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  • 1.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Frodeson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Kartläggning och nulägesbeskrivning av pelletskedjan2011Report (Other academic)
  • 2.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Frodeson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Lösningarna finns! Är pelletsproducenterna medvetna om problemen?2011In: Bioenergi: utmaningar och möjligheter / [ed] Delin, Karin, Persson, Lars, Wikström, Per-Arne, Gävle: Region Gävleborg , 2011, p. 25-29Chapter in book (Other academic)
    Abstract [sv]

    Sverige är inte längre världsledande som pelletsproducent. USA producerar allra mest pellets i världen. Kanada och Ryssland producerar också allt mer pellets. Ingen av dessa länder har någon omfattande inhemsk konsumtion. I stort sett all pellets exporteras och det sker huvudsakligen till Europa. Sannolikt kommer det att leda till att priset på pellets i Europa sjunker, med följd att lönsamheten för svenska pelletsproducenter minskar.

  • 3.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Frodeson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Varför får inte villaägaren driva kvalitetsutvecklingen på bränslepellets?2011In: Bioenergi: utmaningar och möjligheter / [ed] K. Delin, L. Persson, P.-A. Wikström, Gävle: Region Gävleborg , 2011, p. 31-33Chapter in book (Other academic)
  • 4.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Frodeson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Nordgren, Daniel
    Innventia, Box 5604, SE-11486 Stockholm, Sweden.
    Tomani, Per
    Innventia, Box 5604, SE-11486 Stockholm, Sweden.
    The effects of kraft lignin additives on wood fuel pellet quality, energy use and shelf life2013In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 112, no 0, p. 64-69Article in journal (Refereed)
    Abstract [en]

    In 2011, the total consumption of pellets in Sweden amounted to 1.9 million tons, which represents an energy value of 9 TWh. The pellets are used in large-scale as well as in small-scale applications, and increased demands on pellet quality are likely to force pellet producers to improve on the pellet properties. One way of increasing pellet quality is by using additives. The purpose of this article, therefore, is to examine kraft lignin as an additive. Pelletswere produced in a small industrial pellet press located at KarlstadUniversity, Karlstad, Sweden, and 1–4% of kraft lignin was added to the pellets. The results indicate that the addition of an increased amount of kraft lignin to the pellets increases their mechanical durability and their lengths. The results also indicate that dry kraft lignin yields pellets with higher durability as compared to wet kraft lignin. The energy demand was unaffected by the increased use of kraft lignin. The general results presented in this paper are useful for producers of lignin, pellet producers and end-users of pellets, who are interested in developing their products and/or improving the production processes.

  • 5.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Frodesson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Tillsatser som kvalitetshöjare för pellets2011Report (Other academic)
  • 6.
    Berghel, Jonas
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    From sawdust to pellets. Still a challenge...2012In: Public Service Review European Union, no 33, p. 398-399Article in journal (Other academic)
  • 7.
    Eskandari, Samieh
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Mohammadi, Ali
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Sandberg, Maria
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Eckstein, Rolf Lutz
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Hedberg, Kjell
    Ulf Ahlden Ingenjörsfirma, Upplands Väsby.
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Hydrochar-Amended Substrates for Production of Containerized Pine Tree Seedlings under Different Fertilization Regimes2019In: Agronomy, E-ISSN 2073-4395, Vol. 9, no 7, p. 1-17Article in journal (Refereed)
    Abstract [en]

    There is a growing body of research that recognizes the potentials of biochar application in agricultural production systems. However, little is known about the effects of biochar, especially hydrochar, on production of containerized seedlings under nursery conditions. This study aimed to test the effects of hydrochar application on growth, quality, nutrient and heavy metal contents, and mycorrhizal association of containerized pine seedlings. The hydrochar used in this study was produced through hydrothermal carbonization of paper mill biosludge at 200 °C. Two forms of hydrochar (powder and pellet) were mixed with peat at ratios of 10% and 20% (v/v) under three levels of applied commercial fertilizer (nil, half and full rates). Application of hydrochar had positive or neutral effects on shoot biomass and stem diameter compared with control seedlings (without hydrochar) under tested fertilizer levels. Analysis of the natural logarithmic response ratios (LnRR) of quality index and nutrient and heavy metal uptake revealed that application of 20% (v/v) hydrochar powder or pellet with 50% fertilizer resulted in same quality pine seedlings with similar heavy metal (Cu, Ni, Pb, Zn and Cr) and nutrient (P, K, Ca and Mg) contents as untreated seedlings supplied with 100% fertilizer. Colonization percentage by ectomycorrhizae significantly increased when either forms of hydrochar were applied at a rate of 20% under unfertilized condition. The results of this study implied that application of proper rates of hydrochar from biosludge with adjusted levels of liquid fertilizer may reduce fertilizer requirements in pine nurseries.

