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  • 1.
    Biollaz, S.
    et al.
    PSI.
    Calbry-Muzyka, A.
    PSI.
    Rodriguez, S.
    PSI.
    Sárossy, Z.
    DTU.
    Ravenni, G.
    DTU.
    Fateev, A.
    DTU.
    Seiser, R.
    UCSD.
    Eberhard, M.
    KIT.
    Kolb, T.
    KIT.
    Heikkinen, N.
    VTT.
    Reinikainen, M.
    VTT.
    Brown, R.C.
    Iowa State University, USA.
    Johnston, P.A.
    Iowa State University, USA.
    Nau, P.
    DLR.
    Geigle, K.P.
    DLR.
    Kutne, P.
    DLR.
    Işık-Gülsaç, I.
    TÜBİTAK Mam.
    Aksoy, P.
    TÜBİTAK Mam.
    Çetin, Y.
    TÜBİTAK Mam.
    Sarıoğlan, A.
    TÜBİTAK Mam.
    Tsekos, C.
    Delft University of Technology, The Netherlands.
    de Jong, W.
    Delft University of Technology, The Netherlands.
    Benedikt, F.
    TU Wien, Austria.
    Hofbauer, H.
    TU Wien, Austria.
    Waldheim, L.
    SFC.
    Engvall, K.
    Royal Institute of Technology.
    Neubauer, Y.
    Technical University of Berlin, Germany.
    Funcia, I.
    CENER.
    Gil, J.
    CENER.
    del Campo, I.
    CENER.
    Wilson, I.
    University of Glasgow, UK.
    Khan, Z.
    University of Glasgow, UK.
    Gall, D.
    Gothenburg University.
    Gómez-Barea, A.
    University of Seville, Spain.
    Schmidt, F.
    Umeå University.
    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.
    Anca-Couce, A.
    Graz University of Technology, Austria.
    von Berg, L.
    Graz University of Technology, Austria.
    Larsson, A.
    GoBiGas.
    Sánchez Hervás, J.M.
    CIEMAT.
    van Egmond, B.F.
    ECN part of TNO.
    Geusebroek, M.
    ECN part of TNO.
    Toonen, A.
    ECN part of TNO.
    Kuipers, J.
    ECN part of TNO.
    Cieplik, M.
    ECN part of TNO.
    Boymans, E.H.
    ECN part of TNO.
    Grootjes, A.J.
    ECN part of TNO.
    Fischer, F.
    TUM.
    Schmid, M.
    University of Stuttgart, Germany.
    Maric, J.
    Chalmers University of Technology.
    Defoort, F.
    CEA.
    Ravel, S.
    CEA.
    Thiery, S.
    CEA.
    Balland, M.
    CEA.
    Kienzl, N.
    Bioenergy 2020+.
    Martini, S.
    Bioenergy 2020+.
    Loipersböck, J.
    Bioenergy 2020+.
    Basset, E.
    ENGIE Lab CRIGEN.
    Barba, A.
    ENGIE Lab CRIGEN.
    Willeboer, W.
    RWE-Essent.
    Venderbosch, R.
    BTG.
    Carpenter, D.
    NREL.
    Pinto, F.
    LNEG.
    Barisano, D.
    ENEA.
    Baratieri, M.
    UNIBZ.
    Ballesteros, R.
    UCLM.
    Mourao Vilela, C. (Editor)
    ECN part of TNO.
    Vreugdenhil, B.J. (Editor)
    ECN part of TNO.
    Gas analysis in gasification of biomass and waste: Guideline report: Document 12018Report (Refereed)
    Abstract [en]

    Gasification is generally acknowledged as one of the technologies that will enable the large-scale production of biofuels and chemicals from biomass and waste. One of the main technical challenges associated to the deployment of biomass gasification as a commercial technology is the cleaning and upgrading of the product gas. The contaminants of product gas from biomass/waste gasification include dust, tars, alkali metals, BTX, sulphur-, nitrogen- and chlorine compounds, and heavy metals. Proper measurement of the components and contaminants of the product gas is essential for the monitoring of gasification-based plants (efficiency, product quality, by-products), as well as for the proper design of the downstream gas cleaning train (for example, scrubbers, sorbents, etc.). In practice, a trade-off between reliability, accuracy and cost has to be reached when selecting the proper analysis technique for a specific application. The deployment and implementation of inexpensive yet accurate gas analysis techniques to monitor the fate of gas contaminants might play an important role in the commercialization of biomass and waste gasification processes.

    This special report commissioned by the IEA Bioenergy Task 33 group compiles a representative part of the extensive work developed in the last years by relevant actors in the field of gas analysis applied to(biomass and waste) gasification. The approach of this report has been based on the creation of a team of contributing partners who have supplied material to the report. This networking approach has been complemented with a literature review. The report is composed of a set of 2 documents. Document 1(the present report) describes the available analysis techniques (both commercial and underdevelopment) for the measurement of different compounds of interest present in gasification gas. The objective is to help the reader to properly select the analysis technique most suitable to the target compounds and the intended application. Document 1 also describes some examples of application of gas analysis at commercial-, pilot- and research gasification plants, as well as examples of recent and current joint research activities in the field. The information contained in Document 1 is complemented with a book of factsheets on gas analysis techniques in Document 2, and a collection of video blogs which illustrate some of the analysis techniques described in Documents 1 and 2.

    This guideline report would like to become a platform for the reinforcement of the network of partners working on the development and application of gas analysis, thus fostering collaboration and exchange of knowledge. As such, this report should become a living document which incorporates in future coming progress and developments in the field.

