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  • 51.
    Dahlén, Pär
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Underlag till en standard för teknisk isolering2014Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Vid upphandling inom offentlig sektor eller större företag kan användandet av standarder vara ett viktigt redskap för att säkerställa att en produkt eller tjänst uppfyller de krav som verksamheten ställer när det gäller exempelvis kvalitet, kostnader och effekter på miljön. Stigande priser på energi och en ökad insikt om samhällets negativa inverkan på miljön gör att energieffektiviseringar blivit ett viktigt inslag i de allra flesta verksamheter och här kan användandet av standarder spela en viktig roll.Syftet med det här examensarbetet är att utreda hur isolering av varma och kalla rör samt ventilationskanaler kan dimensioneras optimalt så att energiförluster från dessa minimeras. Hur olika faktorer och förutsättningar påverkar vad som är en optimerad isolering måste därmed även att utredas så att konsekvenser av olika val kan kartläggas.Målet är att ta fram ett underlag som kan fungera som hjälpmedel då en ny standard för dimensionering av teknisk isolering skall tas fram av Landstingsfastigheter i Värmland. Underlaget kommer att utgöras av en beräkningsmodell som skall kunna ge tillförlitliga uppgifter om hur olika yttre faktorer samt val av isoleringsmaterial dels kan påverka vilken den nödvändiga isoleringstjockleken blir och dels visa de ekonomiska konsekvenserna. En livscykelkostnadsanalys gjordes därför för olika dimensioneringsalternativ.Arbetet resulterade i en beräkningsmodell som kan användas för att beräkna olika isoleringstjocklekar för olika typer av fall. Grundprincipen för beräkningsmodellen är att det skall gå att undersöka vilken isoleringstjocklek som behövs då en bestämd energiförlust eller temperatur på isoleringens yta skall uppnås. Isoleringen till varma rör dimensioneras för en reducerad energiförlust medan isolering till kalla rör och ventilationskanaler dimensioneras för en önskad temperatur på isoleringens yta. Livscykelkostnadsanalysen visade att dimensioneringen bör göras för en så liten energiförlust som möjligt.Ett antal olika fall undersöktes med hjälp av beräkningsmodellen. Beräkningarna visade att val av material och ytskikt kan få en betydande inverkan på hur isoleringen måste dimensioneras för att de mål som sätts för den skall uppnås. Att välja en produkt med något lägre värmeledningsförmåga kunde exempelvis minska isoleringsbehovet med nästan 20 % på större rördimensioner. Huruvida isoleringen prioriteras i ett tidigt skede av en projektering eller ej kan också få stora konsekvenser för hur stor ett systems energiförlust blir eftersom en avgörande faktor ofta är om isoleringen får plats i utrymmet. Dimensionering av isolering för kalla system som syftar till att motverka kondensutfällning på isoleringens yta visade sig innebära förhållandevis stora energiförluster. Detta tyder på att isolering av kalla installationer istället borde dimensioneras mot energiförluster.

  • 52.
    De Magistris, Federica
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Germgård, Ulf
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Beghello, Luciano
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Paper Surface Centre.
    Järnström, Lars
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Technology and Science, Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science.
    Lestelius, Magnus
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences, Paper Surface Centre. Karlstad University, Faculty of Technology and Science, Materials Science.
    Effect of calendering on the compressibility of papers made with fibre of various properties2010Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    The surface and bulk compressibility of a given paper influence its calendering, coating, surface sizing and printing properties. This study aims at a deeper knowledge of which variable affects the compressibility of paper sheets and how calendering effect different sheet properties. The pulps were characterized by their chemical compositions and physical properties. The bulk compressibility, the surface compressibility and the thickness were evaluated both before and after calendering

  • 53. De Magistris, Federica
    et al.
    Germgård, Ulf
    Karlstad University, Faculty of Technology and Science, Department of Chemical Engineering.
    Svedinger-Andersson, Maria
    Pulping to different xylan contents and its impact on the pulp quality2008Conference paper (Other (popular science, discussion, etc.))
  • 54.
    De Vin, Leo
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Mechanical and Materials Enineering.
    Solding, Petter
    Swecast.
    Ng, Amos
    Högskolan i Skövde.
    Approaches to Energy Efficiency Assessment: A State of the Art Study2009In: Energy Efficient and Low Carbon Manufacturing, Dublin: Trinity college , 2009, p. 9-16Conference paper (Other academic)
  • 55.
    Denker, Richard
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Dimensioning and control for heat pump systems using a combination of vertical and horizontal ground-coupled heat exchangers2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A model has been developed which simulates a system consisting of a horizontal and vertical ground-coupled heat exchanger connected in parallel to the same heat pump. The model was used in computer simulations to investigate how the annual minimum and mean fluid temperatures at the heat pump varied as several parameters of the combined system were changed. A comparison was also made between different control settings for fluid flow rate distribution between the two exchangers. For the case when the flow rate distribution was not controlled, the effect of viscosity differences between a colder and warmer exchanger was investigated. The short term effects of letting the vertical heat source rest during the warm summer months was then tested. Lastly, the results of the model was compared to a simple 'rule of thumb' that have been used in the industry for this kind of combined system. The results show that using a combined system might not always result in increased performance, if the previously existing exchanger is a vertical ground-coupled heat exchanger. The effects of viscosity differences on the flow distribution seems to be negligible, especially for high net flows. Controlling the fluid flow rates seems to only be worth the effort if the the pipe lengths of the two combined exchangers differ heavily. Letting the vertical ground-coupled heat exchanger rest during summer was shown to in some cases yield an increased short-term performance in addition to the already known positive long term effects. The rule of thumb was shown to recommend smaller dimensions for combination systems than the more realistic analytical model.

