RISE – Research Institutes of Sweden
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Pilot scale succinic acid production from fibre sludge followed by the downstream processing
No full textThe utilization of a cheap side stream is the core for biotechnological production of platform chemicals, such as, succinic acid. This study explores lab and pilot scale fermentation of Actinobacillus succinogenes (B1) and Basfia succiniciproducens (B2) to produce succinic acid from sulphide fibre sludge, a side product from pulp and paper industry. Both strains demonstrated efficient SA production, with lag phase of 2–3 h, accompanied by by-product formation of formic acid (FA) and acetic acid (AA). B1 outperformed B2 in SA concentration (28.4 g∙L-1 vs 20.4 g∙L-1) and yield ( 0.76 g·g-1 and 0.51 g·g-1), leading to its selection for pilot scale fermentations. Pilot scale fermentations using SFS hydrolysate as carbon source achieved SA yields of 0.62–0.66 g/g with productivities of 0.65 – 0.78 g∙L-1 SA. SFS hydrolysate, rich in glucose provided a promising substrate, yielding 23 g∙L-1 SA. Two downstream processing (DSP) methds were evaluated for SA recovery. DSP 1, involving microfiltration, electrodialysis, and ion exchange, achieved 62 % recovery but incurred losses during filtration and electrodialysis. DSP2 utilized activated carbon for decolorization, followed by microfiltration and crystallization, yielding 60.3 % SA recovery. Both DSP approaches produced high purity SA suitable for polymer applications. These results underscore the potential of SFS hydrolysate for sustainable SA production and highlight the need for process optimization, including fed-batch or continuous systems, to enhance yields and reduce costs. These findings contribute to advancing biobased monomer production as a viable alternative to fossil-based methods. This work was supported by BIOMAC Project that received funding from the European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 952941.</p
Influence of Abuse Methods on Thermal Runaway in Lithium-Ion Cells : Measured Heats from Battery, Jet Flame, and Oxygen Depletion Calorimetry
No full textThe amount of heat generated during thermal runaway in lithium-ion cells is dependent on the failure mechanism and abuse method. This study determines the heats generated inside and outside a 64 Ah lithium-ion pouch cell when it is forced into thermal runaway by nail penetration, heating, or overcharging. The generated heats were determined by battery calorimetry, jet flame calorimetry, and oxygen depletion calorimetry. The ratio between heat generated inside or outside the cell is found to be dependent on the abuse method. The overcharge experiment was most severe with respect to heat generated outside the cell, with 89% more thermal energy measured by the jet flame calorimeter compared to nail penetration. For heat generated inside the cell it was opposite, where nail penetration was the most severe with 53% more thermal heat generated compared to overcharge. We explain these differences from the cell mass losses during thermal runaway. When the cell mass loss increases, the heat generated outside the cell increases and simultaneously the internal heat generation decreases. For the safety of a battery module, these results imply that the possibility for propagation of a thermal runaway between cells is dependent on failure mechanism.This work was part of the BattMarine project (project number281005) and 2ND LIFE project (project number 320760), funded bythe Research Council of Norway and Norwegian industry. Thecompletion of the manuscript has received funding from the FireResearch and Innovation Centre (FRIC), which is funded by itspartners, the Research Council of Norway (programBRANNSIKKERHET, project number 294649) and the GjensidigeFoundation.</p
Micro-focused X-ray diffraction imaging analysis of Fe nitrides and carbides in the compound layer of nitrocarburized and gas nitrided steel surfaces
No full textThermochemical treatments like nitrocarburizing and gas nitriding form hardened surface layers of iron nitrides and carbides, improving wear, fatigue, and corrosion resistance in loaded components made of steel. This study employs micro-focused X-ray diffraction (µXRD) imaging at a synchrotron facility to characterize the microstructure of nitrocarburized and gas-nitrided steel surfaces in three steel grades (46MnVS3, 34CrNiMo6, 16CrMnNiMo9–5–2). Through line profile analysis with fine-step mesh grid scanning, we spatially resolve phase distributions and elastic strains in the compound layer. The ε-phase exhibits isotropic residual strain, transitioning from expansion to compression with depth, while the γ’-phase displays anisotropic strain, expanding perpendicular to the surface and compressing parallel to it. These findings highlight µXRD’s potential for detailed structural analysis, enabling optimization of surface hardening processes
Modelling a Damper-Optimized Demand Control Ventilation System During a Fire
No full textModern heating, ventilation, and air conditioning (HVAC) systems have evolved from simple on-off, fan-driven systems to highly complex, energy-optimized systems involving sensors monitoring the building whose outputs result in dynamic changes to the HVAC system operation. In some buildings, the HVAC system is intended to aid in smoke and pressure control during the event of a fire. In such a case, the smoke, heat, and pressure from fire growth and spread interact with the HVAC system, while the control logic may react to the fire alarm and increase ventilation rates. A series of tests investigating the performance of modern damper-optimized demand control ventilation (DCV) systems during a fire and its effect on smoke and pressure control was recently performed. This paper examines the ability of Fire Dynamics Simulator (FDS) to model a DCV HVAC system undergoing a dynamic response change due to the presence of fire. Results show that the FDS HVAC model is capable of such simulations. However, there were challenges in the modelling process due to the limitations on the experimental data obtained from the real-world building management system software. A path forward for more complete simulations is identified. Funding for RISE Fire Research came from the project "BRAVENT - Efficient smoke ventilation of small fires", which is funded by the Research Council of Norway, grant no. 321099 and its project partners.</p
The Impact of Water-Based Fire Suppression Systems on Combustion Products
