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  • 51.
    Dodoo, Ambrose
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Tettey, Uniben Yao Ayikoe
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Final energy savings and cost-effectiveness of deep energy renovation of a multi-storey residential building2017In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 135, p. 563-576Article in journal (Refereed)
    Abstract [en]

    In this study we present a method for analysis of cost-effectiveness of end-use energy efficiency measures and demonstrate its application for modelling a wide range of energy renovation measures for a typical 1970s multi-family building in Sweden. The method integrates energy balance and bottom-up economic calculations considering total and marginal investment costs of energy efficiency measures as well as net present value of total and marginal savings of the measures. The energy renovation measures explored include additional insulation to basement walls, exterior walls, and attic floor, improved new windows, efficient electric appliances and lighting, efficient water taps, glazed enclosed balcony systems, and exhaust air ventilation heat recovery systems. The measures are analysed first individually and then designed to form economic packages. Our results show that improved windows give the biggest single final energy savings while resource-efficient taps is the most cost-effective measure for the building. We find that the cost-effectiveness of the energy renovation measures is sensitive to real discount rates and energy price increases. Cost-optimal final heat savings varies between 34% and 51%, depending on the choice of real discount rate and energy price increase. The corresponding electricity savings varies between 35% and 43%. This study shows a method and the significance of various technical and economic-related parameters in achieving deep energy savings cost-efficiently.

  • 52.
    Dodoo, Ambrose
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Tettey, Uniben Yao Ayikoe
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Life cycle primary energy use of nearly-zero energy building and low-energy building2017In: ECEEE 2017 Summer Study: Consumption, Efficiency & Limits, European Council for an Energy Efficient Economy (ECEEE), 2017, p. 1075-1081Conference paper (Refereed)
    Abstract [en]

    Energy legislations are increasingly driving towards buildings with very low operation final energy use as part of efforts to reduce energy use and climate impact of the built environment. In this study we analyse the life cycle primary energy use of a recently constructed Swedish conventional 6-storey apartment building and compare it to variants designed as nearly-zero energy building or as low-energy building with a combination of improved thermal envelope and passive design strategies. We maintain the architectural design of the constructed building and improve the thermal properties of the envelope to achieve a low-energy building and also nearly-zero energy building including solar thermal collectors. We consider scenarios where the building variants are heated with renewable energy using cogenerated district heating, also complemented with solar heating system. We follow the life cycle of the building versions and analyse their total primary energy use, considering the production, operation and end-of-life phases. The results show that the relative significance of the production phase increases as buildings are made to achieve very low operational energy use. The production phase accounts for 17 % of the total primary energy use for production, operation and demolition of the constructed building for a 50-year lifespan. The corresponding values for the nearly-zero energy and low-energy building variants ranges between 30 to 31 %. Overall, the life cycle primary energy use for the nearly-zero energy and low-energy building variants are about 30–35 % lower compared to the constructed building.

  • 53.
    Dodoo, Ambrose
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Primary energy benefits of cost-effective energy renovation of a district heated multi-family building under different energy supply systems2018In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 143, p. 69-90Article in journal (Refereed)
    Abstract [en]

    The European Union's Directive on energy performance of buildings emphasizes the need to take cost-effectiveness into account when measures are implemented for improved building energy efficiency. In this study, we investigate cost-effective energy renovation measures for a district heated building under different contexts, including varied locations, energy supply systems and economic scenarios. We determine the final and primary energy savings of cost-effective energy renovation packages for the building in the different contexts. The measures analysed include: improved insulation for attic floor, basement walls, and exterior walls; improved windows and doors; resource-efficient taps; heat recovery of exhaust ventilation air; energy-efficient household appliances and lighting. We consider three existing Swedish energy supply systems of varying district heat production scale and tariffs, and also plausible renewable-based energy supply systems. Our analysis calculates the final energy savings of the measures including the cost-effective renovation packages on hourly basis and links these to the different energy supply systems. The cost-effectiveness analysis is based on a double-stage optimization method, considering total and marginal investment costs of renovation measures as well as associated net present values of total and marginal cost savings. The results show that significant final and primary energy savings can be achieved when energy renovation measures are implemented for the building in the different contexts. This study shows that heat demand in existing Swedish building could be about halved while electricity use may be reduced considerably with cost-effective energy renovation measures. The economic viability of the renovation measures is sensitive to the economic regimes especially discount rates and energy price increase.

  • 54.
    Dodoo, Ambrose
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Tettey, Uniben Yao Ayikoe
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Energy Simulation of Existing Swedish Multi-Storey Apartment Building in Växjö: Work Package 2, Task 2.1, carried out by UNI-SE in the Ready Project2016Report (Other academic)
  • 55.
    Dodoo, Ambrose
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Tettey, Uniben Yao Ayikoe
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Impacts of Common Simulation Assumptions in Sweden on Modelled Energy Balance of a Multi-family Building.2019In: Cold Climate HVAC 2018 / [ed] Johansson D., Bagge H., Wahlström Å., Springer, 2019, p. 689-699Conference paper (Refereed)
    Abstract [en]

    Here, we explore key input parameters and common assumptions for energy balance analysis of residential buildings in Sweden and assess their impacts on simulated energy demand of a building. Our analysis is based on dynamic hour-by-hour energy balance modelling of a typical Swedish multi-storey residential building constructed in 1972. The simulation input parameters studied are related to microclimate, building envelope, occupancy behaviour, ventilation, electric and persons heat gains. The results show that assumed indoor temperature set points, internal heat gains and efficiency of ventilation heat recovery systems have significant impact on the simulated energy demand. For microclimate parameters, the outdoor temperature, ground solar reflection and window shading gave significant variations in the simulated space heating and cooling demands. We found that input parameter values and assumptions used for building energy simulation vary significantly in the Swedish context, giving considerably different estimated annual final energy demands for the analysed building. Overall, the estimated annual final space heating demand of the building varied between 50 and 125 kWh/m2 depending on the simulation dataset used. This study suggests that site-specific parameter values may be appropriate for accurate analysis of a building’s energy performance to reduce data input uncertainties, as such factors may have a significant impact on building energy balance and energy savings of retrofit measures.

  • 56.
    Dodoo, Ambrose
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Tettey, Uniben Yao Ayikoe
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Influence of simulation assumptions and input parameters on energy balance calculations of residential buildings2017In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 120, no 1, p. 718-730Article in journal (Refereed)
    Abstract [en]

    In this study, we modelled the influence of different simulation assumptions on energy balances of two variants of a residential building, comprising the building in its existing state and with energy-efficient improvements. We explored how selected parameter combinations and variations affect the energy balances of the building configurations. The selected parameters encompass outdoor microclimate, building thermal envelope and household electrical equipment including technical installations. Our modelling takes into account hourly as well as seasonal profiles of different internal heat gains. The results suggest that the impact of parameter interactions on calculated space heating of buildings is somewhat small and relatively more noticeable for an energy-efficient building in contrast to a conventional building. We find that the influence of parameters combinations is more apparent as more individual parameters are varied. The simulations show that a building's calculated space heating demand is significantly influenced by how heat gains from electrical equipment are modelled. For the analyzed building versions, calculated final energy for space heating differs by 9-14 kWh/m(2) depending on the assumed energy efficiency level for electrical equipment. The influence of electrical equipment on calculated final space heating is proportionally more significant for an energy-efficient building compared to a conventional building. This study shows the influence of different simulation assumptions and parameter combinations when varied simultaneously. (C) 2016 Elsevier Ltd. All rights reserved.

  • 57.
    Dodoo, Ambrose
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Tettey, Uniben Yao Ayikoe
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    On input parameters, methods and assumptions for energy balance and retrofit analyses for residential buildings2017In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 137, p. 76-89Article in journal (Refereed)
    Abstract [en]

    In this study we explore key parameter values, methods and assumptions used for energy balance modelling of residential buildings in the Swedish context and analyse their effects on calculated energy balance of a typical multi-storey building from 1970s and on energy savings of energy efficiency retrofit measures. The parameters studied are related to microclimate, building envelope, occupancy behaviour, ventilation, and heat gains from electric appliances and persons. Our study shows that assumed indoor air temperature, internal heat gains and efficiency of ventilation heat recovery units have significant effect on the simulated energy performance of the studied building and energy efficiency measures. Of the considered microclimate parameter values and assumptions, the outdoor temperature, ground solar reflection and window shading have significant impact on the simulated space heating and cooling demands. On the contrary, the simulated energy performances are less affected by the variations in air pressure outside and the percentage of wind load that hits the building. We found that input data and assumptions used for energy balance calculations and energy saving analyses vary significantly in the Swedish context. These result in significantly different calculated final energy performance of buildings and energy efficiency measures. To inform accurate analysis of energy performance of building and energy saving measures, input parameters used in simulation models need to be appropriate.