  • 2.
    Biollaz, S.
    et al.
    PSI.
    Calbry-Muzyka, A.
    PSI.
    Rodriguez, S.
    PSI.
    Sárossy, Z.
    DTU.
    Ravenni, G.
    DTU.
    Fateev, A.
    DTU.
    Seiser, R.
    UCSD.
    Eberhard, M.
    KIT.
    Kolb, T.
    KIT.
    Heikkinen, N.
    VTT.
    Reinikainen, M.
    VTT.
    Brown, R.C.
    Iowa State University, USA.
    Johnston, P.A.
    Iowa State University, USA.
    Nau, P.
    DLR.
    Geigle, K.P.
    DLR.
    Kutne, P.
    DLR.
    Işık-Gülsaç, I.
    TÜBİTAK Mam.
    Aksoy, P.
    TÜBİTAK Mam.
    Çetin, Y.
    TÜBİTAK Mam.
    Sarıoğlan, A.
    TÜBİTAK Mam.
    Tsekos, C.
    Delft University of Technology, The Netherlands.
    de Jong, W.
    Delft University of Technology, The Netherlands.
    Benedikt, F.
    TU Wien, Austria.
    Hofbauer, H.
    TU Wien, Austria.
    Waldheim, L.
    SFC.
    Engvall, K.
    Royal Institute of Technology.
    Neubauer, Y.
    Technical University of Berlin, Germany.
    Funcia, I.
    CENER.
    Gil, J.
    CENER.
    del Campo, I.
    CENER.
    Wilson, I.
    University of Glasgow, UK.
    Khan, Z.
    University of Glasgow, UK.
    Gall, D.
    Gothenburg University.
    Gómez-Barea, A.
    University of Seville, Spain.
    Schmidt, F.
    Umeå University.
    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.
    Anca-Couce, A.
    Graz University of Technology, Austria.
    von Berg, L.
    Graz University of Technology, Austria.
    Larsson, A.
    GoBiGas.
    Sánchez Hervás, J.M.
    CIEMAT.
    van Egmond, B.F.
    ECN part of TNO.
    Geusebroek, M.
    ECN part of TNO.
    Toonen, A.
    ECN part of TNO.
    Kuipers, J.
    ECN part of TNO.
    Cieplik, M.
    ECN part of TNO.
    Boymans, E.H.
    ECN part of TNO.
    Grootjes, A.J.
    ECN part of TNO.
    Fischer, F.
    TUM.
    Schmid, M.
    University of Stuttgart, Germany.
    Maric, J.
    Chalmers University of Technology.
    Defoort, F.
    CEA.
    Ravel, S.
    CEA.
    Thiery, S.
    CEA.
    Balland, M.
    CEA.
    Kienzl, N.
    Bioenergy 2020+.
    Martini, S.
    Bioenergy 2020+.
    Loipersböck, J.
    Bioenergy 2020+.
    Basset, E.
    ENGIE Lab CRIGEN.
    Barba, A.
    ENGIE Lab CRIGEN.
    Willeboer, W.
    RWE-Essent.
    Venderbosch, R.
    BTG.
    Carpenter, D.
    NREL.
    Pinto, F.
    LNEG.
    Barisano, D.
    ENEA.
    Baratieri, M.
    UNIBZ.
    Ballesteros, R.
    UCLM.
    Mourao Vilela, C. (Editor)
    ECN part of TNO.
    Vreugdenhil, B.J. (Editor)
    ECN part of TNO.
    Gas analysis in gasification of biomass and waste: Guideline report: Document 2 - Factsheets on gas analysis techniques2018Report (Refereed)
    Abstract [en]

    Gasification is generally acknowledged as one of the technologies that will enable the large-scale production of biofuels and chemicals from biomass and waste. One of the main technical challenges associated to the deployment of biomass gasification as a commercial technology is the cleaning and upgrading of the product gas. The contaminants of product gas from biomass/waste gasification include dust, tars, alkali metals, BTX, sulphur-, nitrogen- and chlorine compounds, and heavy metals. Proper measurement of the components and contaminants of the product gas is essential for the monitoring of gasification-based plants (efficiency, product quality, by-products), as well as for the proper design of the downstream gas cleaning train (for example, scrubbers, sorbents, etc.). The deployment and implementation of inexpensive yet accurate gas analysis techniques to monitor the fate of gas contaminants might play an important role in the commercialization of biomass and waste gasification processes.

    This special report commissioned by the IEA Bioenergy Task 33 group compiles a representative part of the extensive work developed in the last years by relevant actors in the field of gas analysis applied to (biomass and waste) gasification. The approach of this report has been based on the creation of a team of contributing partners who have supplied material to the report. This networking approach has been complemented with a literature review. This guideline report would like to become a platform for the reinforcement of the network of partners working on the development and application of gas analysis, thus fostering collaboration and exchange of knowledge. As such, this report should become a living document which incorporates in future coming progress and developments in the field.

  • 3.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Usage of Biofuels in Sweden2013In: CSR-2 Catalyst for renewable sources: Fuel, Energy, Chemicals Book of Abstracts / [ed] Vadim Yakovlev, Boreskov Institute of Catalysis, Novosibrisk, Russia: Boreskov Institute of Catalysis , 2013, p. 5-7Conference paper (Refereed)
    Abstract [en]

    In Sweden, biofuels have come into substantial use, in an extent that are claimed to be bigger than use of fossil oil. One driving force for this have been the CO2-tax that was introduced in 1991 (1). According to SVEBIO:s calculations (2) based on the Swedish Energy Agency´s prognosis, the total energy consumption in Sweden 2012 was 404 TWh. If the figure is broken down on the different energy sources (figure 1) one can see that the consumption roughly distribute in three different, equally sized, blocks, Biofuels, fossil fuels and water & nuclear power. The major use of the fossil fuels is for transport and the water & nuclear power is used as electric power. The main use of the biofuels is for heating in the industrial sector and as district heating. In 2009 the consumption from those two segments was 85 TWh, and 10 TWh of bio power was co-produced giving an average biomass to electricity efficiency of 12%. This indicates a substantial conversion potential from hot water production to combined heat and power (CHP) production. in Sweden 2013 broken down on the different energy sources. In 2006 the pulp, paper and sawmill industry accounted for 95% of the bio energy consumption in the industrial sector, and the major biofuel consumed was black liquor (5). However, the pulp and paper industries also produced the black liquor in their own processes. The major energy source (58%) for district heating during 2006 was woody biomass (chips, pellets etc.) followed by waste (24%), peat (6%) and others (12%) (5). The use of peat has probably decreased since 2006 since peat is no longer regarded as a renewable energy source. While the use of biofuel for heating purpose is well developed and the bio-power is expected to grow, the use in the transport sector is small, 9 TWh or 7% in 2011. The main consumption there is due to the mandatory addition (5%) of ethanol to gasoline and FAME to diesel (6). The Swedish authorities have announced plans to increase the renewable content to 7.5 % in 2015 on the way to fulfill the EU’s goal of 10 % renewable transportation fuels in 2020. However the new proposed fuel directive in EU says that a maximum of 5% renewable fuel may be produced from food sources like sugars and vegetable oils. Another bothersome fact is that, in principle, all rape seed oil produced in Sweden is consumed (95-97%) in the food sector, and consequently all FAME used (in principle) in Sweden is imported as FAME, rape seed oil or seed (6). In Sweden a new source of biodiesel have emerged, tall oil diesel. Tall oil is extracted from black liquor and refined into a diesel fraction (not FAME) and can be mixed into fossil diesel, i.e. Preem Evolution diesel. The SUNPINE plant in Piteå have a capacity of 100 000 metric tons of tall oil diesel per annum, while the total potential in all of Sweden is claimed to be 200 000 tons (7). 100 000 tons of tall oil corresponds to 1% of the total diesel consumption in Sweden. in Sweden for 2010 and a prognosis for 2014. (6). Accordingly, the profoundest task is to decrease the fossil fuel dependency in the transport sector, and clearly, the first generation biofuels can´t do this on its own. Biogas is a fuel gas with high methane content that can be used in a similar way to natural gas; for instance for cooking, heating and as transportation fuel. Today biogas is produced by fermentation of waste (municipal waste, sludge, manure), but can be produced by gasification of biomass, for instance from forest residues such as branches and rots (GROT in Swedish). To get high efficiency in the production, the lower hydrocarbons, mainly methane, in the producer gas, should not be converted into synthesis gas. Instead a synthesis gas with high methane content is sought. This limits the drainage of chemically bonded energy, due to the exothermic reaction in the synthesis step (so called methanisation). In 2011 0.7 TWh of biogas was produced in Sweden by fermentation of waste (6) and there were no production by gasification, at least not of economic importance. The potential seems to be large, though. In 2008 the total potential for biogas production, in Sweden, from waste by fermentation and gasification was estimated to 70 TWh (10 TWh fermentation and 60 TWh gasification) (8). This figure includes only different types of waste and no dedicated agricultural crops or dedicated forest harvest. Activities in the biogas sector, by gasification, in Sweden are the Göteborgs energi´s Gobigas project in Gothenburg and Eon´s Bio2G-project, now pending, in south of Sweden. If the producer gas is cleaned and upgraded into synthesis gas also other fuels could be produced. In Sweden methanol and DME productions are planned for in the Värmlands metanol-project and at Chemrecs DME production plant in Piteå.