  • 8.
    Frodeson, Stefan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Berghel, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Ståhl, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Romlin, Carl
    Drinor AB, Karlstad.
    Thelander, Alexander
    Drinor AB, Karlstad,.
    The Potential for a Pellet Plant to Become a Biorefinery2019In: Processes, ISSN 2227-9717, E-ISSN 1099-5862, Vol. 7, no 4, p. 1-11, article id 233Article in journal (Refereed)
    Abstract [en]

    The use of bioenergy has increased globally in recent years, as has the utilization of biomaterials for various new product solutions through various biorefinery concepts. In this study, we introduce the concept of using a mechanical dewatering press in combination with thermal drying in a pellet plant. The purpose of the study is to increase the understanding of the effects a mechanical dewatering press has in a pellet production chain and investigate whether a pellet plant could thus become a biorefinery. The evaluations in this study are based on industrial data and initial tests at the university. The results show that the concept of using the mechanical dewatering press together with a packed moving bed dryer reduces energy use by 50%, compared to using only a packed moving bed dryer. The press water could be used as a raw material for biogas, bioplastics, and biohydrogen. Hence, this study points out the possibilities of a pellet plant increasing the efficiency of the drying step, while moving towards becoming a biorefinery.

  • 9.
    From-Aldaron, M.
    et al.
    Karlstad University.
    Sandberg, Maria
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Low Dosage Chemical Treatment for Improved Oxygenation of Pulp Mill Effluents2018In: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 144, no 3, article id 06017012Article in journal (Refereed)
    Abstract [en]

    Most pulp and paper mills use aerobic biological treatment for their effluents. Aeration is the single most energy intensive process of a treatment plant. Surfactants, commonly occurring in pulping wastewaters, have been shown to decrease the oxygen transfer rate. The aim of this study was to decrease the surface activity of surfactants and thereby increase the oxygen transfer rate in pulp mill effluents by the use of chemical pretreatment in very low doses. Trials using 5 g/m(3) ferric iron showed statistically significant improvement on both k(L)a(@20) and surface tension. No sludge was precipitated owing to the very low ferric iron dosage. The novel use of chemical pretreatment, in very low doses, aiming specifically at improving oxygen transfer rate, is a promising concept for reducing the need for aeration in wastewater treatment and thus lower the electricity requirement of the wastewater treatment plant. (c) 2017 American Society of Civil Engineers.

  • 10.
    Granstrom, Karin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Javeed, Atif
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Emissions from sawdust in packed moving bed dryers and subsequent pellet production2016In: Drying Technology, ISSN 0737-3937, E-ISSN 1532-2300, Vol. 34, no 3, p. 258-266Article in journal (Refereed)
    Abstract [en]

    This study quantifies emissions of hydrocarbon terpenes from the drying of sawdust in packed moving bed dryers, through the production chain to the finished pellets, and determines the parameters suitable for emission control. The terpene content in softwood sawdust and pellets was analyzed using gas chromatography. The distribution of VOC emissions over the bed was measured with a flame ionization detector. After drying, 30-40% of the initial terpenes remain in the wood, 20-30% remain after grinding, and 10-15% remain after pelleting. Dryer emissions correlate with residence time and final sawdust moisture content. Pellet press emissions correlate with pellet moisture content.

  • 11.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    A Method to Measure Emissions from Dryers with Diffuse Leakages2003Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    The timber kiln drying process emits volatile organic compounds (VOC), which have long been recognised as one of the major air pollutants.



    This poster describes a novel method to measure emission from dryers and presents some results achieved.



    The method resolves the known difficulties caused by diffuse emissions, and also solves the problems associated with high moisture content of the drying medium (i.e. interference with VOC measuring equipment). The basic idea is to use the emitted water vapour to determine the volume of exhaust flow, while a dry ice trap is used both to preconcentrate emitted VOCs and to determine the moisture content of the drying medium.



    The feasibility and some advantages of this method was demonstrated measuring VOC emissions to air from a dryer with recirculating drying medium and in steady-state operation.



    The method was validated in two ways: using the controlled addition method and by comparison with Soxhlet extraction. The additions was detected to over 90%. The cold trap method detected a substance (p-cymene) that was not detected by Soxhlet extraction.

  • 12.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    A method to measure emissions from dryers with diffuse leakages II. Sensitivity studies2005In: Drying Technology 3(5):1127-1140, 2005Article in journal (Refereed)
    Abstract [en]

    Measurements of VOC emissions from dryers have several known difficulties. An earlier published method to measure emissions of VOC from dryers deals with problems associated with diffuse emissions and high moisture content of the drying medium([1]) In this article, a different calculation path are used and the influence of the main parameters are studied in more depth. For one experiment, confidence intervals for all of the parameters are calculated. Experimentally induced uncertainties are found to be more important than a theoretically important parameter. Suggestions are made on how to increase accuracy.

  • 13.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    A method to measure emissions from dryers with diffuse leakages, using evaporated water as a tracer2003In: Drying Technology 21(7):1197-1214, 2003Article in journal (Refereed)
    Abstract [en]

    This paper describes a novel method to measure emission from

    dryers. The method resolves the known diffculties caused by diffuse emissions,and also solves the problems associated with high moisture content of the drying medium. The basic idea is to use water vapor to determine the exhaust flow, while a dry ice trap is used both to preconcentrate emitted VOCs and to determine the moisture content of the drying medium.

