Ashes have properties that can be exploited in various applications, e.g. some ashes can be used in the construction of barriers in a landfill final top cover. A landfill top cover is a multilayer construction that protects the environment in several ways, for instance hindering gas emissions from the landfill body and water infiltration into the waste.Impervious natural materials like clay, synthetic materials like geomembranes or bentonite carpets, geosynthetic clay liners or combinations of such materials are commonly used in landfill top cover constructions. Since differential settlement may occur and the lifetimes of the synthetic materials are uncertain, it is advantageous to use thick mineral constructions. There is a great need for these materials, and substantial savings of resources can be made if alternative waste materials, like ashes, are used. Currently, ashes are either landfilled or used as construction materials. They are subject to weathering processes, including physical, chemical and mineralogical changes caused (inter alia) by fluctuations of temperature and humidity, atmospheric gases or acid rain. Ashes contain various potentially hazardous and non-hazardous chemical compounds. Therefore, precautions must be taken to avoid leaching of substances such as heavy metals into the surrounding environment. Mineral phases that are initially present and/or that form during the ageing are primarily responsible for the immobilization or leaching of diverse metals and salts. Newly formed mineral phases like clay minerals are of main interest, because of their very high cation exchange capacity, swelling and expansion properties.The conditions found in a landfill environment are likely to favour clay mineral formation. This thesis is based on studies on the effects of accelerated ageing on refuse-derived-fuel (RDF) fly ashes, in experiments under controlled laboratory conditions, intended to derive models to predict the stability of RDF fly ashes used in a landfill liner and the mineralogical changes that occur in them. A reduced factorial design was applied, followed by multivariate data analysis, to evaluate the effects of five factors - carbon dioxide (CO2) levels, temperature, relative air humidity (RH), time and the quality of added water - on mineral transformations within the ashes, and their acid neutralization capacity (ANC) and leaching behaviour.Minerals (ettringite and hydrocalumite) promoting the immobilization of hazardous compounds were found in both fresh ash and ash aged under atmospheric conditions, but these minerals disappeared upon carbonation. The main phases in ash at 20% and 100% CO2 were calcite, gypsum/anhydrite and vaterite. The abundance of gypsum and anhydrite was directly related to the temperature at which ashes were aged. The major mineral phases detected in ashes aged under 20% CO2, 65% RH and 30°C (corresponding to conditions generally found in a landfill cover) were calcite and gypsum/bassanite. The pH values of these ash specimens ranged from 7.2 to 7.6, indicating advanced carbonation. Ageing decreased pH values from 12.4 to 7.2, consequently affecting the leaching behaviour of most chemicals measured in the leachates. Levels of Ba, Ca, Cl, Cr, Cu, Pb, K and Na decreased over the study period while those of Mg, Zn and SO4 increased. No clay minerals were detected by XRD and SEM analysis in either fresh or aged ashes. However, geochemical modelling indicated that such minerals may precipitate. The modelling also indicated that clay minerals like saponite, vermiculite, chrysotile and hydrotalcite were likely to precipitate in most leachates from ash aged for 3, 10 and 22 months. Smectite, montmorillonite and illite may precipitate in leachates of ash aged for 31 months. The formation of smectite, montmorillonite and vermiculite would be advantageous