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  • 151.
    Morgalla, Mario
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Benzene-char conversion and particle-vapor characterization in biomass gasification2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biomass is increasingly attracting attention as an alternative to fossil fuels. Gasification permits the thermochemical conversion of biomass into a product gas rich in carbon monoxide and hydrogen. The product gas can be further processed to generate heat, electricity, synthesis gas, chemicals, and biofuels. Particulate matter (PM), inorganic and organic (tars) impurities are formed as contaminants in the gasification process. In this thesis PM and tars formed during atmospheric fluidized bed biomass gasification are characterized and the conversion of a model tar compound (benzene) using a biomass based char aerosol in high temperature (HT) applications is investigated.

    PM in the product gas of a steam-blown atmospheric bubbling fluidized bed gasifier was characterized for mass size distribution and concentration, morphology, and elemental composition. The hot product gas was extracted using a HT- dilution probe combined with a primary and a secondary thermodenuder to adsorb tars and investigate the volatility/thermal stability of the remaining aerosol, respectively. Size distributions with three distinct modes were established. The fine and intermediate modes were mainly formed by tar and alkali vapors that had condensed in the sampling and conditioning systems. The coarse mode mainly consisted of the original particles, which are char, fly ash, and fragmented bed material. The presented PM sampling and conditioning system also showed the potential for online monitoring of heavy tars.

    The tar conversion performance of finely dispersed char particles within a HT-filter and an Al2O3 bed were tested experimentally using benzene as the model-tar. Benzene plus steam (or CO2) were simultaneously supplied to a tubular ceramic reactor that was heated electrically. Fragmented char particles were suspended and continuously supplied via a separate supply line. A HT-filter or a packed bed of crushed Al2O3 balls was positioned in the reactor to retain the char particles. The benzene conversion in the so formed hot char bed was investigated by varying the temperature of the filter or bed, gas flow rates, benzene concentrations, gasification media, char type, char mass and char concentration.

    Increasing the ratio of the char mass and gas flow rate (also referred to as char weight time) enhanced the benzene conversion. This was accomplished by increasing the supplied char concentrations, reducing the gas flow rates or slowing the char gasification reactions. The latter was achieved by lowering the steam concentrations or changing the gasification medium from steam to CO2. Increasing the temperature of the Al2O3 bed did not only raise the char gasification rate and thus reduce the char weight time but also showed to enhance the specific benzene conversion activity of the woody char samples. However, in the 900−1100 °C temperature range, the combined effect was to lower benzene conversions at higher temperatures. The apparent rate constant of the benzene conversion was slightly higher when CO2 rather than steam was used as the gasification medium. Increasing the benzene concentration slightly reduced the benzene conversion. Activated carbon pellets showed higher benzene conversions compared to a pine wood char which was related to the higher specific surface area of the activated carbon pellets. In contrast to a commercially available barbeque charcoal made from broadleaf wood, steam-activated woody charcoal converted benzene even in the absence of steam. This was probably due to the earlier steam activation of the woody charcoal and thus higher microporous surface area compared with that of the barbeque charcoal. Doping the woody barbeque charcoal with approximately 0.7 wt. % iron or 2 wt. % potassium did not improve the specific benzene conversion of the char. For a certain char concentration, however, the doping increased the char gasification rate, leaving less char in the packed alumina bed, thus leading to overall lower benzene conversions.

  • 152.
    Morgalla, Mario
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Seemann, Martin
    Chalmers University of Technology, Sweden.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Characterization of particulate matter formed during wood pellet gasification in an indirect bubbling fluidized bed gasifier using aerosol measurement techniques2015In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 138, p. 578-587Article in journal (Refereed)
    Abstract [en]

    This study characterizes particulate matter, organic compounds, and inorganic compounds formed in an atmospheric indirect bubbling fluidized bed gasifier at two different steam-to-fuel ratios using wood pellets as fuel. The sampling and conditioning system consisted of a high-temperature dilution probe to quench aerosol dynamics and condense inorganic vapors, a primary thermodenuder to adsorb tar components, and a secondary thermodenuder to investigate the volatility/thermal stability of the remaining aerosol. Both online and offline instruments were used to characterize the aerosol in terms of number size distribution, mass size distribution, particle mass concentration, particle number concentration, morphology, and elemental analysis. Size distributions with three distinct modes were established. The fine and intermediate modes were mainly formed by tar and alkali vapors that had condensed in the sampling and conditioning systems. The coarse mode mainly consisted of the original particles, which are char, fly ash, and fragmented bed material. At the higher steam-to-fuel ratio, tar components seem to be reduced and more coarse-mode particles emitted compared to the low steam case. Furthermore, a possibility for online monitoring of heavy tar is suggested. (C) 2015 Elsevier B.V. All rights reserved.

  • 153.
    Morgalla, Mario
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Benzene Conversion in a Packed Alumina Bed Continuously Fed with Woody Char Particles2018In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 32, no 7, p. 7670-7677Article in journal (Refereed)
    Abstract [en]

    This Article investigates the decomposition of benzene (as a model tar) over finely dispersed char particles continuously distributed into a packed bed. Fragmented char particles and benzene plus a gasification agent (H2O or CO2) were supplied into a ceramic reactor that was heated electrically. The supplied char particles were retained in the reactor by a bed of alumina grains. Woody char as well as iron-doped and potassium-doped woody char were used. The influence of the gasification agent, char concentration, char weight time (proportional to the instant char mass present in the bed), and bed temperature (600-1050 degrees C) was investigated. Increasing the char concentration and char weight time increased benzene conversions for all tested chars. At similar char weight times, the benzene conversion increased with temperature, whereas the iron- and potassium doped char did not affect the specific conversion. At similar char concentrations, changing the gasification agent from CO2 to steam as well as using doped char led to decreased benzene conversions. This can be explained by accelerated char gasification reactions and thus a diminished char mass in the packed bed. Furthermore, benzene conversion rates were enhanced in the presence of CO2 as compared to steam. As the temperature was increased from 950 to 1050 degrees C, the benzene conversions were slightly reduced. This was interpreted as a combined effect of the enhanced benzene conversion rates and reduced char weight times. The highest benzene conversions achieved in the experiments were approximately 80% at 950-1000 degrees C using CO2 as gasification agent and supplying approximately 20-30 g N m(-3) undoped woody char.

  • 154.
    Morgalla, Mario
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Benzene conversion in a packed bed loaded with biomass char particles2018In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 32, no 1, p. 554-560Article in journal (Refereed)
    Abstract [en]

    This study investigates the conversion of benzene in a packed bed containing fine char particles. Benzene and steam were simultaneously supplied to a tubular ceramic reactor that was heated electrically. Fragmented char particles were suspended and continuously supplied via a separate supply line. A packed bed of crushed alumina balls was positioned in the reactor to retain the char particles. The benzene conversion in the hot char bed was investigated by varying the bed temperature (900–1100 °C), steam concentration (0–27 vol %), and char concentration (5–50 g Nm–3). The highest conversions achieved in the experiments were approximately 75%. At comparable char concentrations, similar benzene conversions occurred at 900 and 1000 °C. Increasing the temperature to 1100 °C or increasing the steam concentration reduced the benzene conversion. The results indicate that the reduced conversion was due to enhanced char gasification reactions at elevated temperatures and steam concentrations and thus to reduced char mass in the packed bed.

  • 155.
    Morgalla, Mario
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Characterization Of Particulate Matter In Biomass Gasification2015In: Proceedings for the 23rd European Biomass Conference and Exhibition / [ed] I. Obernberger, D. Baxter, A.Grassi, P.Helm, ETA-Florence Renewable Energies , 2015, p. 664-667Conference paper (Refereed)
    Abstract [en]

    The purpose of this work is to examine the potential of monitoring heavy tar compounds contained in the product gas of a biomass gasifier. The hot product gas from atmospheric indirect bubbling fluidized bed gasification of wood pellets was extracted. The sampling and conditioning system consisted of a high-temperature dilution probe, a primary thermodenuder and a secondary thermodenuder. Online and semi-online instruments were used to characterize the aerosol in terms of number size distribution and particle mass concentration. The fine mode (mobility equivalent diameter db < 150 nm) was found to mainly consist of heavy tar compounds. An Electrical low­pressure impactor (ELPI) was used to measure this mode with a time resolution of 1 second and thus showed the potential for online measurements of heavy tar.