  • 58.
    Druenert, F.
    et al.
    Univ Jena, Germany.
    Blanz, M.
    Univ Jena, Germany;Univ Highlands & Isl, UK.
    Pollok, K.
    Univ Jena, Germany.
    Pan, Z.
    Univ Jena, Germany.
    Wondraczek, L.
    Univ Jena, Germany.
    Möncke, Doris
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Natl Hellen Res Fdn, Greece.
    Copper-based opaque red glasses - Understanding the colouring mechanism of copper nanoparticles in archaeological glass samples2018In: Optical materials (Amsterdam), ISSN 0925-3467, E-ISSN 1873-1252, Vol. 76, p. 375-381Article in journal (Refereed)
    Abstract [en]

    Red opaque glasses of two different sites in central Germany, a medieval glassworks in Glashutten, Taunus Mountains, and an early modern glassworks in Wieda, Harz Mountains, were analysed with regard to their optical appearance. By scanning electron microscopy and X-ray diffraction, metallic copper nanoparticles were identified as a conspicuous constituent in these glasses. In addition, similar opaque red glasses were reproduced in the laboratory in order to better understand the manufacturing process. Detailed analysis of the optical scattering was conducted in order to evaluate the role of Cu-0 nanoparticles in the colouring mechanism relative to other possible reasons of colouration. We find clear differences between the possible contributions of Cu2O (cuprite) particles and metallic copper (Cu-0) nanoparticles. Through simulated backscattering spectra we were able to calculate an average copper particle radius in the archaeological glass samples resulting in a value of up to 95 nm, which matches well the results of SEM investigation (minimum 65 nm). Using the methods we applied in this study, it becomes possible to reconstruct various processing conditions as they were applied in medieval manufacture of these particular materials. (C) 2018 Elsevier B.V. All rights reserved.

  • 59.
    Druenert, Ferdinand
    et al.
    Univ Jena, Germany.
    Palamara, Eleni
    Univ Peloponnese, Greece.
    Zacharias, Nikolaos
    Univ Peloponnese, Greece.
    Wondraczek, Lothar
    Univ Jena, Germany.
    Möncke, Doris
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Natl Hellen Res Fdn, Greece.
    Ancient Roman nano-technology: Insight into the manufacture of mosaic tesserae opacified by calcium antimonate2018In: Journal of the European Ceramic Society, ISSN 0955-2219, E-ISSN 1873-619X, Vol. 38, no 14, p. 4799-4805Article in journal (Refereed)
    Abstract [en]

    Opaque mosaic glass tesserae containing calcium antimonates from Ancient Messene, Greece (1st-4th century CE) were investigated by scanning electron microscopy, Raman spectroscopy and X-ray diffraction. Both trigonal CaSb2O6 and cubic Ca2Sb2O2, with crystallite diameters below 1 pm, were identified as opacifying agents. To better understand ancient technologies, we prepared model glasses that were opacified by crystallisation via a secondary heat treatment, by direct crystallisation during the melting process, or by the addition of pre-reacted calcium antimonate to a base glass. We found that direct crystallisation replicated the antique glass artefacts most accurately. We demonstrated that 0.2 wt% of nucleating agents like TiO2 and SnO2 already exert significant influence on the crystallisation behaviour of calcium antimonates. Secondary scattering centres such as silica and carbonates contribute to the optical appearance. Concurrently, we reproduced opaque white glass ceramics in a reconstructed, wood-fired, Roman-type glass furnace built by Wiesenberg (2014).

  • 60.
    Efthimiopoulos, I.
    et al.
    Natl Hellen Res Fdn, Greece;Deutsch GeoForschungsZentrum GFZ, Germany.
    Palles, D.
    Natl Hellen Res Fdn, Greece.
    Richter, S.
    Friedrich Schiller Univ Jena, Germany;TRUMPF Lasertech GmbH, Germany.
    Hoppe, U.
    Univ Rostock, Germany.
    Möncke, Doris
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Natl Hellen Res Fdn, Greece.
    Wondraczek, L.
    Friedrich Schiller Univ Jena, Germany;Fraunhofer Inst Appl Opt & Precis Engn, Germany.
    Nolte, S.
    Friedrich Schiller Univ Jena, Germany;Fraunhofer Inst Appl Opt & Precis Engn, Germany.
    Kamitsos, E. I.
    Natl Hellen Res Fdn, Greece.
    Femtosecond laser-induced transformations in ultra-low expansion glass: Microstructure and local density variations by vibrational spectroscopy2018In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 123, no 23, article id 233105Article in journal (Refereed)
    Abstract [en]

    We report X-ray diffraction, resonance Raman, and infrared (IR) results on pristine ultra-low expansion (ULE) glass, a binary titanosilicate glass with 5.67 mol. % TiO2. ULE processing by femtosecond (fs) laser radiation leads to nanograting writing and photo-darkening for imaging and data storage. We investigate here the vibrational/structural changes induced by fs laser irradiation of ULE at 515 nm. Optical imaging revealed the formation of micro-cavities, and Raman mapping showed molecular oxygen trapped in such cavities of laser-irradiated ULE glass. While titanium in the pristine glass was found predominantly in tetrahedral Ti4+ sites highly dispersed in the silicate matrix, Raman and IR reflectance spectroscopy on laser-irradiated ULE indicated the formation of Ti3+ sites; Ti3+ octahedral sites are formed in the shells of cavities and aggregate in amorphous Ti2O3-type clusters, while the glass around and below cavities contains Ti3+ tetrahedral sites dispersed in the silicate network. Laser-processed ULE glass was found to also exhibit local restructuring of the silicate matrix. Shifts of the strong IR band at about 1080-1100 cm(-1) were translated into changes of the average Si-O-Si bond angle in the laser-transformed areas and found to reflect local density variations; the average local density increases relative to silica glass up to about 8% in the shells of micro-cavities and decreases by about 0.5% in the surrounding material. Chemical processes were proposed to account for photo-darkening and the local structural transformation effect in the probed areas of the fs laser-processed ULE glasses. Published by AIP Publishing.

  • 61.
    Egilsson, Snorri Jökull
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Cornelia, Magnås
    Uppströmsarbete i Bergaindustriområde, Kalmar: Spårning av utsläppskällor av koppar, zink, silver ochkadmium via avloppsanalys i ett industriområde2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Avloppsreningsverket Kalmar vatten AB arbetar med att minska halter av kadmium, silver, koppar och zink som kommer in till verket. Berga industriområde i Kalmar uppskattas som en möjlig källa för metallutsläpp. I det här projektet undersöks avloppsvattnet i delar av Berga för att se om det finns utsläpp av förhöjda metallkoncentrationer. Provtagning utfördes i utvalda avloppsbrunnar under två veckor. Proverna analyserade både internt inom Linnéuniversitetet med ICP-OES samt externt hos Eurofins med ICP-MS.  Undersökningen visade att tre av fyra provpunkter hade förhöjda koncentrationer av minst en metall. Detta kräver vidare arbete av reningsverket för att identifiera enstaka företag som släpper ut förhöjda halter av metallerna.

  • 62.
    Farinacci, Julie
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Biogas upgrading by Scenedesmus grown in diluted digestate2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of the work was to examine microalgae growth and nutrient elimination in various diluted digestates in the first trial, then to study CO2 removal from a simulated biogas mixture by the same strain in the second trial. Scenedesmus SCCP K-1826 was cultivated in the digestate from Sundet biogas plant diluted 10, 20 and 30 times. The cultures were open-air with occasional CO2 injections to control pH. On day 15, the best growth was obtained in the 10 times diluted sample. COD, TN and TP removal efficiencies were similar in each bottle as the strain didn’t perform better in any specific dilution. The control proved that additional mechanisms other than photosynthesis contributed to digestate cleaning. Using the 10 times diluted sludge, Scenedesmus was grown in sealed flasks filled with simulated biogas (35.3 % CO2 + 32.3 % CH4 + 32.3 % N2). More algal biomass was produced in this batch culture. Nutrient removal efficiencies were close to the ones reached in the open-air flasks. After 10 days, 96 % of carbon dioxide was reduced. Methane content was depleted as well, possibly due to undesirable methane oxidizing bacteria which infiltrated the medium.

