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HCT City : Omvärldsanalys och prioriteringar för effektivare masstransporter i städer
No full textDenna rapport är resultatet av arbetspaket 2: Omvärldsanalys och prioriteringar inom projektet HCT City: Fallstudie massgods i städer, finansierats av Vinnova. Arbetet har utförts mellan 2021 och 2024. Syftet med hela projektet har varit att undersöka potentialen för High Capacity Transport (HCT) i urban miljö, med särskilt fokus på masstransporter av schaktmassor. Bygg- och anläggningstransporter står för cirka 20 % av Sveriges totala transportarbete och 50 % av transportarbetet i städer (viktmässigt). Trots detta har området tidigare varit under utforskat. Projektet fokuserar på fyra huvudområden: infrastruktur, fordon, tillträdeskontroll inklusive samlat regelverk och tillsyn samt digitalisering och koordinering av byggprocessen. Omvärldsanalysen omfattar internationella erfarenheter, särskilt från Finland, Danmark, Australien och Sydafrika. Finland har varit föregångare med införandet av 76-tons fordon och uppnått betydande minskningar i CO₂-utsläpp och transportarbete. I Sverige tillåts nu längre fordonskombinationer på upp till 34,5 meter och 74 ton (BK4), vilket ger möjligheter till effektivare transporter, dock med varierande tillgång till sådant vägnät i kommunerna. Rapporten ger också en nulägesbeskrivning av nuläget i Sverige avseende HCT för masstransporter. En viktig del av omvärldsanalysen är en intervjustudie från Finland som undersöker införandet av HCT med fokus på masstransporter i städer. Intervjustudien undersöker hur man löst regelverk och tillgänglighet, fordon och infrastruktur i Finland samt erfarenheter från detta. Dessutom beskrivs pågående automatisering och digitalisering av massahantering i Helsingfors med hjälp av flera digitala verktyg och plattformar. Även digitalisering av transportdokument håller på att implementeras (2022) Trafikarbetet har minskat samtidigt som att transportarbete ökat i Finland tack vare regelförändring och implementering av HCT-koncept under perioden 2014-2021 i takt med att fordonsparken successivt blir effektivare visar statistik. Syftet med omvärldsanalysen var dels att lära av andra goda exempel, dels att få hjälp med prioriteringar inom projektet och fallstudierna kring viktiga frågor att utreda inom projektet. Arbetet har varit iterativt och lärdomar från detta arbetspaket har successivt tagits tillvara i arbetet i de olika arbetspaketen i projektet. Sammanfattningsvis visar omvärldsstudien att HCT i urban miljö kan leda till betydande miljövinster, ökad transporteffektivitet och förbättrad trafiksäkerhet, förutsatt att infrastrukturella och regelmässiga hinder hanteras. Rapporten identifierar behovet av ett sammanhållet vägnät med samordnade regler över kommun- och regiongränser för att möjliggöra bredare implementering av HCT i städer. Utmaningar kvarstår i form av varierande bärighetsklassning, olika kommunala prioriteringar samt behov av fortsatt forskning ochRapporten är framtagen med ekonomiskt bidrag från Vinnova FFI.</p
Ash Transformation Processes during Pulverized Fuel Combustion of Rice Husks
No full textRice husks were combusted in a 150 kW pilot-scale powder burner connected to a horizontal ceramic-lined furnace to investigate the ash transformation processes, including deposit formation at high surface temperatures. Residual coarse ash samples (>1 μm) were collected from different positions along the furnace and heat exchanger path. Fine fly ash samples (<1 μm) were collected from the furnace outside the flame, and high-temperature deposits were collected on deposition probes having different surface temperatures. The collected samples were analyzed via scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. Additionally, thermodynamic equilibrium calculations were employed to interpret experimental results. The results showed different ash transformation processes occurring at the outer surface and inner part of the rice husks. A high share of minor ash-forming elements (i.e., K, P, Ca, and Mg) together with Si was retained in the residual coarse ash particles. The retained minor ash-forming elements were mainly incorporated in the spherical Si-rich particles with moderate amounts of K, Ca, Mg, and P that were partially molten and originated from the inner part of the rice husks. The outer surface of the rice husks primarily formed skeleton-like coarse ash particles dominated by Si. The high surface temperature deposits only contained skeleton-like coarse ash particles that were partially molten. The authors gratefully acknowledge the funding provided bythe Swedish Energy Agency, project no. 46443-2.</p