  • 156.
    Morgalla, Mario
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Decomposition of benzene using char aerosol particles dispersed in a high-temperature filter2017In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 118, p. 1345-1352Article in journal (Refereed)
    Abstract [en]

    In this study the tar-removal suitability of char particles finely dispersed in a high-temperature filter was investigated. Benzene was selected as the model tar. An aerosol-based method was designed and used to investigate the benzene decomposition behaviour. Two types of char were used: commercially available activated charcoal and pine char prepared in the laboratory. The conversion behaviour of both chars was investigated in the temperature range between 750 and 900 °C using steam as the gasification medium. During the experiments, different benzene concentrations, amounts of deposited char and gas residence times were tested. The results indicate that both activated carbon and pine char reduced the benzene concentration. Activated carbon generally produced higher and more stable benzene conversions compared to the pine char particles. Decreasing the benzene concentration or increasing the gas residence time or char mass improved the benzene conversion. It was concluded that the char gasification rate became slower while benzene was simultaneously converted. The aerosol-based method was also used to investigate benzene decomposition behaviour while continuously supplying fresh char particles together with steam at 1000 °C. In that way, the deactivated and gasified char particles were steadily replaced, preventing the benzene conversion from decreasing over time.

  • 157.
    Mukherjee, Debasis Pradip
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Univ Calcutta, India .
    Molla, Atiar Rahaman
    CSIR Cent Glass & Ceram Res Inst, India.
    Das, Sudip Kumar
    Univ Calcutta, India.
    The influence of MgF2 content on the characteristic improvement of machinable glass ceramics2016In: Journal of Non-Crystalline Solids, ISSN 0022-3093, E-ISSN 1873-4812, Vol. 433, p. 51-59Article in journal (Refereed)
    Abstract [en]

    The influence of MgF2 on the various properties like crystalline behavior, microstructure phases, hardness etc. in the SiO2-Al2O3-MgO-K2O-B2O3 glass system has been investigated. Three batches of glass system were synthesized and characterized by differential scanning calorimetry (DSC), coefficient of thermal expansion (CTE), X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) equipped with energy dispersion X-ray spectroscopy (EDS). DSC study reveals that with the increase in MgF2 content the glass transition temperature (T-g) and first crystallization peak temperature (T-p(I)) decreased whilst the second crystallization peak temperature (T-p(II)) slightly increased. The CTE of the glasses is found to be in the ranges 634-6.40 x 10(-6) K-1 (50-400 degrees C). The activation energy (E-c) and frequency factor (v) both increase with increasing MgF2 content. The three-dimensional crystal growth is observed. The mica crystals are identified as fluorophlogopite, the predominant crystal phase for all the three glass specimens heat treated at 1050 degrees C. Vickers hardness values decrease with increasing amount of fluorine content and it gives better machinability. (C) 2015 Elsevier B.V. All rights reserved.

  • 158.
    Munkacsi, Noemi
    et al.
    Budapest University of Technology and Economics, Hungary.
    Mahapatra, Krushna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Communication and Household Adoption of Heating Products in Hungary2019In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, no 2, p. 1-22, article id 305Article in journal (Refereed)
    Abstract [en]

    Existing studies of heating products have analyzed the adoption of energy-efficient heating technologies from diverse micro and macroeconomic aspects, such as diffusion of innovation, willingness to pay, business models, energy pricing, etc., but the analysis from a marketing management approach based on end customer insight is still lacking. Understanding the decision-making process of end customers, and the influence of social environment at the diverse stages of the purchase process leads to a focused market strategy, thereby contributes toward overcoming the multi-level segmentation challenge faced by the manufacturers of heating products. In this context, a two-step exploratory research was conducted in December 2013 with end customers of the residential heat market in Hungary. The end customers were found to be active decision-makers engaged in deliberate planning in the purchase of heating products. They start searching for information by turning mainly to online information sources and they actively integrate their social network in all stages of the decision-making process, which means that the role of the installer is relatively less influential along the whole purchasing process. Identified influencing communication channels at the diverse stages of the purchase process may support manufacturers to develop a user-centric marketing strategy by optimizing the communication instruments in their marketing mix by, for instance, including direct end customer communication via online channels and by de-emphasizing offline communication channels.

  • 159.
    Munkacsi, Noemi
    et al.
    Budapest University of Technology and Economics, Hungary.
    Mahapatra, Krushna
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    The role of social influence in the end customer purchasing decisions on the heat market2017In: Proceedings from eceee Summer Studies, European Council for an Energy Efficient Economy (ECEEE), 2017Conference paper (Refereed)
    Abstract [en]

    The aim of this paper is to examine the role of social influence on the end customer behaviour in the purchase of heating products in residential segment. The study is based on interviews and questionnaire survey of homeowners in Hungary in 2013. Respondents are open to learn about diverse innovative heating technologies, energy types and diverse heating fuels irrespective of any purchase intention. They plan their purchase based on deliberate considerations rather than facing an emergency heating appliance breakdown. Furthermore, influence of the social environment prevails at the diverse stages of the purchase process. End customers actively conduct social search (family, friends, neighbours, colleagues, other customers with purchase experience over the Internet, etc.) besides the influencing role of the installer.

  • 160.
    Möncke, Doris
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, Greece.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Wójcik, Natalia A.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Gdańsk University of Technology, Poland.
    Palles, Damitris
    National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, Greece.
    Kamitsos, Efstratios
    National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, Greece.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    IR and Raman study of oxy-nitride glasses2018In: Presented at Glass and the Meeting of Minds  (SGT18), Cambridge, UK (2nd -5th September 2018), 2018, p. 54-Conference paper (Refereed)
  • 161.
    Möncke, Doris
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Fed Univ Sao Carlos UFSCar, Brazil;Natl Hellen Res Fdn, Greece.
    Jiusti, Jeanini
    Fed Univ Sao Carlos UFSCar, Brazil.
    Silva, Lais Dantas
    Fed Univ Sao Carlos UFSCar, Brazil.
    Martins Rodrigues, Ana Candida
    Fed Univ Sao Carlos UFSCar, Brazil.
    Long-term stability of laser-induced defects in (fluoride-)phosphate glasses doped with W, Mo, Ta, Nb and Zr ions2018In: Journal of Non-Crystalline Solids, ISSN 0022-3093, E-ISSN 1873-4812, Vol. 498, p. 401-414Article in journal (Refereed)
    Abstract [en]

    Laser-induced defects in glasses are of considerable interest for many applications from optics to photonics. The importance of low-level impurities of polyvalent ions in aiding defect formation has been identified early on. (Fluoride-)phosphate glasses are used today as laser materials, waveguides, amplifiers and luminescing materials, all sensitive to a change of the materials transmission by the interaction with light during application. To better understand the processes of defect generation and recovery, a systematic comparison of defect formation in various glasses and for various radiation sources and dopants has been conducted over the last decades. Here we will focus on (fluoride-) phosphate glasses doped with 50 to 5000 ppm of the 4d and 5d ions Zr, Nb, Ta, Mo and W. Glasses were melted under air or under reducing conditions in order to shift the redox equilibrium of the dopants before irradiation with either the 193 nm or 248 nm excimer laser. Only for W, Mo and Nb reduced ion species were confirmed by optical and/or ESR spectroscopy in the pre-irradiated glasses. However, irradiation showed for all metaphosphates the presence of reduced dopant species (W5+, Mo5+, Ta4+, Nb4+, Zr3+), acting as extrinsic hole centers (HC) after being photo-oxidized by laser irradiation to the fully oxidized d ions (Mn+)(+)-HC. Only for Ta5+ with its (Ta5+)(-)-electron center (EC), photo-reduction to the tetravalent ion was observed. Defect recovery was followed up to 16 years after the irradiation experiments, showing that most (Mn+)(+)-HC were very stable, while intrinsic HC either recombined with EC or converted into extrinsic (Mn+)(+)-HC. Due to ubiquitous iron impurities, even these high purity glasses with iron levels of 5-10 ppm or less, showed the formation of (Fe2+)(+)-HC.