  • 56.
    Edin, Oscar
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Modellering och simuleringar för att analysera förbättringsmöjligheter av värmeöverföring från kondensor i en diskmaskin med värmepump2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today, the world is faced with major challenges when dealing with environmental problems and their consequences. The most critical issue on a global scale has been identified as greenhouse gas (GHG) emissions that contribute to the enhanced greenhouse effect through elevated average temperatures around the globe. A large part of GHG emissions is linked to fossil-based electricity production. Within the EU, almost half of all electricity is produced by combustion of fossil fuels such as natural gas and coal. It is therefore of great importance that this type of production is phased out, but also that the consumption of electricity by consumers is reduced.

    In the domestic appliances industry, continuous development towards more energy-efficient solutions has been happening in response to climate change threats and stiff competition in the global marketplace. In the field of dishwasher development, ASKO Appliances AB investigates the possibilities of reducing electricity consumption by their machines. A suggested solution is to supplement the machines with a heat pump for heating the wash water instead of only a conventional electrical element. Studies have shown that this method of water heating can reduce electricity consumption by up to 24%.

    The solution means that a coil-shaped condenser is placed in the bottom-well of the machine to deliver heat to the bypassed water. In this work, focus is placed on the condenser unit in the heat pump system and its geometry, with the purpose of evaluating the possibilities for improved heat transfer to the water by simulating different geometries on the condenser. In this work, the COMSOL Multiphysics software is used to create a 3D model over the system and simulate different geometries and conditions. The model is validated by comparison with experimental data. Flow simulations evaluates the emitted power of the component when changing the diameter of the condenser, pipe diameter, and increased distance between the turns (pitch) and number of turns in the coil.

    Results presented in this study show that it is possible to improve the condenser-performance in comparison to the original design, if the pipe diameter is increased. One alternative means that the number of turns on the condenser is maintained according to the original design and the diameter is increased by 3 mm, which generates a 22 % increase of heat transfer rate. A second option is to remove one turn on the condenser and increase the diameter by 4.5 mm, resulting in a 24% increased heat transfer rate.

    The analysis of increasing the distance between the turns shows that the condenser’s heat transfer decreases as the distances increase. By analyzing the flow distribution around the condenser, it has been found that this effect occurs due to the nature of the outlet, which causes large areas with low velocities around the condenser. Discussion has been made on how this can be prevented and there is good potential to conduct further studies in the matter.

  • 57.
    Ek, Malin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Resource Recovery from Wastewater Treatment at The University of British Columbia2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study is part of a larger project, where the feasibility to build a wastewater treatment plant at the University of British Columbia (UBC) Campus is investigated. The focus of this thesis is to study potential solutions for the sludge handling process, with the goal to minimize the foot print as well as to maximize the overall energy efficiency of the sludge handling process.

    Anaerobic digestion has been expressed to be the desired sludge reduction method. Anaerobic digestion of sewage sludge has shown to be a valuable stabilization method, resulting in destruction of pathogenic organisms, reduction of sludge volume and production of energy-rich biogas. However, digestion of sewage sludge is often limited by long retention times and a low overall degradation efficiency of the solids. These limiting factors are often associated with the hydrolysis step, which is the step where cell walls are ruptured and degraded, resulting in readily available organic material for the acidogenic micro-organisms, and further along biogas.

    In this study, different system solutions have been designed, with the purpose to enhance the hydrolysis step during digestion, to optimize the net energy production and the land use. The systems that have been designed and investigated include anaerobic co-digestion of sewage sludge and food waste, as well as two pretreatment methods: microwave-enhanced advanced oxidation process and thermal hydrolysis. The systems have been evaluated from perspectives important to UBC; energy, land use, greenhouse gas emissions and phosphorus recovery.

    The finding in this study does not show one clear solution that is the most favorable from all above-mentioned perspectives. However, the main goal of this study was to find the solution that results in the highest net energy production and smallest footprint. Based on the results in this study, anaerobic co-digestion without pretreatment is the recommended system. 

  • 58. Eriksson, Karl-Erik
    et al.
    Lindgren, Kristian
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Structure, Context, Complexity, Organization: Physical Aspects of Information and Value1987Book (Refereed)
    Abstract [en]

    Our universe, as a closed system, obeys the second law of thermodynamics, i.e., its entropy, its disorder, increases. Still, in the midst of this we are wit- nessing an opposite process, in which order is emerging. The picture we have is that the universe has evolved from a totally unstructured state of matter and radiation to a highly structured state. On the surface of our Earth, some of this structure takes highly sophisticated forms in living organisms and their complex interaction and in the social as well as material organization of human societies. What makes all this possible, thermodynamically, is, of course, the fact that over the universe as a whole the entropy increase is large enough to compensate for local creation of order. The aim of this book is to sketch a perspective and to present a set of concepts, which can be useful in order to describe and understand processes in which structure emerges. The word describe gives a hint that information is an important concept. Information is a general concept, which can be applied not only to the description of a system but also to the described system as well. We shall use the concept as it was introduced by Shannon in information theory. Then one may ask for the origin of structure (measured in terms of information) in the universe; one may ask how it is being transformed and how creative and destructive processesstructure formation and entropy productionare related to each other. Many ideas and concepts have been developed which make information a very flexible and versatile theoretical tool. In this book we deal with concepts and methods belonging to the lower levels in a hierarchy of information theory concepts. These concepts take into account some necessary aspects of life, including human life, but they are far from sufficient to capture the full concept of life. The ideas used in this book have been collected from many fields, but we have no ambition to review the fields from where we have picked our material, and our collection of references is not systematic. We have mixed old material with new material, elementary discussions with more advanced, in order to make the book as a whole more self-contained. Since the book has not been written for a well-defined category of readers, we hope that in this way it will be more useful. Our aim has been to sketch a perspective on the great process of structure formation going on all the time around us, and to convey some of the most basic theoretical ideas which are useful for work in this perspective.

