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  • 151.
    Haas, Jan
    Karlstad University.
    Object-based fusion of ENVISAT ASAR and HJ-1B Optical Data for Urban Land Cover Mapping2011Other (Other academic)
  • 152.
    Haas, Jan
    KTH, Geoinformatik.
    Remote Sensing of Urbanization and Environmental Impacts2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis aims to establish analytical frameworks to map urban growth patterns with spaceborne remote sensing data and to evaluate environmental impacts through Landscape Metrics and Ecosystem Services. Urbanization patterns at regional scale were evaluated in China's largest urban agglomerations and at metropolitan scale in Shanghai, Stockholm and Beijing using medium resolution optical satellite data. High-resolution data was used to investigate changes in Shanghai’s urban core. The images were co-registered and mosaicked. Tasseled Cap transformations and texture features were used to increase class separabilities prior to pixel-based Random Forest and SVM classifications. Urban land cover in Shanghai and Beijing were derived through object-based SVM classification in KTH-SEG. After post-classification refinements, urbanization indices, Ecosystem Services and Landscape Metrics were used to quantify and characterize environmental impact. Urban growth was observed in all studies. China's urban agglomerations showed most prominent urbanization trends. Stockholm’s urban extent increased only little with minor environmental implications. On a regional/metropolitan scale, urban expansion progressed predominately at the expense of agriculture. Investigating urbanization patterns at higher detail revealed trends that counteracted negative urbanization effects in Shanghai's core and Beijing's urban-rural fringe. Beijing's growth resulted in Ecosystem Services losses through landscape structural changes, i.e. service area decreases, edge contamination or fragmentation. Methodological frameworks to characterize urbanization trends at different scales based on remotely sensed data were developed. For detailed urban analyses high-resolution data are recommended whereas medium-resolution data at metropolitan/regional scales is suggested. The Ecosystem Service concept was extended with Landscape Metrics to create a more differentiated picture of urbanization effects.​

  • 153.
    Haas, Jan
    KTH, Geodesi och geoinformatik.
    Remote Sensing of Urbanization and Environmental Impacts2013Licentiate thesis, monograph (Other academic)
    Abstract [en]

    The unprecedented growth of urban areas all over the globe is nowadays maybe most apparent in China having undergone rapid urbanization since the late 1970s. The need for new residential, commercial and industrial areas leads to new urban regions challenging sustainable development and the maintenance and creation of a high living standard as well as the preservation of ecological functionality. Therefore, timely and reliable information on land-cover changes and their consequent environmental impacts are needed to support sustainable urban development.The objective of this research is the analysis of land-cover changes, especially the development of urban areas in terms of speed, magnitude and resulting implications for the natural and rural environment using satellite imagery and the quantification of environmental impacts with the concepts of ecosystem services and landscape metrics. The study areas are the cities of Shanghai and Stockholm and the three highly-urbanized Chinese regions Jing-Jin-Ji, the Yangtze River Delta and the Pearl River Delta. The analyses are based on classification of optical satellite imagery (Landsat TM/ETM+ and HJ-1A/B) over the past two decades. The images were first co-registered and mosaicked, whereupon GLCM texture features were generated and tasseled cap transformations performed to improve class separabilities. The mosaics were classified with a pixel-based SVM and a random forest decision tree ensemble classifier. Based on the classification results, two urbanization indices were derived that indicate both the absolute amount of urban land and the speed of urban development. The spatial composition and configuration of the landscape was analysed by landscape metrics. Environmental impacts were quantified by attributing ecosystem service values to the classifications and the observation of value changes over time.

    ivThe results from the comparative study between Shanghai and Stockholm show a decrease in all natural land-cover classes and agricultural areas, whereas urban areas increased by approximately 120% in Shanghai, nearly ten times as much as in Stockholm where no significant land-cover changes other than a 12% urban expansion could be observed. From the landscape metrics analysis results, it appears that fragmentation in both study regions occurred mainly due to the growth of high density built-up areas in previously more natural environments, while the expansion of low density built-up areas was for the most part in conjunction with pre-existing patches. Urban growth resulted in ecosystem service value losses of ca. 445 million US dollars in Shanghai, mostly due to a decrease in natural coastal wetlands. In Stockholm, a 4 million US dollar increase in ecosystem service values could be observed that can be explained by the maintenance and development of urban green spaces. Total urban growth in Shanghai was 1,768 km2 compared to 100 km2 in Stockholm. Regarding the comparative study of urbanization in the three Chinese regions, a total increase in urban land of about 28,000 km2 could be detected with a simultaneous decrease in ecosystem service values corresponding to ca. 18.5 billion Chinese Yuan Renminbi. The speed and relative urban growth in Jing-Jin-Ji was highest, followed by the Yangtze River Delta and the Pearl River Delta. The increase in urban land occurred predominately at the expense of cropland. Wetlands decreased due to land reclamation in all study areas. An increase in landscape complexity in terms of land-cover composition and configuration could be detected. Urban growth in Jing-Jin-Ji contributed most to the decrease in ecosystem service values, closely followed by the Yangtze River Delta and the Pearl River Delta.

  • 154.
    Haas, Jan
    Karlstad University.
    Satellite monitoring of urbanization and estimation of environmental impact in Stockholm and Shanghai2013Other (Other academic)
  • 155.
    Haas, Jan
    Karlstad University.
    Spatio-temporal Analysis of Urban Ecosystem Services with Sentinel 2-A MSI data2017Other (Other academic)
  • 156.
    Haas, Jan
    Karlstad University.
    Synergies of Sentinel-1A SAR and Sentinel-2A MSI Data for Urban Ecosystem Mapping2015Other (Other academic)
  • 157.
    Haas, Jan
    KTH, Geodesi och geoinformatik.
    Utbud och efterfrågan på ekosystemtjänster i kinesiska megastäder2014In: Kart och Bildteknik, ISSN 1651-8705, E-ISSN 1651-792X, Vol. 4, p. 18-21Article in journal (Other (popular science, discussion, etc.))
  • 158.
    Haas, Jan
    et al.
    KTH, Geodesi och geoinformatik.
    Ban, Yifang
    KTH, Geodesi och geoinformatik.
    Bidecadal urban land cover and ecosystem service changes in three highly urbanized regions2013Conference paper (Refereed)
    Abstract [en]

    In the past 20 years, China has experienced rapid urbanization as a consequence of economic reforms and population growth.  Urbanization is still proceeding at staggering speed. Therefore, the development of effective analytical methods to monitor the unprecedented growth of Chinese cities and the resulting environmental impacts are crucial for urban planning and sustainable development. The overall objective of this research is to investigate urban land cover change between 1990 and 2010 and the resulting effects upon ecosystem services by analysis of multitemporal Landsat 5 and HJ1-A/B images in three highly urbanized regions.