  • 4.
    Brandin, Jan
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Hulteberg, Christian
    Lunds Tekniska Högskola .
    Leveau, Andreas
    Biofuel-Solutions AB.
    Selective Catalysts for Glycerol Dehydration2013In: CRS-2, Catalysis for Renewable Sources: Fuel,Energy,ChemicalsBook of Abstracts / [ed] Vadim Yakovlev, Boreskov Institute of Catalysis, Novosibirsk, Russia: Boreskov Institute of Catalysis , 2013, p. 17-18Conference paper (Refereed)
    Abstract [en]

     There has been an increased interest over the last decade for replacing fossil based feedstock’s with renewable ones. There are several such feedstock’s that are currently being investigated such as cellulose, lignin, hemicellulose, triglycerides etc. However, when trying to perform selective reactions an as homogeneous feedstock as possible is preferable. One such feedstock example is glycerol, a side-product from biofuels production, which is a tri-alcohol and thus has much flexibility for reactions, e.g. dehydration, hydrogenation, addition reactions etc. Glycerol in itself is a good starting point for fine chemicals production being non-toxic and available in rather large quantities [1-2]. A key reaction for glycerol valorisation is the dehydration of glycerol to form acrolein, an unsaturated C3 aldehyde, which may be used for producing acrylic acid, acrylonitrile and other important chemcial products. It has recently been shown that pore-condensation of glycerol is an issue under industrial like conditions, leading to liquid-phase reactions and speeding up the catalyst activity and selectivity loss [3]. To address this issue, modified catalyst materials have been prepared where the relevant micro and meso pores have been removed by thermal sintering; calculations have shown that pores below 45 Å may be subject to pore condensation. The catalyst starting material was a 10% WO3 by weight supported on ZrO2 in the form of beads 1–2 mm and it was thermally treated at 400°C, 500°C, 600°C, 700°C, 700°C, 800°C, 850°C, 900°C and 1000°C for 2 hours. The catalysts were characterised using nitrogen adsorption, mercury intrusion porosimetry (MIP), Raman spectroscopy and ammonia temperature programmed desorption. The thermal sintered catalysts show first of all a decreasing BET surface area with sintering commencing between 700°C and 800°C when it decreases from the initial 71 m2/g to 62 m2/g and at 1000°C there is a mere 5 m2/g of surface area left. During sintering, the micro and meso-porosity is reduced as evidenced by MIP and depicted in figure 1. As may be seen in the figure, sintering decrease the amount of pores below and around 100 Å is reduced at a sintering temperature of 800°C and above. The most suitable catalyst based on the MIP appears to be the one sintered at 850°C which is further strengthened by the Raman analysis. There is a clear shift in the tungsten structure from monoclinic to triclinic between 850°C and 900°C and it is believed that the monoclinic phase is important for activity and selectivity. Further, the heat treatment shows that there is an increase in catalyst acidity measured as mmol NH3/(m2/g) but a decrease in the acid strength as evidenced by a decrease in the desorption peak maximum temperature.

     

  • 5.
    Brandin, Jan
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Odenbrand, Ingemar
    Lund University .
    Poisoning of SCR Catalysts used in Municipal Waste Incineration Applications2017In: Topics in catalysis, ISSN 1022-5528, E-ISSN 1572-9028, Vol. 60, no 17-18, p. 1306-1316Article in journal (Refereed)
    Abstract [en]

    A commercial vanadia, tungsta on titania SCRcatalyst was poisoned in a side stream in a waste incinerationplant. The effect of especially alkali metal poisoningwas observed resulting in a decreased activity at long timesof exposure. The deactivation after 2311 h was 36% whilethe decrease in surface area was only 7.6%. Thus the majorcause for deactivation was a chemical blocking of acidicsites by alkali metals. The activation–deactivation modelshowed excellent agreement with experimental data. Themodel suggests that the original adsorption sites, fromthe preparation of the catalyst, are rapidly deactivated butare replaced by a new population of adsorption sites dueto activation of the catalyst surface by sulphur compounds(SO2, SO3)in the flue gas.

  • 6.
    Brandin, Jan
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Tunér, Martin
    Lunds Tekniska Högskola.
    Odenbrand, Ingemar
    Lunds Tekniska Högskola.
    Small Scale Gasifiction: Gas Engine CHP for Biofuels2011Report (Other academic)
    Abstract [en]

    In a joint project, Linnaeus University in Växjö (LNU) and the Faculty of Engineering at Lund University (LTH) were commissioned by the Swedish Energy Agency to make an inventory of the techniques and systems for small scale gasifier-gas engine combined heat and power (CHP) production and to evaluate the technology. Small scale is defined here as plants up to 10 MWth, and the fuel used in the gasifier is some kind of biofuel, usually woody biofuel in the form of chips, pellets, or sawdust. The study is presented in this report.

    The report has been compiled by searching the literature, participating in seminars, visiting plants, interviewing contact people, and following up contacts by e-mail and phone.

    The first, descriptive part of the report, examines the state-of-the-art technology for gasification, gas cleaning, and gas engines. The second part presents case studies of the selected plants:

    • Meva Innovation’s VIPP-VORTEX CHP plant
    • DTU’s VIKING CHP plant
    • Güssing bio-power station
    • Harboøre CHP plant
    • Skive CHP plant

    The case studies examine the features of the plants and the included unit operations, the kinds of fuels used and the net electricity and overall efficiencies obtained. The investment and operating costs are presented when available as are figures on plant availability. In addition we survey the international situation, mainly covering developing countries.

    Generally, the technology is sufficiently mature for commercialization, though some unit operations, for example catalytic tar reforming, still needs further development. Further development and optimization will probably streamline the performance of the various plants so that their biofuel-to-electricity efficiency reaches 30-40 % and overall performance efficiency in the range of 90 %.

    The Harboøre, Skive, and Güssing plant types are considered appropriate for municipal CHP systems, while the Viking and VIPP-VORTEX plants are smaller and considered appropriate for replacing hot water plants in district heating network. The Danish Technical University (DTU) Biomass Gasification Group and Meva International have identified a potentially large market in the developing countries of Asia.