  • 59. Eriksson, K.-E.
    et al.
    Islam, S.
    Karlsson, S.
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Optimal Development of an Economy with a Bounded Inflow of one Essential Resource Input1984In: Resources and Energy, 6, 235-258Article in journal (Refereed)
  • 60. Eriksson, K.-E.
    et al.
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Exergi (Exergy)1991In: Nationalencyklopedien, Vol. 6,Article in journal (Other academic)
  • 61. Eriksson, K.-E.
    et al.
    Månsson, Bengt
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Termodynamik1992In: Miljö från A till Ö, Höganäs: Bra Böckers Förlag , 1992Chapter in book (Other academic)
  • 62.
    Eriksson, Linnea
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    The impact of calculation methods on the gap between predicted and actual energy performance of buildings: Using a thermal simulation model of a building2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The building sector is responsible for almost a quarter of the total carbon dioxide emissions. The urgency to reduce the emissions is reflected in the stricter guidelines which have been set all over the world. To reduce the building sector’s emissions the energy consumption need to be reduced, which can be done in two ways: building new energy efficient buildings or retrofitting of current buildings. Due to the life expectancy of current building stock the largest savings before 2030 will be made through retrofits. For this reliable computational tools are required, and currently there is a gap between the predicted and actual performance of retrofitted buildings. This thesis is going to look into how the computational method is contributing to the performance gap. A building at the RMIT campus in Melbourne, Australia, which is going to be retrofitted through retrofits designed by Siemens, is used. A thermal simulation model of the building was built, and tuned to reflect the pre-retrofit building, and compared against the measured energy performance of the building. The retrofits were then implemented in the simulation model and the gap in the predictions between the simpler computational method used by Siemens in designing the retrofits, and the extensive simulation model was compared. The gap between the computational methods were analysed in order to see how Siemens calculation method contribute to the performance gap. The conclusions which have been drawn are that the simulation model is reflecting the energy use of the building well considering the access of data available during the study. Especially the electricity use is reflected well both in the total annual use, approximately 4 % gap to measured value, and the monthly variation over the year. The total natural gas use is under predicting the annual use, approximately 40 % gap to the measured value, but shows a good correlation to the monthly variation. The electricity use is relatively stable in the simulation model, where the natural gas was sensitive for direct changes to the heating system. The input parameters which have the largest impact in the electricity use are internal gain profiles and the electrical internal gains energy use. Siemens calculation method are contributing to the performance gap through the lack of interaction between the different retrofits, the light retrofit have a noticeable impact on the heating and cooling system of the building. To only use one single period in the regression models can also easily lead to incorrect predictions. The strength of the simulation model is its ability to see the retrofits influence on each other and the possibility for scenario analysis.

  • 63.
    Eriksson, Viktor
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Energikartläggning av ett mjukpappersbruk: Värmeåtervinning som alternativ till ånga för uppvärmning av lokaler2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The pulp and paper industry in Sweden accounted for 51% of the Swedish industrial sector's total energy consumption in 2015. This makes it particularly important for the Swedish pulp and paper industries to document their energy on a regular basis to identify where and how energy is used, a so-called energy audit. This allows for the weaknesses in the system to be identified and measures to fix them can then be developed.

    This study was performed on Katrinefors mill, which is located in Mariestad and is one of three tissue mill that the group Metsä Group has in Sweden. Katrinefors mill uses both recycled fiber and virgin wood fibers to produce tissue paper in the form of toilet paper and paper towels among others.

    An energy audit on Katrinefors mill was performed where the mill's total energy consumption in 2015 was identified by analyzing Excel documents used by the mill to document their energy usage.

    The heat recovery system for the wet air from one of the paper machines Yankee hoods was also studied to see if additional energy could be extracted from one of the heat exchangers for use in the heating system. The mass flow of air and water through the Yankee hood was calculated using mass balances. The energy content in the air at different positions in the heat recovery system was established using energy- and mass balance calculations together with dry- and wet bulb temperature measurements. Calculations were performed for the amount of water that would be required to humidify the air to a saturated state. It was assumed that if the air were to be saturated that the heat transfer in the heat exchanger would increase due to a higher rate of condensation.

    The energy audit showed that the paper machines and deinking plant was the mill's largest energy users. It also showed that the improvements made at the mill since 2010 have led to a steadily declining energy usage per ton of paper produced per year.

    The results of the calculations regarding the heat recovery shows that the energy content of the air would suffice to cover the heating of all buildings that otherwise would rely on steam. The results show, however, that the heat exchanger studied probably is not big enough and that it would need to be supplemented or replaced by a new heat exchanger.

    The actions developed in this study could still be possible to implement without supplementing or replacing the existing heat exchanger. This requires a further study investigating the heating requirements for the each building individually to see if a portion of the total heating could be covered by the measures presented in this study.

  • 64. Fanting, Gong
    Linking socio-economic factors to urban growth by using night timelight imagery from 1992 to 2012: A case study in Beijing2015Other (Other academic)
    Abstract [en]

    In recent decades, the night lights data of the Earth’s surface derived from the Defense Meteorological Satellite Program’s Operational Linescan System (DMSP/OLS) have been used to detect the human settlements and human activities, because the DMSP/OLS data is able to supply the information about the urban areas  and non-urban areas on the Earth which means it is more suitable for urban studies than usual satellite imagery data.   The urban development is closed linked to the human society development. Therefore, studies of urban development will help people to understand how the urban changed and predict the urban change. The aim of this study was to detect Beijing’s urban development from 1992 to 2012, and find the contributions to the urban sprawl from socio-economic factors. Based on this objective, the main dataset used in this thesis was night lights images derived from the DMSP/OLS which was detected from  1992 to 2012. Due to the lacking of on-board calibration on OLS, and the over-glow of the lights resources, the information about the night lights cannot be extracted directly. Before any process, the night lights images should be calibrated. There is a method to calibrate the night light images which is called intercalibration. It is a second order regression model based method to find the related digital number values. Therefore, intercalibration was employed, and the threshold values were determined to extract urban areas in this study. Threshold value is useful for diffusing the over-glow effect, and finding the urban areas from the DMSP/OLS data. The methods to determine the threshold value in this thesis are empirical threshold method, sudden jump detection method, statistic data comparison method and k-mean clustering method. In addition, 13 socio-economic factors which included gross domestic product, urban population, permanent population, total energy consumption and so on were used to build the regression model. The contributions from these factors to the sum of the Beijing’s lights were found based on modeling.   The results of this thesis are positive. The intercalibration was successful and all the DMSP/OLS data used in this study were calibrated. And then, the appropriate threshold values to extract the urban areas were figured out. The achieved urban areas were compared to the satellite images and the result showed that the urban areas were useful. During the time certain factors used in this study, such as mobile phone users, possession of civil vehicles, GDP, three positively highest contributed to urban development were close to 23%, 8% and 9%, respectively.