  • 162.
    Nazar, Ibrahim
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Julia, Lundkvist
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Småskalig elproduktion med ORC-teknik på värmeverk i Bräkne-Hoby2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Energikontor Sydost har startat demonstrationsprojekt inom småskalig kraftvärme. Ronneby Miljö och Teknik AB driver en demonstrationsanläggning för småskalig elproduktion med ORC-turbin på värmeverk i Bräkne-Hoby. I samband med installation av ORC-turbin gjordes även ombyggnation av fjärrvärmeledning till närliggande sågverk. Detta examensarbete är en teknisk- och lönsamhetsanalys för utvärdering av investeringen. Elverkningsgrad uppgick för denna fjärrvärmesäsong till 2,23 %, alfa-värde till 2,3 %, systemverkningsgrad för ORC-system till 99,54 %. Ledningsförluster minskade från 19,7 till 17,25 % efter ombyggnation. Det visades även att sänkning av fjärrvärmereturtemperatur ökar elproduktionen. Investeringskalkyl visade en icke lönsam investering om el säljs externt. Att producera och använda el internt inom anläggningen visade sig lönsamt även utan investeringsstöd. Ombyggnation av fjärrvärmeledning visades även vara lönsamt. Tekniken är vid anslutning till värmeverk förnybar, lokal och har hög tillgänglighet vid högbelastningstider.

  • 163.
    Nygren, Astrid
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Slättengren, Robin
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Analys och jämförelse av två pilotanläggningar med olika sammansättning av membran: Vid rening av processvatten från industri2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vattentillgången på Öland har under en lång tid varit mycket ansträngd och har kommit till en punkt då det inte längre är hållbart. För att nå en mer långsiktig lösning planerar Mörbylånga kommun med hjälp av Norconsult att bygga ett vattenreningsverk. Detta kommer att rena bräckt vatten ifrån Kalmarsund samt processvatten ifrån Guldfågeln AB, som tillsammans kommer att fungera som ett komplement till det redan befintliga sötvattnet.

    Två pilotanläggningar som renar processvatten ifrån en industri, genom ultrafilter kombinerat med omvänd osmos, har utvärderats. En metod för att sammanställa de kostsamma driftparametrarna elförbrukning, förbrukning av kemikalier samt underhållsarbete vid drift och membranens inköpskostnad genom en LCC har tagits fram. Denna metod ger en ungefärlig totalkostnad per kubikmeter av det renade vattnet. Även vattenkvaliteten på ingående råvatten, vattnet mellan membranen samt det utgående vattnet har analyserats. Detta för att undersöka att processerna fungerar som den ska, samt ge en indikation på vilka mineraler som kommer att behöva tillsättas i efterhand.

    Pilot B blir ca fem kronor dyrare per kubikmeter jämfört med Pilot A. De totala kostnaderna, 9.70 – 10.79 kr/m3 för Pilot A och 15.19 – 15.28 kr/m3 för Pilot B, kan jämföras med den nuvarande kostnaden för en kubikmeter vatten i Mörbylånga, 15 kr/m3, samt den kostnad kommunen betalade sommaren 2016 för att frakta vatten i tankbilar, 70 kr/m3.

  • 164.
    Nørregård, Øyvind
    et al.
    inst. för kemiteknik, LTH, Lund, Sverige.
    Hulteberg, Christian
    inst. för kemiteknik, LTH, Lund Sverige.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Leveau, Andreas
    Hulteberg Ch&E, Tygelsjö, Sverige.
    Catalyst choise and considerations in the conversion of Glucose to glycerol.2016In: Proceedings of the 17th Nordic Symposium on Catalysis: Book of Abstracts / [ed] Ingemar Odenbrand, Christian Hulteberg, 2016, p. 204-206Conference paper (Refereed)
    Abstract [en]

    Through the 20th century the use of glycerine has mainly been focused to the food industry, the cosmetic industry and the pharmaceutical industry. The required volumes for these industries can’t be compared with the larger bulk chemicals produced today. These low requirements together with the increased glycerine production, associated with the biodiesel production from which glycerine is a large by-product, has forced the prices down to approximately 100-150 $/tonne. This low cost crude glycerine has been an initiator for developing methods on how to convert the glycerine to more usable products. A proposed method by the company Biofuel Solutions has been to convert the glycerine into bio-LPG. With the EU directives stating that at least 10 % of the fuels in the transport sector should come from renewable sources this route may turn out favourable. This will though cause a large increase in demand as one of the few new ways to provide bio-LPG and thus increase in price, which will require new ways to produce glycerine.

    With a possible increased demand on glycerine a proposed route to produce glycerine is via catalytic hydrogenation of glucose to sorbitol and further catalytic hydrogenolysis of sorbitol to glycerine. The production of sorbitol from glucose is today already industrialised with large producers such as Roquette Frères, Cargill and SPI Polyols. The industrial process is historically made batch wise with low cost Raney-nickel catalyst but with the development of good selectivity catalysts with no leaching problems it is assumed that todays’ production is mainly operating with catalyst with noble metals as the active metal, such as ruthenium, in a continuous process. For the hydrogenolysis of sorbitol to glycerine a good method is rather unexplored as the hydrogenolysis is previously mostly performed with either ethylene glycol (EG) or propylene glycol (PG) as the wanted product [1]. In context with the text above it is of great interest to investigate the catalytic hydrogenolysis of sorbitol to glycerine for the further production of bio-LPG.

    Research made on catalytic hydrogenolysis of sorbitol is done with mostly glycols as the main products, [1]. With the still reasonable selectivity of glycerine, up to 40 % with Raney-nickel as catalyst [2], the proposed research method is similar [1-3]. The planned method performed by Biofuel-Solutions includes trials in an autoclave reactor with the catalyst dispersed in the reactant solution under hydrogen pressure of 20-100 bar and mild temperatures, 100-300 °C, and stirring in resemblance to previous research [4]. As leaching issues has been seen with Raney-nickel in the hydrogenation of glucose to produce sorbitol [5], a similar process, this behaviour is expected to require certain measures which also will be tested. Tests will also include to investigate the influence of the catalyst basicity, which seems to affect the selectivity towards glycerol positively [1,2,5].

    A final process of producing bio-LPG with the start from glucose is seen in Figure 1 below. In the picture a long chain of processes-steps is displayed. In the blue box the degradation of the lignocellulosic material takes place. This is then led to the fraction where glucose is required from enzymatic hydrolysis. In the grey box to the right the glycerol conversion to LPG is shown, a multi process-step of which most details are already known within the company. 

  • 165.
    Odenbrand, Ingemar
    et al.
    Lund University.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Deactivation of SCR catalysts used in municipal waste incineration applications2016In: Proceeding of the 17th Nordic Symposium on Catalysis: Book of Abstracts / [ed] Ingemar Odenbrand, Christian Hulteberg, Lund University , 2016, p. 108-109Conference paper (Refereed)
  • 166.
    Ohlsson, Lars-Ola
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Karlsson, Sebastian
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Framtidens substrat?: En tvåstegsprocess för rötning av alger och vass i pilotskala2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta arbete är en delstudie i projektet

    Seafarm. Syftet med denna studie är att utreda om algen Laminaria Digitata och vassen Phragmites Australis är lämpliga substrat i en samrötningsprocess för biogasproduktion. Metoden som användes är experimentell och utfördes under 35 dagar med en tvåstegsreaktor bestående av en lakbädd och en UASB-reaktor. Under försökets gång upptäcktes vissa fel och brister hos apparatuppställningen vilka orsakade läckage och andra brister. Detta resulterade i ett systemförslag med skiss till en ny lakbädd samt optimering av driftparametrar om försöket ska återupprepas.

    Efter 35 dagar avslutades försöket och utifrån den data som sammanställts uppvisar processen en bra metanpotential på 589 liter CH

    4/kg COD. Processen uppvisade en låg alkalinitet med ett sjunkande pH som till följd av inmatning. Detta var grunden för den låga belastningen som processen klarade av. För framtida försök för just dessa substrat så rekommenderas en tillförsel av buffert så att alkaliniteten ökar och även möjligheterna för en högre belastning.