due to their very high cation exchange capacities, which would favour the stabilization/immobilization of heavy metals in the mineral phases. / Askor har egenskaper som kan användas, en del askor kan t ex användas vid konstruktion av tätskikt i en deponisluttäckning. En deponisluttäckning är en flerskiktskonstruktion som skyddar miljön från t.ex. växthusgaser från deponin och hindrar vatteninträngning till avfall. Naturliga täta material som lera, syntetiska som geomembraner eller bentonitmattor eller en kombination av dessa är vanligt förekommande i sluttäckningskonstruktioner på deponier. Eftersom differentialsättningar kan uppkomma och de syntetiska materialens livslängd är osäker, är det en fördel om tjocka mineraliska konstruktioner kan användas. För dessa är materialbehovet stort och det är en stor resursbesparing om alternativa material, som aska, kan användas.Aska utsätts för åldringsprocesser både när den deponeras eller användas som byggmaterial. Materialet genomgår fysiska, kemiska och mineralogiska förändringar orsakade av t.ex. variationer av temperatur och luftfuktighet, atmosfäriska gaser eller surt regn. Aska innehåller olika farliga och ofarliga kemiska föreningar. Därför måste försiktighetsåtgärder vidtas för att undvika läckage av tungmetaller i miljön. Befintliga och nybildade mineralfaser är främst ansvariga för immobilisering eller utlakning av olika metaller och salter. Nybildade mineralfaser som lermineraler är av stort intresse på grund av deras mycket höga katjonutbyteskapacitet, svällnings- och expansionsegenskaper. Förhållandena som råder i en deponisluttäckning förväntas gynna lermineralbildning.Denna avhandling är resultatet av studier av effekten av accelererad åldring på flygaska från energiutvinning. För att förutsäga stabiliteten i flygaska som används i ett deponitätskikt har laboratorieexperiment utförts för att studera effekterna av accelererad åldring under kontrollerade förhållanden. Ett reducerat faktorförsök har gjorts för att utvärdera påverkan av fem faktorer: koldioxid (CO2), temperatur, relativ luftfuktighet (RH), tid och kvalitet på tillsatt vatten. Inflytandet av dessa faktorer på mineralomvandlingen i askan, askans syraneutraliserande förmåga (ANC) och urlakningsbeteendet har analyserats och utvärderats med hjälp av bl a multivariat dataanalys. Mineraler (ettringit och hydrocalumit) som främjar fixeringen av farliga ämnen finns i både färsk aska och prover som åldrats under atmosfäriska förhållanden men försvann efter karbonatisering. Aska som åldrats under 20 % och 100 % CO2 hade kalcit, gips / anhydrit och vaterit som huvudmineraler. Förekomsten av gips och anhydrit var direkt relaterad till temperaturnivån som askan hade åldrats i. Aska som åldrades under 20 % CO2, 65 % RH, 30 °C temperatur (motsvarande förhållandena i en deponitäckning) hade kalcit och gips/bassanit som huvudmineraler. pH-värdena i proverna varierade från 7,2 till 7,6 vilket indikerar en långt fortskriden karbonatisering. Åldrandet sänkte pH-värdena från 12,4 till 7,2 och påverkar därmed urlakningsbeteendet för många lakvattenkomponenter. Barium, Ca, Cl, Cr, Cu, Pb, K och Na minskade under tiden, medan Mg, Zn och SO4 ökade jämfört med den färska askan. Inga lermineraler upptäcktes med hjälp av XRD och SEM i varken färsk eller åldrad aska. Geokemisk modellering visade dock möjligheten för dessa mineraler att bildas och fällas ut. Lermineraler som saponit, vermikulit, krysotil och hydrotalcit kunde enligt beräkningarna bildas i lakvatten från de flesta proverna som åldrades i 3, 10 och 22 månader. Smectit, montmorillonit och illit kan bildas i lakvatten från 31 månaders åldrad aska. Bildning av smectit, montmorillonit och vermikulit skulle var värdefull på grund av deras mycket höga katjonutbyteskapacitet, vilket gynnar stabilisering / immobilisering av tungmetaller i askan.