Degradation of polyester coil-coated materials by accelerated weathering investigated by FTIR-ATR chemical imaging and impedance analysis
No full textIn the present study, ex situ Fourier transform infrared (FTIR) chemical imaging and in situ electrochemical impedance spectroscopy (EIS) were combined to investigate the ageing process of a polyester/melamine coil-coated steel. The samples were first subjected to a QUV accelerated weathering test for 250 h up to 2000 h, followed by immersion in a 0.5 M NaCl solution to assess water uptake and polymer matrix plasticization. FTIR analyses revealed chemical degradation, including chain scission and the formation of polar groups, between 500 h and 2000 h of QUV exposure. Degradation effects were observed throughout the whole topcoat, with more significant degradation occurring near the surface. EIS measurements indicated greater water uptake with increasing QUV exposure, highlighting two regions of water sorption: an initial rapid Fickian diffusion region and a slower non-Fickian region. The time constant (τ) analysis, which was extracted from the EIS data and related to the dielectric manifestation of the glass transition, confirmed polymer matrix plasticization due to water uptake. Despite UV-induced degradation, the polymer maintained effective protective properties, as evidenced by the high low-frequency impedance unaffected by UV exposure or immersion duration (1 week). This methodology successfully identified ageing markers, providing a framework for studying UV degradation mechanisms, water uptake, and polymer mobility in anticorrosion coatings. This work has been partially funded by the Swedish Foundation for Strategic Research (SSF) grant number FID18-0034 and the Member Research Consortium on Coil Coated Materials. </p
Simulation and Emulationof Water spray for Validation of Optical Sensors (SEVVOS)
No full textThis research investigated visibility degradation caused by vehicle-generated water sprayon wet surfaces, using experimental tests, simulations, and data analysis to examine spraydynamics and their effects on camera and sensor performance.Dynamic tests faced challenges with automated contrast analysis due to insufficientresolution, lack of camera calibration, and poor lighting. Targets were too small inimages, and low contrast, even without spray, prevented reliable detection. Similar issuesaffected static tests, although higher light levels enabled more consistent results. Highbeamheadlights worsened contrast degradation by illuminating spray particles. Thesefindings emphasized the importance of proper calibration, resolution, and lighting foraccurate data collection.Outdoor tests on AstaZero test tracks showed that water depth and vehicle speedsignificantly influence spray and visibility. Deeper water (e.g., 9–10 mm) caused greatercontrast degradation than shallower water (e.g., 4–5 mm), while higher speeds amplifiedspray effects, particularly in shallow water. Variations in light conditions affected theresults, with clearer patterns emerging under stable lighting.Tyre rig tests provided detailed measurements of aerosol and water spray properties, suchas droplet size, density, and distribution. Smaller droplets (mode below 50 μm) formednear the tyre surface, while larger droplets developed downstream due to coalescence andaerodynamic forces. Higher tyre speeds and more water increased spray density andcontrast degradation. In deeper water, contrast degradation was more uniform, withnarrower ranges between maximum and minimum values.Simulations revealed key mechanisms of spray generation and propagation. Water filmdepths as low as 100 μm produced spray through capillary adhesion, with dropletsinteracting with vehicle components and airflow. Larger droplets returned to the groundquickly, while smaller droplets remained suspended, affecting visibility. Data collectedunder naturalistic conditions validated these findings and provided insights into realworldvisibility challenges.This research highlights the critical role of water depth, vehicle speed, and spraydynamics in visibility degradation. It underscores the need for improved measuringmethods, lighting, and testing protocols to enhance automated analysis and sensorperformance, especially for autonomous vehicle systems in adverse weather conditions.FFI, Strategic Vehicle Research and Innovation, is a joint program between the state and the automotiveindustry running since 2009. FFI promotes and finances research and innovation to sustainable roadtransport.Simulation and Emulation of Water spray for Validation of Optical Sensors (SEVVOS
Simulation of weather effects when baling cereal straw with high water contents.