  • 167.
    Pardalis, Georgios
    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.
    Bravo, Giangiacomo
    Linnaeus University, Faculty of Social Sciences, Department of Social Studies.
    Mainali, Brijesh
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Swedish House Owners’ Intentions Towards Renovations: Is there a Market for One-Stop-Shop?2019In: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 9, no 7, p. 1-16, article id 164Article in journal (Refereed)
    Abstract [en]

    In this paper, we examine factors aecting owners’ intention for renovation of their detached houses. Furthermore, we analyze their interest in choosing a one-stop-shop (OSS) service for the renovation, even though such a concept is not yet established in Sweden, but emerging in other parts of Europe. Our study is based on responses to an online questionnaire survey of 971 house owners residing in Kronoberg Region in Sweden. About 76% of the respondents intend to renovate in the near future, with approximately 71% of them preferring to renovate individual components of their dwelling and 5% to renovate their whole house in steps. House owners of younger age, higher income, higher education, and those with an interest for environmental issues, were the ones most interested in physical renovations, which improves energy efficiency of the building. For those house owners, one-stop-shop can facilitate the decision-making process, and help them to choose those measures that will improve their quality of life. Approximately 20% of the respondents had a positive view towards an one-stop-shop, which is an indicator that market for such a service exists. Parameters such as quality of work, cost and energy savings and specification of measures to be adopted are the key for the promotion of one-stop-shop. Additionally, house owners want to have a certain level of involvement in the selection of actors performing the renovation. Moreover, financial incentives, e.g., loans, do not play a significant role for the selection of one-stop-shop, but act as complementary motive for house owners.

  • 168.
    Pardalis, Georgios
    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.
    Mainali, Brijesh
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Swedish construction MSEs: simply renovators or renovation service innovators?2019In: Building Research & Information, ISSN 0961-3218, E-ISSN 1466-4321, Vol. 48, no 1, p. 67-83Article in journal (Refereed)
    Abstract [en]

    To address the renovation needs of detached house stock in Sweden, micro and small-sized enterprises (MSEs), a subgroup of small and medium-sized enterprises, are expected to introduce more comprehensive house renovation solutions. One-stop-shop (OSS) is an innovative Product-Service System model that can enable MSEs to offer comprehensive renovation packages instead of existing fragmented solutions. We have applied a conceptual framework for innovation adoption in organizations and conducted an interview of 21 construction MSEs in three different geographical areas in Sweden to examine their perceptions and preparedness to adopt the OSS business concept. Findings showed that the examined MSEs are positive towards OSS as it could address the needs for the comprehensive renovation of detached houses. However, presently, are not prepared to take the coordinator’s role in such a concept mainly due to the perceived business risks, the lack of flexibility to organizational restructuring, and lack of resources and management competency to coordinate multiple tasks and actors. Those organizations lacked awareness of existing policy support and access to funding mechanisms to try new business models. As a solution, they proposed an external coordinator to be the provider of OSS, on the trial phase, whose role and characteristics need to be further examined.

  • 169.
    Pardalis, Georgios
    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.
    Mainali, Brijesh
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Jalilzadehazhari, Elaheh
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Renovation of detached houses in Sweden: Can one-stop-shop provide a solution?2019In: Presented at: International Conference on Sustainability in Energy and Buildings SEB-19, 2019, article id seb19s-006Conference paper (Refereed)
    Abstract [en]

    Based on an online survey, this paper analyzes the attitude of house owners in Sweden towards future renovations and one-stop-shop (OSS) services for deep renovation of detached houses. With the aid of a house owners’ decision-making journey for renovation, personal and contextual variables have been analyzed to identify those house owners having renovation plans in the near future, what they are going to renovate, and which needs led them to that decision. Furthermore, we examine if there is an interest in OSS concept. Results suggest that deep renovation is not yet prioritized. The priority for house owners is to change specific components of their dwelling and follow a step-wise approach. Aesthetic renovations are high on the agenda, with some structural and energy-related renovations following them. House owners between 29- 49 years of age could be the customer segment to target for deep renovations. The OSS concept seems interesting to a number of house owners, who can form an early adopters segment that could develop the market. There is a need for a cost-efficient OSS concept for deep renovations, ensuring the quality of work, and the optimization of financial products and tax incentives to accelerate the deep renovation market.

  • 170.
    Pardalis, Georgios
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Mainali, Brijesh
    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.
    One-stop-shop as an innovation, and construction SMEs: a Swedish perspective2019In: Innovative Solutions for Energy Transitions: Proceedings of the 10th International Conference on Applied Energy (ICAE2018) / [ed] Prof. J.Yanab, Prof. H.Yangc, Dr. H.Lid, Dr. X.Chene, Elsevier, 2019, Vol. 158, p. 2737-2743Conference paper (Refereed)
    Abstract [en]

    This paper examines the views of construction SMEs in Sweden regarding innovations, in particular the one-stop-shop business concept,and its adoption for renovation of detached house. The investigation is based on interviews with 10 construction SMEs and by applying aconceptual framework for organizational innovation adoption. The results suggest that, even though the one-stop-shop businessconcept is perceived as a means for growth, at present, construction SMEs in Sweden are unlikely to adopt it at present. This lackof interest is mostly related to the perceived complexity of this model and the underlying risks and uncertainties. That complexity isseen as a preventing factor as it puts at stake their current business. The interviewees proposed that there should be an entrepreneur to coordinate the actors involved in the renovation process, whose role can be further studied.

  • 171.
    Pardalis, Georgios
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Mainali, Brijesh
    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.
    One-stop-shop as an innovation, and preparedness to adopt it: A study on house renovation stakeholders in Sweden2018Conference paper (Other academic)
    Abstract [en]

    This study examines the views of stakeholders involved in house renovations regarding the one-stop-shopbusiness concept innovation, and assesses their level of preparedness to adopt such a concept in order toenter the promising market of detached house renovations. The investigation is based on 25 interviews withconstruction SMEs owners, real estate agents and loan consultants, and on a conceptual framework fororganizational innovation adoption. The results suggest that for the nonce, none of the examined stakeholdersis likely to adopt a one-stop-shop business model to enter the market of detached house renovations, eventhough this concept is seen as one with great potential. This mostly happens due to their individualcharacteristics, the complexity of one-stop-shop model related to their way of doing business and theuncertainties deriving from the adoption of such a model. Furthermore, the participation of an entrepreneur isproposed, who would coordinate all the different actors involved in the renovation process, and whose rolecan be further examined.

  • 172.
    Parsland, Charlotte
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Study of the activity of catalysts for the production of high quality biomass gasification gas: with emphasis on Ni-substituted Ba-hexaaluminates2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The fossil hydrocarbons are not inexhaustible, and their use is not without impact in our need of energy, fuels and hydrocarbons as building blocks for organic materials. The quest for renewable, environmentally more friendly technologies are in need and woody biomass is a promising candidate, well provided in the boreal parts of the world. To convert the constituents of wood into valuable gaseous products, suitable for the end use required, we need a reliable gasification technology. But to become an industrial application on full scale there are still a few issues to take into account since the presence of contaminants in the process gas will pose several issues, both technical and operational, for instance by corrosion, fouling and catalyst deactivation. Furthermore the downstream applications may have very stringent needs for syngas cleanliness depending on its use. Therefore, the levels of contaminants must be decreased by gas cleanup to fulfil the requirements of the downstream applications.

    One of the most prominent problems in biomass gasification is the formation of tars – an organic byproduct in the degradation of larger hydrocarbons. So, tar degrading catalysts are needed in order to avoid tar related operational problems such as fouling but also reduced conversion efficiency. Deactivation of catalysts is generally inevitable, but the process may be slowed or even prevented. Catalysts are often very sensitive to poisonous compounds in the process gas, but also to the harsh conditions in the gasifier, risking problems as coke formation and attrition. Alongside with having to be resistant to any physical and chemical damage, the catalyst also needs to have high selectivity and conversion rate, which would result in a more or less tar-free gas. Commercial tar reforming catalysts of today often contain nickel as the active element, but also often display a moderate to rapid deactivation due to the causes mentioned.