  • 65. Fones, G.R.
    et al.
    Davison, W.
    Holby, Ola
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Jørgensen, B.B.
    Thamdrup, B
    High-resolution metal gradients measured by In Situ DGT/DET deployment in Black Sea sediments using an autonomous benthic lander2001In: Limnol. Oceanogr. 46(4):982-988Article in journal (Refereed)
  • 66.
    Forsberg, Jan
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Tidsserieanalys av data från Sjöfartsverkets mätstationer i Vänern: En förstudie om seicher och uppstuvning i Vänersborgsviken2012Report (Other academic)
    Abstract [sv]

    Denna studie är finansierad av Centrum för klimat och säkerhet och har utförts vid avdelningen för Energi-, miljö- och byggteknik under 2011 - 2012. Barbara Blumenthal och Lars Nyberg vid Centrum för klimat och säkerhet har varit beställare och värdefulla diskussionspartners i studien.

    Förväntade klimatförändringar och kommunernas planer att bygga nära vatten förutsätter kunskaper om extrema nivåer i Vänern, i dess tillflöden och om extrema nivåers verkan på samhället. Sedan lång tid finns dygnsmedelvärden för nivån i Vänern, men ännu saknas kunskaper om nivåns rörelser i timskala. Fenomen som seicher och uppstuvning i Vänern uppträder i denna tidskala. Vid extrema dygnsmedelnivåer adderas riskerna från timvariationer i Vänerns nivå. Riskerna varierar från plats till plats.

    Under hösten 2011 har en av Sjöfartsverkets mätstationer i Vänern kompletterats med vindmätare. Stationen är placerad vid Dalbobron i Vänersborg och registrerar samtidig vindhastighet, vindriktning och vattennivå var tionde minut. Detta har gjort det möjligt att studera timvariationer i vattennivån i Vänersborgsviken, vars form förstärker uppträdande seicher och uppstuvningar. Studien visar att enkla bassängmodeller kan användas för att beräkna periodtiden hos möjliga seicher. Ett mindre antal tidsserieanalyser visar också på möjligheten att använda mätstationens data för att göra prognoser någon timme framåt i tiden, för den lokala nivån. Vid ett tillfälle under våren 2012 ändrades nivån 75 cm på mindre än 6 timmar vid vindstyrkor på 13 m/s, d.v.s. utan att vädret var extremt.

    Mätstationernas information tillåter enbart lokala nivåprognoser. För prognoser på en valfri plats vid Vänern krävs det förmodligen en dynamisk bassängmodell för Vänern och som utnyttjar informationen från mätstationerna.

  • 67.
    Forsberg, Åsa
    Karlstad University, Faculty of Technology and Science.
    Energieffektivisering i ett verkstadsföretag: En analys av energibesparande åtgärder samt uppvärmnings- och kylsystems driftkostnader och koldioxidutsläpp2010Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The energy use in a workshop company has been examined in this work in order to find areas for energy efficiency improvement. The combined oil and electricity heating in the company were compared with other alternative heating systems including cooling of the premises in following combinations:

    1. Ground source heat pump for heating and cooling
    2. District heating and absorption cooling
    3. District heating and low temperate surface water cooling

    Energy use, operation costs and carbon dioxide emissions were calculated for the current heating systems and the three alternatives including cooling. The ground source heat pump for heating and cooling decreases bought energy with 34 MWh annually compared to current heating only. The district heating and low temperate surface water cooling has the largest reduction of operation cost and carbon dioxide. The operation cost decreases with 42 kSEK and the carbon dioxide with 43 metric ton CO2 annually. The differences between the alternatives were smaller concerning the operation costs. The ground source heat pump alternative had smaller reductions of carbon dioxide than the other two alternatives with district heating.

    An alternative heating and cooling system can also lead to alternative energy use. The choice is between electrical or heat energy. A weighting can be done to evaluate the energy use for heating on basis of how much energy is needed in order to generate the energy the end user buys. A 2.5 factor for electrical energy entails the alternative with district heating and low temperate surface water cooling gets the lowest heating and cooling energy in comparison.

    An inventory of the lighting was also done. The company has already an energy effective lighting but yet another saving of 2 MWh can be done annually without replacement of armatures.

    Finally, the operation time of the compressor was calculated with a mean value of 11 hours per day. The compressor delivers pressure air to machines and tools. There can be a great demand for pressure air in the workshop but the operation time can also be an indication of leakage in the air net.

  • 68.
    Fredriksson, Emma
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Effektiviserad avkylning av fjärrvärmevatten: En studie om kundanläggningarnas påverkan på returtemperaturen2014Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Having a low return temperature and high cooling of the district heating water is something the district heating companies constantly pursues. Lower network temperatures is beneficial both in terms of efficiency and economy, as, for example, distribution losses and pump power decreases. The amount of cooling is affected by several factors, both in the distribution network and in the customer facilities. Commissioned by Kils Energi AB (KEAB) this thesis aimed to investigate how to improve the cooling in Kil´s district heating network, and focused on the extent to which the customer facilities affects the cooling.