No full textDet övergripande målet med denna studie var att undersöka och kvantifiera hur tillgången på pressad halm och dess årliga variation påverkas om man tillåter pressning vid förhöjd vattenhalt. Studien är en del av projektet “Smart lagring och förbehandling av halm till bioraffinaderi ”och gjordes för fyra viktiga odlingsområden i Sverige, nämligen Västmanland, Östergötland, Västra Götaland och Skåne. Om halmen bärgas vid en högre vattenhalt än brukligt ökar den tillgängliga tiden för pressning, dels eftersom det finns fler timmar där halmen håller en accepterad vattenhalt, dels eftersom den dagliga arbetstiden kan utökas morgon och kväll. Detta skulle ge jämnare tillgång på halm mellan år och en större andel av halmen skulle kunna bärgas, särskilt under år med ogynnsam väderlek. Det skulle också kunna sänka de fasta maskinkostnaderna per mängd bärgad halm och spannmålsfälten skulle också bli tillgängliga tidigare på hösten och därmed göra halmbärgningen mer attraktiv för lant-brukarna. Ytterligare en fördel med att bärga halmen lite fuktigare kan vara att aktiviteten av naturligt förekommande mikroorganismer under lagringen ger en förbehandling som kan vara positivt för efterföljande processer i bioraffinaderier. Detta undersöktes i en annan del av projektet. Med hjälp av simuleringsmodeller och historiska väderleksdata från 27/28 år (1995/1996–2022) beräknades vattenhalt på timbasis för både spannmålskärnan i den stående grödan och för halmen i strängen. Skördetröskning och halmpressning simulerades med en annan modell där de uppskattade vattenhalterna användes som indata. Tillgången till balpressar i ett område påverkar hur mycket halm som kan bärgas/pressas, speciellt under år med dåliga väderförhållanden. För att återspegla detta gjordes beräkningar där betinget för en balpress varierade, dvs. den halmmängd varje press ska pressa per säsong. Andel pressad halmmängd per år beräknades för 3 000, 5 000 respektive 7 000 ton per år bärgningsbar halmmängd vid 18 % vattenhalt (v.b.) dvs. ett litet, medelstort respektive stort beting. Den pressade andelen uppskattades för varje beting och område med 18, 20, 25, 30 0ch 35 % (v.b.) som maximal vattenhalt för balning. Den dagliga tröskkapaciteten sattes till 10 % av spannmålsarealen, presskapaciteten för halm till 13 ton/timme (inklusive ställtid och andra avbrott), arbetstiden till kl. 7-23 och pressningsperioden fram till mitten av september. De bärgningsbara halmmängderna per hektar beräknades utifrån normskördar för respektive område och halm/kärna-kvoter. Halmgrödornas arealfördelning på de simulerade gårdarna motsvarade deras arealfördelning för respektive län. De mest relevanta iakttagelserna/slutsatserna för de fyra områdena med de ovanstående pressningsförutsättningarna var: • med tilltagande maximal vattenhalt för pressning ökade den tillgängliga pressnings-tiden under augusti och september betydligt, från ca 35 % till ca 70 % vid 18 % respektive 35 % maximal vattenhalt för pressning; • behovet av balpressar varierar mycket mellan år på grund av vädervariationer m.m. För att ha ett pressningssystem där en hög andel halm kan pressas varje år bör varje press ha ett beting på 3000-5000 ton/år; • ett till två år av tio minskade andelen pressad halmmängd med 30 % eller mer, till och med för det lilla betinget och 35 % maximal vattenhalt för pressning; • den genomsnittliga vattenhalten i den pressade halmen var betydligt lägre än de maximala tillåtna vattenhalterna för pressning; • andel pressad halmmängd minskade med ca 20 % eller mer under några få år (ca 5 % av åren) då en del av arealen inte kunde tröskas p.g.a. ogynnsam väderlek; • ovanstående resultat uppvisade inga stora skillnader mellan de fyra områden som ingick i studien.The study aimed to investigate and quantify how baled straw availability, and its annual variation are influenced by allowing baling at higher moisture contents than usual. It focused on four key cereal-producing counties in Sweden: Västmanland, Östergötland, Västra Götaland and Skåne. Baling straw at higher moisture content extends the available working hours by allowing operations earlier in the morning and later in the evening, as well as increasing the number of hours when straw maintains an acceptable moisture level. This could lead to a more stable annual straw supply and higher harvestable volumes, particularly in years with adverse weather conditions. Additionally, it may reduce fixed machinery costs per unit of baled straw and free up grain fields earlier in the autumn, making straw harvesting more appealing to farmers. Moreover, baling straw with higher moisture content might allow natural microbial activity to initiate a pre-treatment process during storage, which could be beneficial for biorefineries. This aspect was explored further in another part of the project. Using simulation models and historical weather data spanning 27/28 years (1995/1996–2022), the hourly grain moisture content of pre-harvested cereals and swathed straw was estimated. These values were then applied to a model simulating threshing and baling operations over multiple years. Since the availability