  • 63.
    Finnerman, Oskar
    et al.
    Chalmers University of Technology.
    Razmjoo, Narges
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Guo, Ning
    Chalmers University of Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ström, Henrik
    Chalmers University of Technology.
    Reactor modelling assessment for urea-SNCR applications2017In: International journal of numerical methods for heat & fluid flow, ISSN 0961-5539, E-ISSN 1758-6585, Vol. 27, no 7, p. 1395-1411Article in journal (Refereed)
    Abstract [en]

    Purpose

    This work aims to investigate the effects of neglecting, modelling or partly resolving turbulent fluctuations of velocity, temperature and concentrations on the predicted turbulence-chemistry interaction in urea-selective non-catalytic reduction (SNCR) systems.

    Design/methodology/approach

    Numerical predictions of the NO conversion efficiency in an industrial urea-SNCR system are compared to experimental data. Reactor models of varying complexity are assessed, ranging from one-dimensional ideal reactor models to state-of-the-art computational fluid dynamics simulations based on the detached-eddy simulation (DES) approach. The models use the same reaction mechanism but differ in the degree to which they resolve the turbulent fluctuations of the gas phase. A methodology for handling of unknown experimental data with regard to providing adequate boundary conditions is also proposed.

    Findings

    One-dimensional reactor models may be useful for a first quick assessment of urea-SNCR system performance. It is critical to account for heat losses, if present, due to the significant sensitivity of the overall process to temperature. The most comprehensive DES setup evaluated is associated with approximately two orders of magnitude higher computational cost than the conventional Reynolds-averaged Navier–Stokes-based simulations. For studies that require a large number of simulations (e.g. optimizations or handling of incomplete experimental data), the less costly approaches may be favored with a tolerable loss of accuracy.

    Originality/value

    Novel numerical and experimental results are presented to elucidate the role of turbulent fluctuations on the performance of a complex, turbulent, reacting multiphase flow.

  • 64.
    Forss, Jörgen
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Continuous system based on rice husks for biodegradation of a simulated textile waste water containing azo dyes2013In: Continuous system based on rice husks for biodegradation of a simulated textile waste water containing azo dyes, International Water Association, Elsevier, 2013Conference paper (Other academic)
  • 65.
    Forss, Jörgen
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lindh, Markus V.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Microbial biotreatment of actual textile wastewater in a continuous sequential rice husk biofilter and the microbial community involved2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 1, article id e0170562Article in journal (Refereed)
    Abstract [en]

    Textile dying processes often pollute wastewater with recalcitrant azo and anthraquinone dyes. Yet, there is little development of effective and affordable degradation systems for textile wastewater applicable in countries where water technologies remain poor. We determined biodegradation of actual textile wastewater in biofilters containing rice husks by spectrophotometry and liquid chromatography mass spectrometry. The indigenous microflora from the rice husks consistently performed >90% decolorization at a hydraulic retention time of 67 h. Analysis of microbial community composition of bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS) gene fragments in the biofilters revealed a bacterial consortium known to carry azoreductase genes, such as Dysgonomonas, and Pseudomonas and the presence of fungal phylotypes such as Gibberella and Fusarium. Our findings emphasize that rice husk biofilters support a microbial community of both bacteria and fungi with key features for biodegradation of actual textile wastewater. These results suggest that microbial processes can substantially contribute to efficient and reliable degradation of actual textile wastewater. Thus, development of biodegradation systems holds promise for application of affordable wastewater treatment in polluted environments.

  • 66.
    Fredriksson, Anna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Mätvärdesbaserad metod för minskade emissioner i mindre förbränningsanläggningar2015Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    En mätvärdesbaserad metod har använts för att i den enskilda förbränningsanläggningen kunna visa vilka driftsätt som ger onormalt höga utsläpp. Tre olika typer av anläggningsdata har använts. Metoden fokuserar på gasfasreaktioner för att hållas oberoende av eldningsteknik. För att hålla nere beräkningstider och datorkapacitet fokuserar arbetet på summareaktioner och enkla samband vad gäller kemiska processer och förhållanden i eldstaden. 

  • 67.
    Fu, Jiapeng
    et al.
    Shandong University, China.
    Zhou, Binxuan
    Shandong University, China.
    Zhang, Zhen
    North China University of Water Resources and Electric Power, China.
    Wang, Tao
    Shandong University, China.
    Cheng, Xingxing
    Shandong University, China.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ma, Chunyuan
    Shandong University, China.
    One-step rapid pyrolysis activation method to prepare nanostructured activated coke powder2020In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 262, article id 116514Article in journal (Refereed)
    Abstract [en]

    A one-step rapid pyrolysis activation method is proposed to produce activated coke powder (ACP) via a drop tube reactor by using pulverized Datong coal (DTC) and pine wood (PW) as feedstock. Small feedstock particle size, high heating rate, and effective activation agent, i.e., the mixture of oxygen and steam were arranged for the fast formation and development of various pore structure of ACPs. Detail characteristics of the ACP were investigated by using the nitrogen adsorption measurement, scanning electron microscope (SEM) and Fourier transform infrared spectrometer (FTIR) analysis. Results showed that the ACP presented well-developed nanostructure with considerable pore volume, specific surface area and surface functional groups. The pore volume and specific surface area of PWC-O6S10 could reach 0.2373 cm3/g and 250.57 m2/g. Activation atmosphere had played an important role to develop the pore structure and morphology of the ACP. Under 6 vol% oxygen concentration, the optimum steam partial pressure for micropore development of DTC was about 15 vol%, while it mostly promoted the growth of mesopores for PWC. All ACP samples presented variety of C/O/N containing surface functional groups, including OH, CH, CC, CO, CO, COC, CN, CN, etc., which remained relatively stable as the activation agents concentration changed.

  • 68.
    Gavrilovic, Ljubisa
    et al.
    Norwegian University of Science and technology (NTNU), Trondheim, Norway.
    Blekkan, Ed Anders
    Norwegian University of Science and technology (NTNU), Trondheim, Norway.
    Venvik, H.J.
    Norwegian University of Science and technology (NTNU), Trondheim, Norway.
    Holmen, Anders
    Norwegian University of Science and technology (NTNU), Trondheim, Norway.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Influence of potassium species on Co based Fischer-Tropsch-catalyst.2016Conference paper (Refereed)
    Abstract [en]

    1. Introduction

    The purpose of this work is better understanding of the alkali influence on Co-based F-T catalyst. Since potassium is one of the elements that can be present in syngas from biomass[1], one of the questions is how potassium species affect the Co catalyst. From previous work it has been shown that alkali species act as poisons, thus deactivating catalysts[2]. Most previous work in this group[3][4] and by others[5] has concerned Co catalysts that were exposed to potassium species by incipient wetness impregnation, which is essentially different from the real behaviour during the gasification process where the species will mainly be in the vapor phase. In the present work we study potassium influence on a Co-based catalyst, using aerosol technology as a new method for potassium deposition on the Co surface.

     

    2. Experimental

    4 different potassium salts were deposited using aerosol deposition on 20%Co/0.5%Re/γAl2O3. The amount of potassium salts deposited were determined using ICP analysis. Potassium salts were chosen from studies of the gases from biomass gasification[6]. These are K2SO4, KCl, KNO3 and K2CO3. KNO3 will be reduced to KOH during biomass gasification, but since in these experiments temperature was not so high and there was no H2/CO, most likely KNO3 will be deposited as such on the Co surface.

    BET N2 adsorption, H2 chemisorption, temperature programmed reduction (TPR) were used to characterize all the poisoned catalysts.

    Fischer Tropsch activity and selectivity measurements were performed at the in house build set-up, at 210°C, 20 bar and at H2:CO ratio of 2.1. The GHSV was consistently varied to maintain comparable CO conversion levels between 20-50%. A detailed description of the setup and procedures can be found elsewhere[3].

     

    3. Results

    The potassium species were deposited using aerosol technology in the apparatus shown in Fig. 1. Potassium salts are dissolved in deionized water and the solution is placed inside the atomizer, which produces aerosol particles. Nitrogen is used as a carrier gas which forces aerosol particles in the reactor direction. Before entering the reactor, the gas mixture carrying the aerosol is passing the impaction vessel to remove large particles. The catalyst bed is placed in the middle of the reactor, which can be heated up to 800°C. The generated aerosol particles were physically characterized according to their electrical mobility using a scanning mobility particle sizer (SMPS) consisting of a differential mobility analyser (DMA) and a condensation particle counter (CPC)[7]. The three target concentrations of potassium salts,  200 ppm, 800 ppm and 4000 ppm,  were monitored by the above-mentioned instruments.

    Results from characterization by elemental analysis, H2 chemisorption, BET surface area, TPR together with the results from the Fischer Tropsch synthesis i.e. CO conversion, selectivity, and activity will be compared with the same catalyst without any poison and also with previous results obtained from solution impregnation of the same poisons[8][3][9].

