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  • 301.
    Flanagan, Kelsey
    et al.
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 Avenue Blaise Pascal, Cité Descartes, 77455, Marne-la-Vallée Cedex 2, France.
    Branchu, Philippe
    CEREMA, 12 Rue Léon Teisserenc de Bort, 78190, Trappes, France.
    Boudahmane, Lila
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 Avenue Blaise Pascal, Cité Descartes, 77455, Marne-la-Vallée Cedex 2, France.
    Caupos, Emilie
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 Avenue Blaise Pascal, Cité Descartes, 77455, Marne-la-Vallée Cedex 2, France.
    Demare, Dominique
    IFSTTAR, Laboratoire Eau et Environnement, Route de Bouaye CS4, 44344, Bouguenais Cedex, France.
    Deshayes, Steven
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 Avenue Blaise Pascal, Cité Descartes, 77455, Marne-la-Vallée Cedex 2, France.
    Dubois, Philippe
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 Avenue Blaise Pascal, Cité Descartes, 77455, Marne-la-Vallée Cedex 2, France.
    Meffray, Laurent
    CEREMA, 12 Rue Léon Teisserenc de Bort, 78190, Trappes, France.
    Partibane, Chandirane
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 Avenue Blaise Pascal, Cité Descartes, 77455, Marne-la-Vallée Cedex 2, France.
    Saad, Mohamed
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 Avenue Blaise Pascal, Cité Descartes, 77455, Marne-la-Vallée Cedex 2, France.
    Gromaire, Marie-Christine
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 Avenue Blaise Pascal, Cité Descartes, 77455, Marne-la-Vallée Cedex 2, France.
    Field performance of two biofiltration systems treating micropollutants from road runoff2018In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 145, p. 562-578, article id S0043-1354(18)30694-8Article in journal (Refereed)
    Abstract [en]

    The treatment efficiency of a vegetative filter strip and a biofiltration swale treating heavily loaded road runoff are evaluated. Concentrations measured in water drained from the two systems are compared to those in untreated road runoff collected from a reference catchment for a wide range of contaminants including organic carbon, nutrients (N and P), trace metals, and organic micropollutants (polycyclic aromatic hydrocarbons (PAH), total petroleum hydrocarbons (TPH), alkylphenols, bisphenol-A, phthalates), in both total and dissolved phases. Predominantly particulate pollutants, including Pb, Zn and PAH, were very efficiently removed (around 90%) for most events. However, poor particulate removal was observed during a winter period. Relatively few pollutants were significantly removed in the dissolved phase and observed concentration reductions tended to be lower than those of suspended solids and associated pollutants; as such, lower removals were observed for total concentrations of moderately particulate micropollutants, including bisphenol-A, alkylphenols and phthalates. In addition, some pollutants appear to be emitted from various biofilter components (filter media, drainage and lining materials), as low or negative concentration removals were observed during the first months of operation of the biofiltration swale.

  • 302.
    Flanagan, Kelsey
    et al.
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 avenue Blaise Pascal, Cité Descartes, 77455 Marne-la-Vallée Cedex 2, France.
    Branchu, Philippe
    Cerema, 12 Rue Léon Teisserenc de Bort, 78190 Trappes, France.
    Boudahmane, Lila
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 avenue Blaise Pascal, Cité Descartes, 77455 Marne-la-Vallée Cedex 2, France.
    Caupos, Emilie
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 avenue Blaise Pascal, Cité Descartes, 77455 Marne-la-Vallée Cedex 2, France.
    Demare, Dominique
    IFSTTAR, Laboratoire Eau et Environnement, route de Bouaye CS4, 44344 Bouguenais Cedex, France.
    Deshayes, Steven
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 avenue Blaise Pascal, Cité Descartes, 77455 Marne-la-Vallée Cedex 2, France.
    Dubois, Philippe
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 avenue Blaise Pascal, Cité Descartes, 77455 Marne-la-Vallée Cedex 2, France.
    Meffray, Laurent
    Cerema, 12 Rue Léon Teisserenc de Bort, 78190 Trappes, France.
    Partibane, Chandirane
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 avenue Blaise Pascal, Cité Descartes, 77455 Marne-la-Vallée Cedex 2, France.
    Saad, Mohamed
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 avenue Blaise Pascal, Cité Descartes, 77455 Marne-la-Vallée Cedex 2, France.
    Gromaire, Marie-Christine
    LEESU, UMR MA 102, École des Ponts, AgroParisTech, UPEC, UPE, Champs-sur-Marne, 6-8 avenue Blaise Pascal, Cité Descartes, 77455 Marne-la-Vallée Cedex 2, France.
    Retention and transport processes of particulate and dissolved micropollutants in stormwater biofilters treating road runoff.2019In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 656, p. 1178-1190, article id S0048-9697(18)34660-6Article in journal (Refereed)
    Abstract [en]

    Road runoff is contaminated by various micropollutants and may be treated using low impact development techniques, such as stormwater biofilters. Better understanding the processes, such as filtration, sorption and leaching, which affect pollutants in these systems is essential to reliably predicting treatment performance and optimizing system design. Field data from an in situ monitoring campaign, wherein dissolved and particulate concentrations of a wide range of micropollutants (trace metals, polycyclic aromatic hydrocarbons, bisphenol-A, alkylphenols and phthalates) were characterized in untreated road runoff and biofilter outlets for 19 rain events, are used to explore transport and retention processes. Although retention of the particulate phase of pollutants was generally quite effective, unusually high particle concentrations were observed at biofilter outlets for three winter events. Particle characterization in road runoff and outlet waters revealed that this degraded performance was due to poor filtration rather than particle erosion, which was attributed to the relative abundance of small (<10 μm) particles during this period, along with possible preferential flows. Dissolved pollutants were less effectively removed in general. To better understand this behavior, field results were combined with laboratory sorption and leaching tests. Dissolved concentrations of trace metals were shown to be influenced by organic carbon; leaching from road-originated particles may also influence their transport. Removal of the dissolved phase of organic micropollutants was limited by the contamination of the filter media, either before installation or during the first period of operation, due to emissions from construction materials.

  • 303.
    Flanagan, Kelsey
    et al.
    Laboratoire Eau, Environnement et Systèmes Urbains, Université de Paris-Est – Ecole des Ponts Paris-Tech, 6-8 avenue Blaise Pascal, Cité Descartes, Champs-sur-Marne, 77455 Marne-la-Vallée Cedex 2, France.
    Branchu, Philippe
    Cerema/DTer Ile-de-France, 12 rue Teisserenc de Bort, 78190 Trappes, France.
    Ramier, David
    erema/DTer Ile-de-France, 12 rue Teisserenc de Bort, 78190 Trappes, France.
    Gromaire, Marie-Christine
    Laboratoire Eau, Environnement et Systèmes Urbains, Université de Paris-Est – Ecole des Ponts Paris-Tech, 6-8 avenue Blaise Pascal, Cité Descartes, Champs-sur-Marne, 77455 Marne-la-Vallée Cedex 2, France.
    Evaluation of the relative roles of a vegetative filter strip and a biofiltration swale in a treatment train for road runoff.2017In: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 75, no 3-4, p. 987-997Article in journal (Refereed)
    Abstract [en]

    In order to determine the relative importance of a vegetative filter strip and a biofiltration swale in a treatment train for road runoff, US EPA Storm Water Management Model was used to model infiltration and runoff from the filter strip. The model consisted of a series of subcatchments representing the road, the filter strip and the side-slopes of the swale. Simulations were carried out for different rain scenarios representing a variety of climatic conditions. In addition, a sensitivity analysis was conducted for the model's different parameters (soil characteristics and initial humidity, roughness, geometry, etc.). This exercise showed that for the system studied, the majority of road runoff is treated by the filter strip rather than the biofiltration swale, an effect observed especially during periods of low-intensity rainfall. Additionally, it was observed that the combination of infiltration of road runoff in the filter strip and direct rainfall on the system leads to a significant and variable dilution of the runoff reaching the swale. This result has important implications for evaluating the treatment efficiency of the system.

  • 304.
    Foorginezhad, Sahar
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Yu, Gangqiang
    Faculty of Environment and Life, Beijing University of Technology, Beijing, China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Reviewing and screening ionic liquids and deep eutectic solvents for effective CO2 capture2022In: Frontiers in Chemistry, E-ISSN 2296-2646, Vol. 10, article id 951951Article, review/survey (Refereed)
    Abstract [en]

    CO2 capture is essential for both mitigating CO2 emissions and purifying/conditioning gases for fuel and chemical production. To further improve the process performance with low environmental impacts, different strategies have been proposed, where developing liquid green absorbent for capturing CO2 is one of the effective options. Ionic liquids (IL)/deep eutectic solvents (DES) have recently emerged as green absorbents with unique properties, especially DESs also benefit from facile synthesis, low toxicity, and high biodegradability. To promote their development, this work summarized the recent research progress on ILs/DESs developed for CO2 capture from the aspects of those physical- and chemical-based, and COSMO-RS was combined to predict the properties that are unavailable from published articles in order to evaluate their performance based on the key properties for different IL/DES-based technologies. Finally, top 10 ILs/DESs were listed based on the corresponding criteria. The shared information will provide insight into screening and further developing IL/DES-based technologies for CO2 capture.

  • 305.
    Forsberg, E.
    et al.
    Luleå University of Technology.
    Andreason, B.
    Stabilization Of Milling Wastes For Construction1977In: CIM bulletin, ISSN 0317-0926, E-ISSN 1718-4169, Vol. 70, no 779, p. 74-74Article in journal (Other academic)
  • 306.
    Forsberg, Jonas
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Energy transition in transportation: Applying TIMES-based energy system optimisation models to sub-national levels2021Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Transportation is embedded in the fabric of society and a key enabler of socio-economic development, but it is also a major source of carbon dioxide (CO2) and local air pollution (AP). Cities collectively account for around three quarters of total energy-related CO2 emissions, and the negative health impacts from local APs are most felt in dense urban environments. Thus, transitioning away from current fossil fuel regime in urban transportation is necessary to address both global and local challenges. Mathematical models as energy system optimisation models (ESOMs) are commonly applied to explore contrasting energy futures and to provide insights on how the energy system (or specific sub-sectors) may evolve under different conditions. However, ‘typical’ national level models are not fully adapted to capture the characteristics of local (city) transportation, and previous city-level ESOM based analyses have focused on decarbonisation of local energy systems, thus omitting other local policy considerations as e.g. air quality, and several studies excluded transportation altogether. 