Substrate pre-treatment has been gaining interest in anaerobic digestion (AD) as a means to increase biogas yields with nowadays more diversified substrate sources. The objective of this thesis is to identify improvement potentials and development needs within applications of substrate pretreatment in anaerobic digestion (AD) based on literature and specific examples, with special focus on the impact assessment and exemplified by the case of electroporation(EP) pre-treatment.The substrate inherent limitations to conversion of organic material to methane include content of non-biodegradable organic compounds, incorporation of biodegradable matter into recalcitrant structures and large particle size. WAS and lignocellulosic material are specific substrates that express significant substrate inherent limitations, especially WAS from WWTPs with long sludge age and lignocellulosic material with high lignin content.Improved AD performance relies on increasing operational methane yield as to approximate as much as possible the actual potential methane yield of the substrate at the highest possible digestion rate. This could potentially be achieved by the application of a pre-treatment, via the mechanisms of particle size reduction/solubilisation of biodegradable/bioavailable matter and/or conversion/exposure of non-biodegradable/non-bioavailable matter as to make it available or degradable. Pre-treatment mechanisms that could potentially counteract these effects are the removal of organic matter and/or the formation of refractory compounds. Pre-treatment by electroporation has the potential to affect substrates and, in some cases improve AD process performance. However, the effect of a specific pre-treatment may differ depending on the type of substrate upon which it is applied. The assessment of pre-treatment effects may be performed on different levels, representing impacts from micro to macro scale. On a substrate level, COD solubilisation is commonly measured, but the interpretation is aggravated by the application of different measurement approaches. In addition, solubilisation of COD as a result of pre-treatment does not necessarily translate into increased operational methane yield, and vice versa, the increased operational yield is not necessarily caused by increased COD solubilisation. On an AD process performance level, BMP tests have been used to assess both increased biodegradability and increased rate of degradation. Both applications rely on appropriate set-up as well as understanding of the limitations of the test. Substrate pre-treatment affects the quality of the outputs as well as the downstream processes of an AD process. A systematic approach is therefore necessary to understand how the introduction of a pre-treatment process as well as the changes in process performance with respect to qualities and quantities of outputs affect the balances of the system with respect to assessment bases such as energy, CO2 or economics.Several areas that would gain from further development can be identified within the area of substrate pre-treatment. These include improved understanding of substrate characteristics with improved descriptors, such as improved understanding of COD composition, and of BMP applicability and limitations. In addition, improved understanding of the relationship between substrate composition and process performance would be helpful to improve the understanding of different pre-treatment effects.Improved understanding of system effects where case-specific conditions can be considered is necessary for the full-scale implementation of pre-treatments to a larger extent. The application of tools for systems analysis to systems including pre-treatment should be further evaluated and a sensitivity analysis with respect to which specific conditions may render pre-treatments beneficial or non-beneficial should be performed.The practical applicability of electroporation pre-treatment for different substrates needs further development and the energy efficiency of the pre-treatment should be evaluated considering upscaling effects.

Bottom ash has similar properties as crushed rocks and gravel, andcould replace some of the 40 million tonnesof virgin material used for road constructions each year.However, results presented in the literature indicate thatthe leaching of e.g. Cr, Cu, Mo, Pb and Zn can cause athreat to the sur rounding environment if the materialis used as it is. A common pre-treatment method is carbonation, whichwill reduce the pH and thereby decrease the leaching of several metals. This treatment is however not always enough, so alternative methods areneeded. One possibility could be to increase the number of sorption sites for the metals. The importance of iron oxides as sorption sits for metals isknown from both mineralogical studies of bottom ash as well as from theremediation of contaminated soil, where iron is used as an amendment.Zero valent iron (Fe 0) was therefore added prior to accelerated agingin order to increase the number of adsorption sites for metals and thereby improving the leaching quality. The performed leaching tests showed that theaddition of Fe 0 prior to accelerated aging improved the quality of the leachate compared with untreated bottom ash. There was also a significant de crease of Cu, Cr, Mo and Zn from bottom ash treated with Fe0 prior to accelerated aging com pared with bottom ash submitted to only accelerated aging. In order to make an environmental assessment of the bottom ash pretreated with Fe 0 prior to accelerated aginggeochemical modeling was performed using different pH and redox potentialsin order to simulate variations in the environment.The results in dicated that the leaching of Cr, Cr, Mo and Pb would not cause harm to the environment.Zn, however, was affected by changes in pH and leached in harmful aounts at pH values velow 6 and above 10.There are reasons to question the results from the geochemical modellingsince the results from pH-stat tests showedthat several elements leached at potentially harmful levelsat several of the tested pH. To fully evaluate the effect of addition of Fe0should the mineralogy of the pretreated bottom ash be evaluated further, in order to see what forms iron oxides are pre sent and if other metals are associated with them. However, in order to improve the quality of bottom ash,focus should be directed torwards what type of wastes that areincinerated and on the incineration process.

