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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Ammonium removal from municipal wastewater with application of ion exchange and partial nitritation/Anammox process

Malovanyy, Andriy January 2014 (has links)
Nitrogen removal from municipal wastewater with application of Anammox process offers cost reduction, especially if it is combined with maximal use of organic content of wastewater for biogas production. In this study a new technology is proposed, which is based on ammonium concentration from municipal wastewater by ion exchange followed by biological removal of ammonium from the concentrated stream by partial nitritation/Anammox process. In experiments on ammonium concentration four the most common ion exchange materials were tested in packed bed columns, namely strong and weak acid cation exchange resins, natural and synthetic zeolites. Experiments with synthetic wastewaters with different content and municipal wastewater showed that strong acid cation resin is the most suitable for ammonium concentration from municipal wastewater due to its high exchange capacity and fast regeneration. Since NaCl was used for regeneration of ion exchange materials, spent regenerant had elevated salinity. Experiments with activity determination showed that both nitritation and Anammox bacteria are inhibited by NaCl, where effect on Anammox bacteria is more severe. Adaptation of partial nitritation/Anammox biomass was studied using two strategies of salinity increase and it was possible to adapt the biomass to NaCl content of 10-15 g/L. The technology was tested in batch mode using strong acid cation resin for ammonium concentration from pretreated municipal wastewater, and partial nitritation/Anammox biomass for nitrogen removal from concentrated stream. It was shown that it is possible to remove 99.9% of ammonium from wastewater with ion exchange while increasing concentration of ammonium in spent regenerant by 18 times. Up to 95% of nitrogen from spent regenerant was removed by partial nitritation/Anammox biomass in batch tests. Moreover, possibilities of integrati on of the technology into municipal wastewater treatment technology, challenges and advantages were discussed. / <p>QC 20140219</p>
52

A Study on Life Cycle Assessment-based Tool for the Early Stage of Building Design

Ravan, Nazila January 2019 (has links)
The responsibility of the building sector to diminish the harmful environmental impacts, locally and globally, has been extensively considered. Thus, Environmental Impact Assessment (EIA) in building and construction practices has been widely implemented. Among several available EIA methods, Life Cycle Assessment (LCA) is the only standardized method which provides a holistic overview of environmental impacts to support the decision-making process. However, there are several barriers that hinder the process of implementing the LCA-based tools in the building sector. Specifically, the demand for a simplified LCA-based tool adapted to the early stage of the building design is rather high. Recently, the Construction Sector's Environmental Calculation Tool (Byggsektorns Miljöberäkningsverktyg BM v1.0) is developed to assist non-experts without knowledge of LCA. Architects, as one of the main target groups of the BM tool, have limited knowledge about the LCA approach due to its complexities; further, the architects have their own requirements for applying an LCA-based tool towards leveraging in the early design process. Hence, it leads to scepticism whether the BM tool has been so far successful to entice the architects' attention towards employing the BM tool in that process. This master thesis aimed to investigate if the newly-developed LCA-based tool, namely the BM tool, is a desirable choice for architects to evaluate the environmental impacts of their design at the early stage of building design. To be able to perceive more deeply the BM tool, as an environmental assessment and a decision support tool for architects, two main procedures, i.e., quantitatively and qualitatively, were employed to cover different technical and functional angles of the tool: (i) an LCA-based carbon footprint assessment for two reference buildings along with comparing the achieved results with the simplified Environmental Load Profile (ELP-s) tool, plus (ii) using a framework included various criteria for LCA- based tools in the early stage of building design. The findings from the quantitative analysis were consistent so that the concrete frame building produces a greater amount of carbon footprint during the stages A1 to A4 compared to the wooden frame building. The considerable deviation was related to the carbon footprint of aluminium profile in the material production stage. This could be due to the fact that in the BM database it is not specified whether aluminium profile was recycled or not. Regarding the carbon footprint in material transport stage, the inconsistent results were mostly linked to the default values in the BM database in which values for two of the main parameters (distance and mode of transport) differed. Particularly, the absence of boat as a transport mode and an error related to an unneeded distance value for concrete transport were identified in the BM database. The framework, used to evaluate the desirability of the BM tool for architects, suggests several criteria required for an LCA-based tool implementation in the early design. The outcome indicated that the majority of criteria, not satisfied by the BM tool, were related to the geometry parameter and associated 3D model. Thus, in order to make the decision-making process, desirable for architects in the early stage of building design, the two parameters, i.e., material and geometry, should be utilized in parallel. On the one hand, the LCA methodology in the BM tool is simplified in a way that makes the process comprehensible and easy to learn for non-LCA-experts. Since the tool is under the development, minor amendments would make the carbon footprint evaluation robust for the early stage of design. On the other hand, from the requirements of the architects' point of view, the fundamental modifications are needed in the structure of the tool. If architects intend to work with such an LCA-based tool, they have to make an extra effort to translate the resulted information from the environmental assessment tool to the inputs of the modelling tool and vice versa. This leads to an undesirable and inefficient design process for architects.
53