    In this thesis, a generic city-level ESOM framework (TIMES-City) was further adapted and used to provide policy-relevant insights on the anticipated energy transition of the local transport sector. The underlying work rests on a systems analysis approach, building on careful consideration of the overall system performance and boundaries, understanding of specific system characteristics, and challenges and opportunities facing local ‘system managers’; this has implications for model representation and for quantitative and qualitative modelling assumptions. Further, availability and quality of local transport, energy and emission data needed to calibrate models poses significant challenges, and considerable effort was also put on producing projections for future transport demand (a key model input), using lessons and input data from traditional transport demand models. These considerations were addressed in Paper I. 

    The model was then applied to two different cases (in Sweden) to explore potential conflicts and co-benefits between ambitious climate targets and deep cuts in APs (Paper II), and to assess the roles of local and regional governments in CO2 mitigation when also considering ambitious national-scale policies (Paper III). The results of Paper II indicate that substituting fossil fuels for biofuels in conventional vehicles is the least-cost decarbonisation pathway, however this produces only minor or even negative benefits to air quality. While, zero-emission vehicles cut all local tail-pipe emissions, but their total impact on climate change mitigation is determined by upstream impacts from the conversion and distribution of energy carriers. Thus, ensuring low levels of total CO2 and APs from transportation calls for re-coupling of the local and global responsibilities and motivations into comprehensive mitigation strategies. The results of Paper III indicate that current Swedish national mitigation measures will drive down CO2 emissions in transportation considerably, but biofuel availability and BEV (battery electric vehicles) costs are critical for the rate and extent of the transition, while locally and regionally determined measures to enable shifts (from car) to active travelling, public transportation and home-based work have a much more limited direct impact. Nonetheless, these measures, along with city investments in BEVs and charging infrastructure which pave the way also for residents and local businesses, can help to reduce overall energy intensity of the transport sector, thus slowing down growth in fuel demand and contribute to reaching ambitious climate targets with limited renewable resources (as e.g. biofuels). The two studies (Papers II and III) illustrate the usefulness of applying comprehensive ESOMs also at sub-national levels, providing insights on both global and local sustainability implications as well as deeper understanding of the roles of local and regional decision-makers in enabling and supporting low-carbon transitions in transportation. 

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  • 307.
    Forsberg, Jonas
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    On the road to climate neutral Swedish transportation: Energy system modelling to support the transition at national, regional, and local levels2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Transportation is a critical pillar of modern society. Over the past decades, growth in mobility of people and goods have been both enabled by and dependent upon fossil fuels. Strong action is needed to break this dependence in order to reduce CO2. The overall aim of this thesis is to support the transition towards climate neutral transportation in Sweden considering local, regional, and national settings, by use of TIMES-based ESOMs. This is addressed by i) developing and adapting transport sector representation in TIMES models considering context specific conditions and preferences, ii) applying the models to define and explore alternative long-term scenarios that meet the overall goals, iii) and identify key measures and policy implications for achieving climate neutral transportation.

    In Paper I (Local setting) key considerations and requirements in respect of modelling local energy transition of transportation in a TIMES energy system modelling framework was outlined. The model was then applied to address potential trade-offs between global climate concerns and local air quality issues (Paper II – Local setting). The results showed that decarbonisation with biofuels does little to enhance local air quality, while zero-emission vehicles – that eliminate all local tailpipe emissions – can induce significant upstream CO2 emissions (from energy supply sectors). Comprehensive multi-level strategies are needed to drastically reduce both CO2 and local air pollutants. In Paper III (Regional setting), a participatory modelling approach was applied that involved local practitioners from 15 municipalities. The model results showed that strong national policies can drive down CO2 emissions drastically, and that the impacts from sub-national strategies was very limited under these policies. Still, during the discussions with local practitioners it was emphasized that local action is needed for enabling the measures seen as cost-efficient in the model analysis.

    The TIMES-Sweden model was adapted and used to explore key decarbonisation options in passenger and freight transportation, in a whole-energy-systems perspective. The model was disaggregated to capture underlying contextual heterogeneity in passenger transportation found across the country (Paper IV – National setting). The results showed that different policy strategies have different implications depending on the context, thus, underpinning a shift from one-size-fits-all policies into more regionally tailored strategies. Next (Paper V – National setting), the same model was used to investigate principally different modes of decarbonising domestic freight transportation. The results showed that road freight electrification reduces total demand for electricity over the entire energy system compared to the biofuel and the e-fuel pathways respectively, while also freeing biomass for other purposes than producing biofuels for road vehicles.

    Finally, the usefulness of ESOMs to identify policies to accelerate the decarbonization of transportation has been demonstrated, while outlining some challenges. For local level, the necessary data to calibrate the model was often not available, or available but with a system boundary representation incompliant with the model approach (e.g., fuel statistics). At the national level, a new approach was introduced that capture the underlying contextual factors of different actors. While capturing differences between urban, suburban and rural conditions, more research is needed to identify policies that ensure a just transition across socioeconomic groups.

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  • 308.
    Forsberg, Jonas
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Krook-Riekkola, Anna
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Klimatåtgärder inom transportsektorn sett i ett energisystemperspektiv – Utsläppsutrymme och åtgärdskostnader2024Report (Other academic)
  • 309.
    Forsberg, Jonas
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Krook-Riekkola, Anna
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Recoupling Climate Change and Air Quality: Exploring Low-Emission Options in Urban Transportation Using the TIMES-City Model2021In: Energies, E-ISSN 1996-1073, Vol. 14, no 11, article id 3220Article in journal (Refereed)
    Abstract [en]

    Fossil fuels in transportation are a significant source of local emissions in and around cities; thus, decarbonising transportation can reduce both greenhouse gases (GHGs) and air pollutants (APs). However, the degree of these reductions depends on what replaces fossil fuels. Today, GHG and AP mitigation strategies are typically ‘decoupled’ as they have different motivations and responsibilities. This study investigates the ancillary benefits on (a) APs if the transport sector is decarbonised, and (b) GHGs if APs are drastically cut and (c) the possible co-benefits from targeting APs and GHGs in parallel, using an energy-system optimisation model with a detailed and consistent representation of technology and fuel choices. While biofuels are the most cost-efficient option for meeting ambitious climate-change-mitigation targets, they have a very limited effect on reducing APs. Single-handed deep cuts in APs require a shift to zero-emission battery electric and hydrogen fuel cell vehicles (BEVs, HFCVs), which can result in significant upstream GHG emissions from electricity and hydrogen production. BEVs powered by ‘green’ electricity are identified as the most cost-efficient option for substantially cutting both GHGs and APs. A firm understanding of these empirical relationships is needed to support comprehensive mitigation strategies that tackle the range of sustainability challenges facing cities.

  • 310.
    Forsberg, Jonatan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    PFAS in a Swedish wastewater treatment plant: An analysis of the effectiveness of major treatment steps on 33 PFAS2022Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Wastewater treatment plants (WWTP) are known spreaders of per- and polyfluoroalkyl substances (PFAS) into the environment. Luleå University of Technology is conducting a yearlong study in which PFAS concentrations in the different treatment steps are measured at Uddebo treatment plant. This report covers the first four months of the year-long study. The aims of this study are to see what happens with the PFAS concentrations in the treatment processes, if they are above regulated limits, and to see if concentrations at Uddebo are comparable toreference concentrations in Sweden. Sampled PFAS concentrations were taken once per fortnight in incoming wastewater, after primary sedimentation, after Moving Bed Biofilm Reactor (MBBR), after secondary sedimentation and after the pilot treatment plant containing granulated active carbon (GAC) filter when it was in use. Precursors in incoming wastewater and PFAS in sludge were measured in samples taken once per month.

    Comparing the 33 analysed PFAS in wastewater at each sampling point, 30 analysed precursors for PFAS in incoming wastewater and 30 analysed PFAS in sludge, only PFOS and PFOA wereregularly found in both wastewater and in outgoing sludge. This indicates a separation of PFAS in the different medium, with sludge having PFAS where the perfluorinated carbon chain length is grater than 6. Out of the analysed 33 PFAS in wastewater PFOA had the highest median concentration of about 7 ng/l with no significant variation between the wastewater sample points. Similarly, the median concentration of total detected 33 PFAS was around 35 ng/l with no significant variation between the wastewater sample points, indicating no significant treatment of measured PFAS during WWTP. This was also comparable to other WWTP in Sweden. PFBA, PFHxA and PFPeA precursors had the highest concentration of the measured 30 PFAS precursors, however, except for one sampling occasion, no significant deviation in precursor PFAS could be detected during the sampling period. Out of the 30 analysed PFAS in outgoing sludge, PFOS had the highest concentration of 6.8 μg/kg dry weight (dw), but no discernible pattern could be identified between sampling dates due to too few samples. PFOS was foundabove the recommended concentration for sensitive land use (3.0 μg/kg dw), but still within recommendations for less sensitive land use (20.0 μg/kg dw) in Sweden. The median concentration of 13.6 μg/kg dw measured PFAS in sludge makes it well below median Swedish concentration. However, all comparisons to other Swedish WWTPs and background concentrations in Sweden were based on a few studies with few samples, potentially increasing or decreasing the median concentration as more research is conducted.

