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  • 2401.
    Åström, Johanna
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Sammanställning och analys av underhållstoppsprocessen på PM1 och returfiberanläggningen hos Smurfit Kappa Kraftliner Piteå2015Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 2402.
    Öberg, Christian
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. SP Processum.
    Co-combustion of Industrial Biosludge and other Residual Streams in a Bubbling Fluidized Bed: Focusing on reduction of operating and technical problems by analyzing the ash transformation chemistry2016Independent thesis Basic level (professional degree), 300 HE creditsStudent thesis
    Abstract [en]

    Today the use of resources in the industry are not complete to be considered as sustainable from the perspective of nutrient recovery. In the Swedish pulp and paper industry residual streams such as bark, fiber reject and sludge are returned for more sustainable use more frequently. Around 300 000-600 000 tons of sludge is generated every year from different cleaning processes in the pulp and paper industry. About 15 % of that sludge is so called biosludge that is a result from biological water treatment, where large amounts of phosphorus are used. After the cleaning process the total amount of biosludge generated in Sweden each year is estimated to contain approximately 2000 tons of phosphorus (P). The most common way to discard the biosludge today is by incineration, where aspects such as high content of moisture and ash have proven to be problematic. Besides phosphorus, other elements such as sulfur (S), chlorine (Cl) and calcium (Ca) are often found in the biosludge in larger amounts.  

    This study included co-combustion experiments of current residual streams from the pulp and paper mill SCA Obbola AB where the aim was to investigate how the ash transformation chemistry was affected. The residual streams comprised of bark, fiber reject and biosludge which were combusted together with stem wood in a bench scaled bubbling fluidized bed. To investigate if different ash related operating and technical problems could be reduced and if there was potential of phosphorus recycling from the ashes, produced ash and other samples were examined by SEM/EDS.

    The fuel mix from SCA Obbola consisted of large amounts of Ca, S and P relative to more ordinary biomass fuels like stem wood. These elements originated from the biosludge and was confirmed by the fuel analysis. Analysis made on collected samples showed that Ca and P together formed phosphates that either stayed in the bed or was collected in the cyclone which indicated that there could be a potential for recovering phosphorus. Although, the Ca/P ratio in the ashes was too high, which probably leads to that phosphates unsuitable for nutrient recovery are formed.  

    The fiber reject from SCA Obbola contained large amounts of chlorine according to the fuel analysis which was indicated from the results later in the study. During the combustion most of the Cl left the bottom ash via volatilization. It was true for both the fuel blends with and without fiber reject. When larger amounts of biosludge was added to the fuel mix less of the corrosive compound potassium chloride (KCl) was found in depositions and collected fine particulate matter (PM). This was due to that more sulfur was added in the system when the amount of biosludge was increased which lead to that K reacted with SO2 instead of Cl and formed K2SO4. The observed reduction of KCl resulted in; 1) lower amounts of fine particulate matter which means less loaded particulate filters 2) less risk of high temperature corrosion on heat transfer surfaces.

    The general conclusion that could be drawn from this study was that by increasing the amount of biosludge in the fuel blend at already high mixings of fiber reject, problems such as corrosion and fine particulate matter could be reduced. These advantages must be considered to the amount of lime stone needed to be added for reducing HCl from a cost perspective. 

  • 2403.
    Öberg, Malin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Optimerade material för optiska komponenter i koncentrerande solfångare2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The energy consumption continues to increase as the use of electronics and energy consuming equipment increases. The use of fossil fuels has to be phased out for this to be sustainable in the long run while the use of renewable energy continues to increase. A renewable energy source is solar energy but the production of heat and electricity are today very expensive compared to other energy sources and an important task for the solar energy market to grow is therefore to minimize the production cost of the solar collectors while increasing its efficiency to produce heat and/or electricity. One way to convert solar energy into heat is by using solar collectors and electricity can be produced by utilizing the produced heat, or by applying solar cells.

    This thesis aims to recommend a reflective material for the next generation solar collectors from Absolicon and to recommend a commercially available coating for the receiver tube of the solar collector. A market study has been carried out to investigate the cost-related aspects along with the optical and durable aspects for the optical material of the solar collector. Experimental evaluations have been performed to ensure that the optical materials meet the requirements that the supplier promises. The optical properties have been evaluated with advanced measuring equipment at the Ångströmlaboratoriet at Uppsala University and with an infrared camera. The measured values from the infrared camera were in turn used to theoretically calculate the thermal losses of the receiver tubes. To investigate the materials durability the materials were subjected to different climates in a climate chamber and all the tests that has been conducted in this thesis have been carried out both before and after the climate chamber simulation to investigate the materials optical and physical durability. An important aspect of the laminated films is that they should have good adhesive properties even when subjected to high temperatures and high humidity and a method to evaluate this has been developed.

    The result of the thesis shows that aluminum reflectors obtain the best optical results for concentrated solar collectors, but since aluminum is not suitable for the Absolicon solar collector TC160 the recommended reflector material is SF2, which showed good optical, adherent and durable properties which is desirable for a good solar collector and a total reflectance of 92.4 % was obtained. The material that is recommended as a receiver tube is R2 with a measured absorptance of 95.9 %, an emissivity of 17.7 % and the thermal energy loss was calculated to 1055 W. R2 is durable in high humidity and temperatures of 85°C for over 300 hours without the optical characteristics deteriorated. Based on the recommended materials, the next generation solar collectors from Absolicon obtained a theoretical calculated optical efficiency of 76 %. 