Supporting Sustainable selection for lubricants in automotive industry : Constant velocity joint grease as a case study

Murugesan, Rajan, Raafat Youssef Afifi Elsisi, Mohamed January 2023 (has links)
Sustainability within automotive industry has been an important topic that is covered in several studies. Due to the multi-aspect nature of sustainability and the variety of the factors need to be taken in consideration when choosing a material, the decision-making process could be challenging. This study focuses on lubricants within the automotive industry and proposes a framework consisted of three milestones that aspire to assist automotive manufacturers in sustainable lubricant selection. The study uses LCA as an environmental assessment tool for fully formulated lubricants and multicriteria decision matrix to include other criteria indicators in the decision-making process quantitively. The study also contributes to the literature by performing LCA for fully formulated lubricants. The framework was applied on well-established case company within the automotive industry (Volvo Cars Corporation) in Sweden. The results showthe importance and significant impacts of the inclusion of the additives in LCA studies done on lubricants using CV joint grease as a case study. It also shows the effect of the organisational preferences on the final results of the framework.
54

Techno-economic and environmental analysis of alternative pathways for urea fertilizer production.

Rodriguez, Wilson January 2023 (has links)
The increasing global population has placed significant pressure on meeting food demands, leading to the widespread use of fertilizers to enhance crop yields. Urea, being the most used fertilizer globally, has contributed to improved agricultural productivity. However, conventional urea production technologies heavily rely on fossil fuels, resulting in substantial greenhouse gas emissions and contributing to climate change.  As the demand for urea fertilizer is projected to rise in the future, there is a growing societal concern for environmental sustainability. Consequently, alternative technologies are being developed to produce urea with claims of reduced environmental impacts compared to conventional production technologies.  The objective of this master's thesis was to identify available production technologies for the materials involved in urea production, analyse different technological pathways and compare their environmental impacts and cost implications. The analysis considered several scenarios involving variations in the sources of electricity, methane gas and water used during the production process.  The analysis focused on Global Warming Potential (GWP), Primary Energy use (PE) and associated costs. The environmental analysis was conducted through a cradle-to-gate perspective based on a life-cycle impact assessment (LCIA). The cost analysis was based on a material flow cost accounting (MFCA).  The results for the green, hybrid and progressive technological pathways were benchmarked against the traditional pathway for urea production. The findings indicate that all these alternative pathways can reduce the GWP or PE values, which could be linked to the utilization of electricity sources with low GWP, such European and Swedish electricity mix, and the generation of by-products in the pathways However, within the context of the research assumptions, it was not possible to achieve a simultaneous reduction that included cost reductions alongside GWP and PE.  The study highlights the challenges of outperforming the efficiency levels of traditional technologies with other technological alternatives. Furthermore, it emphasizes the importance of carefully considering the integrations of the technologies and better utilization of residues and by-products exploring an integration of systems under an industrial symbiosis approach.  Finally, it is important to consider the trade-offs between environmental performance and cost when defining technological pathways for urea production.
55

Analysis of the impact of anthropogenic pollution on shallow groundwater in peri-urban Kampala

