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  • 201.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Critique of selected peer-reviewed publications on applied social life cycle assessment: Focus on cases from developing countries2019In: Clean Technologies and Environmental Policy, ISSN 1618-954X, E-ISSN 1618-9558, Vol. 21, no 2, p. 413-430Article in journal (Refereed)
    Abstract [en]

    The social aspect of sustainable and ‘clean’ production/manufacturing technologies is researched and understood by means of Social Life Cycle Assessment (SLCA), a Life Cycle Sustainability Assessment (LCSA) tool, which is still in its infancy. In this paper, a search for all peer-reviewed publications on applied Social LCA, which have appeared in scientific journals, between O’Brien et al (1996) and the latest one at the time of writing (April 2018), was carried out, using Scopus as the repository and using “S-LCA” OR “SLCA” OR “Social LCA” OR “Social Life Cycle Assessment” as search-phrases in title, abstract and keywords of publications, separately.  Overall, 213 publications were unearthed, and the trend shows that there has been a near-exponential increase over time. A little over 55% of these publications – 121 to be precise - were applications of S-LCA – often in combination with environmental-LCA and life cycle costing analysis, in an LCSA. This paper discusses the contributions of a selected subset of these 121 publications to the body of S-LCA knowledge, with the focus being restricted to applications in developing and transition economies of the world, on the premise that there is a more urgent need to understand social aspects of production and manufacturing in these parts of the world.  A SWOT analysis of S-LCA has been carried out towards the end. There is a consensus among many researchers that while LCC and E-LCA have matured a lot over time, S-LCA, the newest of the trio, is evolving slowly to become a harmonised tool which can serve as an effective complement to the aforesaid two, in life cycle sustainability assessments of products and processes in industry.         

  • 202.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Environmental Life-Cycle Analysis: A primer2016 (ed. First)Book (Refereed)
    Abstract [en]

    This little book is a primer. The target readership here is not necessarily only for engineers, but also for those studying to be lawyers, political scientists, administrators, business managers, etc. Lucid language, analogies and cartoons help to impress upon readers that environmental-LCA is not rocket-science.

    The reader is taken through the steps to be assiduously followed while performing an E-LCA. You understand the importance of defining the goal and the scope of your analysis before starting, and realise that E-LCA is data-intensive. Also covered are topics like attributional/consequential LCA, rebound effect and problem shifting, and allocation of environmental impacts. Attempting the exercises which appear at the end of every chapter will enable the reader to gain in confidence. As Prof Arun Kansal says in the Foreword to the book, ‘It explains the basic philosophy of LCA and argues, by providing examples, in its favour as a standard method for environmental decision-making.’ Dr Geoffrey Guest, in his Afterword, refers to the book as a ‘unique, light-hearted though philosophically-deep introductory piece on E-LCA.’

     

  • 203.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Environmental Life-cycle Analysis as a tool for sustainability studies: A complete learning experience.2019In: Problemy Ekorozwoju, ISSN 1895-6912, E-ISSN 2080-1971, Vol. 14, no 1, p. 79-85Article in journal (Refereed)
  • 204.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Industrial ecology tools as decision-making aids for sustainable phosphorus recovery: A methodology paper   Industriell-ekologi verktyg som beslutsstöd för hållbar fosfor återvinning:  en metod-artikel2018In: Vatten, ISSN 0042-2886, Vol. 74, no 3, p. 107-121Article in journal (Other academic)
    Abstract [en]

    India, being the second largest importer, and the largest consumer of phosphate fertilisers in the world, needs to focus on securing its supplies not merely by providing subsidies to importers but also focusing on recovery and recycling of phosphorus from waste streams. In the process, the country can avail of concomitant benefits like wastewater reclamation and bio-energy generation, and improve the lot of the millions of farmers in the country. In this paper the authors have outlined a methodology based on industrial ecology tools – MFA (SFA), E-LCA, LCC and S-LCA - which they intend to adopt in the near-term to study, analyse and model the status quo and proposed interventions, from a sustainability perspective, which will become indispensable in the not-too-distant future for the country. The literature review which has been segmented on the basis of the application of the different tools to the study and analysis of resource recovery from wastewater, provides insights into what has been done thus far, and prepares the bedrock for a more detailed analysis.  