  • 2404. Ögren, Yngve
    et al.
    Sepman, Alexey
    Qu, Zhechao
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Schmidt, Florian M.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Wiinikka, Henrik
    Comparison of measurement techniques for temperature and soot concentration in premixed, small-scale burner flames2017In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 31, no 10, p. 11328-11336Article in journal (Refereed)
    Abstract [en]

    Optical and intrusive measurement techniques for temperature and soot concentration in hot reacting flows were tested on a small-scale burner in fuel-rich, oxygen-enriched atmospheric flat flames produced to simulate the environment inside an entrained flow reactor. The optical techniques comprised two-color pyrometry (2C-PYR), laser extinction (LE), and tunable diode laser absorption spectroscopy (TDLAS), and the intrusive methods included fine-wire thermocouple thermometry (TC) and electrical low pressure impactor (ELPI) particle analysis. Vertical profiles of temperature and soot concentration were recorded in flames with different equivalence and O2/N2 ratios. The 2C-PYR and LE data were derived assuming mature soot. Gas temperatures up to 2200 K and soot concentrations up to 3 ppmv were measured. Close to the burner surface, the temperatures obtained with the pyrometer were up to 300 K higher than those measured by TDLAS. Further away from the burner, the difference was within 100 K. The TC-derived temperatures were within 100 K from the TDLAS results for most of the flames. At high signal-to-noise ratio and in flame regions with mature soot, the temperatures measured by 2C-PYR and TDLAS were similar. The soot concentrations determined with 2C-PYR were close to those obtained with LE but lower than the ELPI results. It is concluded that the three optical techniques have good potential for process control applications in combustion and gasification processes. 2C-PYR offers simpler installation and 2D imaging, whereas TDLAS and LE provide better accuracy and dynamic range without calibration procedures.

  • 2405.
    Öhman, Erik
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    BIM i förvaltningsfasen: En studie om möjligheter i förvaltningsfasen av en byggnad med hjälp av en väl utförd informationsmodell2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    BIM – building information modelling or building information model is a well known concept that most people in the construction industry is familiar with and agrees that there is a big potential with this new technology. Despite this, the implementation of this new approach is slow in the industry. Still, BIM is most used before and during the production of new buildings and facilities, while the longest period in a building's life cycle is forgotten, namely the management of the building. New buildings often have a lifespan of over 100 years, which means that maintenance and repairs will be necessary to maintain the requirements of modern buildings. There is potential to facilitate the management of buildings with well-executed information modeling. Today there is a small demand for these well-made models from the management companies and owners of the buildings, they commonly do not acknowledge the benefits of having a building information model to help with their daily work and therefore place no special demands on the various models.

     

    The purpose of this thesis is to find out how information models can be used in the management work of the building and to find out what the projectors can add to the models that are useful in the management work. In order to find out, a literature study has been made to understand the necessary theory and facts and a reference object has been examined to find out how BIM will be used in this particular project.

    The reference object that was used in this thesis was Helios, a part of SCA's new pulp mill in Timrå, outside of Sundsvall, has a detailed model been drawn up and based on this model the necessary 2D drawings is produced and used as the basis for construction. The model does not contain more information than necessary, because few demands have been made on it. The information is gathered in other documents and descriptions used in the production and management. The model that has been drawn up can be exported to IFC format, which means that the model can be opened in the program that can be downloaded for free from the Internet. In these applications, the user can twist and turn the model and look at all details of the building. It is also possible to connect these models with other systems, for example, tabulated values in Microsoft Excel. This makes it possible to obtain an accurate visual representation of the elements of the building while further information can be read by other applications. It is possible for projectors to enter more information in the models. For example, there are links to products' websites, what kind of anti-corrosion treatment a particular element has received and what type of fire protection paint that has been used. The project Helios, the concept of BIM will be lost when the building goes into the management phase as this model will not follow. Flat drawings and a descriptions will be the basis for management work for about 100 years to come. This does not mean that BIM can not be used later in the building's life cycle. It is possible to make a model of the building afterwards, although not all information about all objects is represented in the model or in the associated system. However, in order for BIM to achieve the potential that exists, more requirements must be set in the design phase.

  • 2406.
    Öhman, Marcus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Hedman, Henry
    Eklund, Robert
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Residential combustion performance of pelletized hydrolysis residue from lignocellulosic ethanol production2006In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 20, no 3, p. 1298-1304Article in journal (Refereed)
    Abstract [en]

    As a result of the production of ethanol from lignocellulosic material by acid hydrolysis, a large quantity of non-hydrolyzed material is obtained as a residue, mainly derived from the lignin in the wood. One possible economical use of this hydrolysis residue is as raw material for production of fuel pellets to be used in residential pellet appliances (i.e., stoves and burners). The combustion characteristics of single pellets, as well as combustion results (i.e., ash deposition, maintenance, and emission performance) in residential pellet appliances, were therefore determined for hydrolysis residue pellets and compared with corresponding results using wood pellets. The hydrolysis residue pellets had a lower slagging tendency, as well as a higher heating value and lower ash content, than the wood (stem) pellets. During combustion in residential pellet appliances, relatively similar gaseous emission performance and characteristics were obtained for hydrolysis residue and stem wood pellets. However, the results showed a significant potential for very low emissions of fine particles during combustion of hydrolysis residue pellets because of the low content of volatile inorganic constituents. Tendencies for char-aggregate formation at low temperature ( less than or equal 800 °C) were identified during combustion of hydrolysis residue pellets. A practical implementation of the results in this work, both regarding accessibility and emission performance, is therefore to recommend the use of continuous-feed equipment thereby preserving a high temperature during the whole operation time. Thus, the results show that pelletized hydrolysis residue from lignocellulosic ethanol production could be a very interesting material for future residential pellet appliances designed for this typical biomass fuel.

  • 2407.
    Öhman, Marcus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Hedman, Henry
    Energy Technology Centre, Piteå, Sweden.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Slagging tendencies of wood pellet ash during combustion in residential pellet burners2004In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 27, no 6, p. 585-596Article in journal (Refereed)
    Abstract [en]

    Ash related problems have more than occasionally been observed in pellet burners during the last years. These problems can lead to reduced accessibility of the combustion systems as well as bad publicity for the market. The objectives of the present work were to; (i) evaluate how different raw materials for pellets affect the accessibility of the existing burner equipment, (ii) determine which of the ash forming element(s) that could be responsible for the deposit/slagg formation and, (iii) estimate the critical slagging temperature for the different raw materials. Stored and fresh materials from sawdust, logging residues and bark were used as raw material in three different pellet burners. The results showed that the slagging properties were relatively sensitive to the variations in total ash content and ash forming elements of the fuel. It is therefore recommended that ash rich fuels like bark and logging residues should not be used in the existing residential pellet burners. Both fuel and burner type affected the amounts of ash deposit produced. The degree of sintering (i.e. the strength of the deposits) was mostly affected by the fuel composition. Subsequent controlled sintering test of the produced deposits/slags showed critical slagging temperatures of about 850–900 °C for stored bark and about 1000 °C for fresh bark and stored and fresh materials from sawdust and logging residues. The results further indicated that the Si-content in the fuel correlated (relatively) well to the sintering tendencies in the burners. Chemical equilibrium models were used to interpret the experimental findings, and good quantitative agreements between modelling and experimental results were generally obtained.