Kulabako, Robinah January 2005 (has links)
An investigation to assess the anthropogenic pollutant loads, transport and impact on shallow groundwater in one of Kampala’s peri-urban areas (Bwaise III Parish) was undertaken. Bwaise III is a densely populated informal settlement with a high water table (&lt;1.5 m) and inadequate basic social services infrastructure (e.g, sanitation, safe water supply, roads, etc). Field surveys were undertaken to identify, locate and quantify various pollutant sources. Information on the usability and operational aspects of the excreta and solid waste management systems was obtained from consultations with the residents. Water from installed monitoring wells and one operational protected spring and wastewater (sullage) characteristics (quality, discharges for drains and spring, water levels for the wells) as well as soil characteristics (soil stratigraphy, physical and chemical) were determined through field and laboratory measurements. Laboratory batch experiments were undertaken to estimate phosphorus sorption potential of the soils. The results reveal that excreta disposal systems, solid waste and sullage are the major contributors to shallow groundwater contamination. High contaminant loads from these sources accumulate within the area resulting in widespread contamination. The water table responds rapidly to short rains (48hr) due to the pervious and shallow (&lt;1 m) vadose zone, which consists of mostly organic fill material. Rapid water quality deterioration (increased thermotolerant coliforms, organic content in the form of total kjedahl nitrogen, phosphorus) following rains potentially follows from leaching, desorption and macropore flow. Spatial variation of the water quality in the area is largely related to anthropogenic activities within the vicinity of the well sources. Animal rearing, solid waste dumps and latrines are seen to result in increased localised microbial and organic content during the rains. The spring discharge with high nitrate levels does not respond to short rains suggesting that this source is fed by regional baseflow. The corresponding high microbial contamination in this case is a result of observed poor maintenance of the protection structure leading to direct ingress of contaminated surface runoff. Natural attenuation of contaminants is very limited. Estimated bacteria die-off rates are very low, about 0.01hr-1, suggesting a high risk for microbial contamination. The soils still have potential to retain additional phosphorus, whose sorption is largely a function of iron, available phosphorus and moisture content of the soils. This is also seen with the model results in which the phosphorus contaminant plume sticks to the surface irrespective of the rainfall infiltration rates. Simulation results show that continuous heavy intense rains (&gt; 0.25mm/min) result in rapid flooding occurring within 1hr to 2 days. With lower rains, the water table does not rise to the surface, and no flooding takes place. Protection of the shallow groundwater in the area requires socio-technical measures targeting reduction of pollutant loads within the area as well as a wider spring catchment. Re-protection of the spring, coupled with awareness creation, should be immediately addressed so as to reduce microbial contamination. Community participation in solidwaste management should be encouraged. Resource recovery systems such as composting of the mostly organic waste and use of ecological sanitation toilet systems should be piloted in the area. Successful operation of the systems however depends on continuous sensitisation of the communities. / QC 20101207
56

Circular resource management in a land clearance scenario: Sollihøgda Plussby case

Segura Montoya, Isabel January 2018 (has links)
The construction of cities involves the use of land for new spaces and infrastructure. Construction on undeveloped land poses a dilemma on how to deal with the natural resources found on the construction site. Circular economy could provide guidelines on how to harness these resources, so they become products that circulate through as many cycles as possible, therefore decreasing resource consumption and waste. This research aims to explore alternatives to harness the natural materials extracted during the land clearance process of a new urban district: Sollihøgda plussby. Additionally, a new method to examine the circularity of the suggested products will be tested: the longevity indicator. The method of this thesis consists of three parts: (1) an inventory to define which natural materials are found in the construction site and their main characteristics, (2) interviews with industry experts to gain a technical insight on the possible uses for the materials, and (3) a longevity indicator to measure the circularity of the proposed uses. This research found that the forest in Avtjerna consists of Norway spruce, Scots pine and birch. The sediments are mostly humus with a turf sheet cover, while most of Avtjerna’s bedrock is categorized as rhomb porphyry lava. Norway spruce and rhomb porphyry lava have the required quality to become high-quality products for the construction industry, and they could be used directly in the project. High-quality products have longer lifetimes and more possibilities of recycling and reuse, therefore they scored higher when calculating the longevity indicator, which means a higher material retention. The other materials (Scots pine, birch, other sediments and rocks) have also possibilities of becoming products that could be used in Sollihøgda Plussby, but the longevity indicator for these materials was lower than those of Norway spruce and rhomb porphyry. Despite the usefulness of the longevity indicator to provide a preliminary assessment, this method needs to be upgraded so it incorporates other CE parameters. There should be a distinction on how many times the material is recycled, the lifetime of the recycled products, and the quality of the products obtained from the recycling process. Inventorying the natural resources on a construction site is a practice that should become common, since it allows to determine how materials can be harnessed, but also which areas should be preserved due to their ecological value. Additionally, the longevity indicator should not be used in isolation, but the environmental impacts of each suggested product should be assessed too.
57