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  • 311.
    Fotouhi, Abbas
    et al.
    Advanced Vehicle Engineering Centre, School of Aerospace, Transport and Manufacturing (SATM), Cranfield University, Bedfordshire, UK.
    Shateri, Neda
    School of Mechanical, Aerospace and Automotive Engineering, Coventry University, Coventry, UK.
    Laila, Dina Shona
    School of Mechanical, Aerospace and Automotive Engineering, Coventry University, Coventry, UK.
    Auger, Daniel J.
    Advanced Vehicle Engineering Centre, School of Aerospace, Transport and Manufacturing (SATM), Cranfield University, Bedfordshire, UK.
    Electric vehicle energy consumption estimation for a fleet management system2021In: International Journal of Sustainable Transportation, ISSN 1556-8318, E-ISSN 1556-8334, Vol. 15, no 1, p. 40-54Article in journal (Refereed)
  • 312.
    Frostenson, Magnus
    et al.
    Företagsekonomiska institutionen, Uppsala universitet.
    Helin, Sven
    Handelshögskolan, Örebro universitet.
    Sandström, Johan
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Hållbarhetsredovisning: Grunder, praktik och funktion.2012Book (Other (popular science, discussion, etc.))
    Abstract [sv]

    Den här boken ger en introduktion till hållbarhetsredovisning. Boken hjälper dig att förstå bakgrunden till hållbarhetsredovisning, hur man upprättar en hållbarhetsredovisning och vilken funktion den fyller.

  • 313.
    Frostenson, Magnus
    et al.
    Department of Business Studies, Uppsala University.
    Helin, Sven
    School of Business, Örebro University.
    Sandström, Johan
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    The internal significance of codes of conduct in retail companies2012In: Business Ethics. A European Review, ISSN 0962-8770, E-ISSN 1467-8608, Vol. 21, no 3, p. 263-275Article in journal (Refereed)
    Abstract [en]

    This paper focuses on the significance of codes of conduct (CoCs) in the internal work context of two retail companies. A stepwise approach is used. First, the paper identifies in what way employees use and refer to CoCs internally. Second, the function and relevance of CoCs inside the two companies are identified. Third, the paper explains why CoCs tend to function in the identified ways. In both cases, the CoCs are clearly decoupled in the sense that they do not concern the immediate work context of the employees. Counter-intuitively, this facilitates the process of establishing the CoCs. Even though the CoCs are not directly relevant for the employees, they are accepted and embraced with regard to contents, focus and function. Above all, the CoCs seem to confirm and even strengthen employee identity. On the basis of these observations, it is suggested that CoCs should not only be valued in light of their direct organisational consequences or lack of such consequences. The issue is not just whether CoCs are decoupled or not. Rather, it is argued that researchers should consider more closely a two-level analysis that takes into account not only the concrete application of CoCs but also their function and meaning. An implication of this is that what might appear as a decoupled code cannot be dismissed as irrelevant to the ‘core’ business processes of the organisation.

  • 314.
    Fukushima, Kyosuke
    et al.
    Graduate School of Engineering Science, Department of Mathematical Science and Electrical-Electronic-Computer Engineering, Tegata Campus, Akita University, 1-1 Tegata Gakuen Machi, Akita 010-8502, Japan.
    Kabir, Mahmudul
    Graduate School of Engineering Science, Department of Mathematical Science and Electrical-Electronic-Computer Engineering, Tegata Campus, Akita University, 1-1 Tegata Gakuen Machi, Akita 010-8502, Japan.
    Kanda, Kensuke
    Graduate School of Engineering Science, Department of Mathematical Science and Electrical-Electronic-Computer Engineering, Tegata Campus, Akita University, 1-1 Tegata Gakuen Machi, Akita 010-8502, Japan.
    Obara, Naoko
    Graduate School of Engineering Science, Department of Mathematical Science and Electrical-Electronic-Computer Engineering, Tegata Campus, Akita University, 1-1 Tegata Gakuen Machi, Akita 010-8502, Japan.
    Fukuyama, Mayuko
    Graduate School of Engineering Science, Cooperative Major in Life Cycle Design Engineering, Tegata Campus, Akita University, 1-1 Tegata Gakuen Machi, Akita 010-8502, Japan.
    Otsuki, Akira
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering. Ecole Nationale Supérieure de Géologie, GeoRessources, UMR 7359 CNRS, University of Lorraine, 2 Rue du Doyen, Marcel Roubault, BP 10162, 54505 Vandoeuvre-lès-Nancy, France.
    Simulation of Electrical and Thermal Properties of Granite under the Application of Electrical Pulses Using Equivalent Circuit Models2022In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 15, no 3, article id 1039Article in journal (Refereed)
    Abstract [en]

    Since energy efficiency in comminution of ores is as small as 1% using a mechanical crushing process, it is highly demanded to improve its efficiency. Using electrical impulses to selectively liberate valuable minerals from ores can be a solution of this problem. In this work, we developed a simulation method using equivalent circuits of granite to better understand the crushing process with high-voltage (HV) electrical pulses. From our simulation works, we calculated the electric field distributions in granite when an electrical pulse was applied. We also calculated other associated electrical phenomena such as produced heat and temperature changes from the simulation results. A decrease in the electric field was observed in the plagioclase with high electrical conductivity and void space. This suggests that the void volume in each mineral is important in calculating the electrical properties. Our equivalent circuit models considering both the electrical conductivity and dielectric constant of a granite can more accurately represent the electrical properties of granite under HV electric pulse application. These results will help us better understand the liberation of minerals from granite by electric pulse application.

  • 315.
    Furusjö, Erik
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science. IVL Swedish Environmental Research Institute, Climate & Sustainable Cities.
    Ma, Chunyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Carvalho, Lara
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Lundgren, Joakim
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Wetterlund, Elisabeth
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Alkali enhanced biomass gasification with in situ S capture and novel syngas cleaning: Part 1: Gasifier performance2018In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 157, p. 96-105Article in journal (Refereed)
    Abstract [en]

    Previous research shows that alkali addition in entrained flow biomass gasification can increase char conversion and decrease tar and soot formation through catalysis. This paper investigates two other potential benefits of alkali addition: increased slag flowability and in situ sulfur capture.

    Thermodynamic equilibrium calculations show that addition of 2–8% alkali catalyst to biomass completely changes the chemical domain of the gasifier slag phase to an alkali carbonate melt with low viscosity. This can increase feedstock flexibility and improve the operability of an entrained flow biomass gasification process. The alkali carbonate melt also leads to up to 90% sulfur capture through the formation of alkali sulfides. The resulting reduced syngas sulfur content can potentially simplify gas cleaning required for catalytic biofuel production.

    Alkali catalyst recovery and recycling is a precondition for the economic feasibility of the proposed process and is effected through a wet quench. It is shown that the addition of Zn for sulfur precipitation in the alkali recovery loop enables the separation of S, Ca and Mg from the recycle. For high Si and Cl biomass feedstocks, an alternative separation technology for these elements may be required to avoid build-up.

  • 316. Gabrielson, Göran
    et al.
    Grennberg, Kerstin
    Luleå University of Technology.
    Källsortering och lokal kompostering på Landbovägen, S:a Sunderbyn1990Report (Other academic)
  • 317.
    Galkin, Nikolai
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Yang, Chen-Wei
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Berezovskaya, Yulia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Vesterlund, Mattias
    ICE Data Center, RISE Research Institutes of Sweden AB, 97347 Luleå, Sweden.
    Vyatkin, Valeriy
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Department of Electrical Engineering and Automation, Aalto University, 02150 Espoo, Finland.
    On Modelling of Edge Datacentre Microgrid for Participation in Smart Energy Infrastructures2022In: IEEE Open Journal of the Industrial Electronics Society, E-ISSN 2644-1284, Vol. 3, p. 50-64Article in journal (Refereed)
    Abstract [en]

    Datacentres are becoming a sizable part of the energy system and are one of the biggest consumers of the energy grid. The so-called “Green Datacentre” is capable of not only consuming but also producing power, thus becoming an important kind of prosumers in the electric grid. Green datacentres consist of a microgrid with a backup uninterrupted power supply and renewable generation, e.g., using photovoltaic panels. As such, datacentres could realistically be important participants in demand/response applications. However, this requires reconsidering their currently rigid control and automation systems and the use of simulation models for online estimation of the control actions impact. This paper presents such a microgrid simulation model modelled after a real edge datacentre. A case study consumption scenario is presented for the purpose of validating the developed microgrid model against data traces collected from the green edge datacentre. Both simulation and real-time validation tests are performed to validate the accuracy of the datacentre model. Then the model is connected to the automation environment to be used for the online impact estimation and virtual commissioning purposes.