  • 14.
    Granström, Karin
    Karlstad University, Division for Engineering Sciences, Physics and Mathematics.
    Biogenic emissions of monoterpenes in Sweden: a review with implications for modellingManuscript (Other (popular science, discussion, etc.))
  • 15.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Effect of sawdust age on the storage quality of wood pellets2010Conference paper (Refereed)
  • 16.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Emissions of hexanal and terpenes during storage of solid wood fuels2010In: Forest products journal, ISSN 0015-7473, Vol. 60, no 1, p. 27-32Article in journal (Refereed)
  • 17.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Emissions of hexanal and terpenes during storage of wood sawdust and pellets2009Conference paper (Other (popular science, discussion, etc.))
  • 18.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Emissions of monoterpenes and VOC during drying of sawdust in a continuous spouted bed2003In: Forest Products Journal 53(10):48-55,2003Article in journal (Refereed)
    Abstract [en]

    Emissions of volatile hydrocarbons are considered an environmental problem and a health problem. A wood-drying process is a source of volatile organic compound (VOC) emissions. Emissions of monoterpenes, as well as total VOCs, from a pilot-scale

    continuous spouted bed dryer have been investigated regarding the influence of the drying medium temperature and the final sawdust moisture content. The emissions from sawdust of Norway spruce (Picea abies), dried at three temperature schedules (140, 170 and 200°C), was analyzed by a gas chromatograph with a mass

    spectrometric detector and with a flame ionization detector. Emissions of terpenes and VOC per ovendry weight increased rapidly when the sawdust moisture content was reduced below 12 percent (wb).The concentration of VOCs in the drying medium, and the

    amount of emitted monoterpenes, increased with drying medium temperature. The composition of different monoterpenes in the drying medium was not influenced by the sawdust s final moisture content. The relative amount of less volatile monoterpenes increased with drying medium temperature

  • 19.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Emissions of Monoterpenes and VOC during Drying of Sawdust in a Continuous spouted bed2002Conference paper (Refereed)
  • 20.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Emissions of sesquiterpenes from spruce sawdust during drying2006Conference paper (Other (popular science, discussion, etc.))
  • 21.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Emissions of sesquiterpenes from spruce sawdust during drying2009In: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 67, no 3, p. 343-350Article in journal (Refereed)
  • 22.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Emissions of volatile organic compounds during drying of wood2002Licentiate thesis, monograph (Other academic)
  • 23.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Emissions of volatile organic compounds from wood2005Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The central aim of this thesis is to support the efforts to counteract certain environmental problems caused by emissions of volatile organic compounds.



    The purpose of this work was (1) to develop a method to establish the amount of emitted substances from dryers, (2) to determine the effect of drying medium temperature and end moisture content of the processed material on emissions of monoterpenes and other hydrocarbons, (3) to examine the emissions of monoterpenes during production of pellets, and (4) to examine the natural emissions from forests with an eye to implications for modelling.



    The measurement method (1) resolves the difficulties caused by diffuse emissions, and also solves the problems associated with high moisture content of the drying medium. The basic idea is to use water vapour to determine the exhaust flow, and to use a dry ice trap both to preconcentrate emitted VOCs and to determine the moisture content of the drying medium. The method, as used in this paper, has an uncertainty of 13% using a 95% confidence interval.



    Emissions from a spouted bed (2) in continuous operation drying Norway Spruce sawdust at temperatures of 140°C, 170°C or 200°C were analysed with FID and GC-MS. When the sawdust end moisture content was reduced below 10%wb, emissions of terpenes and of total VOC per oven dry weight increased rapidly. The increased temperature of the drying medium entering the drying tower also caused an increase in the amounts of emitted monoterpenes at sawdust moisture contents below the fibre saturation point.



    Examination of sawdust and wood pellets from different pellets producers (3) revealed that most of the terpene emissions take place during the drying step, with flue gas dryers causing higher emissions than steam dryers. Almost all of the volatile terpenes remaining in wood after drying were released during pelleting. Increased terpene emissions during the pelleting process were found when sawdust with a higher moisture content was used.



    Terpenes emitted naturally from vegetation can have adverse environmental impacts. Factors affecting terpene emissions from tree species in Sweden were reviewed (4). Models for prediction of terpene fluxes should include not only temperature but also light intensity, seasonal variation, and a base level of herbivory and insect predation. Prediction of high concentrations of ambient terpenes demand sufficient resolution to capture emission peaks, e.g., those caused by bud break.