  • 159.
    Haas, Jan
    et al.
    Karlstad University.
    Ban, Yifang
    Fusion of ENVISAT ASAR and HJ-1B optical data for urban land cover mapping in Beijing, China2011Report (Other academic)
  • 160.
    Haas, Jan
    et al.
    KTH, Geoinformatik.
    Ban, Yifang
    KTH, Geoinformatik.
    Mapping and Moitoring Urban Ecosystem Services Using High-Resolution Satellite DataManuscript (preprint) (Other academic)
  • 161.
    Haas, Jan
    et al.
    KTH.
    Ban, Yifang
    KTH.
    Mapping and Monitoring Urban Ecosystem Services Using Multitemporal High-Resolution Satellite Data2016In: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, ISSN 1939-1404, E-ISSN 2151-1535, Vol. 10, no 2, p. 669-680Article in journal (Refereed)
    Abstract [en]

    This study aims at providing a new method to efficiently analyse detailed urban ecological conditions at the example of Shanghai, one of the world’s most densely populated megacities. The main objective is to develop a method to effectively analyse high-resolution optical satellite data for mapping of ecologically important urban space and to evaluate ecological changes through the emerging ecosystem service supply and demand budget concept. Two IKONOS and GeoEye-1 scenes were used to determine land use/land cover change in Shanghai's urban core from 2000 to 2009. After pre-processing, the images were segmented and classified into seven distinct urban land use/land cover classes through SVM. The classes were then transformed into ecosystem service supply and demand budgets based on ecosystem functions. Decreases of continuous urban fabric and industrial areas in the favour of urban green sites and high-rise areas with commercial/residential function could be observed resulting in an increase of at least 20% in service supply budgets. Main contributors to the change are mainly the decrease of continuous urban fabric and industrial areas. The overall results and outcome of the study strengthen the suggested application of the proposed method for urban ecosystem service budget mapping with hitherto for that purpose unutilized high-resolution data. The insights and results from this study might further contribute to sustainable urban planning, prove common grounds for inter-urban comparisons or aid in enhancing ecological intra-urban functionality by analysing the distribution of urban eco-space and lead to improved accessibility and proximity to ecosystem services in urban areas

  • 162.
    Haas, Jan
    et al.
    KTH, Geodesi och geoinformatik.
    Ban, Yifang
    KTH, Geodesi och geoinformatik.
    Remote sensing of bidecadal urbanization and its impact on ecosystem service in the yangtze river delta2013In: Proceedings of Dragon 2 Final Results & Dragon 3 Kick-Off Symposium: 25-29 June 2012, Beijing, P.R. China, ESA Communications , 2013, p. 1-8Conference paper (Refereed)
    Abstract [en]

    The degree of urbanization and resulting effects on Ecosystem Services is investigated in the Yangtze River Delta in China within a 20 year time frame from 1990 to 2010. A Random forest classifier is used to classify the Landsat mosaic from 1990 and the HJ-1A/B mosaic dating from 2010. Urban Land Index (UI) and Urban Expansion Index (UX) are used to represent the intensity and rapidity of urbanization. Post-Classification Change Detection is then performed and Ecosystem Service value losses for the land-cover classes water, wetland, forest and cropland that transitioned to urban areas are calculated according to a valuation scheme adapted to the Chinese market. The results showed that Yangtze River Delta experienced significant urbanization during 1990 to 2010. Urban areas increased alongside a major decrease in cropland resulting in a substantial loss of 4.2 billion CNY in Ecosystem Services.

  • 163.
    Haas, Jan
    et al.
    KTH, Geodesi och geoinformatik.
    Ban, Yifang
    KTH, Geodesi och geoinformatik.
    Remote Sensing of Bidecadal Urbanization and its Impacts on Ecosytstem Service in the Yangtze River Delta2013In: Proceedings of Dragon 2 Final Results & Dragon 3 Kick-Off Symposium, 2013Conference paper (Other academic)
    Abstract [en]

    The degree of urbanization and resulting effects on Ecosystem Services is investigated in the Yangtze River Delta in China within a 20 year time frame from 1990 to 2010. A Random forest classifier is used to classify the Landsat mosaic from 1990 and the HJ-1A/B mosaic dating from 2010. Urban Land Index (UI) and Urban Expansion Index (UX) are used to represent the intensity and rapidity of urbanization. Post-Classification Change Detection is then performed and Ecosystem Service value losses for the land-cover classes water, wetland, forest and cropland that transitioned to urban areas are calculated according to a valuation scheme adapted to the Chinese market. The results showed that Yangtze River Delta experienced significant urbanization during 1990 to 2010. Urban areas increased alongside a major decrease in cropland resulting in a substantial loss of 4.2 billion CNY in Ecosystem Services.

  • 164.
    Haas, Jan
    et al.
    KTH, Geodesi och geoinformatik.
    Ban, Yifang
    KTH, Geodesi och geoinformatik.
    Satellite Monitoring of Urban Land Cover Changes and Assessing its Impact on Ecosystem Services in the Yangtze River Delta Between 1990 And 20102012Conference paper (Other academic)
  • 165.
    Haas, Jan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Ban, Yifang
    Royal Institute of Technology (KTH), Department of Urban Planning and Environment, Division of Geoinformatics, Stockholm, Sweden.
    Sentinel-1A SAR and sentinel-2A MSI data fusion for urban ecosystem service mapping2017In: Remote Sensing Applications: Society and Environment, ISSN 2352-9385, Vol. 8, p. 41-53Article in journal (Refereed)
    Abstract [en]

    The two main objectives of this study are to evaluate the potential use and synergetic effects of ESA Sentinel-1A C-band SAR and Sentinel-2A MSI data for classification and mapping of ecologically important urban and peri-urban space and to introduce spatial characteristics into ecosystem service analyses based on remotely sensed data. Image resolutions between 5 m and 20 m provided by the Sentinel satellites introduce a new relevant spatial scale in-between high and medium resolution data at which not only urban areas but also their important hinterlands can be effectively and efficiently mapped. Sentinel-1/2 data fusion facilitates both the capture of ecologically relevant details while at the same time also enabling large-scale urban analyses that draw surrounding regions into consideration. The combined use of Sentinel-1A SAR in Interferometric Wide Swath mode and simulated Sentinel-2A MSI (APEX) data is being evaluated in a classification of the Zürich metropolitan area, Switzerland. The SAR image was terrain-corrected, speckle-filtered and co-registered to the simulated Sentinel-2 image. After radiometric and spatial resampling, the fused image stack was segmented and classified by SVM. After post-classification, landscape elements were investigated in terms of spatial characteristics and topological relations that are believed to influence ecosystem service supply and demand, i.e. area, contiguity, perimeter-toarearatio and distance. Based on the classification results, ecosystem service supplies and demands accounting for spatial and topological patch characteristics were attributed to 14 land cover classes. The quantification of supply and demand values resulted in a positive ecosystem service budget for Zürich. The spatially adjusted service budgets and the original budgets are similar from a landscape perspective but deviate up to 50% on thepatch level. The introduction of spatial and topological patch characteristics gives a more accurate impression of ecosystem service supply and demands and their distributions, thus enabling more detailed analyses in complexurban surroundings. The method and underlying data are considered suitable for urban land cover and ecosystem service mapping and the introduction of spatial aspects into relative ecosystem service valuation concepts is believed to add another important aspect in currently existing approaches.