No full textThis study aims to experimentally investigate the combustion products of fires suppressed/extinguished by two water-based fire suppression systems, namely, sprinklers and water mist systems. A total of thirteen experiments were conducted with various suppression system configurations, i.e., with a sprinkler, a low-pressure (LP) water mist, and a high-pressure (HP) water mist, at operating pressures ranging from 2 to 60 bar and water flow rate ranging from 10 to 206 L/min. Each experiment was conducted twice, except for the baseline experiment with no suppression. The fuel was a high-density polyethylene (HDPE) pallet placed on two wood pallets. During all the stages of fire development, suppression with water, and post-suppression, the combustion products were sampled through Fourier-Transform Infrared Spectroscopy (FTIR) using a gas analyzer capable of operating in high humidity. The main combustion products identified were CO2, CO, and H2O. In addition, NOx (nitrogen oxides), CxHy (light-weight hydrocarbons), and HCN were present in relatively high concentrations. All the tested fire suppression systems were effective in reducing the fire size and cooling down the gases. However, when the fire could not be immediately extinguished, the NOx, CxHy, and HCN concentrations were higher than those in the baseline experiment. Moreover, it is observed that the HP water mist system was more effective than the sprinkler and low-pressure water mist systems in reducing the amount of combustion gases during suppression, resulting in lower Fractional Effective Doses (FED). It was observed that the combustion products returned to ambient conditions after five minutes of deactivation. The results from this study provide much-needed validation data for the effectiveness of water-based suppression systems, not only in reducing the fire size but also in reducing the production of acute toxic gases, which is important for considerations regarding evacuation, firefighting, and post-extinguishment conditions. .This research is with the support from the Fire Research and Innovation Centre(FRIC) funded by the Research Council of Norway (No. 294649).</p
Development of a prototype for measuring the fuel consumption of ocean-going ships
No full textThe maritime sector is working hard to reduce greenhouse gas emissions. Overall, the shipping industry is under considerable pressure to identify innovative solutions, including a transition from conventional to cleaner fuels by 2050. The most promising future fuels are ammonia, ethanol and methanol, which have lower viscosities than current fuels. These new generation fuels are sustainable and have the potential to significantly reduce greenhouse gas emissions. Positive displacement meters are one of the most common types of flow meters used to measure fuel in the marine sector. However, they usually require a certain viscosity to perform properly. The aim of this study is to investigate the measurement performance of a prototype positive displacement fuel consumption meter capable of measuring next generation marine fuels and fuel blends with these and established fuels. The paper outlines the development of the prototype and how it was subsequently improved. Measurements were carried out on the prototype with fuels of different viscosities and line pressures relevant to shipping. The results prove that the meter operates almost independently of viscosity and pressure, making it suitable to accurately measure today’s (current fuels), tomorrow’s (blended fuels) and future fuels. Finally, suggestions for further improvements are given. This project (EMPIR JRP 20IND13 SAFEST) has received funding from the EMPIR programme co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation programme.</p
VHGgods : Var sker godstransportsektorns framtida växthusgasutsläpp?
No full textTriple F projekt 2022.5.2.3</p
En guide för partssamverkan vid kriser och osäkerheter
No full textInspirationsguiden bygger på praktiska erfarenheter från COVID-19 pandemin. De belyser arbetsplatser i olika sektorer och speglar olika scenarier där organisationer snabbt har behövt skalat upp eller skalat ner kritiska arbetspraktiker. Guiden är uppdelade utifrån nyckelfaktorerna i vår vägledande modell och är strukturerad i tre delar: Förutsättningar – nr. 1-4, Scenarier – nr. 5- 12 och Processer – nr. 13-14. Efter varje scenario finns ett antal reflektionsfrågor som är tänkta att stödja en gemensam analys och utvärdering av er egen verksamhet i förhållande till de utmaningar och lärdomar som scenariot beskriver. Genom att diskutera dessa frågor kan ni identifiera styrkor och utvecklingsområden, samt förbättra er beredskap för framtida förändringar och kriserGuiden bygger på forskning i projektet Spin-Off som finansieras av Afa Försäkring. I projektet har vi studerat olika typer av organisatoriska förändringsprocesser under och efter Covid-19 pandemin.</p
INFLUENCE OF GLASS BREAKAGE ON VENTILATION AND FIRE BEHAVIOUR IN LARGE TIMBER COMPARTMENTS: A NUMERICAL SIMULATION STUDY
No full textFlexibility-centric sizing and optimal operation of building-thermal energy storage systems : A systematic modelling, optimization and validation approach
No full textThe increasing integration of renewable energy sources (RES) and the transition towards a decarbonized energy sector present significant challenges, particularly in demand-side management. Thermal energy storage (TES) systems offer a cost-effective solution for enhancing energy flexibility in building heating systems. However, improper sizing and operation of TES systems can lead to increased investment costs and energy losses. To bridge this gap, this study proposes a novel, optimization-based framework for the systematic sizing and operation of TES systems. The methodology encompasses two key components: (1) an innovative TES sizing framework that integrates system modelling and optimization-based sizing leveraging historical thermal load data; (2) validation and performance evaluation of the sizing outputs through building energy simulations across three diverse building types and climatic conditions. Key findings demonstrate the framework’s ability to adapt to various scenarios, achieving operational cost reductions of up to 35 % and significantly enhancing the energy flexibility in terms of flexibility factor by up to 1.03. Furthermore, the proposed framework is shown to effectively optimize TES capacities to unique building load patterns. These results highlight the framework’s potential as a robust tool for optimizing TES in buildings, contributing to flexible and cost-efficient energy systems. This work was supported by the Swedish Energy Agency under Grant number 51544-1 and the European Union’s H2020 program under Grant number 101096789.</p