    4. Discussion

    The purpose of the work is to study how this procedure of poisoning Co catalyst with aerosol particles will affect catalyst performances during Fischer Tropsch reaction. Previous similar work on Ni catalyst in the SCR reaction using aerosol technology as a method of deposition, has proven loss in metallic surface area, decreasing of metal dispersion and severe reduction in the catalytic activity [7]. The idea is to develop a technique to transfer potassium species, and potentially other relevant impurities, in vapor phase to the catalyst surface. This new approach can to a great extent simulate behaviour during the real industrial process. The aerosol could better represent in situ poisoning and therefore give a more realistic picture of the effect of potassium. This knowledge will be useful for designing new BTL processes.

     

    5. Conclusion

    Aerosol technology was used as a new method for depositing potassium salts on the Co surface. Poisoned catalysts were tested in Fischer Tropsch synthesis reactor together with elemental analysis. Results are compared to the reference catalyst and with previous work which use IWI as poisoning method.

     

     

    6. References

    [1]       A. Norheim, D. Lindberg, J. E. Hustad, and R. Backman, Energy and Fuels, (2009)

    [2]       E. S. Wangen, A. Osatiashtiani, and E. A. Blekkan, Top. Catal., (2011)

    [3]       C. M. Balonek, A. H. Lillebø, S. Rane, E. Rytter, L. D. Schmidt, and A. Holmen, Catal. Letters, (2010)

    [4]       E. A. Blekkan, A. Holmen, S. Vada, Acta Chem. Scand., (1993)

    [5]       J. Gaube and H. F. Klein, Appl. Catal. A Gen., (126–132, 2008)

    [6]       H. M. Westberg, M. Byström, and B. Leckner, Energy and Fuels, (18–28, 2003)

    [7]       S. Albertazzi, F. Basile, J. Brandin, J. Einvall, G. Fornasari, C. Hulteberg, M. Sanati, F. Trifirò, and A. Vaccari, Biomass and Bioenergy, (2008)

    [8]       A. H. Lillebø, E. Patanou, J. Yang, E. A. Blekkan, and A. Holmen, in Catalysis Today, (2013)

    [9]       E. Patanou, A. H. Lillebø, J. Yang, D. Chen, A. Holmen, and E. A. Blekkan, Ind. Eng. Chem. Res., (2014)

    [10]     J. Einvall, S. Albertazzi, C. Hulteberg, A. Malik, F. Basile, A. C. Larsson, J. Brandin, and M. Sanati, Energy and Fuels, (2007)

  • 69.
    Gavrilovic, Ljubisa
    et al.
    Norwegian University of Science and Technology, Norway.
    Blekkan, Edd
    Norwegian University of Science and Technology, Norway.
    Holmen, Anders
    Norwegian University of Science and Technology, Norway.
    Venvik, Hilde
    Norwegian University of Science and Technology, Norway.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Fischer-Tropsch Synthesis: Investigation of CO catalyst by exposure to aerosol particles of potassium salts2015In: Norwegian Catalyst Symposium 2015, 2015Conference paper (Refereed)
  • 70.
    Gavrilovic, Ljubisa
    et al.
    Norwegian University of Science and Technology, Norway.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Holmen, Anders
    Norwegian University of Science and Technology, Norway.
    Venvik, Hilde
    Norwegian University of Science and Technology, Norway.
    Myrstad, R.
    SINTEF Materials and Chemistry, Norway.
    Blekkan, Edd
    Norwegian University of Science and Technology, Norway.
    Deactivation of Co-based Fischer-Tropsch catalyst by aerosol deposition of potassium salts2018In: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045, Vol. 57, no 6, p. 1935-1942Article in journal (Refereed)
    Abstract [en]

    A 20%Co/0.5%Re/γAl2O3 Fischer-Tropsch catalyst was poisoned by four potassium salts (KNO3, K2SO4, KCl, K2CO3) using the aerosol deposition technique, depositing up to 3500 ppm K as solid particles. Standard characterization techniques (H2 Chemisorption, BET, TPR) showed no difference between treated samples and their unpoisoned counterpart. The Fischer-Tropsch activity was investigated at industrially relevant conditions (210 °C, H2:CO = 2:1, 20 bar). The catalytic activity was significantly reduced for samples exposed to potassium, and the loss of activity was more severe with higher potassium loadings, regardless of the potassium salt used. A possible dual deactivation effect by potassium and the counter-ion (chloride, sulfate) is observed with the samples poisoned by KCl and K2SO4. The selectivity towards heavier hydrocarbons (C5+) was slightly increased with increasing potassium loading, while the CH4 selectivity was reduced for all the treated samples. The results support the idea that potassium is mobile under FT conditions. The loss of activity was described by simple deactivation models which imply a strong non-selective poisoning by the potassium species.

  • 71.
    Gavrilovic, Ljubisa
    et al.
    Norwegian University of Science and Technology, Norway.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Holmen, Anders
    Norwegian University of Science and technology, Norway .
    Venvik, Hilde
    Norwegan University of Science and technology, Norway.
    Myrstad, Rune
    SINTEF Industry, Norway.
    Blekkan, Edd
    Norwegan University of Science and Technology, Norway.
    Fischer-Tropsch synthesis: Investigation of the deactivation of a Co catalyst by exposure to aerosol particles of potassium salt2018In: Applied Catalysis B: Environmental, ISSN 0926-3373, E-ISSN 1873-3883, Vol. 230, p. 203-209Article in journal (Refereed)
    Abstract [en]

    The influence of potassium species on a Co based Fischer-Tropsch catalyst was investigated using an aerosol deposition technique. This way of poisoning the catalyst was chosen to simulate the actual potassium behaviour during the biomass to liquid (BTL) process utilizing gasification followed by fuel synthesis. A reference catalyst was poisoned with three levels of potassium and the samples were characterized and tested for the Fischer-Tropsch reaction under industrially relevant conditions. None of the conventional characterization techniques applied (H2 Chemisorption, BET, TPR) divulged any difference between poisoned and unpoisoned samples, whereas the activity measurements showed a dramatic drop in activity following potassium deposition. The results are compared to previous results where incipient wetness impregnation was used as the method of potassium deposition. The effect of potassium is quite similar in the two cases, indicating that irrespective of how potassium is introduced it will end up in the same form and on the same location on the active surface. This indicates that potassium is mobile under FTS conditions, and that potassium species are able to migrate to sites of particular relevance for the FT reaction.

  • 72.
    Gavrilovic, Lubisa
    et al.
    Norwegian University of Science and Technology, Norway.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Holmen, Anders
    Norwegian University of Science and Technology, Norway.
    Venvik, Hild J.
    Norwegian University of Science and Technology, Norway.
    Myrstad, Rune
    SINTEF Industry, Norway.
    Blekkan, Edd A.
    Norwegian University of Science and Technology, Norway.
    The effect of aerosol-deposited ash components on a cobalt-based Fischer–Tropsch catalyst2019In: Reaction Kinetics, Mechanisms and Catalysis, ISSN 1878-5190, E-ISSN 1878-5204, Vol. 127, no 1, p. 231-240Article in journal (Refereed)
    Abstract [en]

    The effect of ash salts on Co-based Fisher–Tropsch catalysts was studied using an aerosol deposition technique. The major elements in the ash were found to be K, S and Cl. The ash was deposited on a calcined catalyst as dry particles with an average diameter of approx. 350 nm. The loading of ash particles was varied by varying the time of exposure to the particles in a gas stream. Catalyst characterization did not reveal significant differences in cobalt dispersion, reducibility, surface area, pore size, or pore volume between the reference and the catalysts with ash particles deposited. Activity measurements showed that following a short exposure to the mixed ash salts (30 min), there were no significant loss of activity, but a minor change in selectivity of the catalyst . Extended exposure (60 min) led to some activity loss and changes in selectivity. However, extending the exposure time and thus the amount deposited as evidenced by elemental analysis did not lead to a further drop in activity. This behavior is different from that observed with pure potassium salts, and is suggested to be related to the larger size of the aerosol particles deposited. The large aerosol particles used here were probably not penetrating the catalyst bed, and to some extent formed an external layer on the catalyst bed. The ash salts are therefore not able to penetrate to the pore structure and reach the Co active centers, but are mixed with the catalyst and detected in the elemental analysis.