  • 166. Haas, Jan
    et al.
    Ban, Yifang
    Synergies of Sentinel-1A and Sentinel-2A MSI Data for Urban Ecosystem Service Mapping2015Conference paper (Refereed)
  • 167.
    Haas, Jan
    et al.
    KTH, Geodesi och geoinformatik.
    Ban, Yifang
    KTH.
    Urban growth and environmental impacts in Jing-Jin-Ji, the Yangtze, River Delta and the Pearl River Delta2014In: International Journal of Applied Earth Observation and Geoinformation, ISSN 0303-2434, Vol. 30, no 1, p. 42-55Article in journal (Refereed)
    Abstract [en]

    This study investigates land cover changes, magnitude and speed of urbanization and evaluates possible impacts on the environment by the concepts of landscape metrics and ecosystem services in China's three largest and most important urban agglomerations: Jing-Jin-Ji, the Yangtze River Delta and the Pearl River Delta. Based on the classifications of six Landsat TM and HJ-1A/B remotely sensed space-borne optical satellite image mosaics with a superior random forest decision tree ensemble classifier, a total increase in urban land of about 28,000 km(2) could be detected alongside a simultaneous decrease in natural land cover classes and cropland. Two urbanization indices describing both speed and magnitude of urbanization were derived and ecosystem services were calculated with a valuation scheme adapted to the Chinese market based on the classification results from 1990 and 2010 for the predominant land cover classes affected by urbanization: forest, cropland, wetlands, water and aquaculture. The speed and relative urban growth in Jing-Jin-Ji was highest, followed by the Yangtze River Delta and Pearl River Delta, resulting in a continuously fragmented landscape and substantial decreases in ecosystem service values of approximately 18.5 billion CNY with coastal wetlands and agriculture being the largest contributors. The results indicate both similarities and differences in urban-regional development trends implicating adverse effects on the natural and rural landscape, not only in the rural-urban fringe, but also in the cities' important hinterlands as a result of rapid urbanization in China.

  • 168.
    Haas, Jan
    et al.
    KTH.
    Ban, Yifang
    KTH.
    Urban Land Cover and Ecosystem Service Changes based on Sentinel-2A MSI and Landsat TM Data2018In: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, ISSN 1939-1404, E-ISSN 2151-1535, Vol. 11, no 2, p. 485-497Article in journal (Refereed)
    Abstract [en]

    Sustainable development in metropolitan regions is challenging in the light of continuous urbanization. Remote sensing provides timely and reliable information on urban areas and their changing patterns. This study's objectives are to evaluate the contribution of Sentinel-2A (S-2A) data to urban ecosystem service mapping and to investigate spatial ecosystem service characteristics with landscape metrics through a novelmethod. Service pattern changes between 2005 and 2015 are mapped for Beijing, China. Landscape metrics are used to qualitatively evaluate urban ecosystem service provision bundle changes. S-2A and Landsat TM data are segmented and classified with SVM, distinguishing three artificial and four natural classes based on ecosystem function. Spatial characteristics influencing ecosystem services are quantified with seven landscape metrics. Beijing's urban development is characterized by reduction in agricultural areas in the urban fringe in favor of built-up areas, urban green space, and golf courses. A transformation of old suburban agglomerations into urban green space can be observed. The planar increase in urban areas is accompanied by the creation of managed urban green space. Service bundles based on land cover classes and spatial characteristics decreased more than 30% for bundles that represent food supply, noise reduction, waste treatment, and global climate regulation. Temperature regulation/moderation of climate extremes, recreation/place values/social cohesion, and aesthetic benefits/cognitive development are least affected. This new approach of extending the ecosystem service concept through integration of spatial characteristics of ecosystem service provisional patches through landscape metrics is believed to give a more realistic appraisal of ecosystem services in urban areas.

  • 169.
    Haas, Jan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). KTH, Geodesi och geoinformatik.
    Furberg, Dorothy
    KTH, Geodesi och geoinformatik.
    Ban, Yifang
    KTH, Geodesi och geoinformatik.
    Satellite monitoring of urbanization and environmental impacts: A comparison of Stockholm and Shanghai2015In: International Journal of Applied Earth Observation and Geoinformation, ISSN 0303-2434, Vol. 38, p. 138-149Article in journal (Refereed)
    Abstract [en]

    This study investigates urbanization and its potential environmental consequences in Shanghai andStockholm metropolitan areas over two decades. Changes in land use/land cover are estimated fromsupport vector machine classifications of Landsat mosaics with grey-level co-occurrence matrix fea-tures. Landscape metrics are used to investigate changes in landscape composition and configurationand to draw preliminary conclusions about environmental impacts. Speed and magnitude of urbaniza-tion is calculated by urbanization indices and the resulting impacts on the environment are quantified byecosystem services. Growth of urban areas and urban green spaces occurred at the expense of croplandin both regions. Alongside a decrease in natural land cover, urban areas increased by approximately 120%in Shanghai, nearly ten times as much as in Stockholm, where the most significant land cover changewas a 12% urban expansion that mostly replaced agricultural areas. From the landscape metrics results,it appears that fragmentation in both study regions occurred mainly due to the growth of high densitybuilt-up areas in previously more natural/agricultural environments, while the expansion of low densitybuilt-up areas was for the most part in conjunction with pre-existing patches. Urban growth resulted inecosystem service value losses of approximately 445 million US dollars in Shanghai, mostly due to thedecrease in natural coastal wetlands while in Stockholm the value of ecosystem services changed very lit-tle. Total urban growth in Shanghai was 1768 km2and 100 km2in Stockholm. The developed methodologyis considered a straight-forward low-cost globally applicable approach to quantitatively and qualitativelyevaluate urban growth patterns that could help to address spatial, economic and ecological questions inurban and regional planning.

  • 170.
    Haas, Jan
    et al.
    KTH, Geodesi och geoinformatik.
    Jacob, Alexander
    KTH, Geodesi och geoinformatik.
    Ban, Yifang
    KTH, Geodesi och geoinformatik.
    Urban ecosystems mapping from spaceborne high-resolution optical data2014In: Proc. ‘Dragon 3 Mid-Term Results Symposium’, Chengdu, P.R. China 26–29 May 2014 (ESA SP-724, November 2014), 2014Conference paper (Refereed)
    Abstract [en]

    The potential of high-resolution optical satellite images for mapping of ecologically important urban space is investigated in this study. Both a GeoEye-1 and a Landsat 8 scene over central Shanghai were first segmented by two different algorithms and then classified into seven urban classes by SVM. Shadows in the pan-sharpened GeoEye-1 image were masked out and replaced by the corresponding pan-sharpened classified Landsat 8 image. Largest confusions occurred between sealed and permeable but non-vegetated surfaces, and between low-rise residential and high-rise commercial buildings. Based on the classification result, ecosystem service balances, supply and demand was modelled for each particular land cover class. Classification accuracies of 88% and 91% could be reached, indicating the suitability of the underlying data and method for this application domain. The KTH-SEG segmentation algorithm slightly outperformed the one implemented in eCognition. The highest supply of ecosystem services was found in water bodies whereas high-rise built-up areas revealed largest demands.