  • 24.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Impregnerad träkubb som bränsle2005Report (Other academic)
    Abstract [sv]

    Träkubb med fuktkvot på knappt 6% impregnerades med en olja med effektivt värmevärde på 10,3 kWh/kg. Kubb som nedsänkts i olja under 6 till 127 timmar fick oljehalter räknat på torrsubstans på 75 till 105% för tall och 90 till 115% för gran. Vid förvaring i 50°C läckte olja från kubb med oljehalt över 110% för gran och 100% för tall. Kubb som sprayats med vatten till 20% fukthalt och med olja till 5 kWh/kg gav inga problem med läckage. Förbränning av sådan kubb gav emissioner av NO, NOx, SO2 och CO av samma storleksordning som vid eldning med pellets. Det var nödvändigt att göra smärre justeringar av pelletsbrännarens glödstift för att tändningen skulle fungera. Inmatning med matarskruv fungerade dåligt med kubbens nuvarande form. Frysning av kubben verkade inte påverka dess tändningsegenskaper negativt

  • 25.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Kolväten från träbränsleindustrin: sågverk, trätorkar och pelletspressar2009Report (Other (popular science, discussion, etc.))
  • 26.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Kolväten från träbränsleindustrin: sågverk, trätorkar och pelletspressar: Handbok för myndigheter och industri2008Book (Refereed)
    Abstract [sv]

    Detta faktablad innehåller snabb och lättillgänglig information om kolväteutsläpp från produktionen av träbaserade fasta biobränslen, specifikt från sågning, trätorkning och pelletspressning. Faktabladet är tänkt som ett hjälpmedel för länsstyrelser och kommuner vid handläggning av tillsyns- och prövningsärenden. Skriften ska också vara ett stöd för verksamhetsutövare.

    Frågor som behandlas är (1) typiska utsläppsnivåer för kolväten från sågverk, torkar och pelleteringsanläggningar, (2) klargörande av hur olika produktionsmetoder och råvaror skiljer sig åt med avseende på mängden kolväten som avgår, (3) en uppskattning av betydelsen av antropogena utsläpp jämfört med de naturliga emissionerna av terpener från barrskog, och (4) förslag på hur kolväteutsläpp från träbränsleindustrin kan minskas vid behov.

  • 27.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ny ångtorkningsteknik i mellanstor skala2003Conference paper (Other (popular science, discussion, etc.))
  • 28.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    On the environmental aspects of pellets production2011Conference paper (Refereed)
  • 29.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Reduced VOC Emissions from Birch Sawdust Dried in a Steam Dryer2003Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Large amounts of sawdust are dried for production of particleboard and pellets. During drying of wood, volatile organic compounds (VOC) are emitted. VOC emissions contribute in the presence of nitrogen oxides and sunlight to the formation of ground level ozone and other harmful photo-oxidants.



    While several studies have been made on the amount and composition of emissions from softwoods during drying, hardwoods have been given less attention. Hardwoods have different wood structure and also differ in the chemical composition of volatiles.



    In this study emissions of VOC from birch sawdust during drying in a steam dryer at atmospheric pressure were investigated. The drier was a pilot scale continuous spouted bed. Both the amount and the composition of emissions were determined. The sawdust was dried to different moisture contents in two drying medium temperatures (170 °C and 200 °C).



    The results are compared to the emissions from softwoods dried in similar conditions. The results of this study should help to reduce emissions of volatile hydrocarbons during drying of hardwood sawdust and wood chips.

  • 30.
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Regler för hantering av rötrest2014Report (Other academic)
    Abstract [sv]

    Innehållsförteckning

    INLEDNING

    PROBLEM MED ATT TA TILLVARA RÖTREST

    Tungmetaller

    Smitta

    REGLERING AV ANVÄNDANDET AV RÖTREST SOM GÖDNING

    Certifiering av biogödsel

    Hygieniseringskrav för biogödsel

    Certifiering av rötslam

    Hygieniseringskrav för rötslam

    ACCEPTANS?

    MÖJLIGHETER OCH RISKER MED SAMRÖTNING

    REFERENSER

  • 31.
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Resource recovery from pulp and paper mills by adaptation of their wastewater treatment to biogas production2014In: 19th European Biosolids & Organic Resources Conference and Exhibition, Manchester, UK, 17-19 November 2014., 2014Conference paper (Other academic)
  • 32.
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Sawdust age affect aldehyde emissions in wood pellets2014In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 126, p. 219-223Article in journal (Refereed)
    Abstract [en]

    The environmental and energy policies in most nations worldwide aim at replacing fossil fuels with renewable sources of energy. The use of wood pellets made from sawdust is rapidly increasing. Wood pellets are a refined compacted fuel with high energy density and low emissions during combustion. Sawdust and wood pellets may be stored for several months due to seasonal demand variation and wood-fuel trade. Wood contains unsaturated fatty acids susceptible to oxidation, a process commonly referred to as fats going rancid. The level of oxidation in pellets is an important parameter of pellets quality as oxidation during storage causes problems such as self-ignition of pellets stored in silos and emissions of malodorous compounds. The purpose of this work was to investigate the effect of the age of the raw material on the oxidation caused aldehyde emissions from wood pellets. Pellets were produced from Scots pine (Pinus sylvestris) sawdust that was either freshly sawn or had been stored for 4 months. The pellets were then stored in either 18 °C or in 40 °C. The formation of the aldehyde hexanal was analyzed with static headspace and gas chromatography. Pellets made from fresh sawdust were low-emitting after 80 days, whereas pellets made from aged sawdust did not reach the same low level until 190 days after production. This held true whether the pellets were stored in 18 °C or in 40 °C. The aged sawdust pellets had maximum emissions at the same time as the emissions ceased from the fresh sawdust pellets. A key conclusion is that when a low level of aldehyde emissions is required during storage, the pellets should be produced of sawdust that is freshly sawn.