     

  • 205.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Life cycle costing: A primer2019 (ed. 1)Book (Refereed)
  • 206.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Overhauling Higher Education by Factoring Sustainability into University Curricula: Discussion Based on a Survey2016In: Metamorphosis of Architectural Education in (Post) Transitional Context / [ed] Mladen Burazor, Markus Schwai, Nermina Zagora, Senka Ibrišimbegović,, Sarajevo: University of Sarajevo , 2016, p. 101-115Chapter in book (Refereed)
  • 207.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Pinch analysis, as a technique for optimising resource utilisation and promoting environmental sustainability: A review of recent case studies from the developing world and transition economies2019In: Resources Environment and Information Engineering, ISSN 2661-3131, Vol. 1, no 1, p. 1-17Article in journal (Refereed)
    Abstract [en]

    Pinch analysis, as a technique to optimise the utilisation of resources, traces its beginnings to the 1970s in Switzerland and the UK – ETH Zurich and Leeds University to be more precise. Over four decades down the line, this methodology has entrenched itself in research circles around the world. While the technique was developed, to begin with, for energy (heat) recovery, it has since then expanded to embrace several other fields, and enabled optimisation of resource utilisation in general. The motive behind this article is to perform a focused, selective review of recent case studies from the developing world and transition economies, having ‘pinch analysis’ in their titles and thereby as their ‘core, crux and gist’, during the period 2008-2018. The resources focused on, include heat energy, electrical energy, water, solid waste, money, time, land (surface area), storage space (volume), human resources, mass of resources in general and hydrogen, while a handful of publications have their focus on carbon dioxide (greenhouse gases in general) emissions. Multi-dimensional pinch analysis promises to be an effective tool for sustainability analysis in the years to come; most importantly in the developing world where social well-being and economic development are priorities in the years ahead, and they ought to be attained by a simultaneous truncation of the environmental footprint, in other words, an optimisation of resource utilisation as well as adverse environmental impacts. In other words, the focus ought to be on sustainable production (efficiency) and consumption (sufficiency). 

  • 208.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Recovery of different types of resources from wastewater – A structured review.2018In: Vatten, ISSN 0042-2886, Vol. 74, no 2, p. 1-18Article in journal (Other (popular science, discussion, etc.))
    Abstract [en]

    As the population of the world increases, and economies continue to develop, energy, water, materials of different types, and nutrients for food production will be needed in ever-increasing amounts. The water-energy nexus is well-understood in research circles, but one could modify this paradigm to water-nutrients/materials-energy nexus in order to incorporate recovery of substances that can be recirculated to the anthroposphere. ‘Resources’ would thus include both energy and materials (elements, compounds and mixtures – both organic and inorganic). Research in, and implementation of, recovery of different types of resources – material and energy - from wastewater (municipal, agricultural and industrial) has been going on for quite some time now. It will not be wrong to say that the imperativeness and importance of research in this field has been earnestly appreciated by academia, industry, utilities and governments alike in many parts of the world, over the last decade. This paper is a literature review of selected publications from the period 2010-2018, from a wide range of journals, focusing on resource recovery from wastewater. The selected publications originate from 44 different countries (in six continents) of the world.

  • 209.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Social LCA - An introduction: The What, the How and the Why2019Book (Refereed)
  • 210.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Water for All and other poems2015Book (Other (popular science, discussion, etc.))
  • 211.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Water pinch analysis: a review of recent peer-reviewed publications2018In: Vatten, ISSN 0042-2886, no 3, p. 147-152Article in journal (Other academic)
    Abstract [en]

    As the population of the world increases, the demand for resources of different types will also grow. Water is one such resource. Pinch analysis, as a technique to optimise the utilisation of resources, had its origin in heat recovery and thereby the optimisation of fuel usage in the 1970s during the oil crisis. Since then, it has expanded to encompass a vast swathe of resources – both material and otherwise. Water pinch analysis is one offshoot of this tool (the implementation is labelled as pinch technology). This short article is a focused and selective review of recent publications having ‘pinch analysis’ in their titles and as their ‘core and gist’, during the period 2008-2018, and having water pinch analysis as either the sole focus or one of the foci.

  • 212.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    We Came Before You and Other Poems2019Book (Other (popular science, discussion, etc.))
    Abstract [en]

    This manuscript of 31 self-illustrated poems having animals/birds/insects/reptiles as the leitmotif has manifold objectives. • Firstly, as the title suggests, it is to remind readers that we humans are effectively tenants in this world which is owned and let out to us by other living creatures – animals, birds etc. We thereby have our duties and responsibilities towards them and must be indebted to them for their kindness. Secondly, there is a lot we can learn from animals, birds and insects. Remember King Bruce and the spider which taught him a valuable lesson? And we have a host of animal similes – as brave as a lion, as busy as a bee, as free as a bird, as gentle as a lamb, as wise as an owl, and so on. Thirdly, while a lot of work is being done by dedicated individuals and organisations for animal/bird welfare, this is a product of the inspiration which all these people have provided – to contribute a little in my own way. All the sketches have been made by the poet himself