  • 2408.
    Öhman, Marcus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Hedman, Henry
    Energy Technology Centre, Piteå, Sweden.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Slagging tendencies of wood pellet ash during combustion in residential pellet burners2004In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 27, no 6, p. 585-596Article in journal (Refereed)
    Abstract [en]

    Ash related problems have more than occasionally been observed in pellet burners during the last years. These problems can lead to reduced accessibility of the combustion systems as well as bad publicity for the market. The objectives of the present work were to; (i) evaluate how different raw materials for pellets affect the accessibility of the existing burner equipment, (ii) determine which of the ash forming element(s) that could be responsible for the deposit/slagg formation and, (iii) estimate the critical slagging temperature for the different raw materials. Stored and fresh materials from sawdust, logging residues and bark were used as raw material in three different pellet burners. The results showed that the slagging properties were relatively sensitive to the variations in total ash content and ash forming elements of the fuel. It is therefore recommended that ash rich fuels like bark and logging residues should not be used in the existing residential pellet burners. Both fuel and burner type affected the amounts of ash deposit produced. The degree of sintering (i.e. the strength of the deposits) was mostly affected by the fuel composition. Subsequent controlled sintering test of the produced deposits/slags showed critical slagging temperatures of about 850–900 °C for stored bark and about 1000 °C for fresh bark and stored and fresh materials from sawdust and logging residues. The results further indicated that the Si-content in the fuel correlated (relatively) well to the sintering tendencies in the burners. Chemical equilibrium models were used to interpret the experimental findings, and good quantitative agreements between modelling and experimental results were generally obtained.

  • 2409.
    Öhman, Marcus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Hedman, Henry
    Energy Technology Centre, Piteå, Sweden.
    Effect of kaolin and limestone addition on slag formation during combustion of wood fuels2004In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 18, no 5, p. 1370-1376Article in journal (Refereed)
    Abstract [en]

    Ash-related problems have more than occasionally been observed in wood-fuel-fired boilers and also recently in wood-pellet burners. These problems can lead to reduced accessibility of the combustion systems as well as bad publicity for the market. The objectives of the present work were, therefore, to determine the effects of kaolin and limestone addition on the slagging propensities of problematic and problem-free wood fuels during combustion in residential pellet appliances (burners), thus contributing to the understanding of the role of kaolin and limestone in preventing slagging on furnace grates. Pellets with additive-to-fuel ratios between 0 and 0.7 wt %d.s. were combusted in three different types of burner constructions (10 kW): over-, horizontal-, and under-feeding of the fuel. The collected slag deposits from the under-fed burner as well as the corresponding deposited fly ash in the boiler were characterized with X-ray diffraction (XRD) and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The initial sintering temperatures of the formed slags were also determined. By adding limestone with an additive-to-fuel ratio of 0.5 wt %d.s. to the problematic stemwood raw material (Si-enriched probably because of contamination of sand/soil), the severe slagging of the fuel could totally be eliminated. Adding kaolin to the problematic raw material gave a minor decrease in slagging tendency of the problematic raw material and a major increase in slagging tendency of the problem-free stemwood raw material. When adding limestone to the problematic raw material, the composition of the formed slag was changed from relatively low temperature melting silicates to high temperature melting silicates and oxides. On the other hand, kaolin addition to the problematic raw material changed the content of the slag from mainly Ca-Mg silicates to be dominated by K-Al silicates which have relatively low melting points. When introducing kaolin to the problem-free raw material, the high temperature melting Ca-Mg oxides react to form lower temperature melting Ca-Al-K silicates. Chemical equilibrium model calculations were used to interpret the experimental findings, and generally good qualitative agreements between modeling and experimental results were obtained.

  • 2410. Öhman, Marcus
    et al.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Grimm, Alejandro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Kofod-Hansen, Marie
    Minskade askrelaterade driftsproblem genom inblandning av torv i åkerbränslen2010Report (Other academic)
    Abstract [sv]

    Resultaten visar att inblandning av typisk starrbaserad bränntorv i salix och rörflen med låg askhalt ger positiva effekter vad avser bäddagglomerering och beläggningsbildning/(korrosion) i pannors konvektionsdelar redan vid relativt låga inblandningsgrader (15 vikts-% på TS basis). En starrbaserad bränntorv med relativt högt Ca/Si förhållande bör väljas för sameldning med salix i rosteranläggningar för att inte öka slaggningsrisken. Samma torvtyp kan också i rosteranläggningar nyttjas i sameldning med rörflen med låg askhalt (relativt låga inblandningsgrader räcker) och vetehalm (höga inblandningsgrader krävs) för att reducera slaggningsrisken. Vid val av torvslag för att maximera de ovanstående positiva effekterna vid förbränning kan därför en allmän rekommendation göras att torvar med hög askhalt (starrinnehållande torv), och gärna med högt inslag av svavel, ger de bästa sameldningsegenskaperna med det tilläget att vid rostereldning bör en torv med relativt högt Ca/Si förhållande väljas (gärna upp mot 1 på vikts-% basis).

  • 2411.
    Öhman, Marcus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Hedman, H
    Jirjis, R
    Reasons for slagging during stemwood pellet combustion and some measures for prevention2004In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 27, no 6, p. 597-605Article in journal (Refereed)
    Abstract [en]

