study was to provide policy-makers and waste management planners with information about how recycling programs affect the quantities of specific materials recycled and disposed of. Two questions were addressed: which factors influence household waste generation and pathways? and how reliable are official waste data? Household waste flows were studied in 35 Swedish municipalities, and a wide variation in the amount of waste per capita was observed. When evaluating the effect of different waste collection policies, it was found to be important to identify site-specific factors influencing waste generation. Eleven municipal variables were investigated in an attempt to explain the variation. The amount of household waste per resident was higher in populous municipalities and when net commuting was positive. Property-close collection of dry recyclables led to increased delivery of sorted metal, plastic and paper packaging. No difference was seen in the amount of separated recyclables per capita when weight-based billing for the collection of residual waste was applied, but the amount of residual waste was lower. Sixteen sources of error in official waste statistics were identified and the results of the study emphasize the importance of reliable waste generation and composition data to underpin waste management policies.

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