  • 73.
    Gilchrist, Oliver
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Larsson, Emil
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Energisimulering Av Äldre Flerbostadshus: En simulering av förbättringspotential i äldrefastigheter med hjälp av solceller, värmepumpar och tilläggsisolering.2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I detta examenarbete har olika energieffektiviseringsåtgärder jämförts på två flerbostadshus i Ljungby kommun vars namn är Halfdan och Arngrim. I det första alternativet modulerades de befintliga byggnaderna för att kunna se dess totala energianvändning. Det andra alternativet består av att tilläggsisolera vindsvåningen samt byte av fönster och dörrar. Dessa åtgärder bidrar med en besparing på ca. 90 000 kWh/år Halfdan samt 55 000 kWh/år Arngrim. I det tredje alternativet installeras en frånluftsvärmepump samt en solcellsanläggning i vardera byggnad. Detta resulterar i en energibesparing på ca. 127 000 kWh/år i Halfdan samt 101 000 kWh/år i Arngrim.

     

    Fastigheterna har simulerats i Energiberäkningar och VIP+ Energy, där resultatet påvisar att frånluftsvärmepumpen bidrar med den största energibesparingen i förhållande till det andra alternativet.  

  • 74.
    Grund Bäck, Lina
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Electronic spectra and molar extinction coefficient of Cu2+ in mixed alkali-alkaline earth-silica glasses2015In: Physics and Chemistry of Glasses-European Journal of Glass Science and Technology Part B, ISSN 1753-3562, Vol. 56, no 1, p. 8-14Article in journal (Refereed)
    Abstract [en]

    CuO is a very common colorant in blue to turquoise-blue glasses. It is well known that the absorption peak at about 800 nm for silicate glasses is caused by Cu2+, octahedrally coordinated by 6 oxygen ions. It is also known that the [Cu+]/[Cu2+] ratio, the location of the absorption peak and the extinction coefficient of Cu2+ depends on the glass composition. Many investigations have been published with CuO as a colouring agent, but almost none with a mix of Na2O and K2O or CaO and BaO in the base glass. In this study, a base glass composition of 20R2O-10MO-70SiO2 (mol%, R=Na, K and M=Ca, Ba) is used and 0.40 mol% CuO is added. The molar extinction coefficient of Cu2+ is determined for the glasses and peak positions and heights are also presented and discussed.

  • 75.
    Grund Bäck, Lina
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Redox reactions and structure - properties relations in mixed alkali/alkaline earth glasses: - The role of antimony oxides during the fining process- A structural study of copper(I) and copper(II)2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    It is important to optimize glass compositions for their specific purpose but also for the efficiency of the production process, the manufacturing of glass. This will be beneficial economically and environmentally. Today many processes and glass compositions are already optimized, but due to more strict legislation on toxic elements and substances there must be changes in many glass compositions. One of these elements is antimony; the oxide is used as fining agent to obtain a bubble free glass within a reasonable process time. One aim with this thesis is to obtain a deeper understanding of the fining mechanism in 20R2O-10MO-70SiO2 (R=Na and/or K, M = Ca and/or Ba, Mg, Sr) glasses in order to minimise the amount of Sb2O3. Another intention is to study the structure of 20R2O-10CaO-70SiO2 (R = Na, K) with Cu2+ as probe ion and thus get a deeper knowledge of the surrounding glass matrix.  The optical basicity scale is used to determine the acid/base character of the different glass compositions.

     

    Fining efficiency results showed a remarkable increase of the number of remaining bubbles when the glass contains either approximately equal amounts of Na and K or Ca and Ba, Mg or Sr. The much higher number of bubbles in the potassium containing glasses compared to the sodium containing is explained by the increase in viscosity, the increase in optical basicity and thus lower oxygen activity. The differences in the fining efficiency when altering alkaline earth ions cannot be explained by the optical basicity values, it seems to be a more complicated situation.

     

    This thesis also reports maximum in Vickers hardness and packing density as well as minimum in glass transition temperature for the mixed alkali glasses. The mixed alkaline earth glasses do not exhibit any clear nonlinear behaviour. Raman spectroscopy measurements showed a variation in the network connectivity which has a clear relation to the optical basicity of the different glass compositions. The combination of UV-Vis-NIR and X-ray absorption spectroscopy measurements showed that the coordination sphere for Cu(II) is a tetragonal distorted octahedron with two elongated Cu-O bonds along the z axis. There were no trends in the degree of tetragonal distortion, thus it was about the same for all the investigated glass compositions. Cu(I) is found to be coordinated by two oxygen ligands in mainly linear coordination sphere, evidenced from X-ray absorption spectroscopy.

  • 76.
    Grund Bäck, Lina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Karlsson, Stefan
    Glafo, the Glass Research Institute.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Physical properties and Raman Spectroscopy of mixed alkali/alkaline earth silicate glassesManuscript (preprint) (Other academic)
  • 77.
    Grund Bäck, Lina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. RISE, Sweden.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Karlsson, Stefan
    RISE, Sweden.
    Möncke, Doris
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. National Hellenic Research Foundation, Greece.
    Kamitsos, Efstratios
    National Hellenic Research Foundation, Greece.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Mixed alkali/alkaline earth‐silicate glasses: Physical properties and structure by vibrational spectroscopy2019In: International Journal of Applied Glass Science, ISSN 2041-1286, Vol. 10, no 3, p. 349-362Article in journal (Refereed)
    Abstract [en]

    In this article, we investigate the correlation of selected physical properties with structural changes in quaternary mixed modifier alkali/alkaline earth oxide silicate glass systems, focusing either on the mixed alkali effect [(20−x)Na2O–xK2O–10CaO–70SiO2 (x = 0, 5, 10, 15, 20)] or on the mixed alkaline earth effect [20Na2O–(10−y)CaO–yBaO–70SiO2 (y = 0, 5, 10)]. A maximum microhardness and packing density, as well as a minimum glass transition temperature were observed for mixed alkali glasses. The mixed alkaline earth glasses do not exhibit any clear extrema in any of the properties studied. The hardness and glass transition temperature decreases, while the density and molar volume increases with increasing BaO content. Raman spectroscopy showed an increase in the Q3 group compared to the Q2 and Q4 groups as the high field strength ions Na+ or Ca2+ are substituted by their low field strength analogs K+ or Ba2+. In the mixed alkali series, the high field strength ion Na+, seems to push the low field strength ion K+ into lower energy sites when present simultaneously, while such an effect is not apparent for the mixed alkaline earth glasses, where the far IR spectra of mixed glasses are equivalent to the weighted averages of the pure glasses.

  • 78.
    Grund Bäck, Lina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. RISE Research Institutes of Sweden, Sweden.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Karlsson, Stefan
    RISE Research Institutes of Sweden, Sweden;Friedrich Schiller University of Jena, Germany.
    Wondraczek, Lothar
    Friedrich Schiller University of Jena, Germany.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    X-ray and UV-Vis-NIR absorption spectroscopy studies of the Cu(I) and Cu(II) coordination environments in mixed alkali-lime-silicate glasses2019In: Journal of Non-Crystalline Solids: X, ISSN 2590-1591, article id 100029Article in journal (Refereed)
    Abstract [en]

    The local structures of Cu(I) and Cu(II) in (20-x)Na2O-xK2O-10CaO-70SiO2 glasses with a copper content of 0.4 mol% have been investigated by Cu K-edge extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES). Complementary data for Cu(II) was derived using UV–Vis-NIR spectroscopy. Indication for mainly linear two-fold coordination of the Cu+ ion was found by both EXAFS and XANES, but other coordination between Cu+ and O2– cannot be excluded. The Cu(I)O bond lengths were found to be 1.79–1.83 ± 0.02 Å. EXAFS results showed that Cu(II) was mostly present in a Jahn-Teller distorted environment with oxygen, an octahedron with four shorter Cu(II)O bonds and two longer in axial position. The equatorial bond lengths were found to be 1.89–1.91 ± 0.02 Å and the axial 2.20–2.24 ± 0.02 Å with no effect of the Jahn-Teller distortion of the octahedron when the glass composition was altered.

  • 79.
    Grund Bäck, Lina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. RISE Glas.
    Lagerbielke, Erika
    Linnaeus University, Faculty of Arts and Humanities, Department of Design.
    Eternal glass: Rapport - studie om återvinning av glas2018Report (Other academic)
  • 80.
    Grund, Lina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Optical and Physical Properties of CuO-doped mixed alkali: alkaline earth silica glasses2014Conference paper (Refereed)
  • 81.
    Gustafsson, Jakob
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Olofsson, Simon
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Energieffektivisering i kulturhistoriska byggnader: En studie av Vederslövs kyrka2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Kyrkor som är byggda innan år 1940 skyddas i enlighet med 4 kap. Kyrkliga kulturminnen ur Kulturmiljölagen. Samtidigt efterfrågar kyrkobesökare större krav på inomhusklimatet som för kyrkornas inventarier leder till skador. De två parametrarna temperatur samt relativ fukthalt, och förhållandet mellan dem, utgör därför en viktig del för både bevarandet av kulturhistoriska byggnader och dess inventarier. Vederslövs kyrka är byggd i sten och anses vara en av Kronobergs läns mest välbevarade kyrkor från slutet av 1800-talet. Efter inhämtning av mätvärden från JEFF Electronics styrsystem och utplacerade loggrar i kyrkan har simulering i IDA ICE utförts. Därefter har fyra stycken energieffektiviseringsåtgärder för Vederslövs kyrka presenterats.