    Ash related problems have more than occasionally been observed in pellet burners during the last years. These problems lead to reduced accessibility of the appliances and also bad publicity for the pellet market. The objectives of the present work were therefore to: (i) determine the critical levels of the problematic ash components in stemwood pellets regarding slagging, (ii) document the variations of these problematic elements in the outgoing pellets from two pellet-mills during one operational season, (iii) determine how frequently these elements exceed the critical levels, (iv) determine how different sub-processes in the pelletising process (especially the dryer) effect the slagging properties of the pellet, and if possible (v) suggest some measures for prevention. A significant number of wood pellets reported to be problematic and problem-free, regarding slagging in ordinary residential pellet burners, were collected from the Swedish market. The ash compositions of these fuels were analysed and the results compiled in a database. Partial Least-Squares Discriminant Analysis (PLS-DA) and F-tests were used to statistically identify both the critical ash components and the critical levels of these components that separated the two reported classes. In addition, chemical equilibrium model calculations were used to interpret the findings. The variations of these elements in the in-going raw material and in the produced pellets were determined during one season in two pellet mills equipped with exhaust gas dryers. The results showed that the problematic wood-pellets had a significantly higher amount of Si, but also Al and Fe, in the fuel ash. The critical level of Si (given as SiO2) was about 20-25 wt% of the fuel ash, i.e. pellets with levels in or over this range resulted in slagging problems in residential burners. This critical Si content was exceeded once and twice for the analysed samples in the two studied pellet mills. In one of the studied mills, this was because of contamination by sand of the raw material during storage and handling, and in the other mill the reason was found to be contamination of the raw material by elutriated particles from the dryer fuel. The major conclusion of the work is that both raw materials and drying fuels/processes should be carefully treated to avoid mineral contamination, and an additional cyclone separator could potentially also be used to improve the pellet quality.

  • 2412.
    Öhman, Marcus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lundholm, Karin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Hedman, Hedman
    Energy Technology Centre, Piteå.
    Lundberg, Margareta
    Kvaerner Pulping AB, Power Division, Göteborg.
    Ash Transformations during Combustion of Meat-, Bonemeal, and RDF in a (bench-scale) Fluidized Bed Combustor2003In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 17, no 5, p. 1153-1159Article in journal (Refereed)
    Abstract [en]

    Following the recent Bovine spongiform encephalopathy (BSE) experiences, thermal treatment of meat- and bonemeal (MBM) in existing fluidized bed combustion (FBC) plants for refuse-derived fuels (RDFs) has evolved as an interesting disposal and disintegration method. However, only a limited number of studies have previously been performed for combustion of MBM in fluidized beds. The objectives of the present work were, therefore, to determine the bed agglomeration tendencies of these materials during combustion in fluidized beds and to evaluate the effects of dolomite and kaolin addition to the fuel mix, as well as to elucidate the overall ash transformation mechanisms governing the potential bed agglomeration and fouling processes. By controlled agglomeration experiments in a 5 kW bench-scale fluidized bed reactor, the fuel-specific critical agglomeration temperatures in normal quartz bed material were determined for the different fuel/additive mixtures. All collected samples of bed materials, final bed agglomerates, and cyclone ashes were analyzed using SEM/EDS and XRD. The results indicated that the MBM fuels could be expected to be problematic concerning bed agglomeration in normal quartz beds, while kaolin and possibly dolomite addition could be used to reduce this risk to moderate levels. A significant elemental fractionation between the bed material and the cyclone ash was obtained. Apatite (Ca5(PO4)3(OH) or potentially some other calcium phosphates are elutriated from the bed and enriched in the fly ash, while sodium and potassium are enriched in the bed material. The characteristics and the corresponding melting behavior estimations of the necks formed between agglomerated bed particles suggest that silicate melts are responsible for the bed agglomeration. Results from XRD analysis of the fly ash formed from the fuels used in the present study indicated that the risk for melt-related fly ash problems seem relatively small.

  • 2413.
    Öhrling, Jenny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    En analys av EPC som modell för energieffektivisering: En djupdykning i energieffektiviseringsåtgärder i Umeå kommuns EPC-projekt för att närmare förstå EPC som projektform vid energieffektivisering2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I detta examensarbete har åtgärder i ett energieffektiviseringsarbete av typen EPC analyserats. Umeå kommuns fastighetsavdelning startade sitt EPC-projekt 2008 syftet att energieffektivisera mer än 130 byggnader. Detta projekt sades då vara det största av sitt slag i Sverige. Bakgrunden till behovet av att utföra detta grundades i att en stor del av de tekniska systemens livslängd i fastigheterna började vara uppnådd samtidigt som ett energieffektiviseringskrav ålades fastighetsavdelningen. Siemens anlitades som entreprenör. De villkor som styrde projektet kom från beslutsfattande politiker och handlade om den viktiga besparingsgarantin. Denna garanti var en förutsättning för att få ekonomiska medel att finansiera ett projekt av den här storleken. EPC som modell valdes för att möjliggöra dessa krav.

    Den data som legat till grund för analysen av de energieffektiviseringsåtgärder som utförts har funnits samlad i eRoom, Siemens plattform för EPC-projekt. Den information som varit mest essentiell har varit de projektutvecklingsrapporter som för varje objekt beskrivit läge, problembild, åtgärdsförslag samt de energikartläggningar som innehållit alla energiberäkningar för energiläget i respektive fastighet samt potentiellt energiläge efter utförande av föreslagna åtgärder. De åtgärder som ansågs relevanta för att på det mest tydliga vis beskriva resultatet av Umeå EPC-projekt beslutades få ligga till grund för att reda ut hur besparingsfördelningen såg ut.

    Resultatet av detta arbete visar att de åtgärder som levererade störst del av den totala besparingen i ren energi var åtgärder kopplade till fläktar samt övriga åtgärder där styråtgärder av motorvärmare, injusteringar och pumpar rymdes. Efter dessa poster var tilläggsisolering samt belysningsåtgärder stora. Vidare vad gäller den ekonomiska besparingen var det konverteringar av uppvärmning som var absolut störst, därefter fläktarbeten samt kategorin övriga poster.

    Den ekonomiska investeringen var svår att på ett rättvist sätt jämföra mot hur stora besparingarna varit per åtgärd. En jämförelse av besparing mot antal åtgärder inom varje kategori visar däremot att konvertering till fjärrvärme samt värmeåtervinning var de mest effektiva åtgärderna. 

  • 2414.
    Öhrman, Rickard
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektivisering av Forsbacka oljesystem2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Skellefteå Kraft owns and operates the district heating network in the town of Lycksele. For this they have two sites, Skogsbacka CHP plant and Forsbacka heating plant. Forsbacka is the smaller plant with four boilers, two wood chip boilers and two that are oil-fired. The Forsbacka plant is mainly used during summer and at peak loads. For storage and supply of oil to the oil-fired boilers there are two 100 m3 cisterns. The oil system is old and built for heavy oil, which means that the oil has to be kept at minimum temperature of 35°C

    The aim of this report is to examine possible measures to make the storage and handling of the oil more energy and cost efficient.

