No description available.

When evaluating and comparing household waste collection systems, various aspects are relevant to consider, e.g. environmental objectives, technical function, operating cost, types of recycling materials collected separately, property-close collection or drop-off system, economic incentives, information strategies, residential structure, social codes, etc. Data describing the actual waste flow is the basic input to evaluating the function of source-sorting programs. The questions raised are: How can household waste quantities and composition be measured? How can waste flow data from different collection systems be interpreted and compared? What factors influence the output of source-sorting programs? The usefulness and weaknesses of solid waste composition studies are discussed. Multivariate data analysis is applied in order to obtain an overview of collection and composition data, and identify influential variables, clusters and trends. In a case study, curbside collection of recyclables and weight-based billing respectively led to increased source-sorting activities. Other influential factors are listed and discussed. Eight indicators are proposed for facilitating comparisons of collection systems in an easily comprehensible way. / <p>Godkänd; 2005; 20061214 (haneit)</p>

Syfte med studien är att undersöka om nudging är en effektiv metod för att förändra beteende hos studenter på Högskolan i Gävle. Studien kommer att undersöka om två nudgingmetoder (informationskampanj och nudge) kan förändra studenternas beteende, samtidigt jämföra vilken metod som ger bättre effekt till att förändra beteende och minska köttkonsumtion. Först undersöks genom en litteraturstudie om kött påverkar klimat och hur mycket växthusgasutsläpp från kött potentiellt kan reduceras hos studenter på högskolan i Gävle med hjälp av informationskampanjer och nudge. För att vidare besvara syfte har två enkätstudier och två nudgingmetoder utförts på Högskolan i Gävle. Första enkätstudie har genomförts för att mäta hur mycket kött och vilken typ av kött som konsumeras av studenter, sedan har två nudging metoder använts i syfte till att förändra beteende och minska eller förändra val av kött hos studenter. Den andra enkätstudien har genomförts för att undersöka om kampanjerna har förändrat beteende och minskat eller förändrat val av kött hos studenter. Resultat visar att nudging har gett effekt då beteende har förändrats. Nudge har gett effekt till att reducera köttkonsumtion och koldioxidutsläpp. Enkätstudien innehöll 6 frågor där endast fråga 1 visade sig vara signifikant och kan kopplas till att nudge vid interaktion är en bidragande orsak till denna förändring. / Abstract The purpose of the study is to investigate whether nudging is an effective method for changing behavior among students at Gävle University. The study will investigate whether two nudging methods (information campaign and nudge) can change the students' behavior, while comparing which method gives better effect to changing behavior and reducing meat consumption. First, a literature study will investigate wheater meat affects the climate and how much greenhouse gas emissions from meat can potentially be reduced by students at the Högskolan i Gävle using information campaigns and nudge. To further answer the purpose, two surveys and two nudging methods have been conducted at the Högskolan i Gävle. The first survey study was conducted to measure how much meat and the type of meat consumed by students, then two nudging methods have been used in order to change behavior and reduce or change the choice of meat among students. The second survey study was conducted to investigate whether the campaigns have changed behavior and reduced or changed the choice of meat among students. Results show that nudging has had an effect and behavior has changed. Nudge has reduced meat consumption and carbon dioxide emissions. The survey study contained 6 questions where only question 1 turned out to be significant and can be linked to nudge [KH1] in the interaction, information campaign is a contributing factor to this change.

New types of materials and products are developed every day, and subsequently, new types of wastes. At the same time, new regulations are put forth to protect human health and the ecosystems from the negative impacts of wastes. Often, the waste management industry is responsible to deal with these problems, and hence, good knowledge about wastes and their treatment is crucial. Waste is normally characterized in order to determine a treatment; however, this usually implies a known treatment method. This thesis aims to provide a structured approach about how to describe different treatments, and to provide guidance on how to characterize wastes in a solution oriented manner. A distinction is made between two types of treatments: those based on separation processes and those based on transformation processes, as well as combinations of the two. Separation processes are common in mechanical treatment such as sieving or air-classification. Transformation processes are common in such treatments as shredding, electroporation, radiation treatment, and stabilization. Most treatments consist of both a transformation and a separation process, such as incineration, in which the organic carbon is oxidized (transformed) into CO2,that then is separated from the remaining solids. Other examples of combined processes are composting and anaerobic digestion. A framework is presented that enables a quantitative description of different waste treatments such as anaerobic digestion and incineration in the same context. All transformation processes take place in an environment that can be described by environmental factors such as temperature, pH, redox, radiation etc. By relating different treatments or observations to each other in an n-dimension matrix, it is possible to not only locate the currently known treatments, but also to locate unexplored areas, i.e. combinations of environmental factors that could be used to treat wastes in new ways. The addition of the n-dimensional framework to the general characterization model, together with the “top down” strategy for characterization provide valuable insights useful for dealing with new types of wastes in an efficient manner.