Increasing emissions of greenhouse gases and subsequent impacts on environment and societypronounces the need for transition into renewable energy globally. Sweden aims to achieve 100 %renewable electricity by year 2040 with a major share expected to come from wind power. In this context, the national strategy developed for wind power development estimated expected shares from each County and directed the County Administrative Boards (CAB) to work in close collaboration with themunicipalities to achieve these goals. On the other hand, unsustainable wind farm siting may lead toecological and societal impacts such as noise and visual impacts, collision risk for birds and bats, etc. With these increased expectations on wind power from each county without compromising the sustainabilitytraits, the motivation to integrate Spatial Multi-Criteria Analysis (SMCA) as a planning support tool ishigh. There are however some concerns in applying SMCA planning support tools in real-world planningcontexts. This thesis aims to support regional and municipal wind power planning by developing the REWIND methodological framework based on SMCA, with integration of GIS-based tools as well as a novel conflict score to better handle goal conflicts (Paper 1). In addition, this thesis also addresses areas of the SMCA methods that need more attention to be useful in a planning context (Paper 2). In particular, a relatively simple but still systematic weighting method is developed, which enables transparentintegration of stakeholder input to get weights that match their perception of importance and comprehend the implication of it in the form of a planning tree (Paper 2). The methodology of the thesis includes literature review, and SMCA case studies with application of the REWIND methodological framework in Västernorrland and Västra Götaland Counties, including stakeholder involvement through focus group discussions. This thesis shows that there are several challenges associated with integration of SMCA in real-world planning contexts. For example, challenges that emerged from the focus group discussions lie inidentification of criteria and spatial indicators for different scales of planning, standardisation of spatial indicators, invisible trade-off during aggregation and weighting of these indicators, and control of weighting. For sustainable wind power planning, a systematic and transparent approach and a collaboration platform that enables planners to choose from the decision space with more clearunderstanding about the trade-off in a quantified manner can improve the acceptance of the REWIND framework into planning contexts. / Ökande utsläpp av växthusgaser med medföljande påverkan på miljö och samhällen belyser behovet aven övergång till förnybar energi globalt och i Sverige. Sverige har som mål att till år 2040 uppnå 100 % förnybar el och en större andel förväntas komma från vindkraft. I den nationella strategin som tagits framför vindkraftsutvecklingen föreslogs länsstyrelserna att i nära samarbete med kommunerna ta fram förväntade andelar vindkraft för att uppnå dessa mål. Samtidigt kan en ohållbar lokalisering av vindkraftsparker leda till ekologiska och samhälleliga effekter såsom buller och visuell påverkan, kollisionsrisk för fåglar och fladdermöss, habitatförlust och –fragmentering, etc. Med dessa ökadeförväntningar på vindkraft från varje län är motivationen hög att integrera metoder som rumslig flermålsanalys (Spatial Multi-Criteria Analysis, SMCA) som ett planeringsstöd för att integrera de olika hållbarhetsmålen. Det finns dock vissa farhågor när man använder SMCA-verktyg i verkliga planeringssammanhang. Detta arbete syftar till att stödja den regionala och kommunala vindkraftsplaneringen genom att utveckla det metodologiska ramverket REWIND baserad på SMCA, med integrering av GIS-baserade REWIND-verktyg samt en ny metod för konflikt kartering för att bättre hantera målkonflikter (Artikel 1). Dessutom tar denna avhandling också upp områden inom dagens SMCA-metoder som behöver uppmärksammas mer för att vara användbara i planeringssammanhang (Artikel 2). Den relativt enkla men ändå systematiska viktningsmetoden Ranking-Rating (RR) utvecklades, som möjliggör en transparent integrering av intressenternas inspel för att få vikter som matchar deras uppfattning om faktorernas betydelse och ökar förståelsen av innebörden av viktningen genom ett planeringsträd (Artikel 2). Avhandlingens metodik inkluderade litteraturgranskning, fallstudier med utveckling och tillämpning av REWIND-ramverket i Västernorrlands och Västra Götalands län, inklusive rumslig analys och involvering av intressenter genom fokusgruppsdiskussioner. Denna