  • 33.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Some reflections on the modelling of biogenic emissions of monoterpenes in the boreal zone2008In: / [ed] Edited by C.A. Brebbia, J.W.S. Longhurst, UK: Wessex Institute of Technology , 2008Conference paper (Refereed)
    Abstract [en]

    Trees emit volatile organic compounds, mostly monoterpenes and isoprene. These biogenic substances are the dominant volatile organic compounds in air in forested regions. They contribute to the formation of tropospheric ozone and other photochemical oxidants if mixed with polluted air from urban areas. Increased ozone levels hamper photosynthesis and thus have a negative impact on the growth of forests and crops. Terpene flux estimations are needed for models of atmospheric chemistry and for carbon budgets. Several models of natural terpene emission have been constructed, both in a global scale and for various regions. Ideally, a model of natural terpene emissions should show the terpene flux at different times of day and year, at different weather conditions, and for different ecosystems. Its resolution should be sufficient to show short emission peaks. It should also be able to accommodate extreme events like pest outbreaks and serious storms, especially since those are expected to become more common due to global warming. An examination of the scientific literature on monoterpene content in trees and emission fluxes for the dominant boreal forest tree species shows that models aiming to predict terpene fluxes from natural sources over time should include the factors temperature and light intensity, and possibly also take into account the seasonal variation of terpene levels in trees. As wood tissue damage increases emissions, a base level of herbivory and insect predation should be estimated and included. When identification of high concentrations is important, models should have sufficient resolution to capture the emission peaks found, for example, at bud break. The temperature dependence is shown to vary sufficiently between different tree species to motivate using specific values for the ecosystems examined.

  • 34.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Underestimation of terpene exposure in the Nordic wood industry2009In: Journal of Occupational and Environmental Hygiene, ISSN 1545-9624, E-ISSN 1545-9632, Vol. 7, no 3, p. 144-151Article in journal (Refereed)
  • 35.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Utsläpp av lättflyktiga kolväten vid torkning av biobränslen: Värmeforskrapport 7452001Report (Refereed)
    Abstract [sv]

    Projektet omfattar en undersökning av vilka ämnen som avgår vid torkning av gran- och furuspån, samt data över energieffektivitet, vid olika torkbetingelser. Målet är att minimera både emissioner och energibehov, i syfte att minska miljö- och hälsoeffekter av torkning, samt öka det ekonomiska utbytet av torkningen. Därmed kan den primära målgruppen sågverk få bättre möjligheter att producera pellets och briketter.



    Genomförande: Torkningen har skett under atmosfärstryck i en fluidiserad tork i pilotskala, med recirkulerande eller icke-recirkulerande torkmedium. Emissionerna av kolväten har mätts med flamjonisations-detektor (FID). En analys av vilka kolväten som ingår i emissionerna har gjorts med en gaskromatograf med masspektrometer (GC/MS).



    Resultaten från GC/MS redovisas som vikt monoterpener per vikt torrsubstans sågspån. Undersökningar av terpenavgång vid torkning med recirkulerande torkgas visar att långt driven torkning medför större terpenavgång. Så länge spånen inte torkas till fukthalter (vatten/totalvikt) under ca 10% är mängden terpener som avgår liten, men om spånen torkas till lägre fukthalter så ökar terpenavgången snabbt. Mängden avgivna terpener ökar med temperaturen på torkgasen in till torktornet för bestämd fukthalt på utgående spån. De dominerande monoterpenerna är a-pinen, b-pinen och 3-karen. Därnäst kommer myrcen och limonen. Fördelningen mellan olika monoterpener i emissionerna kan skilja sig för spån som sågats olika dagar. y-terpinen har hittats vid torkning av furuspån men inte i granspån. Det inbördes mängdförhållandet av olika monoterpener i torkgasen verkar inte påverkas av hur långt torkningen av spånen drivs. En ökad temperatur på torkgasen in till torktornet påverkar fördel-nin-gen av terpener i torkgasen på så sätt att andelen av myrcen och limonen (de högkokande mono-terpenerna) ökar relativt de andra monoterpenerna.



    Flamjonisationsdetektorns resultat redovisas som koncentration av kolväten i torkgasen och som vikt kolväten per vikt torrsubstans sågspån. Mätningar med FID visar att koncentrationen av kolväten då torkgasen recirkuleras når stationärt tillstånd och att kolvätekoncentrationen vid bestämd spånslutfukthalt ökar med temperaturen på torkgas in till torktornet. En massbalans för recirkulerande torkgas visar att kolvätekoncentrationen i torkgasen vid bestämd fukthalt på in- och utgående spån är proportionell mot kolväteavgången per torrsubstans, medan torkgasflödet och spånflödet inte påverkar kolvätekoncentrationen. Undersökningar av kolväteavgången per torrsubstans visar att den ökar med minskad slutfukthalt och ökande temperatur på torkgas in till torktornet.