  • 173.
    Parsland, Charlotte
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Benito, Patricia
    University of Bologna, Italy.
    Hoang Ho, Phuoc
    University of Bologna, Italy.
    Fornasari, Guiseppe
    University of Bologna, Italy.
    Ni-substituted Ba-hexaaluminate as a new catalytic material in steam reforming of tars2017In: Europacat: 13th European Conference on Catalysis, 27-31 August 2017, Florence Italy, 2017Conference paper (Refereed)
  • 174.
    Parsland, Charlotte
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ho, Phuoc Hoang
    Univ Bologna, Italy.
    Benito, Patricia
    Univ Bologna, Italy.
    Larsson, Ann-Charlotte
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Fornasari, Giuseppe
    Univ Bologna, Italy.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ba-Ni-Hexaaluminate as a New Catalyst in the Steam Reforming of 1-Methyl Naphthalene and Methane Long-Term Studies on Sulphur Deactivation and Coke Formation2019In: Catalysis Letters, ISSN 1011-372X, E-ISSN 1572-879XArticle in journal (Refereed)
    Abstract [en]

    This work investigates the long-term performance of Ba-Ni-hexaaluminate, BaNixAl12-xO19 as a catalyst in reforming of 1-methyl naphthalene and/or methane in a model-gas simulating that from a circulating fluidized bed (CFB) gasifier during 23-29 h in a lab scale set-up, as well as the tendency for coke formation, sintering and sulphur poisoning. 1-Methyl naphthalene is used as a tar model substance. The Ba-Ni-hexaaluminate induces a high conversion of both compounds in the temperatures investigated (850 and 950 degrees C) under sulphur-free conditions. In sulphur-containing gas, the methane conversion stops at 20 ppm H2S and the reforming of 1-MNP at 850 degrees C is slightly reduced at 100 ppm.

  • 175.
    Parsland, Charlotte
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Larsson, Ann-Charlotte
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Benito, Patricia
    University of Bologna, Italy.
    Fornasari, Guiseppe
    University of Bologna, Italy.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Nickel-substituted bariumhexaaluminates as novel catalysts in steam reforming of tars2015In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 140, p. 1-11Article in journal (Refereed)
    Abstract [en]

    This work investigates the performance of Ba–Ni-hexaaluminate, BaNixAl12 − xO19, as a new catalyst in thesteam-reforming of tars. Substituted hexaaluminates are synthesized and characterized. Steam reforming testsare carried out with both a model-substance (1-methylnaphthalene) and a slip-stream from a circulatingfluidized bed gasifier. The water–gas-shift activity is studied in a lab-scale set-up. Barium–nickel substitutedhexaaluminates show a high catalytic activity for tar cracking, and also shows activity for water–gas-shift.

  • 176.
    Parsland, Charlotte
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Larsson, Ann-Charlotte
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ni-substituted Ba-hexaaluminates catalyst for tar reforming from gasified iomass2016In: Proceedings of the 17th Nordic Symposium on Catalysis: Book of Abstracts / [ed] Ingemar Odenbrand, Christian Hulteberg, 2016, p. 256-257Conference paper (Refereed)
  • 177.
    Pechsiri, Joseph S
    et al.
    Royal Institute of Technology.
    Thomas, Jean-Baptiste
    Royal Institute of Technology.
    Risén, Emma
    Royal Institute of Technology ; Sweco Environment AB.
    Ribeiro, Maurico S
    Royal Institute of Technology.
    Malmström, Maria E
    Royal Institute of Technology.
    Nylund, Göran
    University of Gothenburg.
    Jansson, Anette
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Paiva, Henrik
    University of Gothenburg.
    Gröndahl, Fredrik
    Royal Institute of Technology.
    Energy performance and greenhouse gas emissions of kelp cultivation for biogas and fertilizer recovery in Sweden2016In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 573, p. 347-355Article in journal (Refereed)
    Abstract [en]

    The cultivation of seaweed as a feedstock for third generation biofuels is gathering interest in Europe, however, many questions remain unanswered in practise, notably regarding scales of operation, energy returns on investment (EROI) and greenhouse gas (GHG) emissions, all of which are crucial to determine commercial viability. This study performed an energy and GHG emissions analysis, using EROI and GHG savings potential respectively, as indicators of commercial viability for two systems: the Swedish Seafarm project's seaweed cultivation (0.5 ha), biogas and fertilizer biorefinery, and an estimation of the same system scaled up and adjusted to a cultivation of 10 ha. Based on a conservative estimate of biogas yield, neither the 0.5 ha case nor the up-scaled 10 ha estimates met the (commercial viability) target EROI of 3, nor the European Union Renewable Energy Directive GHG savings target of 60% for biofuels, however the potential for commercial viability was substantially improved by scaling up operations: GHG emissions and energy demand, per unit of biogas, was almost halved by scaling operations up by a factor of twenty, thereby approaching the EROI and GHG savings targets set, under beneficial biogas production conditions. Further analysis identified processes whose optimisations would have a large impact on energy use and emissions (such as anaerobic digestion) as well as others embodying potential for further economies of scale (such as harvesting), both of which would be of interest for future developments of kelp to biogas and fertilizer biorefineries.

  • 178.
    Pettersson, Jens
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Andersson, Sven
    Babcock & Wilcox Volund AB, Sweden;Chalmers University Technol, Sweden.
    Bäfver, Linda
    SP Sveriges Tekniska Forskningsinstitut, Sweden.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Investigation of the Collection Efficiency of a Wet Electrostatic Precipitator at a Municipal Solid Waste-Fueled Combined Heat and Power Plant Using Various Measuring Methods2019In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 33, no 6, p. 5282-5292Article in journal (Refereed)
    Abstract [en]

    This article reports results from measurements of mainly submicrometer particles at the inlet and outlet of a newly designed industrial wet electrostatic precipitator (WESP) in a combined heat and power plant fueled with municipal solid waste. The measurements were carried out with dual electric low-pressure impactors in parallel at the precipitator inlet and outlet. In addition, measurements were carried out with traditional total dust filters, low-pressure impactors, a scanning mobility particle sizer, and an aerodynamic particle sizer. The measurements aimed to characterize the aerosol particles and measure the efficiency of the WESP with special attention to fine and ultrafine particles. In general, the WESP performance and response to varying conditions was found to be in line with predictions made for the design. The WESP featured a cooled collector surface, but based on the limited results, no conclusion could be drawn regarding any possible improvement from collector cooling. The characterization of the aerosol particulate matter was challenging because of fast fluctuations in particle concentration. Methodological considerations are pointed out, mainly regarding the SMPS and ELPI measuring systems.

  • 179.
    Piccardo, Chiara
    et al.
    University of Genoa, Italy.
    Dodoo, Ambrose
    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.
    Comparative Life-Cycle Analysis of Building Materials for the Thermal Upgrade of an Existing Building2019In: SBE19 Brussels - BAMB-CIRCPATH "Buildings as Material Banks - A Pathway For A Circular Future"5–7 February 2019, Brussels, Belgium, Institute of Physics Publishing (IOPP), 2019, Vol. 225, article id 012044Conference paper (Refereed)
    Abstract [en]

    The existing building stock is estimated to need major renovations in the near future. At the same time, the EU energy-efficiency strategy entails upgrading the energy performance of renovated buildings to meet the nearly-zero energy standard. To upgrade existing buildings, two main groups of measures can be adopted: thermally-improved building envelope and energy-efficient technical devices. The first measure usually involves additional building materials for thermal insulation and new building cladding, as well as new windows and doors. A number of commercially-available materials can be used to renovate thermal building envelopes. This study compares the life-cycle primary energy use and CO2 emission when renovating an existing building using different materials, commonly used in renovated buildings. A Swedish building constructed in 1972 is used as a case-study building. The building's envelope is assumed to be renovated to meet the Swedish passive house standard. The entire life cycle of the building envelope renovation is taken into account. The results show that the selection of building materials can significantly reduce the production primary energy and associated CO2 emissions by up to 62% and 77%, respectively. The results suggest that a careful material choice can significantly contribute to reduce primary energy use and CO2 emissions associated with energy renovation of buildings, especially when renewable-based materials are used.

  • 180.
    Piccardo, Chiara
    et al.
    University of Genoa, Italy.
    Dodoo, Ambrose
    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.
    Energy and carbon balance of materials used in a building envelope renovation2019In: SBE19 Brussels - BAMB-CIRCPATH "Buildings as Material Banks - A Pathway For A Circular Future"5–7 February 2019, Brussels, Belgium, Institute of Physics Publishing (IOPP), 2019, Vol. 225, article id 012045Conference paper (Refereed)
    Abstract [en]

    Construction and demolition waste (CDW) are a priority waste stream in EU's polices, accounting for about 30% of all waste generated. At the same time, according to the EU energy-efficiency directive, existing buildings subject to significant renovation need to be upgraded in their thermal building envelope in order to meet higher energy performance standard. This involves additional building materials and hence increases the CDW generation. This study investigates the energy and CO2 emission balance of building envelope renovation when using different building materials, taking into account the production and end-of-life stages. The study is based on a Swedish case-study building assumed to be upgraded to the passive house standard. Benefits from waste recovering are considered, including construction and demolition wastes. The results show that the selection of building materials can significantly affect the primary energy and CO2 emission balances. Depending on the material alternative the end-of-life primary energy use and net CO2 emission can be reduced by 5%-21% and 2%-24%, respectively, compared to the initial primary energy use and net CO2 emission. Therefore, a careful material choice at the design stage, as well as an efficient waste management, can contribute to reduce primary energy use and CO2 emission associated with energy renovation of existing buildings.