  • 213.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Where science fails, outdated religion provides clues2017In: Problemy Ekorozwoju, ISSN 1895-6912, E-ISSN 2080-1971, Vol. 12, no 2, p. 119-122Article in journal (Refereed)
    Abstract [en]

    Solutions to challenges, and answers to questions are often to be found in what he normally overlook, downplay and reject and deny. The Ask and it will be given to you; seek and you will find; knock and the door will be opened to you of the Holy Bible refers to seeking there where one normally would not expect to find anything. The caste-system which prevailed in ancient Hindu society (and still does, though not as prominently as before) does have some hidden lessons for the modern Hindu (in India or in the wider Indian diaspora), which could be very valuable for sustainable development.

  • 214.
    Govindarajan, Venkatesh
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Nyflött, Åsa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Bonnerup, Chris
    Stora Enso.
    Lestelius, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    An economic-environmental analysis of selected barrier coating materials used in packaging food products: A Swedish case study2018In: Environment, Development and Sustainability, ISSN 1387-585X, E-ISSN 1573-2975, Vol. 20, no 4, p. 1483-1497Article in journal (Refereed)
    Abstract [en]

    The purpose of a barrier coating in food packaging is primarily to increase the shelf life of the foodstuff contained within the packaging, preserve its colour, odour, taste and quality, and thereby reduce food wastage (both at retail outlets and households). While most publications hitherto have compared packaging and barrier-coating materials on the basis of their environmental impacts alone, this paper adopts a more holistic approach by factoring in the economic aspect as well. Four barrier material alternatives—starch, polyethylene, EVOH + kaolin and latex + kaolin are analysed. Two well-defined end-of-life handling scenarios, relevant to Sweden, are: one in which everything except starch is recycled, with starch being composted, and the other in which everything is incinerated. Among the several environmental impact categories which can be analysed, this paper considers only global warming. Two approaches are tested to combine the economic and environmental aspects—normalisation, weighting and aggregating on the one hand, and using the carbon tax to internalise the externality caused by GHG emissions on the other. For the set of weighting factors obtained thanks to a survey conducted by the authors (40.6% for environmental and 59.4% for economic), starch emerges as the most sustainable alternative, followed by polyethylene for both the end-of-life handling scenarios. This tallies with the result obtained by using the carbon tax for internalisation of the externality. The case study, methodology and results presented in this paper, will hopefully be a springboard for more detailed studies of this nature, under the umbrella of sustainability.

  • 215.
    Granbom, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Nitritomvandling vid Skebäck avloppsreningsverk2016Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    On several occasions fish died in Hjälmaren due to, among other things, elevated nitrite levels in the lake. A contributing factor turned out to be the high nitrite content that leaves the wastewater treatment plant Skebäck, located in Örebro. The wastewater is purified from nitrogen through nitrification and denitrification where nitrite occurs as an intermediate in several reaction steps. The report contains theory round the formation of nitrite and the results from samplings where nitrite concentration was determined. The objective was to increase nitrite conversion and thereby decrease the content of nitrite in the effluent water, by studying the increase of nitrite.   Samplings started in March and no changes in the process where made, the first samples were analyzed to determine where the nitrite accumulation occurred. The samplings were taken in the intermittently aerated basin, wish includes a aerated period and a nonaerated period.   The initial samples showed that nitrite accumulates when there is oxygen in the basin. The content of nitrite decreases when there is no oxygen in the water. The ammonium limits were changed in one basin because it was suspected that the bacteria were becoming stressed by the intermittent aerated start-stop process. This resulted in a longer aerated period for the nitrified bacteria to grow and due to the change it was expected that the bacteria would thrive. This proved insufficient for nitrite oxidation to take place, but the concentration of nitrite at this time was at least lower.  These changes did not show any reduction in the nitrite concentration. Suggestions for future work are addition of an extern carbon source and optimizing the aeration. 

  • 216.
    Granstrom, Karin
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Javeed, Atif
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    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.

  • 217.
    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

  • 218.
    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)
  • 219.
    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.

  • 220.
    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)
  • 221.
    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.

  • 222.
    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.

  • 223.
    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)
  • 224.
    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)
  • 225.
    Granström, Karin
    et al.
    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).
    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.

  • 226.
    Guo, Sanchuan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre.
    Heijnesson-Hulten, Anette
    Basta, Jiri
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Wang, Qianqian
    Germgård, Ulf
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Optimum Bamboo Kraft Cooking - The Influence of The Cooking Conditions on The Pulp and Fibre Properties2010In: O Papel 0031-1057, Vol. 71, no 7, p. 63-75Article in journal (Refereed)
  • 227.
    Gustavsson, Christer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Added value from biomass by broader utilization of fuels and CHP plants2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The present work, where additional value-creating processes in existing combined heat and power (CHP) structures have been examined, is motivated by a political- and consumer-driven strive towards a bioeconomy and a stagnation for the existing business models in large parts of the CHP sector.