    The results show that it would be a good idea to change to light oil and thus be able to lower the oil temperature to at least 20°C. This would halve the cost for keeping the oil warm, whereas an increased insulation of the cisterns would not be cost efficient. Another recommended measure for energy saving would be to install frequency converter for speed regulation of the oil pumps, which would reduce the energy use to halve.

  • 2415.
    Ölund, Andreas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Informationslager för stora mängder SNMP-data2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    TeliaSoneras internet operations center has a great need to quickly collect statistical data of nodes and costumer connections, collected data is then used to troubleshoot and repair problems in the network. To secure a reliability and quality that is demanded, one of the systems need to be further developed. The application that has been developed is intended to improve the collection and storage of the statistical data to speed up the quality analysis of the xDSL network. Requirements of the application development are that the collection, conversion and storage are that all parts should be horizontally scalable. During development of the application, concepts like multithreading, message queues, messaging patterns, JSON/BSON and NoSQL has been acquired. Results of the project are a prototype written in PHP. Its function is from a messaging pattern where a Client reads an file containing connection data. The Client then serializes this data and sends a request to the Job server. The Job server then receives the request and sends the workload to a ready Worker. The Worker receives the workload and deserializes the connection data. The Worker connects to the node specified in the request from the client and collects the SNMP-data and makes error checks before the Worker returns the results to the Client. In the end of the report future work is discussed of how the prototype can be further developed to be implemented in a production level.

  • 2416.
    Ölund, Viktor
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Mobilapplikation för driftinformation och analysverktyg2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    TeliaSonera has many subsystems to analyze the quality of TeliaSonera's network. Some of the main subsystems is ADSL-analys and Mibview.

    An ADSL analysis shows the current status of sync, broadband speeds, bit error, signal-to-noise ratio, attenuation and retrains on customers in TeliaSonera's network.

    Mibview is a measurement which lasts for three days and demonstrating graphs in different categories, the graphs show data minute by minute during the day the measurement is made. Some of the most commonly used graphs of the analysis is

    IfOperStatus -Displays the status of the sync

    CurrBrAtuc -Sync speed

    Curr24CvAtuc -Incoming bit error

     

    Today TeliaSonera's technicians have a great need to use these subsystems to take quicker decisions when technicians are working on customer assignments.

    Currently the subsystems exists in the form of technical support in computer systems.

     

    The requirement of the project is therefore to develop an application that receive these subsystems to TeliaSonera technicians.

    The conclusion of the project is a mobile application developed in android operating system with the subsystems ADSL analys and Mibview, where technicians voluntarily can utilise the subsystems.

    The mobile app is designed to execute requests against scripts in servers to retrieve stored data from databases.

    In the end of the report there are mentioned suggestions for improvements of the app to be deployed in production.

  • 2417.
    Önnerlöv, Jonathan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Montageplattform: För inredning av två vertikala ventilationsschakt i Garpenbergs gruva2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company Bergteamet, Boliden, Sweden, is installing ventilation shafts of the Garpenberg mine. For such work a platform is needed which you can stand on and work from. The Shaft Reinforcement Team at Bergteamet performs the installation work and is the sponsor of the platform. The project described in this report is performed at the department MEC, Mining Equipment Construction, which has been given the task to design and construct the platform, customized for the current shaft. After this the platform is manufactured and inspected at the workshop at Bergteamet.

    The design work was carried out as follows:

    - After an initial meeting a requirement specification was worked out, describing the problem and previous experiences of platforms and requirements for the design and equipment.

    - A concept sketch was developed with consideration of surrounding factors.

    - A constructed 3D model was presented along with the choice of materials. Improvements were made after feedback from Bergteamet.

    - Development of production drawings. The drawings were reviewed and handed over to the preparer for manufacturing.

     

    The result was a platform designed with different square tubes where the floor follows the geometrical shape of the shaft. The platform is suspended from a rectangular center tube with dimensions 100x100x8, which is centered in the shaft. The purpose of a center tube is that it facilitates the final stage of the work in the shaft, namely the installation of a fall protection. The platform has a roof to protect from stone rain and dripping water. Under the floor is an air tank places to run the air-powered outriggers. Around the workplace there is a guardrail with a door for access and egress. The design work was done using the drawing program SolidWorks. Calculations were made by hand.

    The platform fulfills the requirements defined by the trade organization for mine elevators in Sweden, (BRAGS), as well as Bolidens for the design and Bergteamets internal design requirements. The platform has been manufactured, inspected and soon filled its purpose for the shaft installation in the Garpenberg mine.

  • 2418.
    Örberg, Håkan
    et al.
    Sveriges Lantbruksuniversitet, Enheten för Biomassateknologi och Kemi.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Grimm, Alejandro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Öhman, Marcus
    Teknikutveckling för ökad etablering och nyttjande av rörflen: Demonstrationsförsök i fullskala2010Report (Other academic)
    Abstract [sv]

    Resultaten visar att energigräset rörflen kan utgöra ett kompletterande bränsle till det skogsbränsle och den torv som idag används i svenska värme- och kraftvärmeanläggningar. En inblandning av rörflen med ca 10 % på energibasis i en bränslemix som för övrigt består av 10-20 % carextorv och 70-80 % träbränsle har i demonstrationsförsök visat goda resultat. Denna bränslemix har vid fullskaliga förbränningsförsök i fluidiserande bädd (Hedensbyn,CFB 98 MW) under sammanlagt 4 dygn inte gett upphov till störningar eller negativa effekter på utrustning eller ökade utsläpp i rökgaserna i form av partiklar eller gasformiga emissioner. Vid simulerade påverkan på överhettare i form av kylda sonder har även konstaterats att beläggningstillväxten varit oförändrad och ej givit upphov till ökad korrosion.