Incineration residues contain both inorganic and organic material. The organic material may affect the mobility of pollutants in e.g. landfills or geotechnical constructions. Limit values of TOC (total organic carbon), determined according to European standard are stipulated to reduce the disposal of organic materials. The European standard methods to determine TOC and DOC (dissolved organic carbon) are evaluated. Factors controlling the mobility of DOC and its effect on metal mobility have also been studied. Determination of TOC according to European standard methods EN 13 137 and EN 1 484 include those carbon fractions that are oxidized during combustion. The definition of TOC as total organic carbon is not equivalent with the analytical result. The European standards on the definition of TOC need revision. Both organic and elemental carbon are oxidized upon heating, and the analytical TOC is thus a sum of organic and elemental carbon present in the sample. Since elemental carbon comprise the major part of the analytical TOC in solid samples of incineration residues, such results will most likely be misunderstood. Revision of the standard method EN 13 137 is recommended to better suit incineration residues. The L/S ratio (the relationship between the mass of liquid and the mass of solid material), excessive carbonation (addition of CO2 until the pH in the solution was stable for 2.5 h) and extraction pH were the main factors controlling the mobility of DOC in incineration bottom ash. Up to ~60 weight-% of the TOC in the bottom ash could be mobilized by controlling these factors (i. e. by using them as parameters). Only a minor part of the TOC (~7 weight-%) in APC residues was extractable with water, indicating a high proportion of elemental carbon. Water-soluble organic compounds may affect the mobility of metals in several ways. The formation of DOC-metal complexes has a direct effect on the metal mobility. Biological degradation of organic material may also affect the metal mobility indirectly due to changes of pH and redox- potential. The complexation capacity of DOC can be used in the development of washing as a pre-treatment process of incineration residues. Excessive carbonation may be useful in a washing process to enhance the separation of metals. Further treatment-oriented investigations of bottom ashes and APC residues are recommended in the development of a washing process of the materials. / <p>Godkänd; 2006; 20070109 (haneit)</p>

The applicability of fly ash - sewage sludge and steel slag mixtures in landfill cover liners was investigated putting special emphasis on the hydraulic conductivity (HC) of the materials. The objective was to identify the factors significantly affecting the HC of the materials and to quantify their effects using multiple linear regression (MLR). It was discussed what impact low-HC liners might have on the landfill system and the environment. Although mainly affected by the COMPACTION ENERGY used, the HC of the fly ash - sewage sludge samples were also affected by DRYING and the factor interactions MATERIAL×ASH RATIO and ASH RATIO×COMPACTION ENERGY. The models derived using multiple linear regression could be used to predict an HC between 1.7×10-11 m s-1 and 9.5×10-10 m s-1, if a compaction energy of 2.4 J cm-3 was applied and no drying occurred. TIME between the addition of water and compaction mainly affected the HC of the steel slag samples. The HC of the steel slag mixtures was between 10-8 and 10-12 m s-1 if they were compacted immediately after water addition. The HC showed a decreasing trend during the measurement period of 53±1 days. It was suspected that cement reactions in the material influenced HC. Low-HC liners are a potential environmental hazard. Monitoring of landfill emissions is prescribed for about 30 years though contaminated landfill leachate is generated for at least one human generation. As the failing of the liner can go along with a sudden increase of leachate release from the landfill and thus with severe environmental pollution, the concept of applying low-HC liners needs to be reconsidered. / <p>Godkänd; 2006; 20070109 (mlk)</p>

No description available.