Influence of logging residues on MeHg accumulation in soil / Påverkan av avverkningsrester på ackumulering av MeHg i mark

Blomgren, Axel January 2018 (has links)
Forestry has been found to increase the accumulation of methyl mercury (MeHg), a highly neurotoxic compound, in forest soils. However, little is known about how forestry influences catchment processes that governs the mercury (Hg) methylation process. Logging residues are used in harvested catchments in stick roads to reduce soil disturbances caused by forestry machinery. Logging residues left on site after harvest have been suggested to act as a source of high-quality organic matter that stimulates the activity of the microorganisms that carry out the methylation of Hg. In addition, logging residues might influence the activity and abundance of methylating bacteria by reducing the temperature fluctuations in soils below residues and by increasing the soil moisture content. To evaluate the impact of logging residues on the accumulation of MeHg, an experimental field study was carried out in three sites, one in Uppland and two in Västerbotten. The concentration of MeHg was compared between soils covered with residues and soils without residues, and between the lower and upper parts residue piles. Logging residues were not found to influence the levels of MeHg in soils. However, an increased accumulation of MeHg was found in the lower part of residue piles. The accumulation of MeHg in the lower parts was accompanied by a reduced temperature amplitude and an increased water content compared to the upper part of the piles. The increased formation of MeHg might have been mediated by an increased water content in the lower part of the residue piles, possibly by increasing the abundance and activity of Hgmethylating microorganisms due to suboxic/anoxic conditions within biofilms around decomposing needles. The dissolved organic matter composition in soil water differed in soils below residues compared to without residues, but the organic matter signature in soil water under residues was not found to be compliant with an elevated mercury methylation rate. As MeHg accumulated in the lower part of residue piles could become mobilized and transferred to surface water, the suitability of using logging residues in stick roads depends on the location within the catchment. The removal of logging residues could prevent the potential mobilization of MeHg from residue piles. Though, as soil disturbances may cause an increased Hg methylation rate and mediate MeHg export to surface waters, other form of protection, e.g. logging mats, should be used if logging residues are not used to protect soils. / Mänsklig aktivitet har lett till förhöjda halter av kvicksilver (Hg) i atmosfären. Genom långväga transport och deposition har detta orsakat förhöjda halter i svensk natur. Den huvudsakliga exponeringsvägen av Hg för människan sker genom konsumtion av fisk. Halterna av Hg i svensk insjöfisk överstiger EU:s gränsvärden för god kemisk status samt Världshälsoorganisationens riktlinjer för konsumtion i majoriteten av svenska vatten. Ackumuleringen av Hg i biota sker främst i form av metylkvicksilver (MeHg) som är starkt neurotoxiskt. Avverkning av skog tros bidra till en ökad bildning av MeHg i skogsmark genom att skapa miljöer som gynnar etableringen och aktiviteten av de mikroorganismer som