     It has been identified, by using a method called the overconsumption principle, the customer facilities that increases the return temperature most during different periods during the year of 2012. The principle describes the extra amount of water volume consumed compared to what should be consumed if the cooling ambition is achieved. The results shows that costumer facilities with high energy use and fluid consumption affects the return temperature most. The cooling in the network would improve by several degrees if those facilities would function optimally. For example, the facility 48 had the highest overconsumption during January 2012, and if the facility had reached the cooling ambition of 50°C the total return temperature could have been reduced by about 2°C. The 5 costumer facilities with the highest annual overconsumption was examined to see why they did not meet the cooling ambition. The errors that can lead to an increased return temperature could be traced to the customer plants´ internal heating- and domestic hot water circuit, the secondary circuit. For example, a manual three-way valve was discovered that was fully open which short-circuited the flow. Since the costumers of KEAB are responsible and owns the secondary circuit, the work to increase efficiency in the system is obstructed, because there are no financial incentives in the current situation from the customer's part to make any improvements. Furthermore, customers generally lack knowledge of how energy efficient the facility in question is. Therefore it is recommended that KEAB introduces a flow-based fee combined with information dissemination to customers so that they understand the importance of making improvements. 

    It was examined the potential gain when the total return temperature in the network was lowered 1-5°C, with the boundary to only examine the profit when the distribution losses are reduced. If the return temperature was lowered 5°C the distribution losses would decrease by 4,2 %. That would lead to an estimated profit of 53 100 SEK.    

     

    Conclusions to be drawn from the thesis is that an improved cooling/return temperature in Kil´s district heating system can lead to an increased efficiency in the network and lower costs for the heating company. The biggest challenge to improve the cooling will be getting the costumers to make improvements in the secondary circuit. 

  • 69.
    Frodeson, Stefan
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Berghel, Jonas
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Renström, Roger
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    The potential in using two step drying techniques for improving energy efficiency and increasing the drying capacity in fuel pellet industries2012In: Drying Technology, ISSN 0737-3937, E-ISSN 1532-2300, Vol. 31, no 15Article in journal (Other academic)
  • 70.
    Frodeson, Stefan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Berghel, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Ståhl, Magnus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Romlin, Carl
    Drinor AB, Karlstad.
    Thelander, Alexander
    Drinor AB, Karlstad,.
    The Potential for a Pellet Plant to Become a Biorefinery2019In: Processes, ISSN 2227-9717, Vol. 7, no 4, p. 1-11, article id 233Article in journal (Refereed)
    Abstract [en]

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

  • 71.
    Frodeson, Stefan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Henriksson, Gunnar
    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).
    Effects of moisture content during densification of biomass pellets, focusing on polysaccharide substances2019In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 122, p. 322-330Article in journal (Refereed)
    Abstract [en]

    In this study, we pelletized four different pure polysaccharides represented cellulose - Avicel, hemicelluloses - locus bean gum mannan and beech xylan and other polysaccharides - apple pectin, and three woods - pine, spruce and beech. All were pelletized at 100° in a single pellet press unit with different level of moisture content from 0 to 15%. The maximal friction force and work required for compression and friction was analyzed together with the pellet density and hardness. The results showed that xylan pellets completely changed in color at 10% moisture content, and this also occurred to some extent with pectin pellets. The color of both Avicel and locus bean gum pellets were not affected at all. During compression, the results showed that water does not affect compression up to 5 kN, while above 5 kN water decreases the energy need for densification of Avicel, locus bean gum and woods. Above 5 kN the energy needs for compressing xylan and pectin increases with increased moisture content. The hardest pellets were produced from Avicel, while locus bean gum produced the weakest pellets. The study concludes that there is a significant difference in how water affects the two hemicelluloses, glucomannan and xylan, during densification.

  • 72.
    Frodeson, Stefan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Henriksson, Gunnar
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Berghel, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Pelletizing pure biomass substances to investigate the mechanical properties and bonding mechanisms2018In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 13, no 1, p. 1202-1222Article in journal (Refereed)
    Abstract [en]

    Solid fuel for heating is an important product, and for sustainability reasons, it is important to replace nonrenewable fuels with renewable resources. This entails that the raw material base for pellet production has to increase. A broader spectrum of materials for pelleting involves variation in biomass substances. This variation, due to lack of knowledge, limits the possibilities to increase the pellet production using new raw materials. In this study, pellets were produced with a single pellet press from 16 different pure biomass substances representing cellulose, hemicellulose, other polysaccharides, protein, lignin, and extractives, and five different wood species, representing softwoods and hardwoods. All pellets were analyzed for the work required for compression and friction, maximum force needed to overcome the backpressure, pellet hardness, solid density, and moisture uptake. The results showed that the hardest pellets were produced from the group of celluloses, followed by rice xylan and larch arbinogalactan. The weakest pellets were from the group of mannans. Conclusions are that the flexible polysaccharides have a greater impact on the pelletizing process than previously known, and that the differences between xylan and glucomannan may explain the difference in the behavior of pelletizing softwoods and hardwoods.

  • 73.
    From-Aldaron, M.
    et al.
    Karlstad University.
    Sandberg, Maria
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Granström, Karin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Low Dosage Chemical Treatment for Improved Oxygenation of Pulp Mill Effluents2018In: Journal of environmental engineering, ISSN 0733-9372, E-ISSN 1943-7870, Vol. 144, no 3, article id 06017012Article in journal (Refereed)
    Abstract [en]

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

  • 74.
    Garcia Lawson, David
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Produktion av näringspellets med varierad mekanisk kraft och ligninhalt: Utvärdering av pelletsegenskaper och energianvändning2019Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Continued increase in carbon dioxide emissions lead the ecosystems towards rapid, dangerous and irreversible climate change. The Swedish forest industry is an important operator to satisfy the future demand of renewable bio products to reduce the use of fossil fuels. The increase in production means increased pressure on the Swedish forests. Society, government, companies and individuals have a responsibility to secure that the harvesting of forests remains sustainable.