  • 82.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Dodoo, Ambrose
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Effects of different techno-economic regimes on viability of deep energy renovation of an existing Swedish multi-family building2017In: ECEEE 2017 Summer Study: Consumption, Efficiency & Limits, European Council for an Energy Efficient Economy (ECEEE), 2017, p. 1064-1073Conference paper (Refereed)
    Abstract [en]

    This paper presents and demonstrates a method for analysis of cost-effectiveness of energy efficiency measures for buildings. Based on the method, cost-optimal energy efficiency measures are calculated considering total and marginal investment costs as well as net present value of energy savings for the measures under different technical and economic scenario. The method is applied to a 1970s Swedish multi-family building to explore the profitability of different energy renovation measures when implemented individually or in packages. The measures analysed include improved thermal insulation for exterior and basement walls as well as attic floor, improved new windows, efficient electrical appliances, efficient water taps, and exhaust air ventilation heat recovery systems. Our results show that the economic viability of the retrofit measures is sensitive to the techno-economic parameters used including, real discount rates, energy price increases and technical lifetime of retrofit measures. Still, about 34–51 % reduction of final heat demands is economically viable for the analysed building. Resource-efficient taps is the most cost-effective measure while improved thermal envelope insulation for exterior walls is the least cost-effective among the measures analysed for the studied building. This study shows the significance of different technical and economic parameters in achieving deep-energy savings from renovation of a building in a cold climate. 

  • 83.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Haus, Sylvia
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lundblad, Mattias
    Swedish University of Agricultural Sciences.
    Lundström, Anders
    Swedish University of Agricultural Sciences.
    Ortiz, Carina A.
    Swedish University of Agricultural Sciences.
    Sathre, Roger
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Wikberg, Per-Erik
    Swedish University of Agricultural Sciences.
    Climate change effects of forestry and substitution of carbon-intensive materials and fossil fuels2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 67, p. 612-624Article in journal (Refereed)
    Abstract [en]

    We estimate the climate effects of directing forest management in Sweden towards increased carbon storage in forests with more land set-aside for protection, or towards increased forest production for the substitution of carbon-intensive materials and fossil fuels, relative to a reference case of current forest management. We develop various scenarios of forest management and biomass use to estimate the carbon balances of the forest systems, including ecological and technological components, and their impacts on the climate in terms of radiative forcing. The scenario with increased set-aside area and the current level of forest residue harvest resulted in lower cumulative carbon emissions compared to the reference case for the first 90 years, but then showed higher emissions as reduced forest harvest led to higher carbon emissions from energy and material systems. For the reference case of current forest management, increased harvest of forest residues gave increased climate benefits. The most climatically beneficial alternative, expressed as reduced cumulative radiative forcing, in both the short and long terms is a strategy aimed at high forest production, high residue recovery rate, and high efficiency utilization of harvested biomass. Active forest management with high harvest levels and efficient forest product utilization will provide more climate benefit, compared to reducing harvest and storing more carbon in the forest.

  • 84.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Haus, Sylvia
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ortiz, Carina A.
    Swedish University of Agricultural Sciences.
    Sathre, Roger
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Climate effects of bioenergy from forest residues in comparison to fossil energy2015In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 138, p. 36-50Article in journal (Refereed)
    Abstract [en]

    Forest residues can be left at the harvest site to gradually decompose, or can be collected for energy purposes. This study analyzes the primary energy and climate impacts of bioenergy systems where forest residues are collected and used for electricity, heat and transportation, compared to fossil-based energy systems where fossil fuels provide the same services while forest residues are left on site to decompose. Time profiles are elaborated of primary energy use and carbon dioxide emissions from various energy applications fulfilled by bioenergy or fossil energy systems. Different biological decay functions are considered based on process-based modeling and inventory data across various climate zones. For all scenarios, the changes in cumulative radiative forcing (CRF) are calculated over a 300-year period, to evaluate the short- and long-term contributions of forest residue to climate change mitigation. A life cycle perspective along the full energy chains is used to evaluate the overall effectiveness of each system. The results show largest primary energy and climate benefits when forest residues are collected and used efficiently for energy services. Using biomass to substitute fossil coal provides greater climate change mitigation benefits than substituting oil or fossil gas. Some bioenergy substitutions result in positive CRF, i.e. increased global warming, during an initial period. This occurs for relatively inefficient bioenergy conversion pathways to substitute less carbon intensive fossil fuels, e.g. biomotor fuel used to replace diesel. More beneficial bioenergy substitutions, such as efficiently replacing coal, result immediately in reduced CRF. Biomass decay rates and transportation distance have less influence on climate benefits.

  • 85.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Haus, Sylvia
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ortiz, Carina
    Swedish University of Agricultural Sciences.
    Sathre, Roger
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Dynamic impacts of forest residues on primary energy use and greenhouse gas emissions2014In: The 9th Conference on Sustainable Development of Energy, Water and Environment Systems - SDEWES. September 20 - 27, 2014, Venice-Istanbul, 2014Conference paper (Refereed)
  • 86.
    Gustavsson, Leif
    et al.
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Joelsson, Jonas M.
    Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Mittuniversitetet, Institutionen för teknik och hållbar utveckling.
    Where are biomass fuels best used in the Swedish energy system?: efficient use of biomass fuels given different targets with respect to CO2 emission and oil use reduction2011Report (Other academic)
  • 87.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Sathre, Roger
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Dodoo, Ambrose
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Climate change effects over the lifecycle of a building - Report on methodological issues in determining the climate change effects over the life cycle of a building: Final report for Boverket2015Report (Other academic)
  • 88.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Bioenergy pathways for cars: Effects on primary energy use, climate change and energy system integration2016In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 115, no 3, p. 1779-1789Article in journal (Refereed)
    Abstract [en]

    Different pathways and technologies can be used to convert woody biomass to transport services, but the biomass use and climate implications vary strongly between the alternatives. This study focuses on primary energy use and climate change effects of using bioenergy for transportation in the context of a renewable-based energy system. Integrated pathways to improve the energy efficiency of power and transportation sectors and integrated intermittent renewable energy are considered. The results show that the bioenergy pathway that produces biomotor fuels to replace fossil fuels leads to high primary energy use and instantaneous biogenic CO2 emission per km of driving distance, thus increasing global warming during the first 40e50 years, compared to fossil alternatives. The electric vehicle pathway using bioelectricity from combined heat and power plants leads to immediate global cooling and much greater climate benefits in the long run compared to biomotor fuels. Climate change effects of light-duty vehicles could be strongly reduced by changes in technology together with system integration that links the transport sector to the electricity and heating sectors. The use of biomass should be considered in the context of the overall integrated energy system, and in relation to the development of energy conversion technologies between different sectors.

  • 89.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Effects of different bioenergy pathways on primary energy efficiency, climate mitigation and energy system integration2015In: The 10th Conference on Sustainable Development of Energy, Water and Environment Systems – SDEWES 2015. September 27- October 3, 2015, Dubrovnik, Croatia, 2015Conference paper (Refereed)
    Abstract [en]

    Woody biomass is an important renewable energy resource that can be used directly or indirectly in the electricity, heat and transport sectors. Different technologies and conversion pathways can be used to convert woody biomass to supply different types of energy services. The primary energy and climate implications of bioenergy systems depend on which conversion technologies and pathways are used to produce the energy services, as well as how the services would have been supplied without the bioenergy system. Here, we focus on bioenergy for transportation in the context of a total renewable-based energy system. We contrast two different pathways: (i) biomotor fuel production in stand-alone plants and (ii) bioelectricity production in standalone plants and district heating systems with CHP plants and heat storage capacity for electric and plug-in hybrid vehicles. We quantify the primary energy use and the instantaneous biogenic CO2 of the two alternatives, per km of driving distance. We consider both commercially available technologies and emerging technologies for biomass-based conversion systems. Furthermore, for the two alternatives we discuss potential benefits of integration between the electricity, heating and transport sectors, to enable a better use of infrastructure. The results show that primary energy use and instantaneous biogenic CO2 emission vary strongly between the alternatives. The primary energy efficiency is much higher and gives less instantaneous biogenic CO2 emission for electric and plug-in hybrid vehicles compared to vehicles using biomotor fuels. Furthermore, the potential integration benefits between the electricity, heating and transport sectors are much larger due to the integration potential of heat storage capacity in DHS and battery storage capacity in electric and plug-in hybrid vehicles, as well as an improved overall integration capacity between the sectors. This study suggests that use of biomass should be considered in the context of the overall energy system, and in relation to the development of energy conversion technologies and integration potential between different energy sectors, to find primary energy efficient alternatives giving climate benefits in both a short- and long-term perspective.