omvandlar icke-organiskt kvicksilver (Hg(II)) till organiskt kvicksilver (MeHg). Dessutom kan skogsbruk bidra till en ökad export av MeHg till följd av ändrade hydrologiska förhållanden samt markskador. En ökad bildning av MeHg är oönskad då mobilisering sedermera kan ske till vattendrag där MeHg kan ackumuleras i akvatisk biota. Dock är kunskapen om hur skogsbruk påverkar specifika processer som är av betydelse för metyleringen av Hg begränsad. Inom skogsbruk används avverkningsrester, bestående av till exempel grenar och toppar, i rishögar för att skydda marken mot körskador. Avverkningsrester som lämnas kvar på området efter avverkning tros bidra till en ökad metylering genom att utgöra en källa av högkvalitativt organiskt material vilket kan stimulera bakteriell aktivitet. Dessutom kan avverkningsrester bidra till en ökad metylering av Hg genom att minska temperaturfluktuationerna i mark täckt med ris samt öka markens vattenhalt, vilket kan bidra till en ökad etablering samt att stimulera aktiviteten av Hg-metylerande mikroorganismer. För att utvärdera effekten av avverkningsrester på ackumuleringen av MeHg genomfördes en experimentell fältstudie där koncentrationen av MeHg jämfördes i mark täckt med ris och mark utan ris. Dessutom undersöktes huruvida en ökad metylering kan ske i den nedre delen av riset, vilket skulle kunna möjliggöras av bakterier i biofilmer kring ris under nedbrytning. Koncentrationen MeHg var högre i den nedre delen av rishögarna jämfört med den övre delen. I den nedre delen av riset var temperaturfluktuationerna lägre och vattenhalten högre än i den övre delen av riset. Ackumuleringen av MeHg kan ha skett via biofilmer i de nedre delarna av riset, där tillgången till hög kvalitativt organiskt material samt mer syrefria förhållanden kan ha gynnat etableringen och aktiviteten av de bakterier som utför metyleringen av Hg. Däremot hade typen av marktäcke, dvs mark täckt med ris och mark utan ris, inte någon påverkan på metyleringen av Hg. Karaktären av organiskt material i markvatten skiljde sig mellan typ av marktäcke, men visar inte på att avverkningsrester utgör en källa av högkvalitativt organiskt material. Vattenhalten i mark under rishögar skiljde sig inte jämfört med mark utan ris, men temperaturen var lägre med mindre variation i mark under rishögar. Därmed visar resultatet på att avverkningsrester kan bidra till en ökad bildning av MeHg. En potentiell mobilisering av MeHg som bildats i rishögarna skulle därför kunna bidra till en ökad export av MeHg från avverkade områden. Användningen av avverkningsrester, för att skydda marken vid körning med skogsmaskiner, anses ändå vara fördelaktig för att minimera utläckage av MeHg. Körskador kan skapa stående vattensamlingar där MeHg kan bildas samt kompaktera mark och skapa snabba ytliga flödesvägar i området. Däremot tyder resultatet på att användningen bör ske med hänsyn till att förhindra eventuell transport av MeHg till vattendrag. Ifall avverkningsrester inte används för att motverka markskador bör ett substitut användas, exempelvis stock-mattor, då körskador kan bidra till en ökad metylering och mobilisering av MeHg. Dock saknas kunskap om eventuell mobilisering av MeHg från rishögar till vattendrag och detta bör utvärderas i framtida studier.
58

Ekosystemtjänster : - med exempel från Flens kommun / Ecosystem services : - with examples from Flen