avhandling visar att det finns flera utmaningar förknippade med integrering av SMCA i verkliga planeringssammanhang. Till exempel ligger utmaningar som framkom i fokus gruppsdiskussionerna iidentifiering av kriterier och rumsliga indikatorer i olika planeringsskalor, standardisering av rumsligaindikatorer, risk för osynlig avvägning under aggregering och viktning av dessa indikatorer samt kontrollav viktningen. För hållbar vindkraftsplanering kan ett systematiskt och transparent tillvägagångssätt och en samverkansplattform, som gör det möjligt för planerare att välja från beslutsutrymmet med en tydligare förståelse för avvägningen på ett kvantifierat sätt förbättra acceptansen av REWIND-ramverket i planeringssammanhang / <p>QC 230116</p>

Sverige har god tillgång till vattenresurser tack vare det nordiska klimatet och den geologiska sammansättningen. Dock förväntas den pågående klimatförändring påverka Sveriges vattenresurser. Särskilt utsatta är kustnära områden som Värmdö vars geologi består till stor del av hårt kristallint berg och har begränsad tillgång till stora grundvattentäkter. Värmdö är dessutom ett av Sveriges snabbast växande kommuner och befolkningen förväntas öka med 58 procent fram till år 2050. Sammantaget kommer situationen kulminera till ett ökat tryck på kommunens vattenförsörjning, särskilt på sommaren när boende i kommunen nästan fördubblas. En vanlig metod för att stärka grundvattentillgången är konstgjord infiltration som innebär att vatten från en ytvattenkälla pumpas till en särskild infiltrationsbassäng och infiltreras ner till grundvattentäkten. Ingarö har en grundvattentäkt som Värmdö kommun avser förstärka med konstgjord infiltration med sjön Återvallsträsket som ytvattenkälla för att möta kommande utmaningar med vattenförsörjning till följd av klimatförändring och befolkningstillväxt. Denna uppsats syftar att uppskatta den framtida nettotillrinningen från avrinningsområdet för Återvallsträsket och bedöma huruvida det erforderliga uttaget från sjön är hållbart ur ett långsiktigt perspektiv med avseende på sjöns återhämtningsförmåga, befolkningstillväxt och ett tidigare domstolsbeslut som reglerar vattenståndet. Uppsatsens metodik utgörs av en litteraturstudie och tillämpad modellering. Återvallsträskets avrinningsområde har fastställts genom mjukvaruprogrammet ArcGIS med kartor och geo data från Lantmäteriet och SGU. Observerad meteorologiska data är hämtad från SMHI:s mätstationer på Värmdö och klimatscenariot har bearbetats av SMHI:s klimatforskningsenhet Rossby Centre. Tillrinningen har beräknats fram med hydrologiska beräkningsmetoder. En jämförelse sker genom tre ögonblicksbilder, en nutida med värden från år 2019 och två framtida prognostiserade modellberäkningar från år 2060 och 2099. Resultatet visar på en trend med ökad nederbörd under vår och sommar samt en nedgång under vinter och höst medan avdunstning ökar för samtliga årstider. Avrinningsområdet till Återvallsträsket har en area på 5,2 km2 och tillsammans med den månatliga nettotillrinningen antyds en god möjlighet till påfyllning från december till mars men under april till september finns en risk för otillräcklig återhämtning. Slutsatsen antyder att Återvallsträskets förmåga att användas som ytvattenkälla för konstgjord infiltration inte är entydig men med noggrann planering kan eventuella risker förebyggas och grundvattenmagasinet kan utökas. / Ingarö has a groundwater resource that Värmdö Municipality intends to reinforce with artificial infiltration with the lake Återvallsträsket as a surface water source to meet future challenges with water supply as a result of climate change and population growth. This paper aims to investigate feasibility from a hydrological perspective in a future climate scenario. The thesis methodology consists of a literature study and applied modeling and the runoff has been calculated using hydrological calculation methods. A comparison is made of three snapshots, one for present times and two future forecast model calculations. The result shows a trend with increased precipitation during spring and summer and a decrease during winter and autumn while evaporation increases for all seasons. The catchment area to Återvallsträsket has an area of 5.2 km2 and, together with the monthly net inflow, suggests a good opportunity for replenishment December to March, but in April to September there is a risk of inadequate recovery. The conclusion suggests that the ability of Återvallsträsket to be used as a surface water source for artificial infiltration is not clear but with careful planning contingent risks can be prevented and the groundwater reservoir can be increased.