Ambitious household waste recycling programs have been introduced in Sweden and several other countries during recent decades. Many different waste- sorting and collection schemes have been developed, but the evaluation and comparison of the results is made difficult by the lack of comparable data. The aim of the research presented in this thesis was to answer the following questions: How can household waste flows be described and monitored? Which factors affect the collection results? and, What is a useful basis for the evaluation of collection systems? Waste flow analysis and waste component classification were performed in a number of Swedish municipalities, revealing a wide variation in the amount of waste per capita. Eleven site-specific variables were investigated and multivariate data analysis was performed. The study was carried out on three levels: 1) household waste as the material in itself, classified into physical components, 2) the householders and their handling of waste, in terms of average amounts of different waste categories and recyclables per capita, and 3) the municipalities, as the authority responsible for household waste management, where local conditions influence waste generation and pathways. A significant finding was that property-close collection of dry recyclables led to increased collection of sorted metal, plastic, and paper packaging. Weight-based billing, i.e. when waste collection is charged per kilogram of waste collected, showed divergent effects, which are investigated and discussed. Monitoring methods are suggested regarding the waste flow from households. A step-by-step method for evaluation and comparisons of collection systems was outlined, including a set of indicators. Sixteen sources of error in official waste statistics were identified and the results of the studies emphasize the importance of reliable waste generation and composition data to underpin waste management policies. / Ambitiösa återvinningssystem för hushållsavfall har införts i Sverige, och i många andra länder, under de senaste årtiondena. Många olika system för källsortering och insamling har utvecklats, men utvärdering och jämförelse av insamlingsresultat försvåras av bristen på jämförbara data. Följande frågor diskuteras och besvaras i avhandlingen: Hur kan avfallsflödet från hushåll mätas och undersökas? Vilka faktorer påverkar avfallsflödet från hushållen? Hur kan olika insamlingssystem göras jämförbara och utvärderas? Studien utfördes på tre nivåer:(1) hushållsavfallet, klassificerat i olika material och komponenter, (2) hushållen och deras hantering av hushållsavfallet, och (3) kommunerna, i egenskap av ansvarig myndighet för hantering av hushållsavfall, där förutsättningarna påverkas avlokala faktorer. Avfallsflödesanalyser, inklusive plockanalys av hushållsavfall, har genomförts i ett antal svenska kommuner, vilket visade stora variationer i avfallsmängder per person. Elva faktorer, som antogs påverka avfallsflödet, undersöktes och multivariat dataanalys tillämpades. Studien visar bland annat att kommuner med fastighetsnära insamling av återvinningsmaterial samlade in mer metall-, plast- och pappersförpackningar per person, jämfört med kommuner som bara hade återvinningsstationer för insamling av förpackningar. Viktbaserad avfallstaxa, dvs när hämtning av hushållsavfall faktureras per kg avfall som finns i kärlet, har visat sig ge varierande effekter i olika kommuner, vilket har undersökts och diskuterats. I genomsnitt var mängden osorterat hushållsavfall 20 % mindre per person i kommuner med viktbaserad taxa, jämfört med övriga landet. Någon skillnad i mängden källsorterade återvinningsmaterial kunde dock inte påvisas. Mätmetoder för hushållsavfallsflödet föreslås, tillsammans med en steg-för-steg utvärderingsmetod för jämförelse av olika insamlingssystem, innefattande en uppsättning nyckeltal. Sexton felkällor har identifierats i officiella avfallsdata och en slutsats av studien är att det i dagsläget saknas tillförlitliga data som beslutsunderlag för utveckling av avfallshantering och avfallspolicy. / Godkänd; 2008; 20080602 (ysko)

In this thesis, the focus is laid on the ability of natural organic matter (OM) to serve as a metal stabilising agent. The metal contaminants investigated arise from the MSWI bottom ash leachate. Besides the high content of metals, elevated pH and salinity are characteristic for ash leachate that, in turn, can alter the functionality of OM. Batch and column leaching tests were used to study the retention capacity of substrates with different amount of OM. Also, field observations were made of the influence of ash leachate on soil and plants. In this case, ash leachate was generated under field conditions from an experimental road built on municipal solid waste incineration (MSWI) bottom ashes. It has been shown that copper, chromium, and lead retention is proportional to OM content of the substrates. Zinc retention showed to have the least dependence on OM. The metals were not leached in proportion to dissolved OM. Most probably several mechanisms were responsible for the retention of metals: (i) high concentration of Ca in ash leachate could lead to the formation of Ca-dissolved organic carbon (DOC) complexes that have the ability to precipitate some metals (ionic strength effect) and prevent metal transport; (ii) high solution pH could favour hydroxide formation and counteract the metal complexation with dissolved OM, as well as (iii) surface adsorption could contribute to metal retention. Despite the good metal retention capacity of OM, a continuous metal load will occupy binding sites of OM and therefore reduce its retention capacity. Metal retention capacity of rich in OM substrate could be improved by additional soil amendments and vegetation. Tolerant plant species that are capable to grow at high soil metal concentrations and immobilize pollutants within the root zone have a potential to be used for phytostabilisation of metal contaminated soil. Such plants are also associated with a low risk of the translocation of contaminants from soil through plant roots to shoots, i.e. from one media to another. Immobilization is not a technology for the removal of contaminants from soil but for the stabilization (inactivation) of potentially toxic metals. The aim of soil remediation is to reduce the contaminant exposure and spread. Then the reduced leaching, bioavailability, as well as ecotoxicity of metals as a result of phytostabilisation might be a proper solution. Development of suitable soil and amendment mixtures capable to retain broad range of metals and interaction of plants with stabilised matrix are the questions to be answered in the future research. / Godkänd; 2003; 20070109 (mlk)