Ekström, Amanda January 2018 (has links)
Ekosystemen bidrar med många olika tjänster som är en förutsättning för att människans och samhällets behov ska kunna tillgodoses. Av den anledningen är det av största vikt att hänsyn tas till ekosystemtjänsterna och att de planernas för i stads- och samhällsplaneringen. Bland Sveriges miljömål finns ett par etappmål som handlar specifikt om ekosystemtjänster. Där framgår att vikten av ekosystemtjänsterna samt vad de påverkas av ska identifieras. Ekosystemtjänster kan delas in i fyra olika kategorier: Reglerande-, försörjande-, kulturella-, och stödjande ekosystemtjänster. De stödjande tjänsterna är en förutsättning för övriga tjänster och kan vara till exempel jordmånsbildning och geokemiska kretslopp. De kulturella tjänsterna är tjänster som bidrar till människans välbefinnande och hälsa, såsom friluftsliv och estetiska värden. De reglerande tjänsterna fås från naturens reglering vilket kan vara reglering av vattenflöden eller klimat. De försörjande tjänsterna är produkter som fås av naturen såsom livsmedel och vatten. Ekosystemtjänsterna påverkas av klimatförändringarna som innebär varmare och torrare klimat med risk för mer extrem nederbörd, exempelvis våtmarker riskerar att torka ut. Samtidigt är ekosystemtjänster viktiga då de motverkar effekter av klimatförändringarna. Bland annat minskar risken för översvämningar på grund av naturens förmåga att reglera vattenflöden och även hindra vatten från att nå markytan.   Syftet med rapporten är att identifiera ekosystemtjänster i Flen samt beskriva dess koppling till klimatförändringar. Resultatet kommer att fokusera på reglerande och kulturella ekosystemtjänster vilka har en stor betydelse i den bebyggda miljön. Resultatet fås och presenteras genom en litteraturstudie och inspiration från Metrias, Naturvårdsverkets, Huddinge kommuns och Högskolan i Gävles arbete med identifiering av ekosystemtjänster genom att studera ett områdes marktäcke. En karta tas fram över marktäcket i Flen och ekosystemtjänsterna presenteras sedan i en tabell, kopplande till marktäcke. Flens kommun består av mycket skog och sjöar. Där finns även åkermark och våtmark. Dessa marktäcken bidrar med många viktiga ekosystemtjänster från samtliga kategorier. / Ecosystems provide many different services that are essential for meeting human and social needs. For this reason, it is very important that ecosystem services are taken into account and are an important part of the urban planning. Among Sweden's environmental goals, there are two goals to achieve, that deal specifically with ecosystem services. The goals describe that the importance of ecosystem services and what they are affected by should be identified. Ecosystem services can be divided into four categories: regulating services, provisioning services, cultural services, and supporting ecosystem services. Supporting services are essential for the three other services. Two different supporting services is for example soil formation and geochemical cycles. The cultural services are services that contribute to well-being and health, such as outdoor activities and aesthetic values. The regulating services are obtained from nature’s natural regulations, which can be for example the regulation of water flows or the climate. The supply services are products obtained from nature such as food and water. Ecosystem services are affected by climate change, which means warmer and drier climate with the risk of more extreme precipitation, for example wetlands risk to become dry. At the same time, ecosystem services are important as they prevent the effects of climate change. For example, the risk of flooding is reduced due to the nature's ability to control water flows and also prevent water from reaching the ground surface.   The purpose of the report is to identify ecosystem services in Flen and describe its connection to climate change. The result will focus on regulating and cultural ecosystem services which are of great importance in the built environment. The result is obtained and presented through a literature study and inspiration from Metria, the Swedish Environmental Protection Agency, the town of Huddinge and the University of Gävle's work on identifying ecosystem services by studying an area's ground cover. A map is drawn over the covered area in Flen, and ecosystem services are then presented in a table linking to the ground cover. Flen consists of a lot of forests and lakes. There are also farmland and wetlands. These ground covers contribute many important ecosystem services from all four categories.
59

Optimala biodrivmedel för inblandning i diesel : En jämförelse mellan tre biodrivmedel / Optimal biofuels for mixing in to diesel : A comparison between three biofuels