    Inblandning i bränslemixen har skett med hackad rörflen (40-50 mm) i torvdelen för att en jämn inblandning kunde åstadkommas. Rörflensmaterialet har levererats i samband med skörden så att det hackats direkt på fältet med exakthack kopplad till vagn eller med containerhantering. Vid leverans under vår och försommar har rörflenen hållit mycket låg fukthalt med ett medel på 11,3 % fukt. Jämförande studier har gjorts med system där rörflen vid skörden under vår pressats till storbalar för vidare transport till terminal eller gårdscentrum. Detta system har visat sig mindre effektivt jämfört med direkthackning på fältet och transport av hackat material till värmeverk. En fördel med storbalssystemet är dock att det möjliggör mer kostnadseffektiv lagring utan att t.ex. fukthalten höjs under lagringstiden. Även vägtransport från terminal eller gårdscentrum till värmeverk har visat sig mer effektivt med storbalar jämfört med hackat material. Vid lastning av stora fyrkantsbalar (90x120x220 cm) på lastbil med släp uppnåddes i stort sett dubbla lastvikten jämfört med hackad rörflen (20,9 ton jmf. m. 11,0 ton).

    För de något mindre anläggningarna av typen rosterpannor som provats (0,6 och 4 MW) har den briketterade formen av rörflen använts för att uppnå en jämn och koncentrerad bränslematning. Även här har en blandning av rörflen och torv visat sig användbar och speciellt för rörflen med låg askhalt har torvinblandning på 15 vikts-% av gett minskad tendens till sintring av askan. Rörflen med hög askhalt (utan torvinblandning) har kunnat sameldas med träbränsle utan risk för sintrad aska i dessa anläggningar. Tillverkningen av briketter för försöken, sammanlagt ca 35 ton, varav hälften med inblandning av torv har genomförts utan störningar och med bra kvalité på briketterna.

  • 2419.
    Örnberg, Johan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Fartygsanslutningar till landströmsnätet I Umeå hamn2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When ships are at dock they burn their fuel to generate electricity onboard, causing air and noise pollution in the port area. The pollution obtains negative effects on people, the environment and gives the community high costs. One solution to reduce these pollutions is to connect the ships to the on land electrical grid; this method is called cold ironing. To see if this is a solution the grid owner Umeå Energi has to investigate the condition of the grid for ship connection.The thesis is done with a background of six ships on three wharves with a power requirement of 3,755 MVA. The report suggests two potential solutions for engaging the shore, one with the wind power cable and the other with the nearest grid for the ports. The investigation showed a strong grid and an expansion of the grid for the cold ironing would need an investment for 800 thousand up to 1,7 million Swedish kronor, depending on the choice of solution. To find out the benefits for cold ironing in the area for environmental and social cost reduction. There is three wind power plants near Umeå harbor and they produced year 2014 13, 9 GWh, while the estimated energy consumption for the vessels is at 3, 95 GWh. Wind energy production is not continuous and other energy sources is needed. The cables in the harbor are connected to Holmsund distribution station which can supply the vessels at low wind power production. When connected to shore power the price of electricity for ships is less expensive when cold ironing instead of on board generation.Emissions at the shore could reduce to over 98% compared with fuel generated electricity. The reduction in emissions provides economic savings through lower social costs due to better health for people, the environment and nature. This proves that cold ironing can help to greatly reduce emissions in areas around the port and reduce costs.

  • 2420.
    Örnberg, Lina
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Effektivisering av byggservice, PEAB2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    All businesses in today’s society are constantly striving to develop their agency to keep up with the competition. For a company to be among the best in the industry, they must not only keep pace with the others, but also lead the development. This work has been about increasing Peab byggservice opportunities to be among the best, using only simple instruments. The focus has been on developing equipmentthat can simplify the documentation of materials, machines and hours worked, but also the management of trailers. It has also been on developing technical facilities and organizing the storage area that is connected to building service. Some parts work in the current situation quite well while others do not. In order to achieve better results within a business you have to both streamline what works good and bad. With the streamline new features was developed such as templates, forms and agreements, in order to simplify the work of supervisors in terms of summaries and compilations of the project. In addition there were also technical instruments in form of apps developed to digitize a large amount of project information that supervisors need access to. This proved to give a very positive effect in supervisors’ daily work, with better access to information and greater flexibility. In addition, a disposition-drawing plan was created to improve conditions so that in the future larger amount of materials can be bought and stored within their own premises. By buying larger bathes of materials it’s easier to keep expenses for material and transportations down, resulting in a more efficient use of resources and assets. These facilities will serve as basis for a more effective and progressive way of working in building services.

  • 2421.
    Östergren, Simon
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energiutredning av en hälsocentral samt förbättringsarbete av modulen Energi & Miljö i DeDU2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Byggnadssektorn är en av de tre största områdena inom världens energianvändning och den står för ungefär en tredjedel av den totala energianvändningen. Det är därför av stor vikt att byggnadssektorn effektiviseras för en mer hållbar framtid.

    I det här examensarbetet var syftet att utföra en energiutredning på en hälsocentral med hjälp av energistatistik från modulen Energi & Miljö i WSP:s egenutvecklade programvara DeDU. Den andra delen i arbetet var att med erfarenheter från energiutredningen undersöka hur modulen Energi & Miljö kan förbättras för att bättre uppmärksamma dess användare på energianvändning.

    Energiutredningen utfördes med hjälp av konstruktionsritningar och energistatistik från DeDU för total fjärrvärmeanvändning, total elanvändning samt timvärden för elanvändningen. Fördelning mellan fastighetsel och verksamhetsel togs fram med hjälp av statistik från studien STIL2 utförd av Energimyndigheten. Det visade sig att Hörnefors hälsocentral är relativt energieffektiv sett till andra liknande fastigheter. Byggnadens klimatskal visade sig vara bra med ett Umedel på 0,45 W/m2K. Av de energieffektiviseringsförslag som togs fram visade det sig att förslaget med störst besparingspotential är byte av 2-glasfönster till 3-glasfönster.

    Förbättringsarbetet av modulen Energi & Miljö i DeDU utfördes genom en enkätundersökning, en workshop samt en undersökning av befintliga energirapporter för att ta fram förslag på nya rapporter. Från enkätundersökningen framkom det att de tillfrågade kunderna generellt är nöjda med modulen Energi & Miljö men att det finns önskemål om en del förbättringsförslag. Tre förslag på nya energirapporter kopplade till DeDU togs fram. Huvudsakliga tanken bakom förslag 1 och 2 var att ge kunderna möjlighet att lättare göra jämförelser mellan olika fastigheter/byggnader samt jämförelse av energianvändningen för samma fastighet/byggnad. Tanken med förslag 3 var att ge möjlighet att uppskatta olika verksamheters fördelning mellan fastighetsel och verksamhetsel. Slutligen kan det konstateras att det är fördelaktigt att presentera färdig förbättringsförslag, då de flesta kunder inte själva vet vad de behöver eller vad som saknas.