Restaurering av övergödda sjöar och hav är en betydande del av de miljöåtgärder som görs i Sverige och runt om i världen. Restaureringen är viktigt för att bibehålla en stor biologisk mångfald och en god vattenkvalitet i sjöar och hav. Ökade fosforhalter från gödsling bidrar till övergödning av sjöar och effektivare metoder för att reducera fosforhalter i vatten behöver utvecklas för att nå uppsatta nationella och internationella mål. Syftet med studien var att studera tidigare behandlingar av den eutrofa sjön Hönsan i Hedemora samt att göra ett experiment med ett filter, Polonite, för att undersöka om det är en effektiv metod för fosforreduktion. Hönsan har de senare åren lidit av dåligt siktdjup, fiskdöd samt algblomningar och tidigare behandlingsmetoder har haft positiva resultat i ytvattnet men bottenvattnet (hypolimnion) har fortfarande stora problem. Metoden bestod av ett kolonnförsök i laboratorium med avsikten att simulera hur fosfornivåerna i Hönsan skulle förändras med en sådan filtreringsprocess. Kolonnförsöket innebar att vatten och sediment, hämtat från hypolimnion i Hönsan, placerades i två akvarium. Akvarium 1, vars vatten pumpades genom Polonitefiltret och Akvarium 2, vars vatten pumpades genom kolonner med glaskulor i syfte att ge referensvärden. Resultatet visade att sjövattnet som passerat polonitefiltret reducerade fosforinnehållet med 95,1% medan referensvattnet endast hade en minskning med 7,1%. Utöver fosfornivåerna i akvariumen ändrades även pH i vattnet. Polonitefiltreringen medförde en höjning av, det initialt neutrala, pH-värdet till 12,03 när materialet var som mest reaktivt medan referensfiltreringen inte förändrade pH nämnvärt. Polonite visade sig vara ett effektivt sätt att rena fosfor i eutroft sjövatten men eftersom pH- nivån höjs så pass mycket efter filtrering bör det filtrerade vattnet inte återföras till hypolimnion utan till ytvattnet där det kan neutraliseras genom blandning med resterande vatten i sjön. En kombination av behandlingarna kornhalmskasetter, gröna öar samt polonitefiltrering kan därför anses vara en bra metod för restaurering av Hönsan. Förmågan hos Polonite att binda fosfor gör materialet även lämpligt som gödselmedel när dess bindningsförmåga har avstannat och filtret är mättat med fosfor. / Restoration of lakes that suffer from eutrophication is a big part of the environmental work in Sweden and other countries around the world. Eutrophication in waters leads to decreasing biodiversity and bad water quality and the restoration work is important in order to reach global, national and regional environmental goals. Increasing levels of phosphorus is the main reason why the eutrophication process reaches a damaging level in lakes and finding a method for removal of phosphorus is key to be able to restore the lakes. The goal of this study was to analyze previous treatment methods that has been used in the lake Hönsan in Hedemora and to try a filter material for removal of phosphorus; Polonite. Hönsan has suffered from algae bloom and death of fish as a result of eutrophication. Treatments done on the surface of the lake has had positive results for the surface water, but the bottom layer of water is still damaged by high levels of phosphorus. To try the filter material, water and sediment was brought from Hönsan to KTH and used in an experiment in which Polonite’s phosphorus reduction capacity was tested. The results of the experiment showed that Polonite reduced 95,1% of the phosphorus in the water and that the filtration also resulted in a rise in pH-level. The conclusion of the experiment and this report is that Polonite is efficient as a material for phosphorus reduction through filtration. After filtration with Polonite the water should be returned to the surface water in the lake so as to be neutralized before reaching the bottom layer of water. A preferred treatment method for Hönsan is to combine filtration with Polonite with other treatments placed on the surface of the lake that has already been used in Hönsan.