Blomqvist, Camilla, Zingmark, Natalie January 2019 (has links)
2018 beslutade Sveriges regering att införa en reduktionsplikt som ämnar att reducera växthusgasutsläpp inom transportsektorn och därmed öka användningen av biodrivmedel. Bränsleleverantörer i Sverige har genom reduktionsplikten en skyldighet att blanda in förnyelsebart drivmedel i fossila bränslen. För diesel ska motsvarande 20 procent växthusgaser reduceras med hjälp av inblandning av biobränsle fram till 2020 och från 2021 och framåt ska 21 procent växthusgasemissioner reduceras varje år. Målet om en fossilfri fordonsflotta 2030 förväntas därför uppnås successivt år för år genom detta initiativ. Problematiken är dock att det idag inte finns tillräckliga mängder av biodiesel för att kunna ersätta fossilt diesel till den nivå som plikten ställer krav på. Det krävs därför forskning, innovationer och investeringar för att kunna möjliggöra en expandering av biodieselproduktionen så att behovet av biodrivmedel kan mötas. Syftet med denna rapport är att undersöka vilket biodiesel som är mest optimalt för inblandning i diesel utifrån tillgång, kostnad och miljöpåverkan. Målet är en fossilfri och miljömässigt hållbar transportsektor och för att undersöka vilket biodiesel som presterar bäst har en litteraturstudie genomförts på drivmedlen HVO (hydrerad vegetabilisk olja), FAME (fettsyrametylester) i form av RME (rapsmetylester) och FT-diesel (Fischer Tropsch-diesel) i form av BTL (biogas i flytande form). Sedan har en multikriterieanalys (MKA) följt av en känslighetsanalys implementerats för att jämföra de tre alternativen mot varandra på ett flertal, av författarna utvalda, kriterier. Resultatet visade att HVO genererade högst medelvärde vilket antas vara det mest optimala. I känslighetsanalysen som genomfördes för att testa resultatets osäkerheter och sensitivitet mot hypotetiska förändringar, presterade HVO och FT-diesel bäst. RME presterade sämst i multikriterieanalysen och känslighetsanalysen, vilket innebär att den inte lämpar sig för att användas i större grad än det görs idag. Den kritik som riktar sig mot verktyget MKA innefattar oftast att resultatet innehar en viss typ av subjektivitet sådant att poängen som tilldelas påverkas av författarnas kunskaper och erfarenheter. En av anledningarna till att känslighetsanalys genomförs är för att försöka eliminera denna osäkerhet. De parametrar som har störst inverkan på resultatet och som författarna anser ha mest påverkan på den framtida utvecklingen är tillgången på råvaror, produktionskostnaden samt hur mycket som produceras av varje drivmedel årligen. Slutsatsen är att HVO är mest optimalt för inblandning i diesel idag, men står inför utmaningen att finna alternativa råvaror då restprodukter som HVO produceras av finns i begränsad mängd. BTL skulle vara en stark kandidat om det gjordes investeringar så att det skulle bli tillgängligt på den kommersiella marknaden. RME har många brister och lämpar sig inte för expandering, ett beslut som EU redan tagit och som denna rapport styrker. / In 2018, the Swedish government decided to impose an obligation of reduction that aims to reduce greenhouse gas emissions in the transportation sector and thereby increase the use of biofuels in our society. Fuel suppliers in Sweden have through this obligation of reduction a responsibility to mix renewable fuels into fossil fuels. For diesel an equivalent of 20 percent of greenhouse gases must be reduced by mixing in biofuel until 2020 and from 2021 onwards, 21 percent greenhouse gases will be reduced each year. The goal of a fossil-free transportation sector in year 2030 is therefore expected to be achieved successively year by year through this initiative. The problem, however, is that there are not an enough amount of biodiesel today to be able to replace fossil diesel to the level required by the obligation. Therefore research, innovations and investments are required to enable the expansion of the biodiesel production so that the need for biofuels can be met. The purpose of this report is to investigate which biodiesel is the most optimal for mixing in to diesel based on supply, cost and environmental impact. The goal is a fossil-free and environmentally sustainable transport sector and to perform this investigation of which biodiesel performs the best, a literature study has been conductedon the fuels HVO (hydrogenated vegetable oil), FAME (fatty acid methyl ester) in the form of RME(rapeseed methyl ester) and FT-diesel (Fischer Tropsch diesel) in the form of BTL (biogas to liquid).Then, a multi-criteria analysis (MCA) followed by a sensitivity analysis has been implemented to compare the three alternatives against each other in a number of criteria selected by the authors of this report. The result showed that the fuel HVO generated the highest average value from the MCA, which is as sumed to be the most optimal. In the sensitivity analysis conducted to test the results uncertainties and sensitivity to hypothetical changes in the future, HVO and FT diesel performed best. RME performed poor in the multi-criterion analysis and the sensitivity analysis, which means that it is not suitable for use to a greater extent than it is today. The criticism that is directed at the tool MCA usually involves the result having a certain type of subjectivity such that the points awarded are influenced by the authors' knowledge and experiences. One of the reasons why sensitivity analysis is carried out is to try to eliminate this uncertainty that the subjectivity brings. The parameters that have the greatest impact on the result and which the authors consider to have the greatest impact on the future development are the availability of raw materials, the production cost and how much is produced by each fuel annually. The conclusion is that HVO is most optimal for mixing in in dieseltoday, but is faced with the challenge of finding alternative raw materials since decay products that HVO are produced from occur in a limited amount. BTL would be a strong candidate to being the most optimal for blending in if investments were made so that it would be available on the commercial market. RME has many short comings and is not suitable for expansion, a decision that the EU has already taken and which this report validate.
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Energieffektiviseringar för energi- och miljöcertifiering av Smaland Airport AB