  • 318.
    Gan, Princess Rochelle
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Flotation of Yxsjöberg historical tungsten ore tailings2019Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Tailings dams, due to their sheer size and metal content, pose safety and environmental hazards. The Småltjarnen repository, which hosts material from the largest known tungsten mineralization in Sweden named the Yxsjöberg deposit, is estimated to contain 2.2 million tons of material from previous operations when recovery rates of scheelite, chalcopyrite, and fluorite were low. The repository is also observed to contain at least four of the listed critical raw materials by the European Commission in 2017, namely tungsten, fluorite, beryllium, and bismuth. The amenability of this tailings repository as secondary sources for valuable minerals and metals supports the Raw Material Initiative and the drive of the European Union towards a more circular economy. This masters thesis is part of the REMinE (Improve Resource Efficiency and Minimize Environmental Footprint) project that aims to evaluate the amenability of historical mining waste for re-processing from the technical, economical, and environmental perspectives. The study focuses on work package 3 of the project: Identification of new processing methods for mine waste. Previous work on this repository includes geochemical characterization and physical separation through magnetic and gravity separation tests. Since scheelite, the main mineral of the deposit, is commonly recovered through combinations of gravity separation and flotation methods, it is imperative to investigate the response of the material to flotation tests. Further characterization work and flotation tests were rendered on samples from sampling location 6 (60°02'33.6"N 14°46'30.8"E). Previous work was done on samples from and near sampling location 1, which is southwest from location 6. Characterization methods performed on the material included elemental analysis through ICP-SFMS, X-ray diffraction measurements, and mineral liberation analysis as well as physical characterization through particle size distribution analysis and determination of specific gravity. Based on MLA, the material from the main samples showed good liberation by free surface which is important for flotation processes. Mineral association also showed low percentages between scheelite and other Ca-bearing minerals which is a main concern for scheelite flotation. Comparison of characterization work between the two sampling locations allows information on the repository at a larger scope. The common scheelite flotation collector sodium oleate, as well as novel formulations Atrac 2600 and Berol 8313 from Nouryon were tested in combination with the depressant sodium silicate. Based on mass recovery, grade and recovery, selectivity, required dosage, and the degree to which it is environmentally safe, Atrac 2600 at 400 g/t is deemed to produce the most positive results. Based on characterization of the material and flotation tests, an estimated 222,200 tons of -75 µm can go directly into the flotation circuit with an average grade of 0.2768% WO3 and 0.195% Cu. Approximately 15,000 tons at 0.50% WO3 and 14,000 tons at 0.224% Cu can be recovered at a single flotation. Rough mass balance of the process flowsheet indicates a Cu concentrate at 30% Cu will produce 880.50 tons, while a saleable scheelite concentrate at 65% WO3 will yield 672.16 tons from only the original -75 µm fraction of the material. Including the gravity separation tails intended to join the flotation circuit after grinding, an estimated 1,205.54 tons of scheelite at 65% WO3 and 1.860.20 tons of 30% Cu concentrate can be produced. Aside from this, the gravity separation circuit will still be able to yield 188,000 tons of 0.92% WO3 concentrate, which can be further studied if it can be beneficiated to a saleable product. Value estimation of the products for the recommended flowsheet indicate a total of US$ 17 million for the WO3 and Cu concentrates to be produced from the readily amenable -75 µm fraction to be treated directly by flotation. Inclusion of the gravity separation tails mass into the flotation feed yields a value estimated at US$32 million.

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  • 319.
    Gao, Kai
    et al.
    Institute of Future Cities, The Chinese University of Hong Kong, Hong Kong, China.
    Fong, K. F.
    Division of Building Science and Technology, College of Engineering, City University of Hong Kong, Hong Kong, China.
    Lee, C. K.
    Division of Building Science and Technology, College of Engineering, City University of Hong Kong, Hong Kong, China.
    Lau, Kevin Ka-Lun
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Ng, Edward
    Institute of Future Cities, The Chinese University of Hong Kong, Hong Kong, China.
    Balancing thermal comfort and energy efficiency in high-rise public housing in Hong Kong: Insights and recommendations2024In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 437, article id 140741Article in journal (Refereed)
  • 320.
    Garmabaki, Amir Soleimani
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Thaduri, Adithya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Famurewa, Stephen Mayowa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Adapting Railway Maintenance to Climate Change2021In: Sustainability, E-ISSN 2071-1050, Vol. 13, no 24, article id 13856Article in journal (Refereed)
    Abstract [en]

    Railway infrastructure is vulnerable to extreme weather events such as elevated temperature, flooding, storms, intense winds, sea level rise, poor visibility, etc. These events have extreme consequences for the dependability of railway infrastructure and the acceptable level of services by infrastructure managers and other stakeholders. It is quite complex and difficult to quantify the consequences of climate change on railway infrastructure because of the inherent nature of the railway itself. Hence, the main aim of this work is to qualitatively identify and assess the impact of climate change on railway infrastructure with associated risks and consequences. A qualitative research methodology is employed in the study using a questionnaire as a tool for information gathering from experts from several municipalities in Sweden, Swedish transport infrastructure managers, maintenance organizations, and train operators. The outcome of this questionnaire revealed that there was a lower level of awareness about the impact of climate change on the various facets of railway infrastructure. Furthermore, the work identifies the challenges and barriers for climate adaptation of railway infrastructure and suggests recommended actions to improve the resilience towards climate change. It also provides recommendations, including adaptation options to ensure an effective and efficient railway transport service.

  • 321.
    Gawusu, Sidique
    et al.
    Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21211, USA.
    Jamatutu, Seidu Abdulai
    School of Economics and Management, Nanjing University of Science and Technology, Nanjing, China.
    Zhang, Xiaobing
    School of Energy and Power and Engineering, Nanjing University of Science and Technology, Nanjing, China.
    Moomin, Solahudeen Tando
    Global Development Institute, School of Environment, Education and Development, University of Manchester, Manchester, UK.
    Ahmed, Abubakari
    Department of Urban Design and Infrastructure Studies, Faculty of Planning and Land Management, SD Dombo University of Business and Integrated Development Studies, Bamahu-Wa, Ghana.
    Mensah, Rhoda Afriyie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Das, Oisik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Ackah, Ishmael
    Department of Economics, School of Liberal Arts and Social Science, Ghana Institute of Management and Public Administration, Accra, Ghana.
    Spatial analysis and predictive modeling of energy poverty: insights for policy implementation2024In: Environment, Development and Sustainability, ISSN 1387-585X, E-ISSN 1573-2975Article in journal (Refereed)
    Abstract [en]

    Understanding and alleviating energy poverty is critical for sustainable development. This study harnesses a suite of Machine Learning (ML) algorithms to predict Multidimensional Energy Poverty Index (MEPI) and to highlight the spatial distribution of energy poverty. We assess the predictive accuracy of Random Forest (RF), Support Vector Machine (SVM), Artificial Neural Network (ANN), Multiple Linear Regression (MLR), and XGBoost models. The RF model outperforms others, achieving an R2 value of 0.92 and a Pearson Correlation Coefficient (PCC) of 0.97 on the testing dataset, indicative of a highly accurate prediction capability. XGBoost also demonstrates strong predictive power with corresponding values of 0.88 and 0.94, respectively. Our spatial analysis, revealing significant clustering of energy poverty with a Global Moran’s I value of 150.39, indicates that energy poverty is not only geographically concentrated but also intricately linked to socio-economic factors such as income levels, access to education, and nutritional status. These insights underscore the necessity of region-specific and socio-economically informed policy interventions. The results inform targeted interventions, particularly highlighting the critical roles of education and nutrition in mitigating energy poverty. The RF model’s accuracy rate of 92% on the testing set suggests that improvements in these sectors could significantly influence MEPI scores. The integration of ML and spatial analysis offers a nuanced and actionable understanding of energy poverty, paving the way for targeted, evidence-based policy formulation aimed at achieving SDG7: ensuring access to affordable, reliable, sustainable, and modern energy for all.

  • 322.
    Gawusu, Sidique
    et al.
    Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21211, United States.
    Tando, Moomin Solahudeen
    Global Development Institute, School of Environment, Education and Development, The University of Manchester, United Kingdom.
    Ahmed, Abubakari
    Department of Urban Design and Infrastructure Studies, Faculty of Planning and Land Management, SD Dombo, University of Business and Integrated Development Studies, Bamahu-Wa, Ghana.
    Jamatutu, Seidu Abdulai
    School of Economics and Management, Nanjing University of Science and Technology, Nanjing, China.
    Mensah, Rhoda Afriyie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Das, Oisik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Structural and Fire Engineering.
    Mohammed, Abdul-Latif
    Department of Management, Newcastle Business School, The University of Newcastle, Australia.
    Yakubu, Ibrahim Nandom
    Department of Business and Education, School of Business, University for Development Studies, Tamale, Ghana.
    Ackah, Ishmael
    Department of Economics, School of Liberal Arts and Social Science, Ghana Institute of Management and Public Administration, Accra, Ghana.
    Decentralized energy systems and blockchain technology: Implications for alleviating energy poverty2024In: Sustainable Energy Technologies and Assessments, ISSN 2213-1388, E-ISSN 2213-1396, Vol. 65, article id 103795Article, review/survey (Refereed)
  • 323.
    Ghanei, Javad
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Evaluation of the relation between ore texture and grindability2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • 324.
    Ghayour, Laleh
    et al.
    Department of Natural Resources Engineering and Environment, Azad Hamedan University, Hamedan 65181-15743, Iran.
    Neshat, Aminreza
    Department of GIS/RS, Faculty of Natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran.
    Paryani, Sina
    Department of GIS/RS, Faculty of Natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran.
    Shahabi, Himan
    Department of Geomorphology, Faculty of Natural Resources, University of Kurdistan, Sanandaj 66177-15175, Iran; Department of Zrebar Lake Environmental Research, Kurdistan Studies Institute, University of Kurdistan, Sanandaj 66177-15175, Iran.
    Shirzadi, Ataollah
    Department of Rangeland and Watershed Management, Faculty of Natural Resources, University of Kurdistan, Sanandaj 66177-15175, Iran.
    Chen, Wei
    College of Geology & Environment, Xi’an University of Science and Technology, Xi’an 710054, China.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Geertsema, Marten
    Research Geomorphologist, Ministry of Forests, Lands, Natural Resource Operations and Rural Development, 499 George Street, Prince George, BC V2L 1R5, Canada.
    Pourmehdi Amiri, Mehdi
    Department of Geographic Information System and Remote Sensing, Aban Haraz Hitcher Education Institute, Amol 46131-46391, Iran.
    Gholamnia, Mehdi
    Department of Civil Engineering, Islamic Azad University, Sanandaj Branch, Sanandaj 6616935391, Iran.
    Dou, Jie
    Three Gorges Research Center for Geo-Hazards, Ministry of Education, China University of Geosciences, Wuhan 430074, China.
    Ahmad, Anuar
    Department of Geoinformation, Faculty of Built Environment and Surveying, Universiti Teknologi Malaysia (UTM), Johor Bahru 81310, Malaysia.
    Performance Evaluation of Sentinel-2 and Landsat 8 OLI Data for Land Cover/Use Classification Using a Comparison between Machine Learning Algorithms2021In: Remote Sensing, E-ISSN 2072-4292, Vol. 13, no 7, article id 1349Article in journal (Refereed)
    Abstract [en]