    Areas for suggested further research and development include:

    • Gas      cleaning/upgrading
    • Utilization      of produced heat
    • System      integration/optimization
    • Small scale      oxygen production
    • Gas engine      developments
  • 7.
    Figueroa, Daniela
    et al.
    Umeå University ; Umeå Marine Sciences Centre.
    Rowe, O. F.
    Umeå University ; University of Helsinki, Finland.
    Paczkowska, Joanna
    Umeå University.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Andersson, Agneta
    Umeå University ; Umeå Marine Sciences Centre.
    Allochthonous Carbon-a Major Driver of Bacterioplankton Production in the Subarctic Northern Baltic Sea2016In: Microbial Ecology, ISSN 0095-3628, E-ISSN 1432-184X, Vol. 71, no 4, p. 789-801Article in journal (Refereed)
    Abstract [en]

    Heterotrophic bacteria are, in many aquatic systems, reliant on autochthonous organic carbon as their energy source. One exception is low-productive humic lakes, where allochthonous dissolved organic matter (ADOM) is the major driver. We hypothesized that bacterial production (BP) is similarly regulated in subarctic estuaries that receive large amounts of riverine material. BP and potential explanatory factors were measured during May-August 2011 in the subarctic Råne Estuary, northern Sweden. The highest BP was observed in spring, concomitant with the spring river-flush and the lowest rates occurred during summer when primary production (PP) peaked. PLS correlations showed that ∼60 % of the BP variation was explained by different ADOM components, measured as humic substances, dissolved organic carbon (DOC) and coloured dissolved organic matter (CDOM). On average, BP was threefold higher than PP. The bioavailability of allochthonous dissolved organic carbon (ADOC) exhibited large spatial and temporal variation; however, the average value was low, ∼2 %. Bioassay analysis showed that BP in the near-shore area was potentially carbon limited early in the season, while BP at seaward stations was more commonly limited by nitrogen-phosphorus. Nevertheless, the bioassay indicated that ADOC could contribute significantly to the in situ BP, ∼60 %. We conclude that ADOM is a regulator of BP in the studied estuary. Thus, projected climate-induced increases in river discharge suggest that BP will increase in subarctic coastal areas during the coming century.

  • 8.
    Gregeby, Erik
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Welander, Ulrika
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Provrötning av marina substrat i laboratorie- och pilotskala: Delstudie i projektet Biogas – Nya substrat från havet2012Report (Other academic)
    Abstract [sv]

    Denna rapport omfattar delstudie 4 av projektet Biogas-Nya substrat från havet. Inom delstudien har ett antal provrötningar av substrat från havet (vass, musslor, alger och skrapsill) genomförts. Syftet med delstudien var att få fram metanpotentialen för de olika substraten och att öka kunskapen kring hur dessa substrat uppför sig i en biogasprocess. Projektet var ett samverkansprojekt delfinansierat av EU Regionala fonden för Småland och öarna. Projektledare var Regionförbundet i Kalmar län. Inledningsvis genomfördes ett antal satsvisa försök med samtliga substrat. Metanpotentialerna för vassen, musslorna, algerna respektive skarpsillen var 400, 270, ca 210 och 460 Ndm3/kg VS. Ymp hämtades från Kalmar Biogas ABs industriella rötkammare. Vassen samrötades också med industriellt avfall i ett kontinuerligt våtrötningsförsök. Försöket genomfördes i två total omrörda tankreaktorer med volymen 30 l/st. Tillsatsen av vass gav en utökad metanproduktion med 220 Ndm3/kgVS.

    Vassen och musslorna studerades också i torrötningsförsök. Försöken i laboratorieskala genomfördes vid Avdelningen för Bioteknik i Lund medan försöket med musslor i pilotskala genomfördes vid Avdelningen för Bioenergiteknik, Linnéuniversitet. Metanpotentialen för vassen var i torrötningsförsöket ca 220 Ndm3/kg VS vilket är lika med potentialen i våtrötningsförsöket. För musslorna erhölls en metanpotential på 330 Ndm3/kg VS i laboratorieskaleförsöket. Pilotskaleförsöket visade att hydrolysen etablerades på likartat sätt som i laboratorieskaleförsöket. Metanhalten var ca 70 %. En visuell inspektion av musslorna efter rötningen visade också att endast skalen återstod. Det är dock inte möjligt att ange en metanpotential från detta försök beroende på ett antal tekniska problem med processen. Processen byggdes inför detta försök och det fanns inte tid att testköra den samma före försökets start.Arbetet med de satsvisa försöken och det kontinuerliga våtrötningsförsöket av vass genomfördes i samarbete med Kalmar Biogas AB. Detta bland annat genom att Kalmar Biogas AB tillhandahöll sin försöksanläggning med satsvisa och kontinuerliga reaktorer till projektet.

  • 9.
    Gustafsson, Eva
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Lin, Leteng
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Strand, Michael
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Characteristics of aerosol particles from steam and oxygen gasification of various biofuels2010In: 18th European Biomass Conference and Exhibition: From resarch to industry and markets, ETA Renewable Energies and WIP Renewable Energies , 2010, p. 900-902Conference paper (Refereed)
    Abstract [en]

    The present study investigated how the characteristics of the particulate matter (PM) from steam and oxygen gasification of biomass were affected by the biofuel used. The results show that the biofuel had a large impact on the fine mode PM generated during the gasification, both on the particle size distribution and on the elementary composition. When using miscanthus as fuel, high concentrations of ultrafine particles consisting of potassium chloride were formed compared to when using high- and low-quality wood (wood A and wood B) as fuels. The impact of the biofuel on the coarse mode PM was less in this study. Large amounts of bed material dominated the coarse fraction. However, heavy metals were detected in the coarse mode PM when using wood B, constituting treated wood, as fuel.

  • 10.
    Gustafsson, Eva
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Lin, Leteng
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Strand, Michael
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Characterization of particulate matter in the hot product gas from atmospheric fluidized bed biomass gasifiers2011In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 35, no Supplement 1, p. 71-78Article in journal (Refereed)
    Abstract [en]

    This study compares the characteristics of particulate matter (PM) in the hot product gas from three different atmospheric fluidized bed biomass gasifiers: a bubbling fluidized bed (BFB) gasifier, a circulating fluidized bed (CFB) gasifier, and an indirect BFB gasifier (the latter integrated with a CFB boiler). All gasifiers displayed a bimodal particle mass size distribution with a fine mode in the <0.5 μm size range and a coarse mode in the >0.5 μm size range. Compared with the mass concentration of the coarse mode the mass concentration of the fine mode was low in all gasifiers. For both the BFB and CFB gasifiers the fine-mode PM had a similar inorganic composition, indicating an origin from the ash and the magnesite bed material used in both gasifiers. In the indirect BFB gasifier the fine-mode PM was instead dominated by potassium and chlorine, and the tar fraction properties evoked tar condensation in the sampling system that affected mainly the fine-mode PM. The coarse-mode PM in the BFB gasifier was dominated by char fragments abraded from the pyrolyzed wood pellets. In the CFB gasifier the coarse-mode PM was mainly ash and magnesite bed material that passed through the process cyclone. In the indirect BFB gasifier the coarse-mode PM was mainly ash, probably originating both from the BFB gasifier and the CFB boiler.

  • 11.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Haus, Sylvia
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Ortiz, Carina
    Swedish University of Agricultural Sciences.
    Sathre, Roger
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Dynamic impacts of forest residues on primary energy use and greenhouse gas emissions2014In: The 9th Conference on Sustainable Development of Energy, Water and Environment Systems - SDEWES. September 20 - 27, 2014, Venice-Istanbul, 2014Conference paper (Refereed)
  • 12.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Bioenergy pathways for cars: Effects on primary energy use, climate change and energy system integration2016In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 115, no 3, p. 1779-1789Article in journal (Refereed)
    Abstract [en]

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

  • 13.
    Helgesson, Per Otto Ragnar
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Båberg, Gustaf Elias
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Biogasframställning på kryssningsfartyg2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Fuel is one of the biggest costs in shipping today, and new technologies are being developed to save fuel. But there is potential to make fuel today aboard cruise ships. One of the biggest expenses in making biogas on land is the heating of the substrate, this cost can be eliminated on ships by using waste heat from engines and steam systems. This report explores the possibility of producing biogas by using toilet and food waste that is created daily aboard cruise ships. What components are needed, calculations of the space they would take and how much gas could be produced. The report was conducted by examining how biogas is produced on land, what are the most common technologies used today? And if they are technically possible aboard a cruise ship? To calculate gas potential, tank and reactor volume. Data has been collected from four cruise ships. The results show that it is possible to create biogas. But that the amount of gas could not justify the cost of building a biogas plant aboard cruise ships.