of balers in a region influences how much straw can be baled/collected, calculations were performed under different baling conditions. Annual baled straw ratios were estimated for balers with harvest capacities of 3000, 5000 and 7000 tons per year (at 18% moisture content (wet basis), with maximum bailing moisture contents set at 18%, 20%, 25%, 30% and 35% (w.b.). The simulation model assumed a daily grain harvesting capacity of 10% of the cereal area, a baling capacity of 13 tons/hour (including downtime), working hours from 7:00 to 23:00, and a bailing period extending until mid-September. Harvestable straw amounts per hectare were based on standard straw-to-grain ratios specific to each county: 0.6 for winter wheat, 0.66 for spring wheat, 0.37 for spring barley, and 0.52 for oats. The simulated cereal area distribution reflected the actual proportions in each county. The key findings from the study with the above baling conditions were: • Increasing the maximum permissible moisture content for baling significantly extended available baling time in August and September, from approximately 35% at 18% moisture to around 70% at 35% moisture. • Baling capacity requirements varied substantially between years due to weather fluctuations. To ensure a consistently high proportion of baled straw, the optimal harvestable straw volume should be between 3000 and 5000 ton/year. • In one to two years out of ten, the amount of baled straw decreased by 30% or more, even when bailing at 35% moisture content and 3000 tons of harvestable straw per year. • The average moisture content of the baled straw remained significantly lower than the maximum permissible moisture levels. • In about 5% of the years, extreme weather prevented threshing in parts of the straw crop area, reducing the baled straw ratio by approximately 20% or more. • Regional differences among the studied counties were minimal.Arbetet utfördes inom ramen för projektet Smart lagring och tillförsel av halm till bioraffinaderi som finansierats av Energimyndigheten.</p
Modal analysis and superposition for dynamic response of structures with discontinuities using HybriDFEM
No full textThe dynamic characterization of structures using discrete models, as well as the application of modal superposition to compute their dynamic response, has been rarely explored in the literature. This is at odds with the international relevance of discrete models in structural assessment, and the multiple fields of application of modal analysis and superposition, from structural health monitoring to seismic engineering. This paper introduces a 2D discrete formulation, developed within a finite element framework, to address this gap. Initially conceived for nonlinear static analyses as HybriDFEM (Hybrid Discrete-Finite Element Method), it is now augmented with a procedure to compute the mass matrix, natural frequencies, mode shapes, and response-related quantities such as modal and dynamic contribution factors or effective modal mass. Moreover, using the structural tangent stiffness matrix in the eigenvalue problem allows tracking the evolution of natural frequencies and modes in structures loaded into their nonlinear material and geometric range. The formulation is validated through several examples, where it compares well with results from engineering beam theories, refined finite element models, and numerical time-integration methods. In an application example studying the evolution of modal properties of a progressively damaged frame, HybriDFEM is coupled with finite elements, highlighting its novel approach to integrating discrete and finite elements for enhanced structural modal analysis and superposition.The first author is thankful for the financial support given by UCLouvain</p
Reshaping roles and value logics among distributed system operators for future electricity systems
No full textBackground: This paper seeks to explore the roles of distribution system operators (DSOs) in future energy systems. Measures to combat climate change have led to a transition in the energy sector, where old system fundamentals are becoming obsolete, which results in changing rules for incumbent actors, such as DSOs. These actors must uphold heavily regulated operations within their distribution networks, while landscape trends are changing with a growing number of prosumers and distributed energy resources. To understand these future roles and increase the preparedness for future scenarios and facilitate thinking beyond current lock-ins, action-oriented workshops were held with two Swedish DSOs, departing from pre-developed future imaginaries, structured through transition theory. Researchers were actively involved in the workshops, to guide the participants in the discussions and to provide additional knowledge from transition processes. This was structured through transition theory, mainly in terms of linking transition management fundamentals to the topics in the workshops and basing the workshop discussions on an imagined future socio-technical system-wide approach using four focus areas. Results: Results included descriptions of roles within