    With the development of remote sensing algorithms and increased access to satellite data, generating up-to-date, accurate land use/land cover (LULC) maps has become increasingly feasible for evaluating and managing changes in land cover as created by changes to ecosystem and land use. The main objective of our study is to evaluate the performance of Support Vector Machine (SVM), Artificial Neural Network (ANN), Maximum Likelihood Classification (MLC), Minimum Distance (MD), and Mahalanobis (MH) algorithms and compare them in order to generate a LULC map using data from Sentinel 2 and Landsat 8 satellites. Further, we also investigate the effect of a penalty parameter on SVM results. Our study uses different kernel functions and hidden layers for SVM and ANN algorithms, respectively. We generated the training and validation datasets from Google Earth images and GPS data prior to pre-processing satellite data. In the next phase, we classified the images using training data and algorithms. Ultimately, to evaluate outcomes, we used the validation data to generate a confusion matrix of the classified images. Our results showed that with optimal tuning parameters, the SVM classifier yielded the highest overall accuracy (OA) of 94%, performing better for both satellite data compared to other methods. In addition, for our scenes, Sentinel 2 date was slightly more accurate compared to Landsat 8. The parametric algorithms MD and MLC provided the lowest accuracy of 80.85% and 74.68% for the data from Sentinel 2 and Landsat 8. In contrast, our evaluation using the SVM tuning parameters showed that the linear kernel with the penalty parameter 150 for Sentinel 2 and the penalty parameter 200 for Landsat 8 yielded the highest accuracies. Further, ANN classification showed that increasing the hidden layers drastically reduces classification accuracy for both datasets, reducing zero for three hidden layers.

  • 325.
    Ghodrati, Behzad
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, UdayLuleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.Schunnesson, HåkanLuleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Proceeding of the 26th International Symposium on Mine Planning and Equipment Selection: MPES 20172017Conference proceedings (editor) (Refereed)
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  • 326.
    Ghosh, Rajib
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Assessment of rock mass quality and its effects on charge ability using drill monitoring technique2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    For an efficient mining operation, it is essential to have as much information as possible aboutthe ore to be excavated and the rock masses surrounding the ore. Geological information andthe content and distribution of extractable minerals, are central concerns for long term mineplanning. However, for mine stability and production scheduling, the mechanical conditionsof ore and side rock are also very important. The underground mining process normallyconsists of a number of unit operations, such as drilling, charging, blasting, loading,transportation, hoisting etc., linked in a production chain. The quality of the initial operations(drilling, charging and blasting) normally defines the pre-conditions for the following loadingand transportation processes in the mine. The ability to fully charge holes as planned has beenidentified as one of the major obstacles for smooth fragmentation. Course or unevenfragmentation will, for example, significantly affect the loading and transportation efficiencyin the downstream production chain.Earlier studies in LKAB’s Malmberget mine have shown that the chargeability is on averagearound 90%. However, individual levels can have an average chargeability of only 70% andindividual rings, at those levels, can suffer from chargeability as low as 50%. A significantpart of these problems has its origin in geo-mechanical problems in the rock mass. Therefore,detailed knowledge of the rock mass condition surrounding the boreholes is essential toimprove the planning and execution of the charging works in a mine and to improve overallfragmentation and production efficiency.The focus of this thesis is therefore to define and evaluate geo-mechanical features in thedrilled rock mass effecting chargeability, and to evaluate drill monitoring technique for theassessment of rock mass quality and its effects on borehole’s chargeability using hydraulic In-The-Hole (ITH) percussive drilling.The research is based on literature review, drill-monitoring data, borehole filming, on-lineproduction database and monitoring of charging operation. Statistical methods are used toanalyse drill data. The data have been collected from LKAB’s underground mine inMalmberget, Sweden.Several rock mass conditions including caving, shearing, deformation, fracturing, cavities,solid rock, etc., have been identified during filming of 361 production boreholes.Measurement While Drilling (MWD) technique has been used to assess the quality of thepenetrated rock mass. In order to do so, a detailed analysis of the drilling system and thedrilling control including how monitored parameters relate to each other and to the penetratedrock mass conditions, has been performed. The results show that the MWD data containpronounced hole length dependent trends, both linear and step-wise linear, for mostparameters. By combining the borehole filming and the analyses of monitored drillparameters, the drilling responds to each geo-mechanical features in the rock mass is furtherdemonstrated. High correlation has been found between the geo-mechanical rock properties(fractures, cavities, solid rocks, etc.,), and the registered drilling system’s response. Theanalyses show that the responses from the drill monitoring system can distinguish between solid rock, fracture zone, cavity and cave-in. Based on the correlation between the registereddrilling system’s responses and the geo-mechanical features, a geo-mechanical model isdeveloped to assess the borehole chargeability. Principal Component Analysis (PCA) isperformed to model this relationship. The developed model can distinguish fans, or parts offans, with solid, non-fractured rocks where no chargeability problems can be expected, fromfans, or part of fans, with fractures, cavities or cave-in risks, where chargeability problemscan be expected. The model shows high potential for identifying charging problems in theborehole, and has been verified and validated by following an actual charging operation in thereal production environment.

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  • 327.
    Ghosh, Rajib
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Gustafson, Anna
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Monitoring of Drill System Behavior for Water-Powered in-the-hole (ITH) drilling2017In: Minerals, E-ISSN 2075-163X, Vol. 7, no 7, article id 121Article in journal (Refereed)
    Abstract [en]

    A detailed understanding of the drilling system and the drilling control is required to correctly interpret rock mass conditions based on monitored drilling data. This paper analyses data from hydraulic in-the-hole (ITH) drills used in LKAB’s Malmberget mine in Sweden. Drill parameters, including penetration rate, percussive pressure, feed pressure, and rotation pressure, are monitored in underground production holes. Calculated parameters, penetration rate variability, rotation pressure variability, and fracturing are included in the analysis to improve the opportunity to predict rock mass conditions. Principal component analysis (PCA) is used to address non-linearity and variable interactions. The results show that the data contain pronounced hole length-dependent trends, both linear and step-wise linear, for most parameters. It is also suggested that monitoring can be an efficient way to optimize target values for drill parameters, as demonstrated for feed force. Finally, principal component analysis can be used to transfer a number of drill parameters into single components with a more straightforward geomechanical meaning

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  • 328.
    Goffetti, Giulia
    et al.
    Ecodynamics Group, Department of Earth, Environmental and Physical Sciences, University of Siena, Siena, Italy.
    Böckin, Daniel
    Division of Environmental Systems Analysis, Chalmers University of Technology, Gothenburg, Sweden.
    Baumann, Henrikke
    Division of Environmental Systems Analysis, Chalmers University of Technology, Gothenburg, Sweden.
    Tillman, Anne-Marie
    Division of Environmental Systems Analysis, Chalmers University of Technology, Gothenburg, Sweden.
    Zobel, Thomas
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Business Administration and Industrial Engineering.
    Towards sustainable business models with a novel life cycle assessment method2022In: Business Strategy and the Environment, ISSN 0964-4733, E-ISSN 1099-0836, Vol. 31, no 5, p. 2019-2035Article in journal (Refereed)
    Abstract [en]

    Business model (BM) innovation for sustainability is hampered by a lack of tools for environmental assessment and guidance at the BM level. Conventional life cycle assessment (LCA) neglects the economic and socio-technical mechanisms within a BM, and tools based on the BM canvas (BMC) cannot provide recommendations substantiated by environmental data. Here, a new method, BM-LCA, is applied to a case comparing the selling and renting of jackets, using profit as basis of comparison. Results identify how business parameters influence environmental performance, permitting analysis for decoupling within a business practice. This is made possible by the unique way the method links physical life cycle and the monetary flows of a BM. Usefulness of BM-LCA is discussed relative to BM innovation, business strategy and similar tools. BM-LCA provides insights into a broad range of BM elements and emerges as useful for business strategy. By measuring BM environmental performance, it helps determine what BM to compete with and support critical analysis of business against greenwashing. BM-LCA also enables identification of BM elements in greatest need of environmental innovation. BM-LCA appears as a promising tool for guiding business companies towards sustainability, filling a space between LCA and BMC. The method offers a practical way for business and LCA experts to merge their respective knowledge.

  • 329.
    Golshani, T.
    et al.
    Department of Mining Engineering, Science and Research Branch,Islamic Azad University.
    Jorjani, E.
    Department of Mining Engineering, Science and Research Branch,Islamic Azad University.
    Chelgani, Saeed Chehreh
    Young Researchers and Elites club, Science and Research Branch, Islamic Azad University, Iran.
    Shafaei, S. Z.
    School of Mining Engineering, University of Tehran, Iran.
    Nafechi, Y. H.
    epartment of Mining Engineering, Science and Research Branch, Islamic Azad University.
    Modeling and process optimization for microbial desulfurization of coal by using a two-level full factorial design2013In: International Journal of Mining Science and Technology, ISSN 2095-2686, Vol. 23, no 2, p. 261-265Article in journal (Refereed)
    Abstract [en]

    The microbial sulfur removal was investigated on high sulfur content (1.9%) coal concentrate from Tabas coal preparation plant. A mixed culture of ferrooxidans microorganisms was isolated from the tailing dam of the plant. Full factorial method was used to design laboratory test and to evaluate the effects of pH, particle size, iron sulfate concentration, pulp density, and bioleaching time on sulfur reduction. Statistical analyses of experimental data were considered and showed increases of pH and particle size had negative effects on sulfur reduction, whereas increases of pulp density and bioleaching time raised microbial desulfurization rate. According to results of designing, and regarding statistical factors, the optimum values for maximum sulfur reduction were obtained; pH (1.5), particle size (−180 μm), iron sulfate concentration (2.7 mmol/L), pulp density (10%) and bioleaching time (14 d), which leaded to 51.5% reduction from the total sulfur of sample.