    Energieffektiviteten förbättras då temperaturen på torkgas in till torktornet ökar, men försämras då spånets fukthalt sjunker oavsett temperatur på torkgas in till torktornet. Energieffektiviteten var högre då torken kördes med återcirkulering av torkgasen.



    En viktig slutsats är att fluidiserad tork ska använda recirkulering av torkmediet. En annan viktig slutsats är att för att minimera emissionerna vid torken bör temperaturen på torkgas in till torktornet hållas låg och utgående spånfukthalt vara mer än ca 10%.



    Nyckelord: VOC, terpener, fluidiserad bädd, torkning, energieffektivitet

  • 36.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Utvärdering av miljöanpassat reningsverk i Hammarö kommun ur ett kretsloppsperspektiv - minskning av transportarbete och näringsläckage2007Report (Refereed)
    Abstract [sv]

    Hammarö kommuns reningsverk vid Sätter har biologisk rening av kväve och fosfor. Det byggdes för att få bort ineffektiva enskilda avlopp och istället skapa ett ekologiskt hållbart kretslopp för lokalt återbruk av avlopp och organiskt hushållsavfall. Ledningsnätet är ännu inte fullt utbyggt. Här analyseras vinsterna med de olika faserna i en kommande utbyggnad av ledningsnätet. Att hushållsavfallets organiska del transporteras i avloppsledningarna har hittills inte påverkat soprutter eller hämtningsfrekvens, så transportarbetet för sopor är oförändrat. Genomslaget för avfallskvarnar är när denna studie görs 35%, vilket inte är tillräckligt för att märkbart påverka sopmängderna. En större acceptans för avfallskvarnar

    behövs. Om nuvarande genomslag i befintlig bebyggelse kvarstår, men avfallskvarn blir obligatoriskt i nybyggda områden, så minskar mängden näringsämnen i de sopor som går till förbränning med 54%. Transportarbetet för slam från östra Hammarö var före byggandet av Sätterverket 12600 km/år. Det minskar till 5500 km/år efter utbyggnaden av ledningsnät till Rud och Torp, till 3000 km/år när ledningsnät dragits till östraste Hammarö, för att helt upphöra när Tynäs kopplas på. I södra Hammarö behålls enskilda avlopp, men transportavståndet för producerat slam blir kortare. Transporterna minskar därför från 4500 km/år till 4200 km/år, vilket motsvarar 170 liter drivmedel. Ett fullt utbyggt ledningsnät på östra Hammarö reducerar transporterna med 60%, vilket motsvarar en

    drivmedelsförbrukning på 6900 liter/år. När anslutningen av Rud och Torp är genomförd minskar läckaget av kväve med 1080 kg och av fosfor med 190 kg. Inkoppling av östraste Hammarö minskar näringsämnesläckaget med 480 kg kväve och 85 kg fosfor. När Tynäs ansluts minskas läckaget med ytterligare 542 kg kväve och 95 kg fosfor

  • 37.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Utvärdering av miljöanpassat reningsverk i Hammarö kommun ur ett kretsloppsperspektiv förstudie för etablering av nollpunkt2005Report (Refereed)
    Abstract [sv]

    Hammarö kommun bygger ett nytt reningsverk för avloppsvatten och organiskt hushållsavfall. Reningsverket består av en förbehandling, ett aktivt slamsteg samt en efterföljande våtmark. Slammet hygieniseras i en våtkompost och avvattnas i en vassbädd. Avrinningen ska vara fosforrik och användas för kombinerad gödsling och bevattning. Avvattnat slam ska användas som jordförbättringsmedel. Syftet med reningsverket är att få till ett lokalt kretslopp av organiskt hushållsavfall, och minskade avfallstransporter.

    Hammarö kommun ligger i Värmland vid Klarälvens mynning i Vänern. Utanför centralorten finns spridd permanent bebyggelse och omfattande fritidsbebyggelse utan anslutning till kommunalt vatten och avlopp. Marken karakteriseras av berg i dagen, tunn jordmån, och lera

    eller tät morän. Infiltration som reningsmetod har därmed dåliga förutsättningar. Med nuvarande enskilda avloppslösningar föreligger stora risker för läckage av näringsämnen till Vänern. Dåligt renat avloppsvatten utgör också en risk för vattenkvaliteten i enskilda

    brunnar. Syftet med rapporten är att före byggandet av Hammarös nya reningsverk klargöra storleken på flöden av näringsämnen och mängden transporter av hushållsavfall i området. Detta för att etablera den nollpunkt som behövs för att senare kunna bedöma vilka

    förbättringar som uppnåtts med det nya reningskonceptet. Från hushåll på östra Hammarö går

    930 kg kväve och 120 kg fosfor till det nuvarande reningsverket på Vidön, medan 2100 kg kväve och 370 kg fosfor läcker ut till omgivningen. Transportarbetet på Hammarö för sopor, latrin, slam och tankinnehåll är ca 21000 km per år. Detta fördelar sig på sopor 3900 km/år, latrin 480 km/år, slam 5700 km/år och tankinnehåll 11000 km/år