    The research is based on cases where the integration of flash pyrolysis for co-production of bio-oil, co-gasification for production of fuel gas and synthetic biofuels as well as leaching of extractable fuel components in existing CHP plants have been simulated. In particular, this work has focused on the CHP plants that utilize boilers of fluidized bed (FB) type, where the concept of coupling a separate FB reactor to the FB of the boiler forms an important basis for the analyses. In such dual fluidized bed (DFB) technology, heat is transferred from the boiler to the new rector that is operating with other fluidization media than air, thereby enabling other thermochemical processes than combustion to take place. The result of this work shows that broader operations at existing CHP plants have the potential to enable production of significant volumes of chemicals and/or fuels with high efficiency, while maintaining heat supply to external customers.

    Based on the insight that the technical preconditions for a broader operation are favourable, the motivation and ability among the incumbents in the Swedish CHP sector to participate in a transition of their operation towards a biorefinery was examined. The result of this assessment showed that the incumbents believe that a broader operation can create significant values for their own operations, the society and the environment, but that they lack both a strong motivation as well as important abilities to move into the new technological fields.

    If the concepts of broader production are widely implemented in the Swedish FB based CHP sector, this can substantially contribute in the transition towards a bioeconomy.

  • 228.
    Gustavsson, Christer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    MANUSCRIPT: The Role of Incumbents in the Transition towards a Bioeconomy: Motivation and Abilities of the Combined Heat and Power SectorManuscript (preprint) (Other academic)
  • 229.
    Gustavsson, Christer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Hulteberg, Christian
    Lund University.
    Co-production of gasification based biofuels in existing combined heat and power plants - Analysis of production capacity and integration potential2016In: Energy Journal, ISSN 0195-6574, E-ISSN 1944-9089, Vol. 111, no September, p. 830-840Article in journal (Refereed)
    Abstract [en]

    Solid fuel fired fluidized bed (FB) boilers are common in combined heat and power (CHP) plants in district heating- and process industry. In this study, utilization of such FB boilers for production of syngas in dual fluidized bed gasifiers and subsequent catalytic biofuel production to substitute natural gas (SNG), methanol (MeOH) and Fischer-Tropsch fuel (FT) has been examined. Based on the hypothesis that waste-heat and tail gas from the biofuel processes can be utilized in the CHP plant, process configurations aiming for operationally robustness and low investment cost rather than maximum stand-alone efficiency have been explored and implemented in actual industrial cases and over the full operating range of the boilers. The results of the study show that significant improvements of overall efficiency can be achieved by integration of the biofuel processes in the CHP plants and that a relatively high biofuel production capacity can be achieved. SNG showed the highest obtainable efficiency and production capacity of the studied biofuels, whereas the FT process showed largest increase in terms of efficiency when integrated in the CHP plant, compared to its stand-alone efficiency.

  • 230.
    Gustavsson, Christer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Nilsson, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Addition/Correction: Co-production of pyrolysis oil in district heating plants: Systems analysis of dual fluidized-bed pyrolysis with sequential vapor condensation (Energy and Fuels (2013) 27:9 (5313?5319) DOI: 10.1021/ef401143v)2013In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 27, no 10, p. 6333-6333Article in journal (Refereed)
  • 231.
    Gustavsson, Christer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Nilsson, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Co-production of pyrolysis oil in district heating plants: Systems analysis of dual fluidized-bed pyrolysis with sequential vapor condensation2013In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 27, no 9, p. 5313-5319Article in journal (Refereed)
    Abstract [en]

    Flash pyrolysis of biomass yields a liquid applicable as a fuel oil substitute and as a basis for production of chemicals and fuels. Biomass, being a renewable resource, is foreseen to be in increasing demand. An increased usage may lead to scarcity of biomass and emphasizes the need for high-efficiency conversion processes. In this study, the efficiency and capacity aspects of an integration of pyrolysis oil production with a district heating plant by means of dual fluidized-bed technology has been modeled. Further, fractional condensation of the pyrolysis vapors has been applied, enabling part of the condensation energy to be recovered. The concept shows potential for significant pyrolysis oil production while keeping the delivered power and heat constant. The use of excess heat from the pyrolysis production in the district heating net results in a 10% higher overall efficiency than production without heat supply to the district heating net.