  • 171. Hall, P.
    et al.
    Anderson, L.
    Holby, Ola
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Kollberg, S.
    Samuelsson, M.-O.
    Chemical fluxes and mass balances in a marine fish cage farm1990In: Carbon. Mar. Ecol. Progr. Ser. 61 : 61-73Article in journal (Refereed)
  • 172. Hall, P.
    et al.
    Holby, Ola
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Kollberg, S.
    Samuelsson, M.-O.
    Chemical fluxes and mass balances in a marine fish cage farm1992In: Nitrogen. Mar. Ecol. Progr. Ser. 89 : 81-91Article in journal (Refereed)
  • 173. Hameroff, S.R.
    et al.
    Rasmussen, S.
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Molecular Automata in Microtubules: Basic Computational Logic of the Living State?1988In: C. Langton (ed.), Artificial Life, sid. 521-553, Addison-Wesley , 1988Chapter in book (Other academic)
  • 174.
    Hammar, Martin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Verktyg för att analysera Karlstad Centralsjukhus värme & kylproduktion2012Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The Worlds energy usage has dramatically increased since the 1970's and as a consequence also the prices for energy. This creates incentives for investments with the purpose to decrease energy costs, which is a development you can see in the industry, transport and building sectors.

    Karlstad Central Hospital is no exception with a floorspace equivalent of 26 football fields and activity around the clock. Just to heat and cool the hospital to a pleasant climate consumes a large amount of energy. Currently the parts of the hospital is being rebuilt to reduce its energy consumption. In September 2010 the hospital's energy production changed . When six heatpumps were installed, two linked to hospital cooling system to recover heat and four to geothermal heat by 81 boreholes and the river Klarälven, which runs past the hospital. Long-distance heating is used for peak loads and in reserve when the heat pumps cannot supply all heating needs. The hospital's cooling is produced by the two heat pumps, three cooling machines and free cooling from the geothermal connection.

    When designing the new energy production it was meant that the heat pumps should produce the heat required to -4 ° C, the rest would be covered by long-distance heating. The boreholes would make possible to storage energy between seasons. But operation of the plant has shown that reality differs from the theory. The heatpumps have not been fully utilized during the winter when neither the geothermal or the river behaved as intended. The operating strategy that was developed during project planning valid and therefore needs to be revised. This thesis is a step in that effort. The project's objectives was to produce a tool to analyze the hospital's operating history in cooperation with the Central Hospital's engineering staff. The tools users is meant to be the same staff so its design must be easily understood for those. A trialperiod took place therefore before the final handover.

    The tool was developed in Microsoft Excel and it creates four graphs showing the operational history of each year. Two of them are showing the heat- or cold-output in kilowatts for a year and what produces this output. The other two shows the cost in thousand swedish crowns to produce these effects. The tool calculates thus by collecting data from power and temperatur gauges installed in the hospitol and is collected by the monitoring program Citec och statistics program WebEss. By comparing the power and cost graph for heat it can be seen for example what heat pumps produced and how much the production cost.

    A key word in the development of the tool has been simplicity for the users. The tool should be easy and fast to update and simple to understand, which was achieved. After a week's trial had been running the staff had no wanted changes so the tool was handed over.

  • 175.
    Hasso, Ahmed
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Köpa fryst eller färskt livsmedel: En studie om hur svinn i konsumentled påverkar energi- och klimatanalysen2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Food is expected to be one of the biggest causes of energy use for households, leading to large amounts of greenhouse gas emission that impact the climate. Food is the energy resource that one needs for his/her continuous energy intake, where a Swedish consumes 0.35 tons annually. A third of the food which is produced is discarded as waste, of which 60% may be reduced.

    Food waste occurs because of poor planning when purchasing and cooking food, where larger amount or wrong type of food is purchased. If it is not possible to reduce the amount of the discarded food, the remains should be handled in such a way that the impact on the climate and the energy consumption is minimized.

    A disposal method that can reduce food waste may be to purchase frozen food instead of fresh to be stored in the freezer, which gives the advantage of extending the lifetime of it.  This disposal method requires a lot of energy, and thereby the greenhouse gases occurs. Frozen foods need to be thawed before cooking which may increase energy consumption. If frozen foods are rejected, it could mean a larger amount of food waste, which could be used to produce biogas. This fuel can be used as gas for vehicles and can replace fossil fuels, which to some extent can reduce climate impact of the large waste of resources. It can also happen that food ends up in landfills and the energy that could have been recovered is wasted. Frozen foods need to be thawed before cooking.

    This report examines the differences in energy consumption and climate impact for some fresh and frozen foods depending on the different approaches and assumed amounts of waste. The survey is carried out for a number of products that are available in the market as fresh and frozen products, and where data on climate impact of products are available in the literature. For the study, pork, beef, chicken, potatoes /chips, raspberries, peas and bread were studied. The energy used for producing frozen food from the cultivation/production even thawing without wastage is set against the energy used to produce fresh food. The same calculation is performed to calculate the greenhouse gas emissions. The parameters such as COP value of the fridge, storage time in the freezer, the digestion of the discarded food quantity and the choice of electricity generation will be investigated to see the effect of these parameters on the result.

    The results show that it is rarely feasible, from an energy and climate point to view, to purchase frozen products although the wastage is assumed to be zero. One of the factors that matters is the energy consumption and climate impact for cultivation/production and processing of food. Freezing means relatively large inputs of energy added in the processing and during transport. This added amount of energy equivalent to relatively large amounts of wastage of the fresh food product.  This effect is reduced with large margins if the discarded food quantity is disposed. If the food producers use electricity produced in Sweden, the climate impact and the corresponding amount of fresh food that can be disposed will be reduced slightly.

  • 176.
    Hedelin, Beatrice
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Criteria for the assessment of planning processes for sustainable river basin management: Illustration by two cases: The EU water framework directive and ongoing water planning processes in Sweden2008In: Adaptive and Integrated Water Management: Coping with Complexity and Uncertainty, Berlin: Springer , 2008, p. 405-422Chapter in book (Refereed)
    Abstract [en]

    This paper examines a set of criteria for processes that aim to attain sustainable river basin planning at the regional scale. The criteria answer to the lack of deductive methodologies for the assessment and development of participatory approaches to water planning. They are derived from the two concepts and sustainability principles participation and integration. The criteria are here explained and their use is illustrated by presentation of the results and conclusions from two case studies. The first case concerns an assessment of the EU Water Framework Directive (WFD). — In what ways does the WFD support or obstruct processes for sustainable water management? The second case concerns the ongoing planning processes in Sweden that follow from the implementation of the WFD. The cases show that the criteria work well in achieving their purpose as their use resulted in practicable proposals for taking the studied planning objects closer to meeting the criteria.

  • 177.
    Hedelin, Beatrice
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Criteria for the Assessment of Processes for Sustainable River Basin Management and their Congruence with the EU Water Framework Directive2008In: European Environment, ISSN 0961-0405, E-ISSN 1099-0976, Vol. 18, p. 228-242Article in journal (Refereed)
    Abstract [en]

    In order to manage the increasing pressure on the world's water resources, new planning methodologies/processes for sustainable river basin management are currently being developed. For such processes to work well, however, the legal context must allow, or support, such processes. In this study, a set of criteria relating to methodologies/processes for sustainable water management is used to assess the EU Water Framework Directive (WFD). The study suggests that the WFD erects few formal barriers to good planning practices. However, planning processes will need to be adapted to compensate for the weak legal support in a number of important areas, namely the use of knowledge from beyond the natural sciences, the use of methodologies for the explicit handling of values and the use of procedures for democratic participation. In so doing the issues identified here provide a basis for systematic thinking about how to design the necessary planning processes. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment.