The primary purpose of this thesis is to account for a new method of limiting the risk of smoke leaking out from the open fireplace into the room. The improved functionality is obtained by adding a turnplate to the open fireplace mounted horizontally inside the lower edge at the hood of the open fire. The streams of smoke and air, which are cold of the contact with the cool surfaces in the stove, have a tendency to fall down along the inside of the hood and continue out into the room. The stream is stopped and redirected back up into the chimney by the turnplate. The development of the method is based on measuring of temperatures and air flows in a monitored fireplace. Tests have been carried out partially in a test fireplace in full scale and partially in a model of the test fireplace at the scale 1:2. The model fireplace is made in glass which makes it possible to study and photograph the streams of smoke inside of the fireplace and oil fog has been used for the demonstration. Temperatures on surfaces and gases in the fireplace have been measured during different periods of time. These measurements have shown that the greatest risk for backwards floating air currents occurs directly after having lit the fire and during some hour after that. It is during this time the temperatures in the fireplace will rise. Measurements and also film-recordings have therefore been concentrated to these periods of time. The heat gain from the fire has been measured in connection to the tests. The distribution of the heat through radiation and convection based on the temperature measurements is shown. / QC 20101119

Demand for residential houses in urban areas has become a major problem facing town planners today. With the high increase in urbanization due to the increase in population, residential houses are becoming more difficult to find. Planners aim at developing new ideas to combat the high increase in the demand for residential buildings. In recent times, different methods of analysis have been introduced that will help planners select best locations to erect residential houses. A Geographic information system (GIS) is one of the tools for analyzing and storing a great deal of information. Over the years, GIS technology has been introduced into planning and the result has been of great help to urban planners in planning sustainable environment for residents. This research aims at using GIS technology and multi-criteria decision analysis (MCDA) to determine possible locations to build residential houses and analyzing different methods of selecting suitability areas within the study area. An MCDA map was produced from the combination of different factors and constraint which include elevation, orientation of the building (direction), the soil type and land use type. Proximity analysis was also done to find out how infrastructures (existing roads, shopping malls and health care enter) are close to the study area. Results show that the southern, eastern, and a part of western side of the study area is better to build residential houses than other areas. Three different methods (visual interpretation method, seeding method and neighborhood method) where used to find out which method produces the most suitable locations within the study area. In order to calculate the suitability areas and suitability values, the sum of pixel values were calculated for each method. The visual interpretation method servers as a standard method of deciding the suitability area covers 15,375 m² and has the highest suitability values of about 500 pixels. The seeding method was used as an automatic method for selecting the suitability area; result shows that the suitability area covers 17,421 m² and has the highest suitability value of about 1200 pixels. The neighborhood method was calculated using two different statistics (mean statistics and majority statistics). The mean statistics covers an area of 12,439 m² while the majority statistics covers an area of 14,332 m². From analysis carried out, the seeding method is preferred for selecting suitability areas than the visual interpretation method and the neighborhood method but the visual interpretation method covers more suitability area than the seeding method and neighborhood method.

The cement industry accounts for 5-7% of the global emissions of carbon dioxide, where CO2 is mainly emitted during the calcination process. However, CO2 is also absorbed by all concrete products during their lifetime through the process of carbonation. Based on a carbonation calculation model, this project investigated the CO2 uptake by Benders Sverige AB products and landfills.Benders Sverige AB produces mainly paving stones and roof tiles. During the years 2011-2020, more than 56,000 tonnes of CO2 were permanently absorbed by Benders’ products in use. This uptake corresponds to 9% of calcination emissions released during cement production. Roof tiles stand for &gt;77% of the CO2 uptake, which is most likely due to their high surface to volume ratio, which facilitates carbonation. Furthermore, roof tiles are surrounded by air whereas paving stones are mostly carbonated from their topside.It was also investigated how surface treatments affect the carbonation of roof tiles. A phenolphthalein test showed that surface treatments generally reduce carbonation, but since roof tiles are also carbonated from their underside it is possible that even surface treated roof tiles will be fully carbonated during their service life.To calculate the CO2 uptake of a concrete landfill, a hypothetical scenario was set up. The calculations show that there is a big potential in the optimisation of landfills to increase carbonation and therewith decrease the CO2 net emissions of Benders Sverige AB.