    The wastewater treatment plants in the pulp and paper industry produce a large proportion of biomass, in form of bio and fiber sludge. Bio and fiber sludge contains nutrients that can be returned to the forest. The upgrade of biomass to pyro-char has proven properties that improve the fertility of the forest, primarily by increasing the soil's pH value. Pyro-char improves the retention of nutrients in the soil by cation adsorption, which affects the trees and plant growth. The composition of the soil changes as pyro-char is added, and the change in composition affects the biodiversity in ecosystems. The biofuel ash extracted from the heating boilers in the paper industry contains basic cations and alkaline pH, which counteracts acidification in forest land.

    The disadvantage of biomass is the high bulk density, which affects the logistics of transport and storage. There are methods for solving the problems in logistics, for example compression. Compression is a well-proven method for upgrading the biomass to pellets and improving the physical properties of the biomass. The conversion of biomass into pellets increases the density, mechanical strength and the moisture absorption capacity decreases. Pelletizing biomass results in a homogeneous product can be created and delivered as pellets.

    The purpose of this study is to increase the knowledge on how lignin as an additive, and how mechanical force affects the physical properties of the nutritional pellets. The production of nutrition pellets consists of two stages, a preliminary investigation and a test matrix. The purpose of the preliminary study is to acquire guideline values ​​and provide a basis for the experimental matrix. The experimental matrix is ​​a continued study of how lignin content and pressure affect the physical properties of the nutrition pellet. The lignin content that was analyzed was 5-20 % with mechanical force that varied between 5, 10 and 15 kN. The nutritional pellets are evaluated based on the properties density, hardness, pH, moisture absorption capacity and energy use.

    The single-pelletizer press, located at Karlstad University, was used to pelletize the different mixtures. The pellet properties were evaluated at the laboratory at Karlstad University.

    The result shows that the test series with a pressure of 15 kN and the lignin content of 20% resulted in the highest density, hardness, moisture absorption capacity and the second highest energy consumption. Depending on the mechanical force and lignin content used, the parameters varied as follows.

    • The density varies between 843.5 – 1,054 kg/m3
    • The hardness ranged between <1 and 3.7 kg
    • The moisture content of the pellets varied between 8.7% and 9.2% after 96 hours
    • The pH-value varied between 8.7-9.58 after 24 hours and decreased between 2- 4.9 % after 48 hours
    • The energy consumption varies between 105.5-129.5 J

  • 75.
    Gewert, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Datormodellering av en värmelagrande konstgräsplan: En temperaturstudie över ett år för en uppvärmd konstgräsplan2013Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    In Skattkärr has a heated turf field been projected to enable activities during the winter when snow and cold weather put a stop to activities in an unheated turf field. In Skattkärr it’s not possible to connect the system to a district heating network. The technique chosen to heat the field is instead a type of geothermal energy where PVC-pipes are located beneath the artificial turf’s surface. Next to the the field is a total of 31 boreholes located. From those boreholes heat is collected from the mountain and headed out to a coil under the plan. Unlike conventional geothermal, there is no use of a heat-pump. Instead the system in Skattkärr uses the natural heat from the soil, approximately 7 ° C. It is expected to be enough to keep snow and ice away from the artificial turf field. In summer when there is no need of heating, the fluid in the tubes is heated. This heat can later on be stored in the ground for the winter season. The field may, in other words, in principle, be regarded as a solar collector. The system's operating cost is therefore the circulation-pump. The operation itself is projected to be intermittent. This means that the system is expected to stand still until the need for heating or cooling. The system is then turned off when the need for heating or cooling is ceased.

    The aim of this work is to investigate how an artificial turf field can be heated and cooled optimally without becoming unusable due to its surface temperature. The goal of this work is to create a mathematical model of the system that describes the temperature on the artificial turf's surface.

    To study the artificial turf field's surface temperature is a mathematical model created, whose mission is to dynamically analyze energy flows over time. The model is built in Simulink, a part of MATLAB. The model of artificial grass field consists of several partial measurement exercises in turn gives different energy flows. The plan considered in the balance as a slab with a heat store. This allows generalizations to be made to facilitate various calculations with equations applied to slabs on ground.

    The result shows that the heating system has difficulties to heat the field to temperatures demanded during winter. Instead, the surface temperature follows the current air temperature, like an unheated field. Unfortunately, there is lack of knowledge about the flow conditions and fluid temperature in the pipe loop system. Therefore, further work to ensure these factors are needed. Only then can an arbitrary basis for the circulation pump control be presented.

  • 76.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences. Norwegian University of Science & Technology.
    A critique of the European Green City Index2014In: Journal of Environmental Planning and Management, ISSN 0964-0568, E-ISSN 1360-0559, Vol. 57, no 3, p. 317-328Article in journal (Refereed)
    Abstract [en]

    In 2009, Siemens (Germany) sponsored the research by the Economist Intelligence Unit (London), which resulted in the publication of the European Green City Index report, in which the environmental performance of 30 large cities in Europe was analysed. It provided city administrations with an idea of where they stood vis-a-vis their European counterparts. However, while adopting such performance evaluation methodologies, it is important to set targets and goals, and to be aware of pitfalls that may exist in the course of a blind pursuit of a higher Green Score. City administrations are usually segmented into different divisions and departments; often each division strives towards its own set of targets and goals, without being aware (or without being concerned, even if it is aware) of the overlaps, conflicts and synergies that may exist with the targets and goals of the others. The Green City Index needs to be considered together with an Urban Socio-Economic Index, which can be suitably structured with the inter-linkages with the indicators of the Green City Index explicitly described.

  • 77.
    Govindarajan, Venkatesh
    Norwegian University for Science & Technology, Norway.
    ABC of Sustainable Development2015 (ed. 1)Book (Refereed)
    Abstract [en]

    Sustainable development is a field of thought, learning, research and endeavour, which has entrenched itself in the 21st century. This book is certainly very very far from being the be-all and end-all of knowledge about sustainability and sustainable development, as readers will appreciate. This modest effort is something which I hope provides some food for thought…and then hopefully, purposeful action. This book is about 90 pages long, and is split up into 9 chapters, and dwells on the different aspects of sustainable development and the challenges associated with integrating these so that development is truly and holistically sustainable….Chapters begin with Learning Objectives which at once tells the reader what to expect from it, and some Exercises at the end, which one may wish to attempt, en route.