  • 178.
    Hedelin, Beatrice
    Karlstad University, Faculty of Technology and Science.
    Criteria for the Assessment of Sustainable Water Management2007In: Environmental Management, ISSN 0364-152X, E-ISSN 1432-1009, Vol. 39, no 2, p. 151-163Article in journal (Refereed)
    Abstract [en]

    Pressure on the world’s water resources is increasing, restraining social and economic development in many countries, and threatening ecological values in others. In order to manage water resources in a more sustainable manner, new planning methodologies/processes for river basin management need to be developed. This study attempts to construct a set of useable normative criteria for the analysis and evaluation of such processes. The criteria were designed as a response to the lack of deductive approaches in the evaluation of methodologies and working procedures used in the context of river basin management, making it possible to highlight their potential for sustainable development. The criteria are based on the twin concepts of participation and integration. These concepts function as well-established dimensions of both sustainable development and sustainable river basin management, and they are of significant methodological relevance. A synthesis of the key aspects connected to the two concepts is undertaken, based on a broad literature review. Focus is laid on how in methodological terms, and in relation to regional water management, to achieve participation and integration in a decision-making or planning process. The criteria are concerned with how knowledge and values are integrated into the planning process and how commitment, legitimacy, or acceptance for the resulting plan is generated.

  • 179.
    Hedelin, Beatrice
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Planning for Sustainable Use of Water2008Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    The basic problem that this work wishes to address concerns the  unsustainable use of water resources in many places of the world. In some places, the problem leads to human suffering and death while also obstructing social and economic development. In other places, where the consequences are less severe, natural environments are seriously damaged. A significant part of the solution to this problem lies in the planning and decision-making domain. The overall aim of this thesis is therefore to contribute to the available knowledge on planning and management for the sustainable use of water resources. Planning as a process is in focus, both in itself and in the organisational and legal contexts that affect how planning processes are performed.

     

    The main methodological approach used, and the theoretical contribution made here, is the deriving and discussion of a set of deductive criteria for the development and assessment of planning processes for the sustainable use of water resources (Papers III and IV). The criteria were derived using a multi-disciplinary approach, where the relevant literature on how to transform the concepts of ‘integration’ and ‘participation’ – both key principles for sustainable development in relation to planning – into an analytical framework of twelve criteria, was reviewed and synthesised. The derived criteria concern issues such as, how to integrate knowledge and values into the planning process and how to generate commitment, legitimacy or acceptance for the resulting plan, by democratic means. The criteria are then used to assess the EU Water Framework Directive (WFD) – an extensive legal framework which will steer water planning in the EU Member States for several decades to come – and to assess the planning processes that follows on from WFD implementation in Sweden.

     

    The analysis contained in (Paper V) showed that the WFD erects few formal barriers to good planning practices. The analysis also showed however, that the planning processes that follow on from its implementation will need to be adapted to compensate for the weak legal support in a number of important areas, namely, the use of knowledge from beyond the natural sciences, the use of methodologies for the explicit handling of values and the use of procedures for democratic participation. Several recommendations are also made in respect of how the WFD could be supplemented in order for it to become a stronger support in planning processes for the sustainable use of water.

     

    The analysis of the ongoing water planning processes in Sweden (Paper VI) showed that knowledge of how to work with values and how to create forms and methods of participation and collaboration remain clearly underdeveloped. In consequence, the main objectives behind participation – the provision of knowledge and perspectives for the process and the creation of legitimacy, acceptance or engagement – are actually at risk. Recommendations include complementing the existing knowledge base with insights from the social sciences and the humanities, to create well informed learning systems within the new water administration and to make use of alternative methods for the handling of values.

     

    In addition to this, two papers from the thesis (Papers I and II) concern the situation pertaining before WFD implementation in Sweden. By comparing the system for municipal land and water planning (the former main system for long-term water planning in Sweden) with WFD prescriptions, and with the organisation of the new water administration bodies, some potential implications of WFD implementation were identified. From here it followed, that the development of forms of co-operation between the concerned administrative organisations, and in respect of the democratic involvement of the public and other concerned actors, were crucial in creating an integrative, effective and democratic system for water planning in Sweden.

     

    The thesis also illustrates the use of a tentative model for the operationalisation of ‘sustainable development’. The tentative model is described in the thesis, and it constitutes the methodological baseline for the thesis, since five of the papers contained herein use various approaches related to this model.

  • 180.
    Hedelin, Beatrice
    Division for Engineering Sciences, Physics and Mathematics, Karlstad University.
    Potential Implications of the EU Water Framework Directive in Sweden: A Comparison of the Swedish municipalities' Current Water Planning Regime with the Requirements of the EU's New Water Framework Directive2005In: European Journal of Spatial Development, ISSN 1650-9544, E-ISSN 1650-9544, Vol. May, no 14Article in journal (Refereed)
    Abstract [en]

    The Water Framework Directive (WFD) is currently being implemented throughout Europe. As the Directive is likely to introduce major changes to the way in which water is managed in Sweden, this study aims to highlight some of the potential implications of its implementation. The requests of the WFD are compared with the current Swedish municipal system for water planning. Both organisationally and in terms of actual content the current study highlights significant differences in both approach and outcomes. The organisational changes envisaged will bring about a situation where, in essence, two parallel water management planning systems exist. This however implies that there will be significant problems ahead in terms of accountability and legitimacy, as the formal relationship between these separate systems is not clear, while thenew system lacks clear linkages to the representative democratic model. The identified differences in terms of content however imply a more effective approach to water management and the potential for a more informed planning process. In order to make this arrangement work, forms of effective co-operation between the municipalities and the Water Authorities, as well as for the involvement of the general public and other concerned interests, need to be developed.

  • 181.
    Hedelin, Beatrice
    et al.
    Division for Engineering Sciences, Physics and Mathematics, Karlstad University.
    Gustafsson, Jan-Erik
    Department of Land and Water Resources Engineering, KTH.
    Swedish Water Management: A Comparison of some Municipal Master Plans and the Requests of the Water Framework Directive2003In: Vatten, ISSN 0042-2886, Vol. 59, no 2, p. 75-80Article in journal (Other academic)
    Abstract [en]

    A selection of 14 Swedish municipal master plans have been compared with the requirements of future river basin plans, as prescribed in the Water Framework Directive. The municipal master plans can be considered as the main planning documents to provide guidance for decision-making on water use in Sweden. Thus, they represent the long-term plans for water use. The comparison gives a hint on what effect the implementation of the Water Framework Directive will have on the Swedish water management system.The result shows that most of the prescribed contents of the river basin plan are covered very briefly, or not covered at all, in the master plans. Economic analysis, environmental goals and monitoring are issues that are covered in a highly defective way, compared to what is prescribed for the future river basin plans. Only the identification of protected areas are covered to a high extent. The conclusion is that implementation of the Water Framework Directive will not only change the form of administration and management of water resources in Sweden. Many new aspects concerning the substance and content of water management must also be considered in the future.