  • 330.
    Gonzalez, Felipe
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    The source of the sulphur fluctuations in the Malmberget magnetite concentrate2023Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    LKAB is one of the leading European companies in exploitation of iron while mining more than 80% of all iron ore in the European Union. The iron products are expected to be high quality regarding their content of impurities. When sulphur content exceeds a certain level in concentrates, expensive desulphurization process is required to avert technical problems in steel and alloys and environmental issues as emissions during the processing of iron ore. In order to prevent or rectify the sulphur impact, it is critical to understand the sources of sulphur in the ore and why they end up in the concentrate. This study focuses on sulphur tracking from concentrates by chemical and mineralogical characterisation of feed and concentrates of LKAB beneficiation plant in Malmberget. Previous studies on sulphur balance during processing have shown that the greatest impact is the sulphur content of the constituent material of the feed. This study aims to shed light on the sulphur fluctuations detected in the Malmberget magnetite concentrate by identifying its source in terms of mineralogy.

    For this study, concentrate samples were collected covering episodes with high-sulphur peaks as well as regular low background levels. The scope of the study also includes mineralogical investigation of the drill core samples. Analytical methods such as micro-X-rays fluorescence (µ-XRF), Scanning electron microscopy (SEM) – Energy dispersive spectroscopy (EDS), Quantitative Evaluation of Materials by Scanning Electron Microscopy (QEMSCAN) – Particle mineral analysis (PMA), Electron probe micro analyzer (EPMA), and X-rays fluorescence (XRF) were used for characterization of the ore and concentrate products.

    Selected drill core intervals contain visible sulfide minerals. Different mineralization styles were observed including patchy, dissemination, discontinuous veinlets, and veins. Pyrrhotite occurs preferentially as fine grains (50-150μm) along the edge of coarse pyrite grains (200μm-2mm). Pyrite is the main sulphur bearing mineral in most of samples. Pyrite grade is highly variable, ranging from 0.3 wt% to 13.2 wt% across the analysed drill cores. Pyrrhotite is the second most abundant sulphur bearing mineral. Pyrrhotite grades range from 0.1 wt% to 2.2 wt%. Chalcopyrite occurrences are variable ranging from 0.0 to 0.5 wt%.

    In the concentrates, chemical and mineralogical analysis allowed to track the type and trend of the sulphide minerals in size fractions. Pyrrhotite (mostly liberated) and pyrite (mostly locked with magnetite) are the major sulphur carriers in the concentrates. There is an increase in observable pyrrhotite particles present in the samples corresponding to high sulphur events. Pyrrhotite shows generally higher deportment among sulphides in finer fractions and these finer fractions have the highest sulphur grade. Specimens found were pyrite, pyrrhotite and chalcopyrite, as well as some minor sphalerite and cobaltite. Pyrite in polymetallic assemblages as well as fully liberated pyrrhotite are the most common state of the sulphide particles. Sulphur comes from sulphide minerals primarily, while sulphates are successfully removed in the process (with exception of few baryte particles that were spotted). Finally, it was concluded that high sulphur peaks are correlated with increased pyrrhotite content of the monoclinic type in the concentrates.

  • 331.
    Gonçalves, Pedro Pereira
    et al.
    Ecole Nationale Supérieure de Géologie, GeoRessources UMR 7359 CNRS, University of Lorraine, Vandoeuvre-lès-Nancy, France.
    Otsuki, Akira
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Determination of Liberation Degree of Mechanically Processed Waste Printed Circuit Boards by Using the Digital Microscope and SEM-EDS Analysis2019In: Electronics, E-ISSN 2079-9292, Vol. 8, no 10, article id 1202Article in journal (Refereed)
    Abstract [en]

    Characterization of heterogeneous materials, such as particles from mechanically processed waste printed circuit boards, is a challenging task. The majority of characterization methods either give average information or information that is very limited and in a tiny area of specific interest. That said, capturing such heterogeneity is significantly important for any kind of processes. Degree of liberation, indicating how much the target component is liberated from the non-valuable components, is a key property to determine the success of subsequent process for valuable material recovery. This work analyzed the degree of liberation of metals within the products of hammer milling process via the combination of image acquisition and analysis. The digital microscope and a scanning electron microscope (SEM) coupled with the energy dispersive spectroscopy (EDS) were used for image acquisition and elemental mapping, in order to evaluate the selective liberation under different milling conditions (i.e., feed mass, milling time) for different metals (mainly Cu and Al) and particle size fractions. The obtained liberation degree was also modelled and determined the liberation parameters that were compared. The results showed that the degree of liberation significantly depend on the milling conditions and metals we analyzed, and well correlated with the selective metal enrichment behavior. Results between the two methods showed some similarities and discrepancies. The advantages and disadvantages of the above two methods were identified and discussed in the paper, in addition to their methodological developments.

  • 332.
    Grafström, Jonas
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Technological Change in Service of the Environment2018Other (Other academic)
    Abstract [en]

    Jonas Grafstrom provides an outline of how technological change in the renewable energy field can contribute to mitigate climate issues. Such knowledge enables policy makers (e.g., at the EU level) to make better and more informed decisions.

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  • 333.
    Granestrand, Jonas
    et al.
    KTH Royal Institute of Technology, Department of Chemical Engineering, Stockholm, Sweden.
    Dahlin, Sandra
    KTH Royal Institute of Technology, Department of Chemical Engineering, Stockholm, Sweden.
    Immele, Oliver
    Technical University of Munich, Department of Chemistry, Garching, Germany.
    Schmalhorst, Leonhard
    Technical University of Munich, Department of Chemistry, Garching, Germany.
    Lantto, Cornelia
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Nilsson, Marita
    Scania CV, Emission Solutions Development, Catalytic Converter and Particulate Filter Performance, Södertälje, Sweden.
    París, Rodrigo Suárez
    Scania CV, Materials Technology - Engine Performance and Emissions, Södertälje, Sweden.
    Regali, Francesco
    Scania CV, Materials Technology - Engine Performance and Emissions, Södertälje, Sweden.
    Pettersson, Lars J.
    KTH Royal Institute of Technology, Department of Chemical Engineering, Stockholm, Sweden.
    Catalytic aftertreatment systems for trucks fueled by biofuels - Aspects on the impact of fuel quality on catalyst deactivation2018In: Catalysis, ISSN 0140-0568, E-ISSN 1465-1920, Vol. 30, p. 64-145Article, review/survey (Refereed)
    Abstract [en]

    The issue of sustainable energy supply is a global problem for pursuing future endeavours in the energy area. In countries such as China and India there is a tremendous growth at the moment, which is envisaged by an ever growing demand for vehicles. Hence, one of the grand challenges of society is to meet the demands for sustainable and environmentally-friendly technologies in the transport sector. One way to tackle the problem of growing concentrations of carbon dioxide, which is believed to contribute to global warming, is the use of biofuels. It is becoming more and more evident that global warming is partly due to increasing anthropogenic carbon dioxide emissions. An important contribution to these emissions is the use of fossil fuels in the transport sector. Hence, more efficient engines and an increased use of biofuels would be a step in the right direction. Although new propulsion systems are emerging, such as hybrid power-trains and fuel cell systems, analysis shows that combustion systems with excess oxygen, such as the diesel engine, will be the most important engine concept for the next 20 years. In this paper we will identify the specific challenges related to the production and use of biofuels in heavy-duty trucks and how they influence the catalytic units in the emission after-treatment system in the truck. Biofuels, such as biodiesel, contain potential poisons for the vehicle exhaust after-treatment, such as potassium, sodium, magnesium, phosphorus, zinc, sulfur and other compounds.

  • 334.
    Gren, Lisa
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    The mass balance of compounds in source-separated blackwater treatment at RecoLab, Helsingborg2024Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As an alternative to conventional wastewater treatment, the use of source-separating wastewater systems is growing in popularity. This study evaluated processes at RecoLab, a source-separating wastewater treatment and recovery plant, which treats blackwater, greywater and food waste streams from the nearby residential area of Oceanhamnen, in Helsingborg, Sweden. The focus of the study was on the blackwater stream which included the biogas production and the struvite precipitation and ammonia stripping processes which recovered nutrients in the form of phosphorus and nitrogen.

    The objectives were to analyse the variation in quantity and quality of incoming blackwater to RecoLab during 2023 and to quantify the mass flows of total solids, chemical oxygen demand, phosphorus, and nitrogen throughout the blackwater treatment process. Furthermore, the end products, including biogas, sludge, and recovered nutrients were analysed in terms of quantity and quality and then compared with products from conventional wastewater treatment plants. Data collected during 2023, including water samples and flow measurements at various points in the blackwater treatment process, were used to calculate mass balances of the investigated parameters.

    From the results, it was seen that the anaerobic digestion in RecoLab produced more biogas than most conventional wastewater treatment plants (150 m3 CH4/week or approximately 88 kWh/PE/year), with the biogas having a large impact on the total solids and chemical oxygen demand mass balances. The digestion yielded a sludge with low heavy metal concentrations (13 mg Cd/kg P), making it safe for agricultural use. Low metal concentrations were also found in the struvite (0.68 mg Cd/kg P), although decreasing metal concentrations over time point to a diffuse source of leaching in the equipment. The nutrient recovery as sludge and struvite, a recovery of 27% of the total phosphorus and 2.5% of the total nitrogen, was impacted by the struvite precipitation process showing a low collection grade. Substantial total phosphorus and total solids losses were found over the struvite precipitation process in the mass balances. Total nitrogen loss over the struvite precipitation process was mainly deemed to be due to aeration, though a possible overestimated value. Hypothetical calculations of the ammonia stripper showed great potential for nitrogen recovery in the form of ammonium sulphate, where a fully working ammonia stripper would contribute with the largest fraction of nutrient recovery in the RecoLab plant.

    Overall, the thesis presents an alternative to conventional wastewater treatment methods by possibilities to enhance nutrient recovery and support circular economy principles. However, the study highlights several areas for improving the blackwater treatment at RecoLab, such as optimizing the hydrocyclone to increase the struvite recovery and conducting direct measurements of the aeration process to better understand nitrogen pathways. The implementation of source-separating systems, as demonstrated by RecoLab, can serve as a model for future urban developments, aiming for resource efficiency and minimal environmental impact.