  • 232.
    Gustavsson, Christer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Nilsson, Lars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Renström, Roger
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Syngas as an Additional Energy Carrier in the Pulp and Paper Industry: A Mill-Wide System Analysis of a Combined Drying Concept, Utilizing On-Site Generated Gas and Steam2014In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 28, no 9, p. 5841-5848Article in journal (Refereed)
    Abstract [en]

    Large amounts of thermal energy are required for different unit operations in the pulp and paper industry. Typically, this energy is distributed by means of steam. In this study, introduction of in-situ-generated syngas as an energy carrier in parallel to the predominant steam has been investigated. The examined systems use dual fluidized-bed gasification integrated with a solid fuel boiler of a paper mill together with impingement drying in combination with cylinder drying, a concept enabling higher specific drying rates. The studied systems exhibit reduced overall energy use when compared to the present situation with conventional steam-heated cylinder drying. Cold tar cleaning by condensation/absorption and firing of the syngas in a gas turbine followed by utilization of the exhaust gases for drying are interesting options because this results in reduced biomass consumption with maintained power production.

  • 233.
    Hagelqvist, Alina
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Batchwise mesophilic anaerobic co-digestion of secondary sludge from pulp and paper industry and municipal sewage sludge2013In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 33, no 4, p. 820-824Article in journal (Refereed)
    Abstract [en]

    Residues from forest-industry wastewater-treatment systems are treated as waste at many pulp and paper mills. These organic substances have previously been shown to have potential for production of large quantities of biogas. There is concern, however, that the process would require expensive equipment because of the slow degradation of these substances. Pure non-fibrous sludge from forest industry showed lower specific methane production during mesophilic digestion for 19 days, 53 ± 26 Nml/g of volatile solids as compared to municipal sewage sludge, 84 ± 24 Nml/g of volatile solids. This paper explores the possibility of using anaerobic co-digestion with municipal sewage sludge to enhance the potential of methane production from secondary sludge from a pulp and paper mill. It was seen in a batch anaerobicdigestion operation of 19 days that the specific methane production remained largely the same for municipal sewage sludge when up to 50% of the volatile solids were replaced with forest-industry secondary sludge. It was also shown that the solid residue from anaerobic digestion of the forest-industry sludge should be of suitable quality to use for improving soil quality on lands that are not used for food production.

  • 234.
    Hagelqvist, Alina
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Sludge from pulp and paper mills for biogas production: Strategies to improve energy performance in wastewater treatment and sludge management2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The production of pulp and paper is associated with the generation of large quantities of wastewater that has to be purified to avoid severe pollution of the environment. Wastewater purification in pulp and paper mills combines sedimentation, biological treatment, chemical precipitation, flotation and anaerobic treatment, and the specific combination of techniques is determined by the local conditions. Wastewater treatment generates large volumes of sludge that after dewatering can be incinerated and thus used for bio-energy production. Sludge is currently viewed as biofuel of poor quality due to its high water content, and some mills treat it solely as a disposal problem.

    Two strategies have been identified as feasible options to improve the energy efficiency of sludge management. One is drying using multi-effect evaporation followed by incineration. The other is anaerobic digestion of the wet sludge to produce methane.

    This thesis explores the energy balances of sludge management strategies in pulp and paper mills with special focus on anaerobic digestion. The first part consists of a system analysis, used to evaluate some wastewater treatment processes and sludge management, and the second part of empirical studies of anaerobic digestion of pulp and paper mill sludge. It was shown that the use of energy for aeration in aerobic biological treatment should be kept to the minimum required for acceptable quality of the processed water. Additional aeration for reduction of the generated sludge will only result in reduced energy generation in a subsequent methane generation stage. In the second part of the thesis, it is shown that anaerobic digestion is a feasible option for sludge management as it leads to production of high value biogas. Co-digestion with grass silage, cow/pig manure or municipal sewage sludge should then be used to counteract the low nitrogen content of pulp and paper mill sludge.

  • 235.
    Hagelqvist, Alina
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Co-digestion of manure with grass silage and pulp and paper mill sludge using nutrient additions2016In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 37, no 16, p. 2113-2123Article in journal (Refereed)
    Abstract [en]

    The purpose of this research is to evaluate how methane production is affected by the co-digestion of pig and dairy manure with grass silage and pulp and paper mill sludge at mesophilic conditions, and to assess whether methane production is affected by other factors than the now known ones, i.e., nutrient deficiency, low buffering capacity, inadequate dilution, and an insufficient activity and amount of microorganism culture. The season of grass silage and manure collection proved to be an important, previously unreported, factor affecting short-term (20 days) methane production.