  • 182.
    Hedelin, Beatrice
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Lindh, Magnus
    Karlstad University, Faculty of Social and Life Sciences, Department of Politics and History.
    Implementing the EU Water Framework Directive: Prospects for Sustainable Water Planning in Sweden2008In: European Environment, ISSN 0961-0405, E-ISSN 1099-0976, Vol. 18, no 6, p. 327-344Article in journal (Refereed)
    Abstract [en]

    Implementation of the EU Water Framework Directive will significantly affect the way in which water issues in Europe are managed. Here, a set of criteria for processes for sustainable river basin planning is used as a basis for analysing how the responsible planners in one EU member state – Sweden – carry out the work prescribed by the WFD. The paper is based on 13 interviews with water planners and directors. The current processes represent progress in relation to the situation pertaining before implementation; e.g., participation and collaboration are increasingly becoming pivotal, knowledge of the natural water state is increasing and the economy of water is emerging as a new and important issue. The interviews do however show that knowledge of how to work with values and how to create forms and methods of participation and collaboration remain clearly underdeveloped. In consequence, the main objectives behind participation – the provision of knowledge and perspectives for the process and the creation of legitimacy, acceptance or engagement – are actually at risk. Recommendations include complementing the existing knowledge base with insights from the social sciences and the humanities, to create well informed learning systems within the new water administration and to make use of alternative methods for the handling of values. The Swedish case may provide useful insights for other member states. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment.

  • 183.
    Hekkala, Madeleine
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Reduktion av växthusgasutsläpp och återvinning av spillvärme inom kemisk processindustri: Alternativa systemlösningar för värme-, ång- och elproduktion vid Akzo Nobel Adhesives AB2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Combustion of fossil fuels increases the concentration of greenhouse gases in the atmosphere, and the natural greenhouse effect of the Earth is enhanced. The European Union has set energy and climate targets to reduce greenhouse gas emissions by 80-95% compared with 1990. 

    At Akzo Nobel Adhesives AB in Kristinehamn, steam is now being used for production processes and for heating water and factory premises. The steam requirement is partially met with oil-fired boilers, which annually results in 3000 tons of CO2. On the site, energy-rich waste heat flows are also found in form of excess steam, high-temperature flue gases and residual water from cooling processes. The AkzoNobel Group itself has an internal, international goal to become carbon neutral and use 100% renewable energy by 2050. The use of fossil fuels is something that has to be phased out to achieve this goal. The use of fossil fuel in combination with the large amount of waste heat released into the environment are two factors that require action if the Group is also to help and contribute to achieving the European Union's energy and climate goals. 

    The purpose of this thesis was therefore to review the steam diagram and chart energy-rich waste heat flows at the Kristinehamn plant to investigate alternative solutions that would replace the steam production from the fossilized boilers in whole or in part. The actions investigated are alternative steam production, alternative methods of heating and electricity generation in situ. Alternative system solutions have been studied individually and in selected combinations based on a decision tree. System solutions were assessed based on cost reduction, reduced amount of CO2-emissions and share of recovered waste heat. 

    The system solution that results in the largest total cost reduction (4.8 MSEK) is to switch to a biofueled boiler, to meet the heat demand with upgraded residual water via heat pump, and to produce electricity with surplus steam and extra steam produced through a condensing turbine. The same system solution but with any fuel to the boiler (oil or wood powder) is also the one that performs best with regard to the amount of recovered waste heat (25.7 GWh). The system solution with the largest total reduction of CO2-emissions (6150 tons) is to switch to wood powdered boilers, to meet the heat demand with district heating, and to produce electricity with excess steam and additional produced steam through a condensing turbine. However, this system solution becomes more expensive on an annual basis. All these three systems perform even better with integrated ORC. 

    Based on the results, it can be concluded that when measures are taken to recover waste heat, the annual cost reduction increases. A conclusion that can also be drawn from this study is that individual solutions are not always better from an energy-flow perspective. All combinations that are technically possible are also not suitable. In conclusion, there are good opportunities to reduce annual costs, reduce annual CO2 emissions and recover available waste heat energy with different technologies.

  • 184.
    Henriksson, Lisa
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Frodeson, Stefan
    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).
    Andersson, Simon
    Emerging Cooking Solutions Sweden AB.
    Ohlson, Mattias
    Emerging Cooking Solutions Sweden AB.
    Bioresources for Sustainable Pellet Production in Zambia: Twelve Biomasses Pelletized at Different Moisture Content2019In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 14, no 2, p. 2550-2575Article in journal (Refereed)
    Abstract [en]

    The use of charcoal and firewood for cooking is common in Zambia,and its utilization is suchthat the deforestation rate is high, energy utilization is low, and unfavorable cooking methods lead to high death rates due to indoor air pollution mainly from particulate matter and carbon monoxide.Byusing an alternative cooking method, such as pellet stoves, it is possible to offer a sustainable solution, provided that sustainable pelletproduction can be achieved. In this study, 12different available biomaterials were pelletizedina single pellet unitto investigate their availability as raw materials for pellet production in Zambia. The study showedthat sicklebush and pigeon pea generatedthe same pelleting properties correlated withcompression and frictionand that both materials showedlow moisture uptake. The study also identifiedtwo groups of materials that broadenedthe raw material base and helpedto achieve sustainable pellet production.Group 1consisted of materials with equal pelletingabilities (miombo, peanut shell, pigeon pea,and sicklebush) andGroup 2 consistedof materialsthat showed low impact of varying moisture content(eucalyptus, miombo, peanut shell, pigeon pea, and sicklebush). The hardest pellet was made from Tephrosia, which wasfollowed by Gliricidia.

  • 185.
    Hernandez Campos, Harold
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Systemanalys över elförsörgning av ett teknikhus med BIPV2013Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
  • 186.
    Hognert, Johannes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Förgasning av avfall för vätgasproduktion: Integration av en förgasningsprocess i ett värmeverk2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Waste and fossil fuels count as two great threats for the environment in today’s society. As the world population continues to increase so does consumption and levels of waste plus the usage of fossil fuels. When the waste levels keep increasing the demand for waste treatment methods becomes higher than ever. Combine this with the increasing usage of fossil fuel which feeds the demand for alternative fuels. This master thesis has been carried out to evaluate a method in which both of these global issues are addressed. Hydrogen production through gasification of municipal solid waste is a new method of waste treatment where the product has the potential to replace fossil fuels.

    Gasification is a chemical recycling method in which a carbon-based material gets oxidized in an oxygen free or limited environment. The chemical process is not far from traditional oxidation, combustion. The fact is that also traditional combustion reactions have a certain role within a gasification process although full combustion is avoided due to the lack of oxygen. The gasification of waste is commenced with an oxidant such as pure oxygen or steam. Depending on the oxidant the process can be either endothermic or exothermic. If steam is used as an oxidant the process is endothermic and heat has to be introduced to the system.

    The gasification study issued by He et al. (2009a) is widely used as a reference in this thesis because of their result producing a syngas with high hydrogen level and low tar content. As far as possible the gasification method of this thesis has been imitative to the one of He et al. (2009a) with the only difference being an adjustment so that heat transfer is possible from Hovhult heat plant. This is the reason why a double fluidized bed has been chosen as gasification reactor. The heat plant is located at Hovhult in Uddevalla and data has been delivered by Uddevalla Energi from their production during 2014.

    The main focus of the thesis is to calculate the energy flows of the system, which includes the gasification reactor, the heat plant, hydrogen separation, steam and gas turbine. These calculations have been carried out in a model that has been built in Excel. The energy flows and the processes within the system have been integrated in a way so that energy conservation within the system is maximized. In addition, the heat demand from the district heat network has been met in all cases. Furthermore, Swedish and European legislation has been investigated in order to classify the combined gasification and heat plant and determine where in the process the waste is considered to be a product instead of waste.