  • 14.
    Hermansson, Sven
    et al.
    SP.
    Backéus, Sofia
    Bohman, Christoffer
    Gulliksson, Hans
    Larsson, Sylvia
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Öhman, Marcu
    Testbädd Mellanskalig Biorbränsleförbränning - en förstudie2014Report (Other academic)
    Abstract [en]

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

  • 15.
    Hulteberg, Christian
    et al.
    Biofuel-Solution i Malmö AB (Lund University/Chemical engineering).
    Brandin, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Engineering. Biofuel-Solution i Malmö AB.
    A Process for Producing Acrolein2012Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    Disclosed is a process for dehydrating glycerol into acrolein over an acidic catalyst in gas phase in the presence of hydrogen, minimizing side reactions forming carbon deposits on the catalyst.

  • 16.
    Hulteberg, Christian
    et al.
    Biofuel-Solution i Malmö AB ( Lund University/ Chemical Engineering) .
    Brandin, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Engineering. Biofuel-Solution i Malmö AB.
    Method for Hydrogenating 1,2-Unsaturated Carbonylic Compounds2011Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    Disclosed is a method of hydrogenating an1,2-unsaturated carbonylic compound to obtain the corresponding saturated carbonylic compound in the presence of a palladium catalyst with heterogeneous distribution of palladium

  • 17.
    Hulteberg, Christian
    et al.
    Biofuel-solution I Malmö AB (Lund University/ Chemical Engineering).
    Brandin, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Engineering. Biofuel-Solution i Malmö AB.
    Process for Preparing Lower Hydrocarbons from Glycerol2011Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The present invention relates to a process of preparing hydrocarbons from oxygenated hydrocarbons by use of at least two catalysts.

  • 18.
    Hulteberg, Christian
    et al.
    Biofuel-solution i Malmö AB (Lund University/Chemical Engineering).
    Brandin, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Engineering. Biofuel-solution i Malmö AB.
    Woods, Richard Root
    Primafuel Inc. (US).
    Porter, Brook
    Primafuel inc. (US).
    Gas Phase Process for Monoalcohol Production from Glycerol2008Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    A method of producing short chain alcohols from glycerol generated as a byproduct of biodiesel production is provided.

  • 19.
    Jansson, Anette
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Rupar-Gadd, Katarina
    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.
    Welander, Ulrika
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Pilot-Scale Experiments Using Cultivated Macro Algae for Biogas Production, Part of a Future Seafarm Biorefinery2016In: 24th EUBCE Online Proceedings 2016: Setting the course for a biobased economy. Held in Amsterdam, The Netherlands, 6 - 9 June 2016, ETA-Florence Renewable Energies , 2016, p. 627-629Conference paper (Refereed)
    Abstract [en]

    The research is focused on evaluation of substrates not commonly used for biogas production and the development and optimization of processes adjusted to these substrates. This study deals with evaluation of sea weeds (Saccharina Lattisima and Laminaria digitata). Biomethane potential tests (BMP) have shown the methane potential of the algae to be 180-440 l CH4/kg organic material. These potentials are in the same range as potentials found for commonly used substrates such as sewage sludge and slaughterhouse waste. Sampling of produced biogas, substrate and digest were performed by using Solid Phase Microextraction (SPME) followed by analysis by a Gas Chromatograph with a Mass Spectrometrer (GC-MS) in order to develop a method to be able to characterize, monitor and possibly control the process.

  • 20.
    Jiang, Junfei
    et al.
    Chinese Academy of Sciences (CAS), China.
    Lang, Lin
    Chinese Academy of Sciences (CAS), China.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Liu, Huacai
    Chinese Academy of Sciences (CAS), China.
    Yin, Xiuli
    Chinese Academy of Sciences (CAS), China.
    Wu, Chuang-zhi
    Chinese Academy of Sciences (CAS), China.
    Partial oxidation of filter cake particles from biomass gasification process in the simulated product gas environment2018In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 32, no 2, p. 1703-1710Article in journal (Refereed)
    Abstract [en]

    Filtration failure occurs when filter media is blocked by accumulated solid particles. Suitable operating conditions were investigated for cake cleaning by partial oxidation of filter-cake particles (FCP) during biomass gasification. The mechanism of the FCP partial oxidation was investigated in a ceramic filter and by using thermo-gravimetric analysis through a temperature-programmed route in a 2 vol.% O2–N2 environment. Partial oxidation of the FCP in the simulated product gas environment was examined at 300–600°C in a ceramic filter that was set and heated in a laboratory-scale fixed reactor. Four reaction stages, namely drying, pre-oxidation, complex oxidation and non-oxidation, occurred in the FCP partial oxidation when the temperature increased from 30°C to 800°C in a 2 vol.% O2–N2 environment. Partial oxidation was more effective for FCP mass loss from 275 to 725°C. Experimental results obtained in a ceramic filter indicated that the best operating temperature and FCP loading occurred at 400°C and 1.59 g/cm2, respectively. The FCP were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy and Brunaeur–Emmett–Teller before and after partial oxidation. Fourier-transform infrared spectroscopy analysis revealed that partial oxidation of the FCP can result in a significant decrease in C–Hn (alkyl and aromatic) groups and an increase in C=O (carboxylic acids) groups. The scanning electron microscopy and Brunaeur–Emmett–Teller analysis suggests that during partial oxidation, the FCP underwent pore or pit formation, expansion, amalgamation and destruction.

  • 21.
    Larsson, Martin
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Tvådimensionell vattenmodellstudie av rökgasflöde i rosterugn:  2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Rapporten beskriver resultaten av en tvådimensionell vattenmodellering av gasflödet genom en 15 MW rosterugn. Den redovisar vilken påverkan fördelningen av förbränningsluft, placering av dysor för luft och rökgasåterföring, samt eldstadsutformning har för blandningen av brännbara gaser och luft i pannans sekundärzon, och därigenom vilka effekter det har på utsläpp av kväveoxider, koloxid och partiklar.

  • 22.
    Legrand, Catherine
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Olofsson, Martin
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Growing algae in Scandinavia: utopia or opportunity?2011In: Algae: The sustainable biomass for the future.: Perspectives from the submariner project algae cooperation event Trelleborg, Sweden - September 28-29, 2011., Berlin, Germany: s.Pro sustainable projects GmbH , 2011, p. 16-17Conference paper (Other (popular science, discussion, etc.))
  • 23.
    Lin, Leteng
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Char conversion kinetics and aerosol characterization in biomass gasification2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biomass gasification is a thermochemical conversion by partial oxidation at elevated temperature of solid biomass into a gaseous energy carrier. The product gas contains the major components CO, H2, CO2, CH4, as well as some tar and inorganic impurities and solid particles such as ash, bed material, soot and char. The aim of this work is to develop an aerosol-based method to investigate on-line the reactivity of the suspended biomass char particles at high temperatures, and to apply aerosol measurement systems for sampling and characterizing particulate matter in the hot product gas from gasifiers.