  • 2422.
    Österlund, Patrik
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Förändrat körsätt av sodapannan2014Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    The student thesis has been carried out for five weeks at Smurfit Kappa Kraftliner in Piteå. The project assigned was to perform a change in their driving behaviour of the combustion air to the recovery boiler and eventually minimize problems with dust departure. The method of the experiments was to close the 1,1 MPa steam and only inject 0,3 MPa steam to the air preheater before injection into the recovery boiler. The purpose of the thesis was to analyse the experiments and evaluate if there are any negative consequences to run the plant with only 0,3 MPa steam. The computer program WinMops was used to evaluate how the facility had been running earlier in the year and then compare this with the results of the experimental runs.

    The purpose of the recovery boiler is to recover chemicals by burning black liquor and to produce overheated steam to the turbines. The control and driving style of the recovery boiler is important for the black liquor combustion to be optimal. The combustion depends on the composition of the black liquor and the combustion air that is added. With the right amount of air and in the right places, you can control how well the combustion will be depending on the composition of the black liquor. Therefore, the combustion air is inserted to the recovery boiler at four different levels.

    Combustion tests were performed on two occasions, 24 hours each, and resulted in many negative consequences. The degree of reduction of green liquor and outgoing steam quantity was reduced. The amount of air into the boiler increased when the air pressure went down as the temperature of the combustion air was lowered from 170°C to 132°C. Increased amount of air in the boiler led to increased amount of fumes, which had a negative effect on the dust departure.

    The conclusion from this study is that the problems of high dust departure continued even with the changed driving behaviour of the combustion air. The conditions for combustion experiments have not been optimal when a number of breakdowns occurred in the steam network. The results probably had become more reliable with longer trial periods because the black liquor composition varies from day to day. 

  • 2423.
    Östin, Ronny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektivt byggande i kallt klimat2012In: Bygg & teknik, ISSN 0281-658X, Vol. 104, no 8, p. 39-42Article in journal (Other (popular science, discussion, etc.))
  • 2424.
    Östin, Ronny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Evaluation of a Single Family Low Energy Building in Cold Climate2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 132, p. 9-14Article in journal (Refereed)
    Abstract [en]

    Verification of energy performance and indoor climate by detailed field measurements in buildings is of great importance and promotes an assurance in the process of constructing low energy buildings and enables to utilize the full potential of energy efficiency measures.

    In the present work a single family building with a heated living space area of 175 m2 has been monitored. The heating system has a wood pellet stove for space heating (SH) and domestic hot water (DHW) and on the roof there are solar collectors in a southerly direction contributing to SH and DHW. SH is distributed by the ventilation system and an under floor heating system which is connected to a heat storage water tank. The incoming outdoor air is pre-heated in an earth-to-air heat exchanger and the building has a measured specific energy usage of 54 kWh/m2year which is far lower than today’s regulation at 130 kWh/m2year in the actual climate zone. The low energy use in the building are due to thick thermal insulation (average Um = 0.18 W/°C m2), an air tight envelope (q50 = 0.165 l/sm2), heat recovery of exhaust air (average 74 % efficiency) and free heat from the ground pre-heating of supply air which is above 2°C even for outdoor temperatures down to -27°C. An essential factor was the low rate of air changes during the heating season about 40 % of the regulated requirement. Measurements of indoor air quality like carbon dioxide occasionally indicated insufficient ventilation.

  • 2425.
    Östin, Ronny
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Eklund, Erik
    Johansson, Christer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektivt byggande i kallt klimat2012Report (Other academic)
    Abstract [en]

    The project Energy efficient construction in cold climate is a study of six newly produced low energy buildings in the region of Umeå. Four buildings are houses and two residential buildings which are located from Sikeå up north to Nordmaling down south.

    The buildings have been equipped with wireless logger system for collecting data of energy performance for the entire building and for individual components of the energy system. Loggers for relative humidity and temperature have been placed in ventilation and the buildings construction shell. The later of the position of loggers have been placed in different depths of the constructions isolating shell.

    The purpose of this study is to investigate these buildings energy performance and what risks constructing energy efficient buildings in cold climate due to humidity. The relative humidity and temperature sensors located in the construction shell show no signs of risk for rotting and mold. Moisture migration is a slow process and to be certain longer measurements are required.

    With the method called energy signature the measured energy usage have been normal corrected by year and the average U-value calculated. Expected energy usage and average U-value is compared to our measured data in this report.

    Two buildings in the study are equipped with a buried pipe for supply air which is 36m and 10 m long. The longest (36m) shows a big increase of air temperature (from -25°C outside to +°2 at the inlet connecting to the heat exchanger). This by means no extra heat is required for the inlet air to reach comfortable temperature.

    The measurement of energy displays that constructing buildings with lower energy use then the Swedish Boverkets requirements are confirmed. The houses shows a specific energy usage as Boverkets definition (energy for heating and for domestic hot water per heated surface area) from 59.7 to 91.8 kWh/m2, year and the residential buildings from 68 to 75.5 kWh/m2, year which are lower than today regulations at 130 kWh/m2, year and 95 kWh/m2, year for electric heated.

  • 2426.
    Östin, Ronny
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nair, Gireesh
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energy performance and lessons learned from detailed measurement of a passive house preschool in cold climate2019In: Is efficient sufficient?: eceee 2019 Summer Study on energy efficiency: Abstracts, European Council for an Energy Efficient Economy (ECEEE), 2019, p. 1433-1442Conference paper (Refereed)
    Abstract [en]

    Public passive house buildings are rare in high northern latitudes. This study reports on extensive measurements and evaluations of the most northerly (640 N) built passive house preschool in Sweden. The two storied preschool, built in 2014, has a total heated floor area of 1407 m2. The building was certified according to the international passive house standard. The building has several smart solutions such as demand controlled ventilation of individual rooms and automatic solar shading system.