  • 181.
    Razmjoo, Narges
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Characterization of conversion zones in a reciprocating grate furnace firing wet woody biomass2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Grate-firing systems are a common and popular combustion technology for burning biomass. However, combustion of biomass in these furnaces may emit a large amount of pollutants in the form of CO, CH4, PAH, NOx, and particles. These furnaces need to be further developed to increase their efficiency and improve the overall system performance while ensuring environmental compatibility. To improve the combustion of biomass in grate furnaces, it is vital to understand the processes occurring inside both the fuel bed and the gas phase above the bed (freeboard).

    The aim of this study was to characterize the conversion zones in two reciprocating-grate furnaces, with 4 and 12 MW maximum thermal outputs, firing wet woody biomass, mainly by measuring the temperature and gas concentration distributions. Measurements in the freeboard were conducted in both of the furnaces. However, measurements in the fuel bed were carried out only in the 4-MW furnace, in which the influence of two parameters, i.e., the fuel moisture and the primary airflow rate, on the bed conversion was investigated. Furthermore, a simplified model of the drying of wet biomass on a grate was developed and used to estimate the drying rate and to simulate the extent of the drying zone along the grate. The model was then validated against measurements of the fuel moisture and flue gas water vapor concentration made by NIR and FTIR, respectively.

    Measurements of temperature and gas concentration (i.e., CO, CO2, O2, CH4, and NO) profiles in the fuel bed were carried out through ports located in the wall of the furnace, by means of a stainless steel probe incorporating a K-type thermocouple. The temperature distribution along the height of the fuel bed was measured through a view-glass port, using a bent probe. High temperatures within a layer of about 0.1 m from the grate surface indicated the existence of a combustion layer at the bottom of the fuel bed (co-current combustion pattern). The drying rate of the moist fuel was calculated by the model to be about 0.0211–0.0235 kg water/m2s, under a certain condition. Therefore, the drying layer of the moist fuel was estimated to occupy almost two-thirds of the total grate length.

    Measurements of temperature and gas concentration profiles in the freeboard of the two furnaces were carried out by means of a water-cooled stainless-steel suction pyrometer. The pyrometer was introduced into the furnaces through the measuring ports, located along the pathways of the hot gas flow, and positioned at several locations between the wall and the furnace width center. For both of the furnaces, the temperature varied mainly in the 600–1000°C range in the primary combustion chamber, and reached about 1100–1200°C in the secondary chamber. A significant rise in NO concentration was observed in the transition sections between the primary and secondary combustion chambers of the furnaces. There was a positive correlation between NO and O2 at the ports in the secondary combustion chambers, which implied that in this high temperature region, the O2 concentration was the limiting factor for oxidation of N-volatiles to NO.

  • 182.
    Razmjoo, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Hermansson, Sven
    RISE, Sweden;Södra Innovation, Sweden.
    Morgalla, Mario
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Study of the transient release of water vapor from a fuel bed of wet biomass in a reciprocating-grate furnace2019In: Journal of the Energy Institute, ISSN 1743-9671, Vol. 92, no 4, p. 843-854Article in journal (Refereed)
    Abstract [en]

    The present study investigates how sudden changes in fuel moisture affected the combustion characteristics of the fuel bed in a 4-MW reciprocating-grate furnace. The moisture content of the fuel fed to the furnace was monitored online using a near-infrared spectroscopy device, and the water vapor concentration in the flue gas was measured continuously. To obtain experimental data on fuel-bed conditions, the temperature and gas composition in the bed were measured using a probe. A simplified drying model was developed using the measured gas composition values as inputs. The model was then used to estimate the drying rate and to simulate the extent of the drying zone along the grate. Measurements indicated that a change in the moisture content of the fuel fed to the furnace was detected as a change in water vapor concentration in the flue gas with a delay of about 2 h. The model predicted that a portion of wet fuel would need about 2 h to become dry, in line with the measured time delay of the water vapor concentration change in the flue gas. Overall, there was good alignment between the measured and simulated results, supporting the validity of the model and the assumed mechanisms.

  • 183.
    Razmjoo, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Hermansson, Sven
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Characterization of the fuel bed combustion of wood residues in a 4 MW grate boiler2015In: European Biomass Conference and Exhibition Proceedings, 2015, p. 741-744Conference paper (Refereed)
    Abstract [en]

    Information about distributions of temperature and gas species within the fuel bed is of great importance in studying the formation of pollutants in an industrial-scale biomass boiler. The main objective of this study was to investigate the gas composition and temperature in some available sections of the fuel bed of a 4 MW reciprocating grate boiler, burning mixture of fresh pine wood chips, bark, and sawdust with two significantly different moisture content levels. The averageCO, CO2,CH4, and O2 concentrations measured during the combustion of the more moist fuel (about 60 mass %) were about 12, 12, 2, and 4 vol. %, respectively, whereas the corresponding values for the less moist fuel (about 45 mass %) were about15, 10, 2.5, and 5 vol. %, respectively. Higher concentration of CO and lower concentration of CO2 for the less moist fuel could originate either from the char conversion process or from the reactions of the devolatilizationgas products.

  • 184.
    Razmjoo, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Sefidari, Hamid
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Experimental investigation of fuel bed combustion in an industrial grate boiler2015Conference paper (Refereed)
    Abstract [en]

    Information about distributions of temperature and gas species within the fuel bed is of great importance in studying the formation of pollutants in an industrial-scale biomass boiler. The main objective of this study was to investigate the gas composition and temperature in some available sections of the fuel bed of a 4 MW reciprocating grate boiler. The results showed that the temperature profiles of the grate bars and the fuel bed suggest significant temperature gradients versus the height of the fuel bed. The averaged NO, CO, CO2, and O2 concentrations measured in the fuel bed were about 80 ppm, 21, 11 and 1 vol. %, respectively.

  • 185.
    Razmjoo, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Sefidari, Hamid
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Luleå University of Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Measurements of temperature and gas composition within the burning bed of wet woody residues in a 4 MW moving grate boiler2016In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 152, p. 438-445Article in journal (Refereed)
    Abstract [en]

    Moving grate firing systems are widely used for biomass combustion. The characteristics of the fuel bed combustion in moving grate boilers are of practical interest as they are directly related to the release of pollutants and affect the furnace efficiency. Measurements of temperature and gas species concentrations inside the fuel bed are necessary to improve our understanding of the highly complex processes involved in biomass combustion.There have been few experimental studies of the fuel bed of industrial scale grate furnaces. The present study measured temperature and gas species concentrations within a thick burning bed of wet woody biomass, in a  4 MW reciprocating grate boiler. Measurements were carried out under three different operating conditions through ports located in the wall of the furnace using a stainless steel probe incorporating a thermocouple. Temperatures of about 1000 °C were measured close to the grate, indicating intense combustion at the bottom of the fuel bed. The temperature distribution along the bed height showed that different stages of the combustion process take place in horizontally adjacent layers along the grate. Higher flow rates of the primary air resulted in relatively higher CO and lower CO2 and NO concentrations in the fuel bed.

  • 186.
    Razmjoo, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    In-bed combustion charachteristics of wet wood chips and sawdust in a full-scale grate boiler2017In: Proceedings 13th International Conference on Energy for a Clean Environment, 2017Conference paper (Refereed)
  • 187.
    Razmjoo, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Investigation of moist fuel bed combustion in grate furnaces2017In: Proceedings of Nordic Flame Days, 10-11 October, 2017, Stockholm, 2017Conference paper (Refereed)
  • 188.
    Rupar-Gadd, Katarina
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Parametric Study of Self-heating properties in Woody Biomass Samples2016In: EUBCE 2016 – 24th European Biomass Conference & Exhibition: 6th Jun, 2016 - 9th Jun, 2016, Amsterdam, The Netherlands, ETA-Florence Renewable Energy , 2016, p. 578-579Conference paper (Refereed)
    Abstract [en]

    The current investigation focused on obtaining experimental results on self-heating properties of different woody biomasses during lab-scale storage. The heat released from the different biomass samples was measured by isothermal calorimetry, with the purpose to assess the contribution to self-heating during storage. Biomass samples were stored at different temperatures and metals were added in order to investigate if the presence of metals would increase the risk of self-heating. There was an increase in heat release after 10-30 days of storage, and the addition of metals gave rise to an increase in heat release. The results are intended to be useful when planning for the large-scale use of different biomasses, leading to the need of storage.