  • 38.
    Granström, Karin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Wood processing as a source of terpene emissions compared to natural sources2007In: / [ed] C.A. BREBBIA, UK: WIT Press , 2007Conference paper (Refereed)
  • 39.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Berghel, Jonas
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Steam Drying of Sawdust for Pellets Production2003Conference paper (Other (popular science, discussion, etc.))
  • 40.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Hagelqvist, Alina
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Sandberg, Maria
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Efficiency of techniques for purification of condensate from wood dryers2013Conference paper (Refereed)
  • 41.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Javeed, Asif
    Emissions from bed drying of sawdust for pellets production2013Conference paper (Refereed)
  • 42.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Larsson, Amanda
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Biogas from algae farmed in pulp and paper mill wastewater2015In: GGROS 2015, Örnsköldsvik, Sweden, 23-25 March 2015., 2015Conference paper (Refereed)
    Abstract [en]

    Pulp and paper mills have waste streams that can be used for the farming of algae. The mills wastewater treatment provides heat to the algae ponds and the flue gas provides carbon dioxide. A current project is aiming at producing oil, for biodiesel or lubricating oil, from mill-farmed algae. Ten pools have been constructed and seeded with different strains of algae. After harvest and separation of oil, there is a leftover algae pulp. The fate of this algae remnant is an important part in achieving economic and energy viability for the whole process.

    The purpose of this work was to study the potential to produce biogas from algae grown in pulp and paper mill wastewaters, for different algae strains and pond conditions, with differing degrees of oil separation before the anaerobic digestion stage. The methane potential of the various algae pulps was tested by anaerobic digestion batch assays under thermophilic conditions for 23 days. 

    Pre-treatment of substrate is sometimes done in order to reduce the necessary retention time of biogas production. One batch of algae was subjected to either thermal pre-treatment or NaOH or comminution, to assess the effect on these methods on methane production.

    Ammonia concentration and pH in the digestate was analyzed to monitor the anaerobic digestion process, and the algae pulp’s content of fat, protein and carbohydrates were analyzed to characterize the substrate. In addition, the dewaterability of algae and of algae digestate was examined, as the dewaterability affects transport costs and possible use of the digestate.

    During the first year of operation, the algae in the range pond produced 186 ml CH4/g VS. The pre-treatments did not significantly affect the methane potential. The second year of operation saw more adapted strains of algae which are expected to produce somewhat different results [data from these experiments can be presented at the conference].  

    The research is of importance for the development of the biogas market as new substrates are needed to reach the volumes that are necessary to achieve economic viability for biogas plants. By characterizing the algae, it should be easier to see which role they are suitable to play in a co-digestion mix. Furthermore, the production of bio-oil and biogas together benefit the bioenergy system as a whole.

  • 43.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Montelius, Josefine
    Pre-Treatment To Enhance Biogas Yield from Pulp and Paper Mill Sludge2014In: Journal of Chemistry and Chemical Engineering, ISSN 1934-7375, E-ISSN 1934-7383, no 8, p. 825-833Article in journal (Refereed)
    Abstract [en]

    The purpose of this work was to study the potential to enhance biogas production from pulp and paper mill sludge by the use of thermal pre-treatment in combination with chemical pre-treatment. Biogas from waste is a renewable fuel with very low emissions during combustion. To further reduce the use of fossil fuels, more biogas substrates are necessary. Pulp and paper mill sludge is a large untapped reservoir of potential biogas. Pulp and paper mill sludge was collected from a mill that produces both pulp and paper and has a modified waste activated sludge system as part of its wastewater treatment. Pre-treatments were chosen heat (70 oC or 140 oC) combined with either acid (pH 2 or pH 4) or base (pH 9 or pH 11, obtained with Ca(OH)2 or NaOH). Biogas potential was tested by anaerobic digestion batch assays under mesophilic conditions. All pre-treatments were tested in six replicates. Biogas volume was measured with a gas-tight syringe and methane concentration was measured with a gas chromatograph. The methane yield from sludge subjected to thermal pre-treatment at 70 oC did not differ from the untreated sludge, but thermal pre-treatment at 140 oC had a positive effect. Within the 70 oC thermal pre-treatment group, the pH 2 acid was the most successful chemical pre-treatment, and Ca(OH)2 pH 9 had the least effect with no measurable improvement in methane yield. For the 140 oC thermal pre-treatment group, acid and NaOH impacted methane production negatively, while the Ca(OH)2-treated sludge did not differ from sludge with no chemical pre-treatment. In conclusion, thermal pre-treatment at 70 oC showed no effect, whereas, pre-treatment at 140 oC improved methane yield with 170%, and for this sludge additional, chemical pre-treatments are unnecessary.