    An aerosol-based method including the steps for generating, transporting, and oxidizing suspended char particles (0.5–10 µm) was proposed and developed for investigation of char reactivity at high temperatures. An aerodynamic particle sizer (APS) spectrometer was used to measure the particle size distributions. A tapered element oscillating microbalance (TEOM) was used to measure the change of mass concentrations of particles in the carrier gas, before and after conversion. The intrinsic kinetics of various biomass (wood, straw, miscanthus) char particles have been experimentally established in a wide temperature range for both combustion (in air/oxygen) and gasification (in 33 vol% CO2 or 33 vol% steam), up to 800°C and 1300°C, respectively, by combining the aerosol method with thermogravimetric analysis (TGA). The general CO2 or steam gasification reactivity of chars from different biomass could be ranked as wood > miscanthus > straw. In CO2 or steam gasification, the reactivity of char samples measured by the aerosol method at 1300°C would vary by a factor of 4-9 comparing with the extrapolated estimation from the TGA results at the low temperatures. This indicates that high-temperature reactivity estimation by extrapolation should be used with care. Variations of the morphology and the effective density of char particles during conversion indicated that in the initial stage of char conversion (either combustion or gasification), pore growth was dominant up to a certain conversion, and shrinkage or fusing would occur in the later stage. The aerosol-based method presents a set of benefits which are advantageous compared to previously established techniques: no mass transfer limitation at high temperatures; the flexibility to switch to different gas agent combined with continuous feeding of char sample; and the on-line measurement of particle mass and size. The aerosol method is not applicable under the conditions where the reaction rate is slow, since longer residence time will increase the probability of particle losses. In addition to laboratory applications, the aerosol method has potentials for on-line investigation of concentration and reactivity of suspended char fragments sampled directly from the product gas in different types of gasifiers.

    Particulate matter (10 nm–10 µm) in the product gas was characterized for the size distribution, morphology and elemental composition by both on-line and off-line techniques. An aerosol particle measurement system including a dilution probe connected in series with a packed activated carbon bed was applied to extract aerosol from the hot product gas produced in the gasifiers using wood as feedstock: an indirect bubbling fluidized bed gasifier and a circulating fluidized bed (CFB) gasifier. The fine and coarse particles from the CFB gasifier contained calcium and magnesium, indicating the contributions from the ash and the magnesite bed material. From the indirect gasifier, the fine-mode (<0.5 µm) particles were dominated by potassium and chlorine whereas the coarse-mode (>0.5 µm) particles were dominated by calcium and silicon, probably from the ash and the bed material. Char fragments were identified in the hot product gas and contribute to the coarse-mode particles in both gasifiers.

     

  • 24.
    Lin, Leteng
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Investigation of the intrinsic CO2 gasification kinetics of biomass char at medium to high temperatures2013In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 109, no SI, p. 220-228Article in journal (Refereed)
    Abstract [en]

    In total eight char samples from pelletized wood, miscanthus, and straw were prepared under various pyrolysis conditions. The CO2 gasification kinetics for each sample was established in the temperature range from 800 °C to 1300 °C by the combination of thermogravimetric analysis (TGA) and a novel aerosol-based method. The aerosol-based method was used for the high temperature range between 1100 °C and 1300 °C, by gasifying suspended char particles (0.5–10 μm) in an oxidizing carrier gas. A tapered element oscillating microbalance (TEOM) was used to measure the change of mass concentrations of particles in the carrier gas, before and after gasification. The results showed that the aerosol-based method could be used to investigate the intrinsic gasification kinetics of biomass char, at least up to 1300 °C. All char samples showed similar reactivity in the low temperature range. However, above 1000 °C there were significant differences in reactivity, and at 1300 °C the conversion of the wood was in the order of 10 times faster than that of straw. The general char reactivity order in this study was wood > miscanthus > straw.

  • 25.
    Lin, Leteng
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Strand, Michael
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Online investigation of steam gasification kinetics of biomass chars up to high temperatures2014In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 28, no 1, p. 607-613Article in journal (Refereed)
    Abstract [en]

    In this study, a novel aerosol-based method has been further developed and applied for on-line investigating of steam gasification kinetics of suspended biomass char particles. By combining the aerosol method with thermogravimetric analysis, the gasification kinetics were established in steam (33 vol%)-N2 atmosphere from 800°C to 1300°C for char samples produced from pelletized wood, straw, and miscanthus. The aerosol method includes steps for generating, suspending, and gasifying char particles. The conversion of the char particles was established by measuring the change in particle size distributions and mass concentrations using an aerodynamic particle sizer (APS) spectrometer and a tapered element oscillating microbalance (TEOM), respectively. The reactivity of three char samples could be ranked as wood > miscanthus > straw. The activation energy was 155 kJ·mol-1 for wood char, 199 kJ·mol-1 for miscanthus char, and 222 kJ·mol-1 for straw char. Results interpreted from TEOM and APS measurements indicated that the effective density of char particles initially decreased until a certain level of conversion was reached, and then remained constant. 

  • 26.
    Lin, Leteng
    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.
    Statistical model to reproduce the combustion behavior of domestic-scale wood pellets burners2016In: Proceedings of the 24th European Biomass Conference: Setting the course for a biobased economy, ETA-Florence Renewable Energies , 2016, p. 666-673Conference paper (Refereed)
    Abstract [en]

    A simplified statistical model was developed to simulate the combustion behavior in wood pellets burners based on the eddy dissipation concept and the assumption that the turbulence to some extents can be treated in a similar way in both the larger scales and the smaller scales. The combustion system was divided into several macroscopic sub-volumes which were characterized by plug flow function with axial diffusion that helps to bridge the geometry with the mixing status and describe the dissipation of turbulence by means of digital filter. Initially a time series of fuel-air mixture was defined according to feedstock and air supply in burner and then successively modified in the following sub-volumes based on the predefined function and additional air. With favor of mass and energy balance the final gas composition can be approximately distributed by water gas equilibrium. After involved the system response of gas analysis instrumentation, the modelled results were compared with experimental tests in two commercialized types of pellet burners, named gasification type and combustion type respectively. The model predicted reasonably the over-all behavior of domestic-scale pellet burners on the mean value and standard deviation of gas compositions, especially the behavior of CO2 and O2 in both cases. The CO emission was simulated unstably but within an acceptable range. This model can be used as an on-line predictor in combustion control systems and may thus serve as a tool for fast-response combustion control. 

  • 27.
    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.
    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.

  • 28.
    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.

  • 29.
    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.