  • 189.
    Rupar-Gadd, Katarina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Forss, Jörgen
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Self-heating properties of softwood samples investigated by using isothermal calorimetry2018In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 111, p. 206-212Article in journal (Refereed)
    Abstract [en]

    The investigation focused on obtaining experimental results from the self-heating properties of different softwood samples during lab-scale storage. The samples investigated were a mixture of dried soft wood sawdust, softwood pellets 8 mm in diameter, and aged softwood sawdust stored outdoors for three months. Isothermal calorimetry was used to measure the heat released from the biomass samples and assess the contribution to self-heating during storage. Softwood samples were stored at 20 °C, 50 °C, 55 °C and 60 °C, and the metals manganese, copper and iron were added as a water solution to investigate if the presence of metals would increase the risk of self-heating. For most sample series, the highest levels of heat release were found after approximately 10 days of storage; sample series stored at 50 °C displayed the highest levels. The addition of copper resulted in levels of heat release 135% higher than samples without metal added.

  • 190.
    Rupar-Gadd, Katarina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Wiman, Bo
    Ibrahim, Muhammad Asim
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Laohaprapanon, Sawanya
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Hogland, William
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    A theoretical and experimental framework for the study of vegetation as a screen against aerosol pollution2014Report (Other academic)
    Abstract [en]

    It is well known that vegetation acts a sink for aerosol particles, with the particle-capture efficiency strongly related to vegetation characteristics (such as dimensions of needles and leaves) and to  particle size and aerodynamic conditions. However, there is a need for studies of ways to harness this sink capacity for constructing “green screens” to help reduce aerosol-particle concentrations, and thus health effects, in downwind residential areas. In this report we present a simplified mathematical model for the particle-capture processes involved and use results of model simulations to explore ways to address the problem through experiments with vegetation-filter components (“green filter packs”) placed in a windtunnel. Because of the exploratory nature of our work, the very limited logistics available, and the severe time constraints for the work (a few weeks only were available) the report is shaped as a kind of “scientific narrative” (rather than as a traditional technical paper). A series of tests is described wherein steps are taken towards practical implementation of experimental designs and procedures  based on a simple smoke-aerosol generator and measurements of smoke concentrations upwind and downwind of “green filter packs”. Measurements involve laser-based particle counters, two-stage Nuclepore filter systems, and Solid Phase Microextraction (SPME) techniques followed by Gas Chromatography-Mass Spectrometry. The main objective of the work was thus to illustrate ways to design experiments – rather than perform full-fledged experimental work – and to show how experimental data can be processed and used to assist in the study of vegetation as “pollution screens”. Despite the very limited time available for the work, the results show that our experimental approach is able to generate relevant information; for instance, a study of the particle-filtration capacity of a “green filter pack” consisting of an arrangement with Scots pine needles yielded interesting data.  Also, the  study suggests opportunities for more systematic comparisons between theory and practice, inasmuch it showed how, in principle, parameters involved in the mathematical model can be quantified. The SPME tests also provided interesting information with respect to chemical characteristics of the smoke-aerosol that was generated for the experiments. However, the tests with Nuclepore-filter sampling as well as the SPME applications showed needs for improving the smoke-generation method so that high and stable smoke-aerosol concentrations can be maintained over long periods (several hours).

     

     

    Our observations and findings imply that several refinements to the experimental design will be needed, including with  respect to methods for assessing the distribution of particle number and mass as a function of particle size (in the present study, the distribution is indicated by two particle-size classes only, 0.5 to 5 μm and >5 μm). Several other needs for improving the modelling as well experimental approach are also discussed in the report. Finally, a few observations on the needs for field-based studies are made together with remarks on the implications of the multi-disciplinary nature of this kind of work, with is linkages to the broader air-pollution context.

  • 191.
    Rupar-Gadd, Katarina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Zethraeus, Björn
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Safety and logistic aspects on biomass as RES2014Report (Other (popular science, discussion, etc.))
    Abstract [en]

    The use of solid biomass is already dominant among RES not only in the South Baltic but in the European Federation as a whole and is expected to grow. With this, not only emissions from combustion but also emissions from storage and handling are apt to increase.The storage and handling of biomass is, however, not free from risks and problems.The current report discusses some of the risks associated with the large-scale handling and storage of biomass with special emphasis on the processes occurring during storage and the mechanisms behind auto-ignition.The report contains experimental results and information on different biomasses and their characteristics, with focus on the characteristics affecting the storage and handling properties. It is intended to be useful when planning for the use of different biomasses, leading to the need of storage.

  • 192.
    Rupar-Gadd, Katarina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Zethraeus, Björn
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Safety, Self-Ignition and Storage: Investigation of Woody and Oily Biomass Samples2015In: 23rd European Biomass Conference and Exhibition, Vienna, Austria, 1-4 June 2015, ETA-Florence Renewable Energies , 2015, Vol. 23, p. 642-645Conference paper (Refereed)
    Abstract [en]

    The current investigation focused on obtaining experimental results on properties of different woody and oily biomasses during lab-scale storage. During large-scale storage of vegetable oils, biodiesel and woody biomasses, physical, biological and chemical processes lead to deterioration of the fuel, self-heating and in some cases to self-ignition. The heat released from the different biomass samples was measured by isothermal calorimetry, with the purpose to assess the biomass suitability for storage. The highest thermal output came from the boiled linseed oil, but also from olive oil. Wood pellets give rise to different levels of thermal output during storage and the levels depend on the moisture content, ambient gas media but not the resin content. The total energy release, as well as the peak value for the thermal power development in the individual ampoules, was limited by the amount of oxygen present. In spite of this, chemical heat release rates well exceeding 50 W/tonne were registered already at a sample temperature of 50 °C. The results are intended to be useful when planning for the large-scale use of different biomasses, leading to the need of storage. By measuring the heat released from different biomass samples, the biomass suitability for storage can be assessed. 

  • 193.
    Samuelsson, Stina
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Denitrifikationsmöjligheter hos lakvattnet på Bredemads avfallsdeponi i Ljungby2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I examensarbetet har möjlig denitrifikationshastighet för lakvattnet på Bredemads avfallsdeponi i Ljungby undersökts. Denitrifikationshastigheten har tagits fram i satsvisa och kontinuerliga försök där Reppos 40T och Brenntaplus VP1 har jämförts som externa kolkällor. De satsvisa försöken har genomförts i temperaturerna 15 °C, 20 °C och 22,5 °C och de kontinuerliga försöken har genomförts med reningsmetoden ”Moving Bed Biofilm Reactor” (MBBR) med bärare som hade en skyddad yta på 500 m2/m3.

    Denitrifikationshastigheten i g/(dygn•m2) med Reppos 40T var 0,45 och med Brenntaplus VP1 1,05. I reaktorn med Reppos 40T var fyllnadsgraden 48 % och denitrifikationshastigheten 4,5 g/(h•m3). I reaktorn med Brenntaplus VP1 var fyllnadsgraden 41 % och denitrifikationshastigheten 9,1 g/(h•m3). 

  • 194.
    Santos, Graziely Cristina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Univ. Estadual Paulista, Brazil.
    Forss, Jörgen
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Corso, Carlos Renato
    Univ. Estadual Paulista, Brazil.
    Redox mediator evaluation in the azo dye biodegradation2015Conference paper (Refereed)
    Abstract [en]

    Azo dye degradation occurs by means of the oxidation–reduction reactions which have the azo dye acting as final electron acceptor. Some carbon sources can act as electron donors because the products of their metabolism act as redox mediators. In order to enhance the dye biodegradation process, the present study aims to evaluate the decolorization of an artificial wastewater, containing the azo dye Direct Red 75 (DR75), led by a microbial consortium from rice husks, testing the effect in the process of glucose and yeast extract as carbon sources. Samples with and without 0.1 M Sodium phosphate buffer were also analysed. The decolorization was measured by means UV-VIS spectrophotometry. The percentage of decolorization of the samples over the time indicates that the sample with yeast extract, rinse water of rice husks and without buffer presented the best decolorization rate, about 80%. Therefore, the results presented in this study may also suggest that yeast extract is a better carbon source for dye biodegradation than glucose.