  • 44.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Montelius, Josefine
    Pre-treatment to enhance biogas yield from pulp and paper mill sludge2014In: 2nd International conference on environmental science and technology ICOEST’2014, Side, Turkey, 14–17 May, 2014., 2014Conference paper (Refereed)
  • 45.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Thermic degradation of hardwood during drying as a function of processing parameters2008Conference paper (Other (popular science, discussion, etc.))
  • 46.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Volatile organic compounds emitted from hardwood drying as a function of processing parameters2008In: International Journal of Environmental Science and Technology, ISSN 1735-1472, E-ISSN 1735-2630, Vol. 5, no 2, p. 141-148Article in journal (Refereed)
    Abstract [en]

    During the drying of wood, volatile organic compounds are emitted. These emissions contribute, in the presence of nitrogen oxides and sunlight, to the formation of ground level ozone and other harmful photo-oxidants. Emissions of volatile organic compounds from the drying of birch sawdust in a spouted bed were analyzed with a flame ionization detector by flame ionization detector and with a gas chromatograph-mass pectrometer GC MS. A D-optimal model of the volatile organic compounds emissions showed that the emissions increased exponentially with decreasing sawdust moisture content and that the final sawdust moisture content was influencinge emissions about twice as much as the inlet drying medium temperature and the month of logging. At inlet temperatures of 140-170 °C, the emissions increased steeply when the moisture content of the sawdust reached 10 %, whereas an inlet temperature of 200 °C caused a surge of thermal degradation products at 15 % moisture content. The results of this study should help to reduce the emissions of volatile hydrocarbons during the drying of hardwood sawdust and wood chips

  • 47.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Samson-Akpan, Enobong
    Hagelqvist, Alina
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Sustainable energy from pulp and paper mill sludge by co-digestion with municipal sludge under thermophilic conditions2014In: World bioenergy 2014, Jönköping, Sweden, 3-5 June 2014., 2014Conference paper (Other academic)
  • 48.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013). Karlstad Univ, Dept Engn & Chem Sci, SE-65188 Karlstad, Sweden..
    Sandberg, Maria
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013). Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Karlstad Univ, Dept Engn & Chem Sci, SE-65188 Karlstad, Sweden..
    Characterization of Wood-Dryer Condensate with Assessment of Toxicity to Microorganisms2017In: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 143, no 7, article id 04017019Article in journal (Refereed)
    Abstract [en]

    Drying of wood causes airborne emissions that can be reduced by recirculating all or part of the drying medium. This favors both emission control and energy efficiency, but results in a condensate that contains significant amounts of organic compounds. Drying operations have been requested by municipal regulatory bodies to clean the condensate before release. The industry has tested biological treatment of condensate from biomass dryers, but maintaining the viability of microorganisms has been a challenge. In this study, the effect of drying gas temperature and the final wood moisture content on the chemical composition and acute toxicity of the condensate was tested. Results showed that whereas the condensate from wood drying was extremely toxic to Vibrio fischeri employed in Microtox assays, the undefined mixed culture present in biosludge from a pulp and paper mill treatment plant were considerably less affected. (C) 2017 American Society of Civil Engineers.

  • 49.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Sandberg, Maria
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Hur påverkar undervisning om hållbar utveckling studenterna?2009In: Kapet, ISSN 1653-4743, Vol. 1, no 1, p. 37-51Article in journal (Other academic)
    Abstract [sv]

    Hållbar utveckling har integrerats i kurserna Miljökemi och Reningsteknik i högskoleingenjörsprogrammet Energi- och miljöteknik vid Karlstads universitet. Syftet med denna undersökning var att analysera studenternas kännedom om, förståelse av och attityd till hållbar utveckling, samt att se om studenterna anser att de i sin kommande yrkesroll som ingenjörer kan bidra till en hållbar samhällsutveckling.

    Enkäter användes för att mäta studenternas kunskap om hållbar utveckling, attityd till hållbar utveckling och relaterade frågeställningar, samt deras uppfattning om framtiden och sin egen roll. Studenternas förståelse av begreppet hållbar utveckling undersöktes genom analys av argumentationen vid debatter.

    Resultatet blev att kännedomen om begreppet hållbar utveckling ökade under kursernas gång, och studenterna visade prov på att ha insikter i såväl ekologisk som ekonomisk och social hållbarhet. Studenternas attityder visade på ett stort stöd för en hållbar samhällsutveckling och en hög medvetenhet om miljöproblemen. Signifikanta skillnader mellan studenter som läste Miljökemi respektive Reningsteknik var att de som läste Miljökemi hade betydligt större förkunskaper, samt att de efter kursen var mer skeptiska till bibehållen hög ekonomisk tillväxt med negativa effekter på miljön. Studenternas uppfattning om framtiden är långt ifrån enhetlig; positivt var att mätningen inte gav höga utslag vare sig för alternativet ekologisk och ekonomisk kollaps eller för alternativet att det behövs auktoritärt ledarskap. En överväldigande majoritet av studenterna ser möjligheter att efter examen, i sitt yrke, bidra till en hållbar utveckling av samhället.

  • 50.
    Granström, Karin
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Williams, Helen
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Berghel, Jonas
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Frodeson, Stefan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Sandberg, Maria
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Ståhl, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    The importance of a holistic perspective when investigating agricultural products as additives in sustainable pellets development2012Conference paper (Refereed)
12 1 - 50 of 65
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