The building sector is a vital part in the progress towards environmental sustainability, because of its high potential to decrease the environmental impact. However, the building industry remains one of the most critical industries for the adoption of environmental sustainability principles, because of several unique characteristics in terms of e.g. long-lived products and many stakeholders involved. Environmental assessment tools have an important role to play in implementing environmental sustainability in the building sector, as they provide a clear declaration of what are considered the key environmental considerations and also provide a way of communicating these issues. The Environmental Load Profile (ELP) is a Swedish Life Cycle Assessment (LCA) based tool for the built environment, originally developed as an instrument for evaluation of the environmental performance of Hammarby Sjöstad (HS), a new city district in Stockholm, Sweden. The ELP is facing implementation, aiming to be established as an instrument of common acceptance. Experiences and results from the ELP has revealed that it can be applied to give a comprehensive picture of the environmental performance of a city district, but also that the tool has a number of weaknesses and there is much to improve in the practical procedures for the use of the tool in environmental assessments. This research project has the overall goal of making the ELP a stakeholder-accepted methodology for LCA-based assessment for the built environment. The overall goal includes two subgoals: (i) a research goal is to find an acceptable compromise in the design of the ELP tool between a natural science and technology based scientific accuracy and a social-science based acceptance of the tool and (ii) an implementation goal is to study and report experience from the use of the tool as developed today. The thesis consists of three papers: (i) the first is a study of two Swedish LCA-based tools for the built environment, which is based on comparative assessments using the ELP and EcoEffect (EE), (ii) the second is based on a questionnaire and interview study, in which we have investigated responses on LCA-based tools for the built environment among stakeholder representatives of Sweden’s building sector, with the purpose to identify barriers and opportunities for increased use of such tools and (iii) the third is based on case studies in HS using the ELP. We have identified the dominant environmental aspects in the ELP and also investigated the accuracy of the results. The study is completed with a development of a simplified version of the ELP, which also is applied in HS. Findings show that despite applying the comparative parts of the ELP and EE on an equal basis (i.e. the object specific data), differences in results were found. The following factors give rise to the differences: (i) differences in material grouping and life expectancy for the construction materials used, (ii) diverse Life Cycle Inventory (LCI) data and (iii) different impact assessment. The required level of knowledge to compare, analyse and evaluate assessments made with the ELP and EE, is relatively high, which creates an educational barrier towards increased tool use. A number of other barriers that could mitigate a fruitful implementation of LCA-based tools in Sweden’s building sector have also been identified. We have found barriers between: (i) the current and the desired environmental work within the sector, (ii) the knowledge of and the use of LCA-based tools and (iii) the developers of the tools and the potential users. Other barriers further identified are especially connected to: (i) data (availability and credibility), (ii) costs, (iii) time, (iv) customer pressure, (v) knowledge and (vi) incentives. We have also identified the following opportunities for increased use of the tools: (i) different design of the tools for different actors and situations, (ii) combine LCA with LCC, (iii) involve environmental assessment in the implementation of the EU Directive on energy performance of buildings, (iv) develop reference values, (v) simplify input-data collection, (vi) improve environmental labelling and (vii) provide incentives. In the development of a simplified ELP we have noticed that the most important aspects contributing to the environmental load at a city district level (50 % of the total amount), covers 91-99 % of the total environmental load. The thesis shows that different simplifications of the ELP-tool are required for different purposes, actors and situations. A simplified version of the ELP, “ELP-light” was developed and applied in HS. In the development of ELP-light, we have used some of the identified opportunities and bridged some of the identified barriers. / QC 20101105