  • 236.
    Hagelqvist, Alina
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Mehmood, Danish
    Improving the biogas potential of pulp and paper mills while decreasing the electricity demand for wastewater treatment2013Conference paper (Refereed)
    Abstract [en]

    Sludge formed during the necessary wastewater treatment in forest industry is currently considered to be a waste stream; rich in organic substances and poor in macronutrients, especially phosphorus and nitrogen. Previous work has shown that excessive use of electricity for aeration in wastewater treatment counteracts the potential for energy recovery in the subsequent sludge handling system, as prolonged aeration is used to degrade organic matter. This work shows that chemical oxygen demand of wastewater was not reduced further when the solids retention time was increased in aerated wastewater treatment from 2 days to 10 and 20 days respectively. The results presented here strengthen the previous conclusion that energy should only be used for sufficient effluent treatment, not for sludge reduction. A decreased need for aeration can be achieved by shortening the sludge retention time both by a decreased oxygen requirement and increased aeration efficiency. Shortened sludge retention time was shown here to increase production of biosludge as well as to increase the specific methane potential of biosludge. The results show that sludge with shorter solids retention time in the aerated treatment step gives more production of methane gas compared to sludge with longer solids retention time.

  • 237.
    Hagelqvist, Alina
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Murto, Marika
    Department of Biotechnology, Lund University.
    Anaerobic self-degradation of pig and dairy manure using co-digestion with grass silage and pulp and paper mill sludge to shorten the start-up time2013In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to find a way to shorten the start-up time of a pig and dairy manure based anaerobic digester without addition of external inoculum. Self-degradation was tested to simulate the setting of many sites where the use of external seed culture is not feasible because of the large distance to a nearest location where appropriate material can be collected. In this case study, co-digestion of pig and dairy manure with grass silage and pulp and paper mill sludge was tested using different compositions. The results showed that one tertiary mixture of 17 per cent of piggery manure, 17 per cent of dairy manure and 66 per cent of pulp and paper mill sludge resulted in a considerably shorter start-up time (about 15 days) as well as in a higher methane yield (120 ml CH4/g VS added after 44 days of batch operation) as compared to other mixtures tested. This mixture composition is recommended to start-up the full-scale process. Concentrations of ammonium of 0.4 g/l combined with slowly degradable material favoured a rapid start and efficient digestion.

  • 238. Haghighi, B.
    et al.
    Gorton, L.
    Ruzgas, T.
    Jönsson, Leif J
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre.
    Characterization of graphite electrodes modified with laccase from Trametes versicolor and their use for bioelectrochemical monitoring of phenolic compounds in flow injection analysis2003In: Anal. Chim. Acta. (2003) 487, 3-14Article in journal (Refereed)
  • 239. Hallberg Hofstrand, Erik
    et al.
    Lestelius, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science.
    The Influence of Printing Forms Mechanical Properties on Flexographic Post-Printing2004Conference paper (Other (popular science, discussion, etc.))
  • 240. Hallberg Hofstrand, Erik
    et al.
    Lestelius, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science.
    Rättö, Peter
    Dynamic Measurements of Nip Force Variations during Post-Printing of Corrugated Board2006In: Nordic Pulp & Paper Research Journal, 21(1), 111-114 (2006)Article in journal (Refereed)
    Abstract [en]

    A method has been developed in order to measure nip force variations during flexographic post-printing of corrugated board. This method can be used to study the influence of the nip mechanics on the final print quality