    The result shows that enough heat is produced to meet the district heat requirements and also that hydrogen and electricity can be produced during the process. The energy efficiency of the system has been calculated to 82.5 %. A problem that needs to be handled is the amount of excess heat produced during the summer months. The analysis of the legislation regarding waste and especially the Lahti Energia Case C-317/07 shows that the gasification unit should be classified as a co-incineration plant that produces hydrogen. The waste is assumed to transform into a product the instant it is gasified.

  • 187.
    Holby, Ola
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Biogeochemical processes in fish farm deposits and Weddell Sea sediments1991Report (Other academic)
  • 188.
    Holby, Ola
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Anderson, Leif G.
    Geochemistry in an area recently uncovered from the Filchner Ice Shelf1996In: Continental Shelf Research,Vol. 16, No11, pp. 1479-1488Article in journal (Refereed)
  • 189.
    Holby, Ola
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Evans, Sverker
    The vertical distribution of Chernobyl-derived radionuclides in a Baltic Sea sediment1996In: Journal of Environmental Radioactivity, Vol 33, No. 2, pp.129-145Article in journal (Refereed)
  • 190.
    Holby, Ola
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Hall, P.
    Chemical fluxes and mass balances in a marine fish cage farm1991In: II. Phosphorus. Mar. Ecol. Progr. Ser. 70: 263-272Article in journal (Refereed)
  • 191.
    Holby, Ola
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Hall, Per O.J.
    Chemical fluxes and mass balances for a marine fish cage farm1994In: Silicon. Aquaculture 120: 305-318Article in journal (Refereed)
  • 192.
    Holby, Ola
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Sachs, Oliver
    Sauter, Eberhard J
    Schlueter, Michael
    Rutgers van der Loeff, Michiel M
    Jerosch, Kerstin
    Benthic organic carbon flux and oxygen penetration reflect different plankton provinces in the Southern Ocean2009In: Deep Sea Research Part I: Oceanographic Research Papers, ISSN 0967-0637, E-ISSN 1879-0119, Vol. 56, no 8, p. 1319-1335Article in journal (Refereed)
  • 193.
    Holby, Ola
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Tengberg, A.
    De Bovee, F.
    Hall, P.
    Berelson, W.
    Chadwick, D.
    Cicceri, G.
    Crassous, P.
    Devol, A.
    Emerson, S.
    Glud, R.
    Graziottin, F.
    Gundersen, J.
    Hammond, D.
    Helder, W.
    Hinga, K.
    Holby, O.
    Jahnke, R.
    Khripounoff, A.
    Khripounoff, A.
    Lieberman, S.
    Nuppenau, V.
    Pfannkuche, O.
    Benthic chamber and profiling landers in oceanography - A review of design, technical solutions and functioning1995In: Prog. Oceanog. Vol 35:253-294Article in journal (Refereed)
  • 194. Horsch, Helga
    et al.
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Konzept der ökologisch-ökonomische Bewertung von erneuerbaren Ressourcen ' dargestellt am Beispiel des Grundwasserschutzes im Torgauer Raum1998Report (Refereed)
  • 195.
    Hultin, Isabelle
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Tidseffektivisering av Stora Ensos emballeringsprocess: Simulering av värmeledning och luftflödesberäkningar2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Stora Enso Skoghall Mill is one of the world’s greatest manufacturers of paperboard. Every six paperboard package containing a liquid is made at Skoghall Mill. Paperboard has a small environmental impact since the main product, wood, is a natural source. Paperboard can have many different properties and vary in appearance and strength depending on the amount of fiber used in manufacture. Paperboard is not sealable by itself but can, with other adhesive materials be sealed. Stora Enso is producing paperboard on rolls which later are sent off to the customers. Before they sent them to the customers, the rolls are packed in protective paperboard before transportation. This process is called the packaging process.The purpose of this study was to make the packaging process more time efficient. Stora Enso currently has an overcapacity in the packaging process and the process is a bottleneck for the production. The process end press has been studied since it was more time consuming than surrounded processes. When the paperboard rolls enter the end press, the last packaging is added. The paperboard rolls has earlier been wrapped with inner pads on the ends and cover around. The end press consists of two heated plates with outer pads added. The heated plates purpose are to seal the paperboard rolls by melting the outer layer of the outer pad, the LDPE layer, to the paperboard rolls ends. The heated plates temperature is fixed at 180 °C and the plates are moving towards the paperboard rolls with three different velocities which are gradually decreased the closer the heated plates gets to the paperboard rolls. For later during seven seconds pressing the outer pads to the paperboard rolls ends.The goal with this study was to make the end press more time efficient and make a recommendation in which way the improvements should be handled. The simulation software COMSOL Multiphysics has been used to build the system, simulate the real cases and then making them more time efficient by decreasing the cycle time. The time in which the outer pads are pressed to the paperboard rolls ends was studied in a 3D-model. To find out if the pressing time was the most optimal, the temperature on the paperboard rolls ends outer layer was simulated during pressing. The heat transfer between the LDPE-layer of the outer pad and the paperboard roll were assumed to increase until the paperboard rolls ends reached the temperature of the heated plates 180 °C. Later, it was studied if the LDPE-layer could be replaced by a material which makes the heat conduction go faster. Density, specific heat capacity and thermal conductivity were factors which were varied. The maximum velocities of the heated plates were studied by calculations. The air between the heated plate and the paperboard roll were assumed to have a cylindrical shape and the air flow through the cylinder was calculated by the Reynolds number. The velocity of the heated plates was assumed to be increased as long as the air flow was laminar. It was also examined if the movement of the heated plates could begin earlier since the heated plates with added outer pads are standing still under different time before the heated plates start moving.To make the end press more time efficient, four improvements are recommended as follows: decrease the pressing time, start the movement of the heated plates earlier, replace the LDPE-layer and increase the velocity of the heated plates. The improvements are recommended in order of what was assumed to be easiest and least time consuming for the company.The simulations showed that the pressing time can be decreased to 3-3.5 seconds since no heat transfer occurred between the heated plates and the paperboard roll after this time. This improvement provides a time saving of 3.5-4 seconds. To start the movement of the heated plates earlier was possible since they are standing still with added outer pads 3.35-9.33 seconds before the movement starts. The company is recommended to start the movement of the heated plates after 3.35 seconds regardless of the width of the paperboard rolls. This improvement could save up to 5.98 seconds.It is recommended to replace the LDPE-layer by a material with higher thermal conductivity and density, but with similar adhesive properties. A time saving of one second can be done if the thermal conductivity is changed from 0.33 to 0.5 W/mK at the same time as the density is changed from 605 to 800 kg/m3.Calculations of the air flow showed that the maximum velocity of the heated plates was 16.37 m/s at the distance 1700 mm from the paperboard roll. To make this improvement, a reprogramming of the heated plates movement is required, from three velocity stages to one velocity which decrease as the distance between the heated plates and the paperboard roll decrease. This is the last recommended improvement since it is believed to be the most challenging one for the company and a reconstruction may be needed. The calculated maximum velocity of the heated plates was about 40 times greater than the fast velocity of the heated plates today and therefore the company should be able to increase the fast velocity and the medium velocity. Four seconds is the optimal time saving to avoid waiting time between the sub processes before and after the end press. A time saving of four seconds could easily be done by using the calculated maximum velocities.If all improvements are done a time saving of 15 seconds can be made. Since the optimal time saving is four seconds, the company can choose which improvements that should be done and in which extent. A time saving of four seconds means that the cycle time of the end press is reduced by 12-13 %, while the production capacity increase with same rate.