The use of industrial residues as raw materials in construction raises concerns over the potential leaching and dispersal of hazardous constituents from them into the environment. Their leaching behaviour has been studied in laboratory assays, but leaching processes in the field over larger spatial and temporal scales are more complex due to variations in the conditions the materials are exposed to, and less well understood. Hence, estimates of the potential environmental loads associated with the use of such materials based on laboratory tests may be inaccurate. This thesis addresses the environmental implications of using recycled materials in road and landfill cover constructions. The focus is primarily on the leaching of inorganic constituents from six types of materials: incineration ashes, copper smelter slag, blast-furnace slag, recycled concrete, natural rock and contaminated soil. The leaching behaviour of constituents from these materials were assessed in both laboratory batch leaching tests and monitoring programs in which the water percolating through them in field applications were sampled over one to ten years. Leaching data were evaluated using statistical and geochemical modelling. In addition, assessment methods and criteria to judge the environmental suitability of substituting natural materials for recycled materials in construction were reviewed. It was found that leachates from recycled materials in the constructions contain higher concentrations of several constituents than natural water and leachates from conventional materials. However, the rates and extent of constituent leaching were affected by the application methods in various ways that are explored and discussed. The results of simplified leaching tests did not always reflect the leaching behaviour in the field, which highlight the importance of developing assessment methods that allow case-specific factors to be taken into account. The environmental impacts of leaching must also be considered in relation to the expected impacts of the default alternative, i.e. landfilling of industrial residues and exploitation of natural resources. Combinations of case-specific assessments and system analyses would be the ideal approaches to evaluate impacts at both local and regional scales. / Användningen av industriella restprodukter som konstruktionsmaterial inom anläggningsbyggande väcker frågan om möjlig utlakning och spridning av förorenande ämnen från materialen till omgivande miljö. Materialens lakningspotential bestäms vanligen genom lakförsök utförda under kontrollerade förhållanden i laboratorium. Lakningsprocesser i fält sker dock över större rums- och tidskalor och är mer komplexa på grund av variationer i miljön som materialen exponeras för. Uppskattningar av materialens möjliga miljöpåverkan baserade på laboratorietester kan därför vara felaktiga. Den här avhandlingen handlar om den miljömässiga betydelsen av att använda återvunna material som konstruktionsmaterial i vägar och deponisluttäckningar. Fokus är i huvudsak på utlakningen av oorganiska ämnen från sex typer av material: förbränningsaskor, kopparslagg, hyttsten, återvunnen betong, naturligt berg och förorenad jord. Utlakningen från dessa material undersöktes med hjälp av både skakförsök i laboratorium och kontrollprogram där vatten som perkolerade materialen i fältapplikationer (sk. lakvatten) provtogs under ett till tio år. Lakvattendata utvärderades med hjälp av statistisk och geokemisk modellering. Dessutom granskades olika bedömningsmetoder och kriterier som kan användas för att bedöma den miljömässiga lämpligheten av att använda återvunna istället för naturliga material i anläggningskonstruktioner. Lakvatten från återvunna material i de undersökta konstruktionerna innehöll högre koncentrationer av flera ämnen än naturliga vatten och lakvatten från naturliga material. Dock var hastigheten och omfattningen av utlakningen beroende av hur materialet användes, vilket har undersökts och diskuteras i avhandlingen. Resultaten från förenklade skakförsök överensstämde inte alltid med observationerna i fält, vilket understryker vikten av att utveckla bedömningsmetoder där fallspecifika faktorer kan tas i beaktande. Miljöpåverkan orsakad av lakning måste också ses i relation till den påverkan som kan uppstå om restprodukterna istället deponeras och naturliga material exploateras. Kombinationer av fallspecifika och systemövergripande analyser skulle därför vara det ideala sättet att utvärdera både lokala och regionala effekter av en möjlig användning av återvunna material. / Godkänd; 2008; 20081003 (ysko)