  • 90.
    Hagos, Dejene Assefa
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Gjovik Univ Coll.
    Gebremedhin, Alemayehu
    Gjovik Univ Coll.
    Zethraeus, Björn
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Towards a flexible energy system - A case study for Inland Norway2014In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 130, p. 41-50Article in journal (Refereed)
    Abstract [en]

    This paper analyze the benefits of the use of bioenergy, solar thermal and wind energy in a flexible energy system to increase the share of renewable sources (RES) in primary energy supply, reduce primary energy consumption (PEC) and ensure power supply security in Inland Norway, and Norway at large. Firstly, the Inland reference energy system was built and validated using the EnergyPLAN system analysis tool based on the year 2009. Two alternative systems (scenarios), mainly of bio-heat and heat pumps in individual and district heating systems were then constructed and compared with the reference system using EnergyPLAN. The quality of a given energy system can be best described by its PEC, RES, emission levels and socio-economic costs. The result shows that it is plausible to improve the quality of the Inland energy system by optimal resource assortment in the energy mix. Integrated use of bin-heat and heat pumps in individual and district heating systems, as a replacement for direct electric heaters would reduce PEC and socio-economic costs considerably more than intensive bio-heating deployment alone, thereby increasing total domestic green electricity generation. The ability to integrate wind power and its value in the Inland energy system is more reflected by reducing imports of electricity during peak demand periods in winter, as wind power availability in the region is significant as opposed to the low precipitation during these periods. In addition, increasing wind energy penetration helps to limit biomass consumption in a district heating system built on heat pumps and bio-heat boilers. (C) 2014 Elsevier Ltd. All rights reserved.

  • 91.
    Haus, Sylvia
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Climate impact of the sustainable use of forest biomass in energy and material system: a life cycle perspective2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Human society releases greenhouse gas emissions to the atmosphere while providing housing, heat, mobility and industrial production. Man-made greenhouse gas emissions are the main causes of climate change, coming mainly from burning fossil fuels and land-use changes. Sustainably managed forests play an important role in climate change mitigation with the prospect of sustainably providing essential materials and services as part of a low-carbon economy, both through the substitution of fossil-intensive fuels and material and through their potential to capture and store carbon in the long-term perspective.

    The overall aim of this thesis was to develop a methodology under a life cycle perspective to assess the climate impact of the sustainable use of forest biomass in bioenergy and material systems. To perform this kind of analysis a methodological framework is needed to accurately compare the different biological and technological systems with the aim to minimize the net carbon dioxide emissions to the atmosphere and hence the climate impact. In such a comparison, the complete energy supply chains from natural resources to energy end-use services has to be considered and are defined as the system boundaries.

    The results show that increasing biomass production through more intensive forest management or the usage of more productive tree species combined with substitution of non-wood products and fuels can significantly reduce global warming. The biggest single factor causing radiative forcing reduction was using timber to produce wood material to replace energy-intensive construction materials such as concrete and steel. Another very significant factor was replacing fossil fuels with forest residues from forest thinning, harvest, wood processing, and post-use wood products. The fossil fuel that was replaced by forest biomass affected the reductions in greenhouse gas emissions, with carbon-intensive coal being most beneficial to replace. Over the long term, an active and sustainable management of forests, including their use as a source for wood products and bioenergy allows the greatest potential for reducing greenhouse gas emissions.

  • 92.
    Haus, Sylvia
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Sathre, Roger
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Climate mitigation comparison of woody biomass systems with the inclusion of land-use in the reference fossil system2014In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 65, p. 136-144Article in journal (Refereed)
    Abstract [en]

    While issues of land-use have been considered in many direct analyses of biomass systems, little attention has heretofore been paid to land-use in reference fossil systems. Here we address this limitation by comparing forest biomass systems to reference fossil systems with explicit consideration of land-use in both systems. We estimate and compare the time profiles of greenhouse gas (GHG) emission and cumulative radiative forcing (CRF) of woody biomass systems and reference fossil systems. A life cycle perspective is used that includes all significant elements of both systems, including GHG emissions along the full material and energy chains. We consider the growth dynamics of forests under different management regimes, as well as energy and material substitution effects of harvested biomass. We determine the annual net emissions of CO2, N2O and CH4 for each system over a 240-year period, and then calculate time profiles of cRF as a proxy measurement of climate change impact. The results show greatest potential for climate change mitigation when intensive forest management is applied in the woody biomass system. This methodological framework provides a tool to help determine optimal strategies for managing forests so as to minimize climate change impacts. The inclusion of land-use in the reference system improves the accuracy of quantitative projections of climate benefits of biomass-based systems. (c) 2014 Elsevier Ltd. All rights reserved.

  • 93.
    Hemström, Kerstin
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Perceptions of intensive forestry and multi-storey wood frames among Swedish actors2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Implementation of intensive forestry (fertilization, cultivation of non-native tree species, and clone cultivation) on part of the forested land area in Sweden and an increased construction of wood-framed multi-storey buildings can contribute to reduce the net carbon dioxide emissions of the built environment. This thesis evaluates the acceptance of and interest in intensive forestry and multi-storey wood frames among different actors, and some of the underlying reasons for their approach. The results of quantitative and qualitative studies among members of the general public, private forest owners, architects, and contracts managers in Sweden are presented in six different papers. Both intensive forestry and multi-storey wood frames lack sufficient acceptance and compliance with relevant institutions such as priorities, norms, and regulations in the eyes of the studied actors. The acceptance of intensive forestry would be larger among members of the general public if they would perceive such practices to have less negative environmental effects and perceive a greater need to increase forest growth. Among the private forest owners, the interest to cultivate non-native tree species would be larger if there were more positive attitudes towards the economic consequences. Architects and contracts managers associate multistorey wood frames with several disadvantages and uncertainties, primarily with respect to fire safety, stability, durability, and sound proofing. The contracts managers’ perceptions have stronger implications for the prospects for wood frames, than the architects’ perceptions do. Promotional activities aimed to change such perceptions may improve the prospects for more wood framed multi-storey buildings in Sweden. The path dependency of Swedish multi-storey construction however implies that such activities are not enough for multi-storey wood frames to diffuse to greater extent. Broader changes to the wider context of the decisions taken in construction projects, e.g. to policy or economic environments, which change the priorities of the construction industry actors, are needed.

  • 94.
    Hemström, Kerstin
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Mahapatra, Krushna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Contractor Perceptions of Very Energy Efficient New Multi-Story Residential Buildings2014In: World Sustainable Building 2014 Barcelona Conference: Sustainable Buildings: Results ; Are We Moving as Quickly as We Should? It's Up to Us!, GBCe , 2014Conference paper (Refereed)
    Abstract [en]

    To facilitate design of policies and strategies which aim to promote a sustainable development of the built environment, a deeper understanding of factors influencing the decisions taken in construction projects is needed. This study investigates Swedish contractors’ perceptions of the new-build of very energy efficiency multi-storey residential buildings (e.g. passive houses). The results of interviews with twenty selected contracts managers disclose several perceived disadvantages and risks associated with such buildings which influence the interest to invest in high energy efficiency. These include several cost and market-related issues as well as issues relating to the performance of the buildings. Without market intervention it seems unlikely that very energy efficient multi-storey residential buildings will diffuse to any substantial degree within the Swedish construction industry.

  • 95.
    Hemström, Kerstin
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Mahapatra, Krushna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    The sociotechnical regime and Swedish contractor perceptions of structural frames2017In: Construction Management and Economics, ISSN 0144-6193, E-ISSN 1466-433X, Vol. 35, no 4, p. 184-195Article in journal (Refereed)
    Abstract [en]

    To deepen the understanding of the sociotechnical regime that directs the selection of structural frames in multifamily buildings in Sweden, we study the perceptions of contractor representatives. Contract managers (CMs) employed at contractor firms were interviewed regarding their role, the selection of the structural frame and how they perceived different options. The results show that CMs largely influence the selection of the structural frame in multifamily buildings, which are guided by the established concrete-based sociotechnical regime. The regime is maintained through cognitive rules regarding structural frame options and the alignment of skills of construction professionals. Because of their influence and their investments in the skills of construction workers, CMs make important contributions to maintain the regime and the concrete path dependency. Furthermore, the regime varies in strength in different locations. Some locations carry a strong norm to cast concrete frames on site. This makes it more difficult to deviate from the established practice. In other locations, wood-promoting initiatives have changed the cognitive rules associated with the regime. Nonetheless, the sociotechnical regime makes the selection of concrete structural frames beneficial. This prevents wood-framed multifamily buildings from entering common usage, even though such buildings can contribute to mitigating climate change.