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  • 335.
    Grennberg, Kerstin
    Luleå University of Technology.
    Resursbevarande byggteknik1996Report (Other academic)
  • 336.
    Grennberg, Kerstin
    et al.
    Luleå University of Technology.
    Nilsson, Ragnar
    Småskalig kompostering: en förstudie1990Report (Other academic)
  • 337.
    Grennberg, Kerstin
    et al.
    Luleå University of Technology.
    Sandström, Peter
    Tillväxt för björkplantor odlade i torv med restprodukter som gödselmedel1990Report (Other academic)
  • 338.
    Grigat, Felix
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. ONERA.
    Optimizing the architecture of the Salammbô-EnKF data assimilation tool for radiation belt modeling2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 339.
    Guiral Vega, Juan Sebastian
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    Textural and Mineralogical Characterization of Li-pegmatite Deposit: Using Microanalytical and Image Analysis to Link Micro and Macro Properties of Spodumene in Drill Cores.: Keliber Lithium Project, Finland.2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Lithium represents one of the strategic elements for the rest of the 21st century due to its increasing demand in technological applications. Therefore, new efforts should be focused on the optimization of mineral characterization processes, which link the ore properties with its behaviour during downstream processes. These efforts should result in reducing operational risks and increasing resources utilization. The methodology presented in this study is based on the application of several classification techniques, aiming the mineral and textural characterization of two spodumene pegmatite deposits within the Keliber Lithium Project.

    Twelve textural classes have been proposed for the textual classification of the ore, which have been defined through the recognition of the main mineral features at macro- and micro-scale. The textural classification was performed through the application of drill core logging and scanning electron microscopy. Six classes are proposed to describe the characteristics of the spodumene ore. Six additional classes describe the main properties of the rocks surrounding the ore zone.

    Image analysis was implemented for the generation of mineral maps and the subsequent quantification of spodumene and Li2O within the analysed drill core images. The image segmentation process was executed in Fiji-ImageJ and is based on eight mineral classes and a set of seven feature extraction procedures. Thus, quantification of spodumene and Li2O is estimated by textural class. Hyperspectral images were used as a reference for assessing the estimations made through images analysis.

    A machine learning model in Weka allowed forecasting the behaviour of the twelve textural classes during spodumene flotation. This model is fed by metallurgical data from previous flotation tests and uses Random Forest classifier.

    The proposed methodology serves as an inexpensive but powerful approach for the complete textural characterization of the ore at Keliber Lithium Project. It provides information about: (1) mineral features at different scales, (2) spatial distribution of textures within the pegmatite body, (3) quantification of spodumene and Li2O within the drill cores and (4) processing response of each textural class. However, its application requires wide knowledge and expertise in the mineralogy of the studied deposits.

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  • 340.
    Gullman, Isak
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Improved prediction of biogas production at Uddebo wastewater treatment plant: Substrate modelling in SIMCA2021Independent thesis Advanced level (professional degree), 300 HE creditsStudent thesis
    Abstract [en]

    Anaerobic digestion is a complex process, dependent on multiple factors, which can be made more stable and efficient with the help of process models. A more stable process could reduce biogas torching, which increases the amount of renewable energy available for heat- and electricity production and vehicle fuel. 

    Fluctuations in the produced biogas at Uddebo WWTP in Luleå, Sweden, has been observed, where imported industrial waste was suspected to be the cause. The purpose of this master thesis was to increase the predictability of the biogas production at Uddebo WWTP by creating a process model based on historical data. The historical data consisted of quantitative data of the substrates loaded into the anaerobic digestor and biogas collected from the digestor. 

    The results showed that the calculated error between modelled and measured biogas production was <20%, which was considered good. However, due to the demarcation of this report, many variables were ignored in the creation of the model. Further research is therefore a requirement for the model to function properly: 

    • The error should be reduced to <10%, 
      • This could be done by increasing the period and resolution to
        • include and statistically secure fast and seasonal variations. 
        • make qualitative modelling easier, i.e., prediction of the biomethane amount in the biogas. 
    • The industrial liquid waste storage should be included in the calculation.  
    • A more detailed analysis of all substrates is needed to make the comparison between the literature based and measured production more realistic. 
    • Expanding the demarcation of the model to also include the environment in the digestor. This could also increase the total amount of biogas produced. 
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  • 341.
    Gunnvard, Per
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Garcia, Nelson
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mattsson, Hans
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Jia, Qi
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Monitoring of a timber pile-supported road embankment2022In: Proceedings Eleventh International Conference on the Bearing Capacity of Roads, Railways and Airfields / [ed] Inge Hoff, Helge Mork, Rabbira Garba Saba, London: CRC Press, 2022, Vol. 2, p. 337-347Conference paper (Refereed)
    Abstract [en]

    Timber piling allows for a solution with lower carbon footprint than concrete or steel piling, yet there exist few well-documented cases of modern timber piled embankments. In this paper, field measurements on a geosynthetic-reinforced timber pile-supported road embankment are reported and evaluated. The monitored road embankment is a section of a newly reconstructed semi-motorway in northern Sweden. The embankment was constructed on 8 m long untreated timber piles with 1.1 m spacing in a triangular pattern, without pile caps. On top of that, a 1.7 m high embankment was constructed, reinforced by two layers of biaxial geogrids. A long-term monitoring program is being carried out from when the semi-motorway was reconstructed. This study presents results from the first year of monitoring. The measurements include the load on the pile heads and subsoil, geogrid strain, pore water pressures, and settlements. The measurements show the development of arching over time, the interlocking of geogrid and embankment material, the subsoil consolidation, etc. The results of the monitoring are compared with results of analytical models from recommendations and codes.

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  • 342.
    Guntoro, Pratama Istiadi
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Minerals and Metallurgical Engineering.
    X-ray microcomputed tomography (µCT) as a potential tool in Geometallurgy2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In recent years, automated mineralogy has become an essential tool in geometallurgy. Automated mineralogical tools allow the acquisition of mineralogical and liberation data of ore particles in a sample. These particle data can then be used further for particle-based mineral processing simulation in the context of geometallurgy. However, most automated mineralogical tools currently in application are based on two-dimensional (2D) microscopy analysis, which are subject to stereological error when analyzing three-dimensional(3D) object such as ore particles. Recent advancements in X-ray microcomputed tomography (µCT) have indicated great potential of such system to be the next automated mineralogical tool. µCT's main advantage lies on its ability in monitoring 3D internal structure of the ore at resolutions down to few microns, eliminating stereological error obtained from 2D analysis. Aided with the continuous developments of computing capability of 3D data, it is only the question of time that µCT system becomes an interesting alternative in automated mineralogy system.

    This study aims to evaluate the potential of implementing µCT as an automated mineralogical tool in the context of geometallurgy. First, a brief introduction about the role of automated mineralogy in geometallurgy is presented. Then, the development of µCT system to become an automated mineralogical tool in the context of geometallurgy andprocess mineralogy is discussed (Paper 1). The discussion also reviews the available data analysis methods in extracting ore properties (size, mineralogy, texture) from the 3D µCT image (Paper 2). Based on the review, it was found that the main challenge inperforming µCT analysis of ore samples is the difficulties associated to the segmentation of the mineral phases in the dataset. This challenge is adressed through the implementation of machine learning techniques using Scanning Electron Microscope (SEM) data as a reference to differentiate the mineral phases in the µCT dataset (Paper 3).

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  • 343.
    Guptha, Guru Chythanya
    et al.
    Department of Water Resources Development and Management, Indian Institute of Technology Roorkee, Roorkee, India.
    Swain, Sabyasachi
    Department of Water Resources Development and Management, Indian Institute of Technology Roorkee, Roorkee, India.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Taloor, Ajay Kumar
    Department of Remote Sensing and GIS, University of Jammu, Jammu, India.
    Dayal, Deen
    Department of Water Resources Development and Management, Indian Institute of Technology Roorkee, Roorkee, India.
    Evaluation of an urban drainage system and its resilience using remote sensing and GIS2021In: Remote Sensing Applications: Society and Environment, ISSN 2352-9385, Vol. 23, article id 100601Article in journal (Refereed)
    Abstract [en]

    The increasing number of pluvial floods due to extreme climatic events or poor maintenance of the drainage networks urge for assessing the performance of the urban drainage system (UDS). This paper presents a comprehensive evaluation of the UDS of Gurugram City, India. While the limited availability of sub-hourly precipitation and finer resolution geospatial data pose major challenges in the detailed analyses through Storm Water Management Model (SWMM), it was circumvented by utilizing the high-resolution remotely sensed datasets viz., IMERG (half-hourly precipitation data from 2000 to 2019), ALOS PALSAR (Digital Elevation Model) and Sentinel-2 (land use/land cover). Functional failure scenarios (i.e., the combinations of climate change and urbanization) were simulated to assess the impacts on the resilience of the UDS. The modelling results showed that individually, climate change would impose a more serious threat than urbanization, whereas their combinations would significantly hamper the resilience of the UDS. The structural failure (only single link-failure) scenarios were analyzed, and 11 out of 25 conduits were identified to be non-resilient. The study highlights the importance of the readily available remote sensing datasets, which fill the gap of non-availability of ground-based datasets at desirable resolutions, especially in developing countries.