Gustafsson Ivemon, Kim, Lundgren, Robert January 2011 (has links)
Målet är att identifiera och ge fullständiga åtgärdsförslag på energieffektiviseringar för att minskaenergianvändningen med 25 % och därmed uppnå kraven för Green Building. De fullständigaåtgärdsförslagen ska redovisa ekonomi-, miljö- och hälsoaspekter.För att uppnå syftet med examensarbetet har ett konsekvent tillvägagångssätt använts för attidentifiera potentiella energieffektiviseringar för Smaland Airport. Med hjälp av den bakomliggandestudien ”Energieffektiviseringar Smaland Airport 2010-2011” analyserades kartläggningen avflygplatsens system och processer.Den totala energibesparingen för Smaland Airport uppgår till 646,1 MWh eller 22,04 % vilket fallerinom ramen för Sveriges klimatmål med en sänkt energianvändning på 20 % fram till och med 2020från 2008 års nivå. För att uppnå denna besparing krävs investeringar på 2,78 Mkr. Den årligareduceringen av koldioxid som fås av föreslagna energieffektiviseringar uppgår till 49,53 ton. Dengenomsnittliga pay-off tiden för investeringarna är 7,6 år vilket visar på attenergieffektiviseringsarbetet på Smaland Airport anses vara ekonomiskt försvarbart sett från ettlångsiktigt perspektiv.Energibesparingen som Green Building baseras på uppgår till 556MWh eller 23,15 % vilket inte ärtillräckligt för att klara huvudmålet på 25 % som krävs för att få fastigheten Green Buildingcertifierad. För att lyckas med huvudmålet krävs det att fler energieffektiviseringar identifieras och genomförs. / The goal is to identify and provide complete proposals for actions on energy efficiency to reduceenergy usage by 25 % and thus achieve the requirements for Green Building. The proposals shallaccount for economic, environmental as well as health aspects.To meet the objective of the thesis a consistent approach was used to identify potential energyefficiency of Smaland Airport. With help of the underlying study "Energy Efficiencies of SmalandAirport, 2010-2011" the airport's systems and processes were surveyed and analyzed.The total energy savings of Smaland Airport amounting to 646.1 MWh or 22.04% which falls withinthe framework of Sweden's climate goals with a lower consumption of 20% until 2020 from 2008levels. The requested investment to achieve these savings amounts to 2.78 million crowns. Theannual reduction of carbon dioxide obtained by the proposed energy efficienciesamounts to 49.53 tonnes. The average pay-off period for proposed investments is 7.6 years whichindicates that the energy efficiency work at Smaland Airport is considered to be economicallyjustified, as seen from a long term perspective.Energy savings from green building based on the amount to 556MWh or 23.15% is not enough tomeet the primary objective of 25% which is required to obtain property Green Building certified. Toachieve the main goal requires more energy efficiency measures identified and implemented.

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