    As Prof Genon Giuseppe from Turin, Italy, in the Foreword to the book, says, ‘This book is useful to university curricula, aimed at grooming professionals capable of considering all the aspects of sustainable development and of course, can very well be integrated into a host of academic disciplines, as the author has pointed out in one of the chapters.’

    As Dr Håvard Bergsdal from Trondheim, Norway, says, in his review comments, ‘The book makes for good reading and serves as a useful summary for readers who are new to the topic of sustainability.’

  • 78. Govindarajan, Venkatesh
    Analysis of stocks and flows in Indian households, associated with water consumption2013In: Journal of Industrial Ecology, ISSN 1088-1980, E-ISSN 1530-9290, Vol. 17, no 3, p. 472-481Article in journal (Refereed)
  • 79. Govindarajan, Venkatesh
    Changes in material flows, treatment efficiencies and environmental load-shifting in the wastewater treatment sector Part II: Case study of Norway2009In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 30, no 11, p. 1131-1143Article in journal (Refereed)
  • 80.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Classroom survey to gauge how the three pillars of sustainability are prioritised for the urban water and wastewater system2017In: Vatten, ISSN 0042-2886, Vol. 73, no 1, p. 33-37Article in journal (Other academic)
  • 81.
    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.         

  • 82.
    Govindarajan, Venkatesh
    Norwegian University for Science & Technology, Norway.
    Economic impact of upgrading biogas from anaerobic digesters to biomethane for use as transportation fuel: Case study of Bekkelaget Wastewater Treatment Plant in Oslo, Norway2014In: Sewage Treatment plants: Economic evaluation of innovative technologies / [ed] Katerina Stamatelatou, Konstantinos P. Tsagarakis, London, UK: IWA Publishing, 2014, 1Chapter in book (Refereed)
  • 83.
    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)
  • 84.
    Govindarajan, Venkatesh
    Norwegian University for Science & Technology, Norway.
    Environmental systems analysis of urban water systems - limited historical account of published work in scientific journals2015In: Vatten, ISSN 0042-2886, Vol. 71, no 4, p. 209-222Article in journal (Other academic)
  • 85.
    Govindarajan, Venkatesh
    Norwegian University for Science & Technology, Norway.
    Future prospects of industrial ecology as a set of tools for sustainable development2012In: Problemy Ekorozwoju, ISSN 1895-6912, E-ISSN 2080-1971, Vol. 7, no 1, p. 77-80Article in journal (Refereed)
  • 86.
    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.  

     

  • 87.
    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)
  • 88.
    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). 

  • 89.
    Govindarajan, Venkatesh
    Norwegian University of Science, Oslo, Norway.
    Triple bottom line approach to individual and global sustainability (Translated into Polish).2010In: Problemy Ekorozwoju, ISSN 1895-6912, E-ISSN 2080-1971, Vol. 5, no 2, p. 29-37Article in journal (Other academic)
    Abstract [en]

    Industrial ecology is founded on analogies and lateral thinking, borrowing and adapting, and opening up the frontiers of imagination and innovativeness to make the road to sustainable development more tractable. Talking of the key role mankind needs to play to make sustainable development a reality, a wonderful analogy is uncovered – between holistic individual human development and the triple bottom line approach (economic, social and environmental) to sustainable progress of humanity as a whole on the surface of the earth. An individual starts off from gross materialism (body) but needs to aim for the right blend of physical, emotional and spiritual advancement in life. When all individuals do so, a lop-sided socio-economic techno-sphere will gradually metamorphose into a fully-evolved one. Paradoxically, individuals need to delve in and comprehend their spiritual selves, for the technosphere to fan out and embrace the earth of which it is just a small component.

  • 90. Govindarajan, Venkatesh
    Typifying cities to streamline the selection of relevant environmental sustainability indicators for urban water supply and sewage handling systems2013In: Environment, Development and Sustainability, ISSN 1387-585X, E-ISSN 1573-2975, Vol. 15, no 3, p. 765-782Article in journal (Refereed)
  • 91.
    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.

  • 92.
    Govindarajan, Venkatesh
    et al.
    Norwegian University of Science and Technology, Trondheim, Norway.
    Brattebo, Helge
    Norwegian University of Science and Technology, Trondheim, Norway.
    Changes in material flows, treatment efficiencies and shifting of environmental loads in the wastewater treatment sector.: Part I: Case study of the Netherlands2009In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 30, no 11, p. 1111-1129Article in journal (Refereed)
    Abstract [en]

    The material that is separated from wastewater in wastewater treatment plants has to be transferred from the water phase to the atmosphere, lithosphere, and/or biosphere (and also the technosphere). After the initial discharges into the different environmental media (and the technosphere), there are further 'inter-sphere' leakages or redirections. However, these happen over protracted periods of time and have not been accounted for in this paper. The paper presents a case study on the wastewater treatment plants in the Netherlands, examines how the degree of separation of COD (BOD), nitrogen, phosphorus and heavy metals from the wastewater have increased over time, and studies the changes in proportions separated out to the atmosphere and lithosphere. The hydrosphere has benefited from a decline in the degree of eutrophication and marine/fresh water toxicity, owing to the favourable combination of higher degrees of separation, over time, and source control, especially in the industrial sector. Global warming is a major concern owing to the increasing conversion of COD to carbon dioxide (and methane). Heavy metal and nitrogen emissions have been curbed thanks to source reduction within industries. Technologies have, of course, enabled some mitigation of the problems associated with atmospheric (global warming and toxicity) and lithospheric (toxicity) pollution, though these are beyond the scope of this paper, which assumes a hypothetical worst-case scenario in this regard for the study period 1993-2005.