  • 241. Hallberg Hofstrand, Erik
    et al.
    Lestelius, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science.
    Rättö, Peter
    Thuvander, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Odeberg Glasenapp, A.
    Evaluation of Pressure Variations Generated During Flexographic Post-Print of Corrugated Board and Effects of Mechanical Properties of Printing Forms on Printed Banding2004Conference paper (Other (popular science, discussion, etc.))
  • 242. Hallberg Hofstrand, Erik
    et al.
    Lestelius, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science.
    Rättö, Peter
    Thuvander, Fredrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science. Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Engineering.
    Odeberg Glasenapp, A
    Flexo Print of Corrugated Board: Mechanical Aspects of the Plate and Plate Mounting Materials2005In: TAGA Journal, vol.2,pp.16-28Article in journal (Refereed)
  • 243. Hallberg Hofstrand, Erik
    et al.
    Odeberg Glasenapp, A.
    Lestelius, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science.
    Quantification of Banding on Printed Corrugated Board using Spatial Frequency Analysis2005In: Packaging Technology and Science,vol 18,no.2,pp.85-95, 2005Article in journal (Refereed)
  • 244.
    Hallbäck, Nils
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Korin, Christer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Barbier, Christophe
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Nygårds, Mikael
    KTH.
    Finite Element Analysis of Hot Melt Adhesive Joints in Carton Board2014In: Packaging technology & science, ISSN 0894-3214, E-ISSN 1099-1522, Vol. 27, no 9, p. 701-712Article in journal (Refereed)
  • 245.
    Hamarashid, Ramyar
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Mojab, Sayed Reza
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Effektivisering av produktionssystem: En fallstudie på Derome Plusshus2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Abstract This work will be carried out in cooperation with Derome Plusshus which has a factory in Kristinehamn with approximately 40 employees and produces modular home. On behalf of the company, we have taken on the challenge of identifying improvement opportunities in the production process in the workshop, where through consultation with the company, it was decided that the focus should be on the module-line, which is the bottleneck in the production process. The aim of this work is to identify improvement opportunities that exist for the production process in the Assembly station, with a focus on the lead time. As well as providesuggestions on improvement measures will lead to an increase in production capacity, which is also the goal of the work. This will be achieved by eliminating non-value adding activities. This is a development which also contributes to a sustainable production system. In essence, the observation in the workplace, which served as the material for the work in which the latter were analyzed for a better understanding of the situation. It gave a refined material that is then analyzed based on theories lean production and 5S. It helped that the suggestions could be presented divided into share increased production capacity. The used theories at work complement each other as lean production, minimize wastage in production such as; over-production, inventory, over work, transport, wait, wrong & rework, movements and untapped creativity. Then lean production processes production supplemented it with 5S that minimize disruption to the production process. 5s consists of five key words that are logical and are based on each other, the five words reads; sort, systematize, sweep, standardize and ensure systematic review. The result was an increase in production capacity by about 25 percent, however, with the condition that all the improvement proposals, which are designed for the improvement opportunities that are recurring, is implemented. Where improvement proposals range from minor adjustments in the production process to the investment of new tools and machinery which means a cost to Derome Plusshus.

  • 246.
    Hammar, Mikael
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Strategier vid avveckling av vindkraftverk - en livscykelanalys: Miljöpåverkan för vindkraftverket Lucia af Boholmen från vaggan till graven2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    År 1995 investerade kooperativet Hammarövind i ett av de modernaste största vindkraftverken på marknaden, Wind World 3700 med effekten 500 kW.  Verket togs i drift den 13 december år 1995 ute på Boholmen i Hammarö därav namnet Lucia af Boholmen.  Nu 21 år senare börjar vindkraftverket nå sitt slut och när planer för avvecklingen av vindkraftverket börjar tas fram fanns det intresse inom kooperativet att veta vindkraftverkets miljöpåverkan från vaggan till graven, en livscykelanalys. Den undersökningen utförs i detta arbete.  

    En LCA undersöker en produkts miljöpåverkan från när råvaran utvinns, tillverkning av produkten, användning och till slut hur produkten behandlas efter att livslängden har tagit slut. LCA är inget nytt inom vindkraft utan det finns ett stort antal LCA gjorda både av äldre kW verk till modernare MW vindkraftverk. Det finns en god uppfattning kring LCA resultatet för vindkraftverk, att det enbart tar ett antal månader för verket att producera den mängd energi som går åt i konstruktionsfasen och driftfasen, att koldioxidekvivalentutsläppen ligger runt 20 g/kWh.  Sedan skiljer sig olika LCA ifrån varandra beroende på olika vindkraftverks effekter, geografiska aspekter, olika antagande som har gjorts och inkonsekventa data för att nämna några orsaker.

    Det har visats sig att dessa LCA har en brist i och med att avvecklingsfasen av vindkraftverken inte undersöks. Anledningen till detta är att det saknas erfarenhet och intresset för detta moment är lågt då storskalig nermontering av vindkraftverk inte förväntas påbörjas förrän om 10 år. Men om hållbara metoder för att ta hand om vindkraftverken inte undersöks och utvecklas kommer detta att bli ett stort problem i framtiden då avfallsmängderna förväntas öka lavinartat och vindkraftverken bild som en grön energikälla kan ta skada.

    Syftet med detta arbete är att utreda hur olika avvecklingsmetoder för vindkraftverket Lucia af Boholmen påverkar resultatet för LCA.  De olika avvecklingsmetoderna som undersöktes var återvinning, fortsatt produktion på samma plats och flytt till annat land för fortsatt produktion.

    Resultatet visade att utan avvecklingsfasen tar det lite mer än 14 månader för vindkraftverket att producera den mängd energi som går åt i konstruktion och driftfasen av vindkraftverket. Intensiteten för energi hamnade på 0,063 kWh/kWh och koldioxidekvivalentutsläppen 20,52 g/kWh.