future energy systems and their connection to specified value logics from different target groups which would, from the DSO perspective, create value in a future energy system. Roles included sustainable developer, facilitator for increased collaboration, balancing actor, and communicator. In addition, competence requirements were outlined concerning the described roles. The future logic was also described in a conceptual value model for an active DSO in a prosumer-oriented energy system, creating value in all different value logics. Moreover, it provided the steps necessary to develop a pathway aimed at the transformation of DSOs. Conclusions: The study provided a constructive approach for DSOs to prepare for a future, more prosumer-oriented and flexible energy system, avoiding being locked in current system thinking and focusing on necessary roles and competencies suitable for a DSO. In addition, the utilization of the value logics approach helped place the prosumers in a differentiated manner, which can have implications for strategies among DSOs to create the necessary relations and collaborations for an efficient and value-creating future energy system. Open access funding provided by RISE Research Institutes of Sweden. Funded by the European Commission in the UNITED–GRID project under Grant agreement ID: 773717.</p
Targeting aleurone cells for enhanced protein recovery from wheat bran : Impact on protein functionality and phytate content
No full textProtein extraction from wheat bran is challenging due to its multi-layer and fiber-rich structure. Here, opening aleurone cells, via dry and wet milling, their combination and a novel ultrafine milling, and its effect on wheat bran’s protein recovery using the alkaline solubilization/isoelectric precipitation and protein structure, functionality, and phytate content were investigated. Wet milling and ultrafine milling improved protein recovery and purity but only ultrafine milling reduced bran particle size to the aleurone cells and exposed their structure. Despite this, ultrafine milling did not significantly increase protein yield compared to wet milling, which partially opened the aleurone cells, meaning that opening the cells per se is not enough for extracting their protein. Proteins extracted with the aid of ultrafine milling had smaller particle sizes with significantly better water solubility (>2-fold) and rheological properties. Both wet milling and ultrafine milling significantly improved the removal of phytate during the wet fractionation process. Altogether, optimizing milling techniques offers a promising path to enhance accessibility to wheat bran proteins and their quality if carefully fine-tuned but other assistant technologies are necessary for boosting the recovery of the released protein from aleurone cells. We are grateful to FORMAS for the research grant within the 3DMix project (grant number: 2021-02349)</p
Dust Explosion Risks in Battery Recycling
No full textCombustible dust hazards remain a persistent threat across various industries, as dust is an inevitable byproduct of many processes. Managing combustible dust hazards at the battery recycling plants is one of the key factors to minimize the incidents and down time and, therefore, to improve the work environment, and to increase the profitability of the business. The present work aims at exploring the dust explosion risks of black mass in battery recycling. Four black mass samples are investigated. Microscope images, particle size distribution, water content and organic carbonates are analyzed. Dust explosion experiments are performed in a 20-L vessel. Results show that a 10 kJ ignition energy cannot generate high explosion overpressure, whereas an ignition energy of 20 kJ yields an explosion overpressure above 6 bar. The experimental results are compared with published data on various explosion-related characteristics of other dusts in battery recycling, in particular, aluminum and graphite dusts.The Swedish Energy Agency is greatly acknowledged through SafeDust ReLIB project (number P2023-00060).</p
Simulation of Thermal Propagation in a Large Battery Module
No full textA multi-physics thermal propagation model of a battery module, consisting of 507 cylindrical 18650 cells, was built using a commercial software. The model incorporated an empirical method for self-heating in battery cells, a 3-Dimentional (3-D) Finite Element method (FEM) for simulating thermal propagation in solid materials, and sub-models for thermal convection and radiation. Simulations reveal the significance of thermal convection in thermal propagation. The model agreed well with the experimental data until around half of the cells entered thermal runaway (around 22 minutes), with an observed overprediction of heat release afterward. This overprediction might be attributed to inaccuracies in thermal convection and the omission of burning vented gases and solid particles.The Swedish Transport Administration and Stiftelsen Sveriges Sjömanshus are acknowledged through projectCarbon diOxide Fire Fighting Experimental Evaluation (number TRV 2023/33910 and FOU23-0016).</p