  • 30.
    Olofsson, Martin
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Del Pino, Victoria
    NECTON Company, Portugal.
    Lamela, Teresa
    NECTON Company, Portugal.
    Bergé, Jean Pascal
    Ifremer Nantes, France.
    Nilsson, Emmelie
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Legrand, Catherine
    Linnaeus University, Faculty of Science and Engineering, School of Natural Sciences.
    Are algal oil yield estimations dependent on seasonal variation?2011In: Algae: The sustainable biomass for the future. Perspectives from the submariner project algae cooperation event Trelleborg, Sweden - September 28-29, 2011 / [ed] Cecilia Torres, Berlin, Germany: s.Pro-sustainable projects GmbH , 2011, p. 44-45Conference paper (Other (popular science, discussion, etc.))
  • 31.
    Olofsson, Martin
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Lamela, Teresa
    Necton SA, Olhao, Portugal.
    Nilsson, Emmelie
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Bergé, Jean-Pascal
    IFREMER, Nantes, France.
    del Pino, Victória
    Necton SA, Olhao, Portugal.
    Uronen, Pauliina
    Neste Oil, Ctr Technol, Porvoo, Finland.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Combined Effects of Nitrogen Concentration and Seasonal Changes on the Production of Lipids in Nannochloropsis oculata 2014In: Marine Drugs, ISSN 1660-3397, E-ISSN 1660-3397, Vol. 12, no 4, p. 1891-1910Article in journal (Refereed)
    Abstract [en]

    Instead of sole nutrient starvation to boost algal lipid production, we addressed nutrient limitation at two different seasons (autumn and spring) during outdoor cultivation in flat panel photobioreactors. Lipid accumulation, biomass and lipid productivity and changes in fatty acid composition of Nannochloropsis oculata were investigated under nitrogen (N) limitation (nitrate:phosphate N:P 5, N:P 2.5 molar ratio). N. oculata was able to maintain a high biomass productivity under N-limitation compared to N-sufficiency (N:P 20) at both seasons, which in spring resulted in nearly double lipid productivity under N-limited conditions (0.21 g L−1 day−1) compared to N-sufficiency (0.11 g L−1 day−1). Saturated and monounsaturated fatty acids increased from 76% to nearly 90% of total fatty acids in N-limited cultures. Higher biomass and lipid productivity in spring could, partly, be explained by higher irradiance, partly by greater harvesting rate (~30%). Our results indicate the potential for the production of algal high value products (i.e., polyunsaturated fatty acids) during both N-sufficiency and N-limitation. To meet the sustainability challenges of algal biomass production, we propose a dual-system process: Closed photobioreactors producing biomass for high value products and inoculum for larger raceway ponds recycling waste/exhaust streams to produce bulk chemicals for fuel, feed and industrial material.

  • 32.
    Olofsson, Martin
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Lindehoff, Elin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Frick, Brage
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Svensson, Fredrik
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Baltic Sea microalgae transform cement flue gas into valuable biomass2015In: Algal Research, ISSN 2211-9264, Vol. 11, p. 227-233Article in journal (Refereed)
    Abstract [en]

    We show high feasibility of using cement industrial flue gas as CO2 source for microalgal cultivation. The toxicity of cement flue gas (12-15% CO2) on algal biomass production and composition (lipids, proteins, carbohydrates) was tested using monocultures (Tetraselmis sp., green algae, Skeletonema marinoi, diatom) and natural brackish communities. The performance of a natural microalgal community dominated by spring diatoms was compared to a highly productive diatom monoculture S. marinoi fed with flue gas or air-CO2 mixture. Flue gas was not toxic to any of the microalgae tested. Instead we show high quality of microalgal biomass (lipids 20-30% DW, proteins 20-28% DW, carbohydrates 15-30% DW) and high production when cultivated with flue gas addition compared to CO2-air. Brackish Baltic Sea microalgal communities performed equally or better in terms of biomass quality and production than documented monocultures of diatom and green algae, often used in algal research and development. Hence, we conclude that microalgae should be included in biological solutions to transform waste into renewable resources in coastal waters. (C) 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  • 33.
    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.

  • 34.
    Parsland, Charlotte
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Nickel-substituted Ba-hexaaluminates as catalysts stem-reforming of tars2013In: CRS-2, Catalysis for Renewable sources: Fuel. Energy, Chemicals Book of Abstracts / [ed] Vadim Yakovlev, Boreskov Institute of Catalysis, Novosibirsk: Boreskov Institute of Catalysis , 2013, p. 62-63Conference paper (Refereed)
    Abstract [en]

    Gasification of woody biomass converts the solid organic material into a gaseous product with a higher energy value and by this mean provide a more carbon neutral gaseous fuel than the common fossil ones. The produced raw gas mainly contains H2, CO, CO2, CH4, H2O and N2 together with organic (tars) and inorganic (alkali) components and fine particulates. The amount of impurities in the raw gas is dependent of the fuel properties and the gasification process technology and the quality of the resulting product gas determines its suitability for more advanced purposes. One of the major general concerns within the gasification processes is the formation of tars. Tars are a vast group of polyaromatic hydrocarbons and there are a number of definitions. On an EU/IEA/US-DOE discussion meeting in Brussels 1998, a number of experts agreed on a simplified classification of tars as “all organic contaminants with a molecular weight larger than benzene” [1]. The aim of this work is to investigate the steam reforming ability of a catalytic material not previously tested in this type of application in order to achieve an energy-efficient and high-quality gasification gas. The physical demands for an optimal tar-cracking and steam reforming catalyst is a high surface area, thermal stability, mechanical strength and a capacity to withstand high gas velocities, poisons such as H2S or NH3 and other impurities. Additionally it has to resist the process steam, as steam is well known to enhance sintering of porous materials. Nickel is a familiar catalyst for steam reforming. Hexaaluminate is a well-known catalyst support with properties that may answer to the requests of a non-abrasive, high-temperaturestable and steam-resistant catalytic material. It is a structural oxide where the general formula for the doped unit cell is MIMII(x)Al12-xO19-d where MI represents the mirror plane cation and MII is the aluminum site in the lattice where substitution may occur. MII is often a transition metal ion of the same size and charge as aluminum. MI is an ion located in the mirror plane of the structure and it is a large metal ion, often from the alkaline, alkaline earth or rare earth metal group. The stability and activity of these materials are often being related to the properties of MI and MII. The activity is highly dependent on the nature of the Al-substituted metal and partially by the nature of MII [2]. In our experiments we have tested the catalytic capacity of Ni-substituted Ba-hexaaluminates synthesised by the sol-gel method [3], both in a model set-up and in a gasification plant. In the lab-scale set-up different catalyst-formulae was tested under various temperatures for reforming of methyl-naphthalene. The results show a good catalytic activity for tar-breakdown. As expected the substitution level of Ni is clearly coupled to the reaction temperature. With the most highly substituted Ni-Bahexaaluminate at 900 °C all of the methyl-naphthalene has been broken downtogether with all of the resulting hydrocarbons. The Ni-Bahexaaluminate catalyst has recently also been tested in real process-gas.

    These results are still to be evaluated, but indicate a positive result.

     

     

  • 35.
    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.

  • 36.
    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.

  • 37.
    Razmjoo, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Hermansson, Sven
    RISE Research Institutes of 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 furnace2018In: Journal of the Energy Institute, ISSN 1743-9671Article 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.