  • 93.
    Govindarajan, Venkatesh
    et al.
    Norwegian University for Science & Technology, Norway.
    Brattebo, Helge
    Norwegian University for Science & Technology, Norway.
    Environmental impact analysis of chemicals and energy consumption in wastewater treatment plants: Case study of Oslo, Norway2011In: Water Science and Technology: Water Supply, ISSN 1606-9749, E-ISSN 1607-0798, Vol. 63, no 5, p. 1081-1031Article in journal (Refereed)
  • 94.
    Govindarajan, Venkatesh
    et al.
    Norwegian Univ Sci & Technol, Dept Hydraul & Environm Engn, N-7491 Trondheim, Norway.
    Brattebo, Helge
    orwegian Univ Sci & Technol, Energy & Proc Engn Dept, Ind Ecol Programme, N-7491 Trondheim, Norway.
    Studying the demand-side vis-a-vis the supply-side of urban water systems - Case study of Oslo, Norway2014In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 35, no 18, p. 2322-2333Article in journal (Refereed)
  • 95.
    Govindarajan, Venkatesh
    et al.
    Norwegian University for Science & Technology, Norway.
    Chan, Arthur
    NTNU, Energy & Proc Engn Dept, N-7491 Trondheim, Norway.
    Brattebo, Helge
    Norwegian University for Science & Technology, Norway.
    Understanding the water-energy-carbon nexus in urban water utilities: Comparison of four city case studies and the relevant influencing factors2014In: Energy Journal, ISSN 0195-6574, E-ISSN 1944-9089, Vol. 75, no 1, p. 153-166Article in journal (Refereed)
  • 96.
    Govindarajan, Venkatesh
    et al.
    Norwegian University for Science & Technology, Norway.
    Dhakal, Shobhakar
    Natl Inst Environm Studies, Global Carbon Project, Tsukuba, Ibaraki, Japan.
    An international look at the water-energy nexus2012In: Journal of American Water Works Association, ISSN 0003-150X, Vol. 104, no 5, p. 93-96Article in journal (Other (popular science, discussion, etc.))
  • 97.
    Govindarajan, Venkatesh
    et al.
    Norwegian Univ Sci & Technol, Dept Hydraul & Environm Engn, N-7491 Trondheim, Norway.
    Elmi, Rashid Abdi
    Economic-environmental analysis of handling biogas from sewage sludge digesters in wastewater treatment plants for energy recovery: Case study of Bekkelaget wastewater treatment plant in Oslo, Norway2013In: Energy Journal, ISSN 0195-6574, E-ISSN 1944-9089, Vol. 58, no 10, p. 220-235Article in journal (Refereed)
  • 98.
    Govindarajan, Venkatesh
    et al.
    Norwegian university of science and technology, Trondheim, Norway.
    Hammervold, Johanne
    Brattebo, Helge
    Norwegian university of science and technology, Trondheim, Norway.
    Combined MFA-LCA for analysis of wastewater pipeline networks: Case study of Oslo (Norway).2009In: Journal of Industrial Ecology, ISSN 1088-1980, E-ISSN 1530-9290, Vol. 13, no 4, p. 532-550Article in journal (Refereed)
    Abstract [en]

    Oslo's wastewater pipeline network has an aging stock of concrete, steel, and polyvinyl chloride (PVC) pipelines, which calls for a good portion of expenditures to be directed toward maintenance and investments in rehabilitation. The stock, as it is in 2008, is a direct consequence of the influx of pipelines of different sizes, lengths, and materials of construction into the system over the years. A material flow analysis (MFA) facilitates an analysis of the environmental impacts associated with the manufacture, installation, operation, maintenance, rehabilitation, and retirement of the pipelines. The forecast of the future flows of materials-which, again, is highly interlinked with the historic flows-provides insight into the likely future environmental impacts. This will enable decision makers keen on alleviating such impacts to think along the lines of eco-friendlier processes and technologies or simply different ways of doing business. Needless to say, the operation and maintenance phase accounts for the major bulk of emissions and calls for energy-efficient approaches to this phase of the life cycle, even as manufacturers strive to make their processes energy-efficient and attempt to include captive renewable energy in their total energy consumption. This article focuses on the life cycle greenhouse gas emissions associated with the wastewater pipeline network in the city of Oslo.

  • 99.
    Govindarajan, Venkatesh
    et al.
    Norwegian University for Science & Technology, Norway.
    Saegrov, Sveinung
    Norwegian University for Science & Technology, Norway.
    Brattbo, Helge
    Norwegian University for Science & Technology, Norway.
    Dynamic metabolism modelling of urban water services - demonstrating effectiveness as a decision-support tool for Oslo, Norway2014In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 61, no 1, p. 19-33Article in journal (Refereed)
  • 100.
    Granberg, Johan
    Karlstad University, Faculty of Technology and Science.
    Material- och energiåtervinning av kuvert: Scenarioanalys2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Recycling and incineration are two ways to deal with waste. Generally, paper recycling has lower carbon dioxide emissions than incineration of paper. Envelope is a paper product that is not included in any producer responsibility and the pulp and paper industry recommends consumers not to sort envelopes in the paper recycling container, since envelopes contain substances that can be a source for stickies. An argument against recycling is that problems caused by stickies increases costs for the companies that produces paper from waste paper. The Swedish market has envelopes that, when they are processed in the paper mill, do not develop stickies, namely envelopes tagged with Svanen. The purpose of this paper is to find the most suitable way to deal with envelopes. The aim of this study is to find the net energy consumption for recycling and incineration of envelopes. Four scenarios were investigated; all envelopes are incinerated, all envelopes are recycled, only envelopes tagged with Svanen are recycled, all envelopes are replaced with envelopes tagged with Svanen and are recycled. The results are not unanimous. Replacing all envelopes with envelopes tagged with Svanen is the scenario with lowest net energy consumption, presupposed paper recycling is to prefer before paper incineration.

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