  • 195.
    Santos-Pereira, Graziely Cristina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Corso, Carlos Renato
    UNESP - São Paulo State University, Brazil.
    Forss, Jörgen
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Evaluation of two different carriers in the biodegradation process of an azo dye2019In: Journal of Environmental Science and Health. Part A: Toxic/Hazardous Substances and Environmental Engineering, ISSN 1093-4529, E-ISSN 1532-4117, p. 1-11Article in journal (Refereed)
    Abstract [en]

    Purpose The MBBR solution has been applied for the textile wastewater treatment. However, in order to develop cost-effectivesolutions, waste biomass can be used as carrier. Rice husks are agricultural waste which have been used as an adsorbent of dyes;besides, they can provide and sustain suitable microorganism communities for the degradation of dyes. This study aimed toevaluate the biodegradation of the azo dye Direct Red 75 in two treatment systems with different carriers.Methods Bioreactor Awas composed by an anaerobic bioreactor filled with Kaldnes K1 carriers employed in the MBBR technologyand the study was performed in 2 different temperatures, 30 ± 0.5 °C and 21 ± 2 °C. Biofilter B was composed by a sequencedanaerobic-aerobic system with rice husks as carriers and this study was performed at 21 ± 2 °C. The rice husks was also employed asa source of microorganisms in both systems. Decolourization, surface area of the carriers and other parameters were analysed.Results Biofilter B showed high rates of decolorization, mainly over 90% in all HRT tested (24, 48 and 12 h), presenting itself asa stable system, whereas Bioreactors A showed better performances with 48 h of HRT, about 85%for A at 30 ± 0.5 °C and 45%at21 ± 2 °C. With a similar amount of carriers, analyses showed that rice husks had a much larger surface for microorganisms togrow on than Kaldnes K1.Conclusion The Biofilter B is a worthwhile system to be investigated and applied for the decolourization of textile wastewatertreatment; for instance, in developing countries.

  • 196.
    Sathre, Roger
    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.
    Climate effects of electricity production fuelled by coal, forest slash and municipal solid waste with and without carbon capture2017In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 122, p. 711-723Article in journal (Refereed)
    Abstract [en]

    We analyse the climate implications of producing electricity in large-scale conversion plants using coal, forest slash and municipal solid waste with and without carbon capture and storage (CCS). We calculate the primary energy, carbon dioxide (CO2) and methane (CH4) emission profiles, and the cumulative radiative forcing (CRF) of different systems that produce the same amount of electricity. We find that using slash or waste for electricity production instead of coal somewhat increases the instantaneous CO2 emission from the power plant, but avoids significant subsequent emissions from decaying slash in forests or waste in landfills. For slash used instead of coal, we find robust near- and long-term reductions in total emissions and CRF. Climate effects of using waste instead of coal are more ambiguous: CRF is reduced when CCS is used, but without CCS there is little or no climate benefits of using waste directly for energy, assuming that landfill gas is recovered and used for electricity production. The application of CCS requires more fuel, but strongly reduces the CO2 emissions. The use of slash or waste together with CCS results in negative net emissions and CRF, i.e. global cooling.

  • 197.
    Sefidari, Hamid
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Razmjoo, Narges
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    An experimental study of combustion and emissions of two types of woody biomass in a 12-MW reciprocating-grate boiler2014In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 135, p. 120-129Article in journal (Refereed)
    Abstract [en]

    The gaseous emissions of primary concern from biomass combustion are nitrogen oxides (NOX), carbon monoxide, and various unburned gaseous components. Detailed characterization of the gas in the hot reaction zones is necessary to study the release, formation, and evolution of the gas components. In the present study, gas temperature and concentration were measured in a 12-MWth biomass-fired reciprocating-grate boiler operated with over-fire air and flue-gas recirculation. Temperature measurement was combined with flue gas quenching and sample gas extraction using two water-cooled stainless-steel suction pyrometers. The concentration profiles of O2, NO, and CO were experimentally determined throughout the furnace, and the profile gas temperature was measured in several positions inside the furnace for the two types of woody biomass studied. For both fuels, the gas temperature varied between approximately 450 °C (average primary chamber temperature) and 1200 °C (average secondary chamber temperature). The concentration profiles of CO and O2 suggested no conclusive difference between the two types of biomass. However, the local mean concentrations of NO and NOX emission factors (measured in the stack) were higher for Greenery fuel due to its higher nitrogen content than that of Standard fuel.

  • 198.
    Shahbandian, Maryam
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Building Renovation and Property Value2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The concern of climate change and Greenhouse Gas emission have increased national consideration toward energy efficiency. Despite noticeable action which have taken by EU cities and Sweden government to mitigate the climate change, there is still shortage in appropriate energy measurements in old residential buildings. Due to the fact that a large share of residential buildings in Sweden have constructed more than 40 years ago, most of them need energy renovation  to enhance efficiency and saving more energy. In order to encourage home owners toward energy efficiency renovations, some cost effective measurements have to introduce to people with the view of effect on property value.  To this end, 50 detached houses and villas in Kronoberg County in Sweden have been chosen and analyzed to identify how renovation can increase the property value. These houses have been set in different categories by location, heating system, deep renovation, energy and aesthetic renovation. After that, compares the sold prices and biding prices for each category. Moreover, it analyses the people behavior toward renovation to see how can motive people to adopt necessary energy efficient renovation. This research also shows the current situation of building renovation, the most favourite renovation which are adopted by people as well as providing information about the factors affect the value of the house after renovation.

  • 199.
    Sylveson, David
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Uppföljningsanalys av en biogasanläggning: Sammanställning av driftdata från More Biogas Smålands AB2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Driftdata från More Biogas anläggning i Kalmar har sammanställts och analyserats för att föreslå förbättringar i sammansättningen av den inkommande substratmixen för att öka gasproduktionen. C/N kvoten för den inkommande substratmixen är låg då en optimal C/N kvot är mellan 20 till 30. För att få upp den totala C/N kvoten till 15 behövs 27 ton halm i månaden tillsättas och 80 ton för att få upp den till 20. Det är även bra att tillsätta halm från ströbädd eller hönsgödsel som har en hög TS-halt eftersom det finns möjlighet till en ökad VS-belastning i processen.Slakteriavfall gav en positiv effekt på gasproduktionen och efter en jämförselse av två tidsperioder gav resultatet att gasproduktionen ökade med en MWh per ton TS av tillsatt slakteriavfall.Det finns inget tecken på att processen är hämmad av de inhiberande parametrarna eftersom inte gasproduktionen minskade de månader då de inhiberande parametrarna var högre.

  • 200.
    Tandiyoputri, Gadis
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    The effect of thermal pre-treatment and waste paper addition to biomethane potential of macro algae Saccharina lattissima2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As a steady renewable energy technology, biogas is a viable alternative to reduce our dependency to fossil fuels and to prevent severe climate change. Biogas potential can be improved through combining different types of substrate and inoculum, as well as through substrate pre-treatments. This study aims to observe and explore the potential of macroalgae Saccharina latissima as a promising new source in renewable energy technology. The biomethane potential of macroalgae in mixture with additional substrate of mixed waste paper will be studied as a mean to improve the biogas yield. It will also compare the biomethane results of the macroalgae and the mixed substrate (macroalgae plus waste paper) exposure to non-thermal and thermal pre-treatment.

    In the experiment, the ratio of 3 : 1 for gr VS inoculum : gr VS substrate is used in a quantitative BMP test up to 25 days of incubation. The substrate was pre-treated mechanically (blended) into slurry and thermally through pre-heating at high temperature (130°C, 45 minutes) before digested by the inoculum. In the end of incubation period at STP (0°C and 1 atm), the highest cumulative methane yield of 260.91 Nml CH4/gr VS substrate was achieved by sample in Var – I, while the control has cumulative methane yield of 50.52 Nml CH4/gr VS. Thermally pre-treated samples resulted in lower BMP yields than the ones which were not thermally pre-treated. Through the ANOVA t-test of the methane volume and biomethane potential (BMP) yields, it is concluded that the thermal pre-treatment and waste paper addition only give little effect to biomethane production from macroalgae.

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