  • 196.
    Häggström, Anton
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Vindkraftens påverkan på svensk elproduktion: Förändringar av vatten-, kärn- och värmekraftsproduktion vid ökad andel vindkraft2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In recent years, wind power has significantly increased in prevalence and in production of energy. Indications have been made, that this trend will continue as the funding through the Swedish “elcertifikatssystemet” and “vindpilotstödet” has been extended and renewed respectively. The Swedish parliament has also decided after an investigation by the National Energy Agency (Statens Energimyndighet) that in the urban and regional planning there should be prerequisites made for an annual output of 30 TWh of electricity from wind by 2020. This can be compared to the 6.2 TWh that was produced last year (2011).

    Previous studies have shown that an increase in wind power penetration increases the need for adjustments in other power generation plants. Of these studies, none have examined how Swedish power generation plants can work together to cope with this change in operation. Therefor this is what this study was chosen to investigate. The study is based on a step-by-step model that simulates the interaction between the three main production sources in Sweden, hydro, nuclear and thermal power generation plants, and how their operation cope with an increased share of wind power.

    The results from the study confirm that a higher penetration of wind power increases the amount of adjustments in every plant. The study also shows that the hydropower adjustment capability is often sufficient to cover the primary adjustment needed. However the adjustment capability is curtailed with a high penetration of wind power because the water power more often produces near maximal and minimal production levels. For thermal and nuclear power, the results show that they are used more extensively for adjustments with higher penetration of wind power. Their total production decreases, but full production may still be needed temporarily.

  • 197. Högström, Karin
    et al.
    Olin, Malin
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Studie av grundvattnets kväveinnehåll i en bergtäkt1990Report (Other academic)
  • 198.
    Ivansson, Victor
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Effektivitet av primärenergianvändning hos värmelagringssystem: En beräkningsmodell i Simulink2018Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    A large part of society's environmental impact originates from the housing, due to inefficient buildings/energy systems and the attitude of the residents energy use. PEF is an abbreviation for primary energy factor, which tells you how much primary energy resources are used for a source. This degree project investigated heating systems combined with heat storage system for a villa, focusing on finding the highest efficiency of primary energy and simultaneously fulfill comfort temperature and hot water needs. The purpose of the work was to expand the knowledge of heating systems integrated with heat storage, in order to reduce the use of primary energy for future buildings. The aim of the work was to answer two questions:

    • Question 1: Which system solution gives the highest efficiency of primary energy use and simultaneously satisfy the heating needs?
    • Question 2: How much reduction of environmental impact provides the optimized system compared to a standard villa heating system? 

    The investigative heating systems were solar collectors and heat pumps. The heat storage systems were phase change materials, storage tank and borehole storage. A common villa heating system was determined as an air heat pump, a smaller storage tank and a supplementary electrical element. 

    The work was conducted in a literature study where information was obtained through academic books, scientific reports, authorities and appropriate websites. To answer the questions a theoretical calculation model was built in Simulink. 

    The result showed that the system combination solar collector, storage tank (with electric cartridge) and phase change materials gave the highest efficiency of primary energy use. With determination the system solution can be applied to all geographic locations where heating needs are present and solar radiation is at least as high as Central Sweden, other geography should also apply storage tank and phase change materials, but replace the solar collector.  

  • 199.
    Iverlund, Per
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Värmeväxling med torkluft från Valmets pilotmaskin TM1: Återvinning av spillvärme vid torkning av mjukpapper2014Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    There are great demands on industrial companies today to be environmentally responsible and resource-efficient. Within the paper and tissue industry a lot of energy is being used in the processes and since many years there’s been a development towards a more efficient energy use, for example by recovery of waste heat. Valmet Tissue Technology Center in Karlstad, Sweden, has a pilot tissue machine without a waste heat recovery system. This thesis was carried out to investigate the waste heat recovery potential of the pilot machine’s drying sections, being the Yankee hood and TAD cylinders. Three different concepts of the machine were studied: DCT®, NTT™ and TAD. The enthalpy and heat flows of the exhaust air from the drying sections were calculated by the air’s mass flow, temperature and humidity. To calculate the heat recovery potential the heat demand for pre-heating combustion and make-up air, heating radiator water and generating steam by using a Waste Heat Steam Generator was investigated. The heat recovery potential was calculated theoretically but also simulated using programs for real heat exchangers. Economic savings from reduced energy use and investment costs was used to calculate the payback time for each investment alternative. As a separate task the maximum district heating loads in the facility of the pilot machine was cross checked with the pilot machine activity, to clarify any relationship between them.

    The largest enthalpy was found to be in the exhaust air from the Yankee hood when running the DCT concept followed by the NTT concept. However, the largest heat flow is in the exhaust air from the first TAD cylinder. The air from the first TAD cylinder meant the largest heat recovery potential but caused big pressure drops in the heat exchanger. The Waste Heat Steam Generator cannot be used together with the pilot machine due to too low enthalpy and heat flow in the exhaust air from the drying sections.

    In general the real heat recovery potential when pre-heating combustion and make-up air is smaller than the theoretical potential. In total, heat exchange using exhaust air from the Yankee hood means the largest energy saving when pre-heating air. The real energy saving when pre-heating air using outgoing air from the Yankee hood is 55 MWh per year, meaning 4 300 kg of propane. The largest potential for heating radiator water occurs when using exhaust air from the Yankee hood when running the DCT concept followed by the NTT concept. The TAD concept means smaller heat recovery potential regardless of air from the Yankee hood or TAD cylinders is being used. In total, heat exchange using outgoing air from the Yankee hood means the largest yearly energy saving when heating radiator water, the real energy saving in district heating being 153 MWh per year.

    The economic saving when pre-heating air is 43 000 SEK per year and when heating radiator water 63 400 SEK per year. The payback time when investing in pre-heating air is 2,6 years and when heating radiator water 4,4 years.

    A relationship between running the pilot machine and big loads of district heating use can be seen. However, changing the routines of ventilation in the machine hall during trial days would probably be the easiest way to reduce the maximum loads.

  • 200.
    Jaldell, Henrik
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    Measuring Productive Performance Using Binary And Ordinal Output Variables: The Case of the Swedish Fire and Rescue Services2019In: International Journal of Production Research, ISSN 0020-7543, E-ISSN 1366-588X, Vol. 57, no 3, p. 907-917Article in journal (Refereed)
    Abstract [en]

    Fire protection is an example of a complex production process. This study measures efficiency by constructing binary and ordinal output variables from information on residential fires in Sweden about how a fire spreads from when the fire and rescue brigade arrives to when a fire is suppressed. The motivations behind this study are that there are only a few studies trying to estimate production efficiency for fire and rescue services, that data on a more detailed level is interesting for some public services, and there is a need to be able to measure efficiency differences even if only a binary or ordinal output variable is available. Using a logit random parameter model, the random effects are interpreted as efficiency differences. The conclusions are that fire and rescue services with a more flexible fire organisation with first response persons, working in collaboration with other municipalities and with larger populations are more efficient.

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