  • 344.
    Gusiatin, Zygmunt Mariusz
    et al.
    Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Carabante, Ivan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Radziemska, Maja
    Institute of Environmental Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland; Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, 61300 Brno, Czech Republic.
    Brtnicky, Martin
    Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of AgriSciences, Mendel University in Brno, Zemedelska 1, 61300 Brno, Czech Republic; Institute of Chemistry and Technology of Environmental Protection, Faculty of Chemistry, Brno University of Technology, Purkynova 118, 61200 Brno, Czech Republic.
    Remediation of smelter contaminated soil by sequential washing using biosurfactants2021In: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 18, no 24, article id 12875Article in journal (Refereed)
    Abstract [en]

    This paper presents experimental results from the use of biosurfactants in the remediation of a soil from a smelter in Poland. In the soil, concentrations of Cu (1659.1 mg/kg) and Pb (290.8 mg/kg) exceeded the limit values. Triple batch washing was tested as a soil treatment. Three main variants were used, each starting with a different plant-derived (saponin, S; tannic acid, T) or microbial (rhamnolipids, R) biosurfactant solution in the first washing, followed by 9 different sequences using combinations of the tested biosurfactants (27 in total). The efficiency of the washing was determined based on the concentration of metal removed after each washing (CR), the cumulative removal efficiency (Ecumulative) and metal stability (calculated as the reduced partition index, Ir, based on the metal fractions from BCR sequential extraction). The type of biosurfactant sequence influenced the CR values. The variants that began with S and R had the highest average Ecumulative for Cu and Pb, respectively. The Ecumulative value correlated very strongly (r > 0.8) with the stability of the residual metals in the soil. The average Ecumulative and stability of Cu were the highest, 87.4% and 0.40, respectively, with the S-S-S, S-S-T, S-S-R and S-R-T sequences. Lead removal and stability were the highest, 64–73% and 0.36–0.41, respectively, with the R-R-R, R-R-S, R-S-R and R-S-S sequences. Although the loss of biosurfactants was below 10% after each washing, sequential washing with biosurfactants enriched the soil with external organic carbon by an average of 27-fold (S-first variant), 24-fold (R first) or 19-fold (T first). With regard to environmental limit values, metal stability and organic carbon resources, sequential washing with different biosurfactants is a beneficial strategy for the remediation of smelter-contaminated soil with given properties.

  • 345.
    Gusiatin, Zygmunt Mariusz
    et al.
    Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Sloneczna 45G, 10-719 Olsztyn, Poland.
    Kumpiene, Jurate
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Janiszewska, Sylwia
    REMEA Sp. z o.o., Powazkowska 44c, 01-797 Warsaw, Poland.
    Kasiński, Sławomir
    Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Sloneczna 45G, 10-719 Olsztyn, Poland.
    Pecio, Mariusz
    The Main School of Fire Service, Slowackiego 52/54, 01-629 Warsaw, Poland.
    Piec, Robert
    The Main School of Fire Service, Slowackiego 52/54, 01-629 Warsaw, Poland.
    Radziemska, Maja
    Institute of Environmental Engineering, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland.
    A Mineral By-Product from Gasification of Poultry Feathers for Removing Cd from Highly Contaminated Synthetic Wastewater2020In: Minerals, E-ISSN 2075-163X, Vol. 10, no 12, article id 1048Article in journal (Refereed)
    Abstract [en]

    Ash from poultry feather gasification was investigated as an adsorbent for Cd removal from synthetic wastewater under a range of operational conditions: initial pH (2–8) and salinity (8–38 mS/cm) of wastewater, ash dosage (2.5–50 g/L), Cd concentration (25–800 mg/L) and contact time (5–720 min). The ash was highly alkaline and had low surface area and micropores averaging 1.12 nm in diameter. Chemical/mineralogical analysis revealed a high content of P2O5 (39.9 wt %) and CaO (35.5 wt %), and the presence of calcium phosphate, hydroxyapatite and calcium. It contained only trace amounts of heavy metals, BTEX, PAHs and PCBs, making it a safe mineral by-product. Cd adsorption was described best with Langmuir and pseudo-second order models. At pH 5, an ash dosage of 5 g/L, 40 min contact time and 100 mg Cd/L, 99% of Cd was removed from wastewater. The salinity did not affect Cd sorption. The maximum adsorption capacity of Cd was very high (126.6 mg/g). Surface precipitation was the main mechanism of Cd removal, possibly accompanied by ion exchange between Cd and Ca, coprecipitation of Cd with Ca-mineral components and Cd complexation with phosphate surface sites. Poultry ash effectively removes high concentrations of toxic Cd from wastewater.

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  • 346.
    Gustafson, Anna
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Schunnesson, Håkan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Jonsson, K.
    Luossavaara Kiirunavaara AB, Malmberget, Sweden.
    Draw point behavior in LKAB’s SLC mines2019In: Rock Mechanics for Natural Resources and Infrastructure Development - Full Papers: Proceedings of the 14th International Congress on Rock Mechanics and Rock Engineering (ISRM 2019), September 13-18, 2019, Foz do Iguassu, Brazil / [ed] Sergio A.B. da Fontoura; Ricardo Jose Rocca; José Pavón Mendoza, Taylor & Francis, 2019, p. 211-218Conference paper (Refereed)
    Abstract [en]

    In a sublevel caving mine, the ore recovery, side rock dilution and the total ore extraction rate are determined and controlled at the draw point. The decision to stop loading at a drawpoint and continue blasting the next fan is critical. Abandonment of the draw point too early leads to ore losses and inefficient use of ore resources. On the other hand, closing a draw point too late leads to increased side rock dilution and increased production costs. The purpose of this paper is to evaluate the used technique for draw control and the potential for increasing the loading level efficiency using available data sources as well as other types of information from the Luossavaara Kiirunavaara AB (LKAB) mines.

  • 347.
    Gustafsson, Markus
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering.
    Energier och CO2, fördelning i flödet vid mobil krossning2019Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [en]

    Due to new laws and the company’s own initiative concerning tracking of energies and emissions in quarries, NCC has begun surveying these factors. For their smaller quarries they mean to produce a method for local site managers, with which they themselves can perform this task. Because of these reasons the study in this rapport has been done. The end goal was to study the amount of available informtion about the energies at Eker quarry. Then Using this information to create a method for site managers to simplify their work as well as performing a survey in Eker concerning energies and emissions per ton of produced materials during 2018. The end product was an excel-file that calculates och distributes energies and emissions as long as data about used diesel and electricity is entered into the file. The survey produced the key figures for energies, 10,03 kWh/ton for the total 4,82 kWh/ton for products after the first crusher stage, 7,74 for products after the second and 14,25 kWh/ton for products after the third crusher stage. The key figures for emissions are 2,39 kg CO2/ton for the total, 1,05 kg CO2/ton for products after the first crusher stage, 1,80 for products after the second and 3,49 kg CO2/ton for products after the third crusher stage. The results show the possibilities to perform this type of survey with the produced method. The survey’s limitations were at the preliminary work with salvoes and ended when the product was loaded to a customer. Only the major factors of diesel and electricity was studied.

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  • 348. Gustavsson, Björn
    Estimating and reducing errors in soil sampling2004Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Contaminated sites are sampled and analysed to assess their remediation need. In the process the question arises if the results of the analysis represents the site they are taken from properly. Sampling and preparation is known to induce errors. Results from the analysis of soil samples may be expected to include errors. For a heterogeneous material like soil, much of the overall errors may be associated with the sampling and sample handling. To improve the reliability of the results, the sampling and preparation procedure need to be evaluated and improved. This thesis focus on how to estimate and reduce sampling errors. According to the Theory of Sampling (TOS), also known as Pierre Gy's Sampling Theory, the total sampling error is a sum of seven different errors. The theory describes how to calculate the uncertainty of some errors. It also describes how to reduce the errors. A case study were used for calculating the sampling error and make comparisons with the analytical error. Ways to reduce sampling errors are presented and discussed as application of TOS on the sampling of contaminated soil. The errors can be reduced by means like: Grinding or milling the samples Increase the sample size Taking several small increments to compose a sample Avoiding bias during sub-sampling through selection of equipment

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  • 349.
    Gustavsson, Björn
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Heterogeneities in samples of contaminated soil2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Many factors are important during sampling of contaminated soil. One of these is the sample sizes used. By estimation of the Heterogeneity Invariant (HI) it is possible to balance the sample size to one uncertainty contribution that is attached to sampling and sample handling. This is called the Fundamental error. Large overestimation of HI leads to larger samples and increased cost for sample handling. Large underestimation of HI leads to too small samples and to a larger uncertainty contribution, and possible skewed samples. Some methods to estimate HI is described and discussed from the perspective of contaminated soil sampling. Contaminated soil is a widely used concept, it is quite different challenges to sample if the contaminant is e.g. metallic particles, in-evaporated solutions or oils. None of the discussed methods is without any limitation. Field portable X-ray spectroscopy fluorescence is (XRF) is a popular instrument to analyse for metals in contaminated soils. It can provide quick and cheap analysis. The most prepared samples are dried, ground finely and put into Mylar thin film XRF sample cups. The sample volume is about 5-7 cm3, but the actually measured volume is only a fraction thereof. In the, likely, case of segregation in the sample volume this can lead to a biased measurement. Mechanisms for segregation in the XRF sample cup are discussed. Further suggestions are made to reduce the segregation. Despite precautions to reduce the effect of segregation it is difficult to eliminate it.

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  • 350. Gustavsson, Björn
    et al.
    Luthbom, Karin
    Ramböll Sverige AB, Luleå.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Comparison of analytical error and sampling error for contaminated soil2006In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 138, no 2, p. 252-260Article in journal (Refereed)
    Abstract [en]

    Investigation of soil from contaminated sites requires several sample handling steps that, most likely, will induce uncertainties in the sample. The theory of sampling describes seven sampling errors that can be calculated, estimated or discussed in order to get an idea of the size of the sampling uncertainties. With the aim of comparing the size of the analytical error to the total sampling error, these seven errors were applied, estimated and discussed, to a case study of a contaminated site. The manageable errors were summarized, showing a range of three orders of magnitudes between the examples. The comparisons show that the quotient between the total sampling error and the analytical error is larger than 20 in most calculation examples. Exceptions were samples taken in hot spots, where some components of the total sampling error get small and the analytical error gets large in comparison. Low concentration of contaminant, small extracted sample size and large particles in the sample contribute to the extent of uncertainty.

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