  • 96.
    Hemström, Kerstin
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Mahapatra, Krushna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Architects’ perception of the innovativeness of the Swedish construction industry2017In: Construction Innovation, ISSN 1471-4175, E-ISSN 1477-0857, Vol. 17, no 2, p. 244-260Article in journal (Refereed)
    Abstract [en]

    Purpose – The aim of this paper is to enhance the understanding of architects’ perceptions of the propensityto adopt innovations in building construction.

    Design/methodology/approach – Based on a theoretical underpinning of the multilevel perspective on socio-technical transitions, a web-based questionnaire (n = 412) was used to empirically investigate Swedish architects’ perceptions of innovativeness in the building construction industry. Specifically, the study looks at perceptions of the level of innovativeness (propensity to adopt innovations), relevant barriers to the adoption of innovations, the influence of different actors and ways of facilitating innovativeness.

    Findings – Architects perceive a low level of innovativeness in the Swedish building construction industry because of a number of barriers of varying relevance. These barriers belong to interwoven regulative,normative and cognitive rules (i.e. institutions) that guide actor behaviour, which contribute to the path dependency of the industry. The site-specific nature of building construction, promotional activities from suppliers and the level of competition in the industry is perceived as being of little relevance. The findings suggest that a number of interventions are necessary to facilitate innovativeness of the Swedish construction industry. To change the lock-in mechanisms of the established cognitive and normative rules, regulative rulesneed to change as well. According to architects, contractors and construction clients are the most influentialand therefore have the most power to change the rules associated with path dependency.

    Research limitations/implications – The focus on a single construction professional in Sweden necessitates a discussion on these perceptions from the standpoint of other actors.

    Practical implications – Architects perceive a need for change in the construction industry and suggestthat changed regulative rules can help overcome path dependency and facilitate innovativeness. Considering the strong interrelatedness of the lock-in mechanisms that guide the actors of the industry, policies may be needed to encourage and support the establishment for more sustainable development.

    Originality/value – A multilevel perspective is used to analyse the type of barriers to innovativeness that the architects perceive as relevant and how they contribute to the resistance to change and path dependency in the building construction sector.

  • 97.
    Hermansson, Sven
    et al.
    SP.
    Backéus, Sofia
    Bohman, Christoffer
    Gulliksson, Hans
    Larsson, Sylvia
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Öhman, Marcu
    Testbädd Mellanskalig Biorbränsleförbränning - en förstudie2014Report (Other academic)
    Abstract [en]

    Conversion of biomass to heat and power plays an important role in the transition of the Swedish energy system from fossil based to renewables. For manufacturers and users of medium scale combustion plants (0.5 – approx. 15 MWth), a spectrum of challenges are accounted with both today’s and future flexible use of modern biomass fuels. Such challenges are e.g. fuel handling and processing together with combustion instabilities caused by new fuels with resulting ware-and-tear and elevated emission levels. However, the possibilities to test and try out new innovations is very limited, which is why a Test Bed has the potential to significantly contribute to the innovation growth within the sector. The purpose of this feasibility study therefore to investigate the prerequisites for the establishment of a Test Bed for Medium Scale Biomass Combustion. The fundament of the feasibility study is a survey of the existing infrastructure for testing and innovation development of medium scale biomass combustion, which could be further developed and interconnected. Furthermore, a broad inquiry has been performed among market actors, focusing on the present and future need together with existing conditions for taking part in the development of a test bed. These first two steps has then been synthesized into recommendations on how a test bed should be developed and exploited by relevant actors. The major conclusions and recommendations of the feasibility study are:  A cost efficient and innovative Test Bed system for medium scale biomass combustion could be developed by enhanced cooperation between passive test-bed like plants and systems, industrial testing plants and research activities,  Development of a test bed system is hindered by the fact that there is no clear receiver of such system on the market. Stake holder cooperation is today weak, which makes common investments and financing impossible  There is no economic support for the erection of new, dedicated test bed facilities for medium scale biomass combustion,  Pre-treatment of biomass raw material with the purpose of enhancing fuel quality simultaneously refining products from the biomass has been found to show good potential for further development of test beds. This study therefore recommends that such investigation should be taken under consideration.

  • 98.
    Holmqvist, Patrik
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Fasth, Arvid
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Energiåtervinning med frånluftsvärmepump i flerbostadshus: Simulering av ventilationsförluster och potentiell besparing, Spättan 12019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Energi är ett ständigt aktuellt ämne, där byggnader står för en stor del av energianvändningen i Europa och Sverige. Samtidigt som energieffektiviseringar genomförs måste ett tillräckligt luftflöde bibehållas i byggnaden för att uppnå en komfortabel inomhusmiljö. Detta medför att en stor mängd energi cirkulerar i byggnadens ventilationssystem. Rapporten innehåller en simulering för att fastställa hur stor del denna är, kontra det totala energibehovet för ett flerbostadshus beläget i Kalmar, Sverige. Resultatet visar att ventilationen står för 35 % av det totala värmebehovet.

    Potentialen för återvinningsbar energi beräknades för att utvärdera hur mycket energi som kan sparas genom att installera en frånluftsvärmepump på ventilationssystemet. Simuleringar visar att vid ett godkänt minimumflöde på 0,35 l/s∙m2, skulle fastigheten kunna vara självförsörjande på värme under sommarmånaderna. Detta innebär att det går att återvinna ca 57 kWh/m2∙år, en reducering av energibehovet med 30 %. Vidare arbete skulle innebära fler mätningar på flöden, temperatur och fuktigheter.

  • 99.
    Hosseinpourpia, Reza
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Parsland, Charlotte
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Utilization of different tall oils for improving the water resistance of cellulosic fibers2019In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 136, no 13, article id 47303Article in journal (Refereed)
    Abstract [en]

    This study was conducted to assess the effect of the pulping by-products crude tall oil (CTO), distilled tall oil (DTO), andtall oil fatty acid (TOFA) on dynamic water vapor sorption behavior, interfiber strength, and thermal stability of cellulosic paper-sheets.The results were compared against those obtained in cellulose papers treated with the conventional petroleum-derived hydrophobicagent hydrowax and in untreated ones. The tall oil treatments caused strong reduction in equilibrium moisture content of the paper-sheets during adsorption and desorption runs. The same trend was noticed for the hydrowax-treated papers, however, it was lesspronounced than the CTO-treated and DTO-treated samples in the relative humidity range of 75–95%. The sorption hysteresis was con-siderably decreased after the treatments. The ultimate dry-tensile strengths of the paper-sheets were significantly reduced by TOFA andhydrowax treatments, while CTO and DTO showed comparable strength as that of untreated control. The ultimate wet-strengths of thepaper-sheets were improved after the treatments. The thermal stability of the specimens was improved by the tall oil treatments, and thehydrowax-treated samples illustrated lower degradation temperature than the untreated control. The results are promising for the use oftall oils as alternative hydrophobic agents of cellulosicfiber-based products, such as wood panels and paper packaging.

  • 100.
    Hulteberg, Christian
    et al.
    Lund University .
    Leveau, Andreas
    Biofuel-Solution AB.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Pore Condensation in Glycerol Dehydration: Modification of a Mixed Oxide Catalyst2017In: Topics in catalysis, ISSN 1022-5528, E-ISSN 1572-9028, Vol. 60, no 17-18, p. 1462-1472Article in journal (Refereed)
    Abstract [en]

    Pore condensation has been suggested as an initiator of deactivation in the dehydration of glycerol to acrolein. To avoid potential pore condensation of the glycerol, a series of WO3supported on ZrO2 catalysts have been prepared through thermal sintering, with modified pore systems. It was shown that catalysts heat treated at temperatures above 800 °C yielded suitable pore system and the catalyst also showed a substantial increase in acrolein yield. The longevity of the heat-treated catalysts was also improved, indeed a catalyst heat treated at 850 °C displayed significantly higher yields and lower pressure-drop build up over the 600 h of testing. Further, the catalyst characterisation work gave evidence for a transition from monoclinic to triclinic tungsten oxide between 850 and 900 °C. There is also an increase in acid-site concentration of the heat-treated catalysts. Given the improved catalyst performance after heat-treatment, it is not unlikely that pore condensation is a significant contributing factor in catalyst deactivation for WO3 supported on ZrO2 catalysts in the glycerol dehydration reaction.

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