    Återvinning av vindkraft ger en energivinst mellan 157 och 193 MWh beroende på hur vindkraftbladen behandlas och de koldioxidekvivalentutsläpp som undviks ligger mellan 57,5 och 59,4 ton. Om vindkraftverket renoveras och fortsätter producera på samma plats upp till 10 år kan intensiteten för energi sänkas till 0,0368 kWh/kWh en sänkning med 41 % och koldioxidekvivalent till 12,4 g/kWh en sänkning med 39 %. Dock är chansen att få en ekonomisk lönsamhet med dagens elpris väldigt låg. Om vindkraftverket flyttas till ett annat land där stödsystem ingår kan en ekonomisk lönsamhet uppnås samtidigt som en stor miljövinst erhålls.  

  • 247.
    Hansson, Björn
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Evaluation of Compression Testing and Compression Failure Modes of Paperboard: Video analysis of paperboard during short-span compression and the suitability of short- and long-span compression testing of paperboard2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The objectives of the thesis were to find the mechanisms that govern compression failures in paperboard and to find the link between manufacturing process and paperboard properties. The thesis also investigates two different test methods and evaluates how suitable they are for paperboard grades. The materials are several commercial board grades and a set of hand-formed dynamic sheets that are made to mimic the construction of commercial paperboard. The method consists of mounting a stereomicroscope on a short-span compression tester and recording the compression failure on video, long-span compression testing and standard properties testing. The observed failure modes of paperboard under compression were classified into four categories depending on the appearance of the failures. Initiation of failure takes place where the structure is weakest and fiber buckling happens after the initiation, which consists of breaking of fiber-fiber bonds or fiber wall delamination. The compression strength is correlated to density and operations and raw materials that increase the density also increases the compression strength. Short-span compression and Long-span compression are not suitable for testing all kinds of papers; the clamps in short-span give bulky specimens an initial geometrical shape that can affect the given value of compression strength. Long-span compression is only suitable for a limited range of papers, one problem with too thin papers are low wavelength buckling. 

  • 248.
    Hedenqvist, Mikael
    et al.
    Fibre and polymer technology, KTH Royal Institute of Technology, Stockholm, Sweden.
    Johansson, Eva
    Department of Plant Breeding, The Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Newson, William
    Department of Plant Breeding, The Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Gallstedt, Mikael
    Innventia AB, Stockholm, Sweden.
    Kuktaite, Ramune
    The Swedish University of Agricultural Scienc, Alnarp, Sweden.
    Ullsten, Henrik
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Ture, Hasan
    Faculty of Marine Sciences, Ordu University, Ordu, Turkey.
    Extrusion of protein plastics2017In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 253, article id 449Article in journal (Other academic)
  • 249.
    Heidkamp, Hannah
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    van Stam, Jan
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Carlsson, Gunilla
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Moons, Ellen
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering. Karlstad University, Faculty of Technology and Science, Materials Science.
    Rogowski, Rafal
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Morphology of PCBM and P3HT blends in films made by dip-coating on homogeneous and chemically patterned surfaces,2011Conference paper (Refereed)
  • 250.
    Heijnesson-Hulten, Anette
    et al.
    AkzoNobel, SE-44580 Bohus, Sweden..
    Guo, Sanchuan
    Karlstad University.
    Basta, Jiri
    AkzoNobel, SE-44580 Bohus, Sweden.
    Daniel, Geoffrey
    Swedish Univ Agr Sci, Dept Forest Prod Wood Sci, SE-75007 Uppsala, Sweden.
    Zhan, Huaiyu
    S China Univ Technol, State Key Lab P&P Engn, Guangzhou 510640, Guangdong, Peoples R China.
    Germgård, Ulf
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Impact of Drying on the Quality of Bamboo Kraft Pulps2013In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 8, no 1, p. 1245-1257Article in journal (Refereed)
    Abstract [en]

    This study investigates how drying affects the quality of bamboo kraft pulps. Two bamboo pulps, cooked to different kappa numbers (i.e. 10 and 26) and D(EOP)D bleached to approximately the same brightness, were used to examine the relationship between cooking, drying, refining, and pulp/fiber properties. Drying of the two pulps caused, as expected, a loss in tensile and burst strength while the tear index was improved. The bleached high kappa pulp required less energy to reach a certain Schopper Riegler value and exhibited greater strength properties than the low kappa number pulp. These differences were also maintained after drying. Results showed that the properties of the pulp before drying determined the final strength potential of the pulp after drying. Thus, kraft cooking of bamboo to high kappa number prior to bleaching gave pulps with improved response to refining and pulp strength properties, which in turn influenced the properties of the dried pulps.

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