    Energy measurements conducted during 2017-2018 showed that the preschool annually uses 44.4 kWhm-2, which is approximately 25 % lower than the passive house requirement for energy demand. However, the annual specific space heating requirement of 15 kWhm-2 and the peak heat power demand of 10 Wm-2 were not fulfilled. This non-compliance was mainly due to excessive ventilation during the heating season which was found to have 2.7 times higher air changes than the requirement in the Swedish building code. Furthermore, the building was found to be over heated from the sun during several occasions in a year. For example, excessive indoor air temperatures in the range 28 – 31°C were found during summer.

    The study revealed that the default winter operation by turning off the ventilation system during nights and weekends is continued in other seasons as well. This practice was not a “smart” approach for the air handling units as it was found to be one of the reasons for high indoor temperatures during non-winter months. Also, a mismatch between the operation of the automatic shading device and the ventilation control units was noted.

    The investigation shows that smart technical solutions in buildings may not be able to deliver its’ promised results if such systems are not monitored, adjusted and carefully evaluated. The paper identifies areas that need attention to ensure that a public building built to passive house standard actually deliver the energy efficiency it promises.

  • 2427.
    Östling, Ida
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Life cycle analysis as a tool for CO2 mitigation in the building sector2018Independent thesis Advanced level (professional degree), 300 HE creditsStudent thesis
  • 2428.
    Östling, Ida
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Life cycle analysis as a tool for CO2 mitigation in the building sector2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    After the Paris agreement 2015 the Energy Commission in Sweden proposed a goal for Sweden of net zero greenhouse gas emissions by 2045. The focus in this report has been on how buildings in Sweden could reduce their greenhouse gas emissions. Year 2017 the government gave a task for Boverket in Sweden (National Board of Housing, Building and Planning) to investigate the possibility to introduce a climate declaration on buildings. The idea is a life cycle analysis (LCA) should be performed on the building in order to get a building permit. An LCA include all CO2 emissions emitted from resources used for raw material extraction, production of materials, construction site operations, user phase and also the demolition and disposal in the end of life of the building. The first draft from Boverket was published in February 2018 where they recommended a simple declaration. They recommended in the beginning to only include a few components in the declaration, and to only include the production phase. The major interest in this report have been to gain more understanding on how to perform LCAs and also how the LCA result could be used to decrease CO2 emissions. A case study was made on a residential building project called Mården, in Umeå Sweden.

    The first part in this thesis was to determine the phase in the buildings life cycle with the largest potential for decreasing CO2 emissions. When the LCA was performed on case study building Mården it was difficult to use exact data, since only 20 % of the construction products where declared in an environmental product declaration (EPD). Therefore the other 80 % where approximated with similar products declared in an EPD, or with generic data (general data for a type of product). An EPD is an LCA on a single product and could therefore give exact information on CO2 emissions for a specific product. However, several improvements where implemented in the buildings life cycle and where compared with this reference case. The result from the LCA showed the energy use in the user phase emitted the largest amount of CO2 emissions, and therefore also where the phase with the largest potential for reducing CO2 emissions. When the Swedish district heating mix where replaced with an energy source with 50 % less CO2 emissions, the emissions for the whole life cycle could be decreased with 20 %. Smaller improvements such as more environmental friendlier concrete, shorter transport distance between manufacturer and construction site or less water usage resulted in a decrease by 1.6-7 %. It was though shown these smaller improvement could result in a large decrease of CO2 emissions if more buildings also would improve the same thing. 2.4 million tons of CO2 emissions could for example be reduced in Sweden if 50 % of Sweden’s all new building projects would improve their choice of concrete. To make sure buildings could reduce their CO2 emissions there is important LCAs are performed before the building is constructed, to make sure all phases in the life cycle can be improved. If an LCA will be performed when the building is constructed, it is only possible to improve a few parts in the user phase, since the other phases already have passed.

    The second part in this thesis was to compare the different LCA softwares; (i) One Click LCA (needs license, from Finland), (ii) e-tool (free, from Australia) and (iii) BM (free, from Sweden). When more exact data were tried to be used in e-tool and One Click LCA the results were similar for the CO2 emissions from the production phase. E-tool only resulted in 6 % higher CO2 emissions in the production phase than One Click LCA. The LCA in the eventual future climate declaration will probably be performed with generic data, since in an early stage the contractors will not have detailed information on their construction products. An LCA was thus performed in each software with generic data, and the result differed a lot. The CO2 emissions from the production phase resulted in 36 % and 23 % less CO2 emissions in BM and e-tool than in One Click LCA. If several softwares will be allowed in this eventual climate declaration, the judgment could be difficult since different generic data is used in each sofware. The generic data were also different for one type of product in a single software, where the CO2 emission could differ with as much as 50 % between two types of generic data for one type of products. This leads to a difficulty when choosing generic data since there will be lack of information on the construction products at the time when this eventual climate declaration should be performed. A main focus for the future development should be on evaluating a standard database that could be used in EU.

    If a future law will be implemented it could be valuable to declare detailed rules on how to perform the LCA. Since depending on who will perform the LCA different results could occur due to different data used or assumptions on things like products, boundaries or used resource. However, this master thesis has shown there is possible to use the LCA methodology to find solutions for decreasing the CO2 emissions for buildings.

  • 2429.
    Östlund, Joel
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lastarmsstöd till frontlastare: Konstruktionsförslag för ett nytt lastarmsstöd till Ålös frontlastare2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Ålö AB, situated in Brännland outside of Umeå is one of the world’s leading suppliers of agricultural machinery. A key product in Ålö’s product range is the front loader that is sold under the brands Quicke and Trima. The front loader has many areas of use. One use for the front loader is for plowing snow, a situation which puts the loader under a heavy load to the sides. This is something the loader isn’t built for. To combat this issue, Ålö has developed a beam support that gives the front loader support. The current solution has been around for about 25 years and was made with the prerequisites available of that time. Progress in the fields of computer assisted product development has rendered this solution somewhat outdated and in need of a modern replacement.

     

    The goal of this project was to deliver two concepts for a new beam support and the supporting documentation necessary for a production. The new concepts are made through an analysis of the current solution, discussions with customers and experts in the field, product development with CAD and strength evaluation with the finite element method.

     

    This report handles the product development that ended in two concepts for a new beam support. One concept stems from the old solution and one that draws inspiration from other competing products on the market. The results of this project can be used as a basis and an inspiration for further development.

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