  • 38.
    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)
  • 39.
    Rupar, Katarina
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, Institutionen för biovetenskaper och processteknik.
    Sanati, Mehri
    The Release of Organic Compounds during Biomass Drying depends upon the feedstock and/or altering Drying Heating Medium2003In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 25, no 6, p. 615-622Article in journal (Refereed)
    Abstract [en]

    The release of organic compounds during the drying of biomass is a potential environmental problem, it may contributeto air pollution or eutrophication. In many countries there are legal restrictions on the amounts of terpenes that may bereleased into the atmosphere. When considering bioenergy in future energy systems, it is important that information on theenvironmental e-ects is available. The emissions of organic compounds from di-erent green and dried biofuels that have beendried in hot air and steam medium, were analyzed by using di-erent techniques. Gas chromatography and gas chromatographymass spectrometry have been used to identify the organic matter. The terpene content was signi2cantly a-ected by thefollowing factors: changing of the drying medium and the way the same biomass was handled from di-erent localities inSweden. Comparison between spectra from dried and green fuels reveal that the main compounds emitted during dryingare monoterpene and sesquiterpene hydrocarbons, while the emissions of diterpene hydrocarbons seem to be negligible. Therelative proportionality between emitted monoterpene, diterpene and sesquiterpene change when the drying medium shiftsfrom steam to hot air. The obtained result of this work implies a parameter optimization study of the dryer with regard toenvironmental impact. With assistance of this result it might be foreseen that choice of special drying medium, diversity ofbiomass and low temperature reduce the emissions. A thermo-gravimetric analyzer was used for investigating the biomassdrying rate.

  • 40.
    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.

  • 41.
    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.

  • 42.
    Svensson, Helena
    et al.
    Chemical Engineering, Lund University.
    Tunå, Per
    Chemical Engineering, Lund University.
    Hulteberg, Christian
    Chemical Engineering, Lund University.
    Brandin, Jan
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Modeling of soot formation during partial oxidation of producer gas2013In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 106, p. 271-278Article in journal (Refereed)
    Abstract [en]

    Soot formation in a reverse-flow partial-oxidation reactor for reforming of gasifier producer gas has been studied. The process was modeled using a detailed reaction mechanism to describe the kinetics of soot formation. The numerical model was validated against experimental data from the literature and showed good agreement with reported data. Nine cases with different gas compositions were simulated in order to study the effects of water, hydrogen and methane content of the gas. The CO and CO2 contents, as well as the tar content of the gas, were also varied to study their effects on soot formation. The results showed that the steam and hydrogen content of the inlet gas had less impact on the soot formation than expected, while the methane content greatly influenced the soot formation. Increasing the CO2 content of the gas reduced the amount of soot formed and gave a higher energy efficiency and methane conversion. In the case of no tar in the incoming gas the soot formation was significantly reduced. It can be concluded that removing the tar in an energy efficient way, prior to the partial oxidation reactor, will greatly reduce the amount of soot formed. Further investigation of tar reduction is needed and experimental research into this process is ongoing.

  • 43.
    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 macroalgae Saccharina latissima2018Independent 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.

  • 44.
    Trischler, Johann
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Strategic raw material supply for the particleboard-producing industry in Europe: Problems and challenges2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Particleboard was invented to increase the utilization of wood and it soon became an important core material for furniture production. Nowadays, other industries such as the pulp and papermaking industry and the thermal energy recovery industry claim the same type of raw material. This leads to increasing competition and higher prices than in the past when that kind of wood raw material was widely available and of low price. The particleboard-producing industry is therefore seeking opportunities to reduce the competition and ensure the future supply of lignocellulosic raw material for their products.

    The purpose of the work summarised in this thesis was to investigate the strategic supply of lignocellulosic raw materials for particleboard production and to evaluate alternatives for the supply of lignocellulosic raw material for particleboard production.

    To encompass the complex field of strategic raw material supply, several publications have considered different stages along the supply chain. These papers range from empirical studies to practical tests on a laboratory scale. In this thesis, some of the papers are linked together, building the base for the overall results.

    The results show that the task of increasing the supply of lignocellulosic raw material as primary raw material source is limited by several factors, but that improved product design coupled with a suitable recycling concept can greatly increase the availability of lignocellulosic raw material as a secondary source. Alternatively, the use of non-wood plants might be an opportunity to substitute wood as raw material but there are still some problems relating to the particle properties which must be overcome first.

  • 45.
    Truong, Nguyen Le
    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.
    Climate effects of biomass use in integrated energysystems2017In: ECEEE Summer Study proceedings 2017, European Council for an Energy Efficient Economy (ECEEE), 2017, p. 911-920Conference paper (Refereed)
    Abstract [en]

    Biomass is a key resource in a society based on renewable energy, but is a limited resource and the use of biomass in one sector will influence its availability for other sectors. The global energy system is heavily dependent on fossil fuels, and the climate impacts of CO2 occur regardless of the source of emissions. As a result, the climatic effects of biomass use in an energy system depend largely on which biomass feedstock and bioenergy pathway is being used, and what type of fossil fuel pathway is being replaced. In this study, we evaluate the CO2 emissions and climate effects of woody biomass and fossil fuel use. We analyse the potential production of electricity, heat or transport distance when using one kWh of woody biomass and fossil energy system designed to provide the same service to society as the most energy efficient bioenergy systems. The fuel cycle inputs are included in the analyses and are based on different state-of-the art as well as emerging technologies for energy conversion. We quantify the primary energy use and annual CO2 emission of different bioenergy and fossil alternatives. We then calculate the cumulative CO2 emission and climate effects in terms of cumulative radiative forcing for the fossil and bioenergy systems. The results show that primary energy use, CO2 emission, and cumulative radiative forcing vary strongly between the studied alternatives. The use of bioelectricity and electric vehicles instead of biomotor fuel-based vehicles gives about twice the transport distance per unit of consumed woody biomass. Integrated energy systems that supply a package of energy services including electricity, heat and transport distance reduce the primary energy use and increase the climate benefits of woody biomass. The replacement of coal for heat and electricity production by the here studied woody biomass gives large climate benefits immediately.

  • 46.
    Truong, Nguyen Le
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Gustavsson, Leif
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Sathre, Roger
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Primary energy and climate change effects of forest residues and fossil coal for electricity production with and without carbon capture and storage2016In: 24th European Biomass Conference and Exhibition. Hamburg, Germany, June 23-26, 2016, Amsterdam, The Netherlands, ETA-Florence Renewable Energies , 2016, p. 1394-1401Conference paper (Other academic)
    Abstract [en]

    Forest biomass that is currently unused, such as thinning and harvest residues, could be mobilized to produce bioelectricity, to mitigate climate change. An emerging technology for climate change mitigation is carbon capture and storage (CCS), which can reduce CO2 emissions from energy conversion facilities, but at a cost of additional fuel needed for process energy requirements. The use of forest residues that otherwise would decay on the forest floor, in an energy plant equipped with CCS, could result in a net reduction of CO2 emission to the atmosphere, while producing usable electricity. In this study, we analyse the climate change effects of using either coal or forest residues to produce electricity in large-scale conversion plants. We estimate the primary energy use, annual CO2 emission, annual change in CO2 concentration in the atmosphere and cumulative radiative forcing (CRF) of different energy systems that all produce the same quantity of electricity. We also consider the potential effects of future technology developments including gasification and integrated carbon capture processes. The results show that using forest residues to replace coal with current conversion technologies slightly increase the combustion CO2 emission, but in the long term give much lower net CO2 emission and mitigate climate change. The application of emerging gasification technology reduces primary energy use and CO2 emission compared to current technology, and hence increases the climate benefits. The use of CCS requires larger quantities of fuel, but could strongly reduce the CO2 emissions from conversion facilities, thus increasing the carbon benefits per unit of forest biomass used.

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