Biogas is a renewable energy source that is produced by anaerobic digestion of organic mate-rial. In Sweden, biogas predominately comes from sewage water sludge and landfills or from organic waste of households and industries. Small scale digestion plants at farms are espe-cially expected to contribute to increased biogas production in the future. Biogas can be ob-tained directly in it?s raw form and used as fuel in a combustion chamber.

Då det ur ett konsumentperspektiv finns ett stort intresse för att kombinera olika miljöperspektiv i en enhetlig märkning samtidigt som forskning visar att en kombination av olika märkningar genererar en ökad betalningsvilja, åsyftar denna studie att undersöka hur dessa två respektive typer av märkningssätt påverkar konsumentens preferenser av varumärket samt hur dessa preferenser skiljer sig åt. Föreliggande studie testar dessutom huruvida Simonsons (1989) teori om kompromisseffekter är applikabel för att öka konsumenters preferenser för ekologiska produkter när ett superekologiskt alternativ tillförs ett valset med ett konventionellt och ett ekologiskt alternativ. Studien bidrar därmed med information till beslutsfattare inom livsmedelsbranschen för hur ekologiska attribut påverkar konsumenters preferenser och betalningsviljan för ekologiska produkter.   408 respondenter har medverkat i en enkätundersökning där svaren har analyserats med hjälp av följande statistiska analyser: reliabilitetstest, t-test, korrelationsanalys, faktoranalys och klusteranalys. Resultaten visar att trots att de flesta konsumenter tenderar att ha såväl en positiv attityd som en ökad betalningsvilja för de ekologiska alternativen, väljer fortfarande majoriteten av konsumenterna det konventionella alternativet, varvid ingen kompromisseffekt uppstår.

Mussel meal is a potential source of protein, with a good composition of amino acids, for laying hens and broiler chickens, and may replace the use of fish meal in organic poultry production. Lead and cadmium are heavy metals which occur in the environment and can be accumulated in mussels. When poultry are exposed to heavy metals, the metals are absorbed in the small intestine and distributed in the body in the form of ions, complexes or bound to proteins. In poultry, lead accumulates in bone tissue, liver and kidneys, while cadmium accumulates in liver and kidneys. Generally very low concentrations of these heavy metals occur in muscles of broilers which have been exposed to feed contaminated with cadmium or lead.

High levels of Hg in fish in Swedish lakes have been a problem along time in Sweden. The major concern is production and accumulation of the most toxic form of mercury; methyl mercury (MeHg). Consequently, in about half of our 83 000 lakes fish contain concentrations above the recommended limit for human consumption of 0,5 mg mercury per kg fresh weight (most of it in the form of MeHg). Consumption of fish containing too high levels of MeHg may cause problems for both humans and animals. Three major sources of MeHg in surface waters are: 1) runoff from terrestrial areas, 2) deposition from the atmosphere, and 3) internal production of MeHg in lakes and streams. The aim of this study was to investigate the effect of clear-cutting on the concentration of Hg and MeHg into draining streams.

SammanfattningI ett kraftvärmeverk binds en stor del energi i de varma rökgaserna. Genom att installera rökgaskondensering kan energi från röken tillvaratas. På kraftvärmeverket Skogsbacka i Lycksele har man tittat på möjligheterna att installera rökgaskondensering. Detta arbete syftar till att ta reda på om och vid vilka förutsättningar det skulle vara lönsamt för Skogsbacka att också investera i utrustning för elproduktion vid låggradig värme, för att på så sätt använda energin från rökgaskondenseringen. Idag finns flera tillverkare som erbjuder fristående aggregat som kan utvinna el vid låga temperaturer.

The mining industry, in terms of ore excavation and metal production, is and has been important to the Swedish economy. In connection with the ore excavation process, large amounts of partly sulphidic waste are produced. When the metal sulphides are exposed to air and water they are eventually oxidised, which leads to the formation of acidic water with high concentrations of metal cations and sulphate ions, so called Acid Mine Drainage (AMD). This water may reach the nearest surroundings and cause negative environmental effects. By covering the waste with soil or water, the oxidation process can be minimised. At the Rävlidmyran mine in the county of Västerbotten open pit mining took place between 1951 and 1991.

The goal of the society to increase the proportion of renewable energy has led to an increased demand of bioenergy e.g. forest biomass. However, there are concerns that removal of biomass will lead to decreased base cation concentrations in the soils and acidification of streams. In order to find in which types of landscape removal of branches and tops could have such negative effects, this study aims to analyse the relations between pH-sensitivity and landscape variables in the Bothnia Bay water district. GIS and digital geographical data were used to analyse the landscape in subcatchments.

This essay examines the way the recurring motifs in Karin Boye's poetry might be read as expressions of queer or subversive desire. The fact that the lyrical I is not gendered in the poems opens up for a queer reading. In adherence to Sara Ahmed's notion of desire lines and sexual orientation I discuss the spatial aspects of desire, and explore the positions and movements of the lyrical I in Boye's poetic landscape as deviations from the concept of the straight and marked path, into the queer and unknown.I trace desire in Boye's poetry mainly through the themes of nature and night, and the ways in which these phenomena deviate from the normative structures laid out by the poems. Usually the motifs of night (such as fog, shadows and darkness) are associated with the fading of the senses. The night obscures the vision of the lyrical I and wraps them in heavy silence, making them experience and desire in new ways. Through motifs related to nature Boye formulates a feminine, matriarchal myth.

Fossil fuels are affecting our climate negatively and there is a limited amount of them in the world, which leads to the importance of finding alternative fuels. One alternative is biogas, which is produced though a digestion process of different organic materials in a biogasreactor. Organic substrate that comes from farms has the biggest potential to increase the production of biogas in Sweden. Primarily crops from farms, but also waste products like manure are of great importance.Today there is a calculated theoretical potential for biogasproduction of 14TWh per year, which is around ten times larger than Sweden?s production today.

Wavecraft AB develops medical equipment for heating of organic synthesises. The heating is done with microwaves, which improves the process in both speed and accuracy compared to the more traditional methods where heating elements are used. This report discusses the developement of an automatic lid mechanism for one of Wavecraft's product prototypes. The company assumes that the final product will be integrated by customers into fully automated systems, and the upgrade from a manually to an automatically controlled lid is therefore an important step in the product's developement process.The first stage och the project was an idea generation process. The ideas generated here were organized into five different concepts of which the best one was selected through the use of a concept matrix.

In couples diagnosed with unexplained infertility, the woman has normal ovulatory cycles and no organic pathology, and the man has normal semen. The period during which the implantation of an embryo can occur is defined as the window of implantation (WOI). For infertile women, disturbances in the endometrium maturation are hypothesized to impair the uterine receptivity for embryo implantaition. However, there are still no methods found to predict endometrial receptivity.Hemoglobin related-proteins hypothesized to be involved in embryo implantation have been found in the endometrium in both fertile and infertile women. The aim of this study was to determine whether there were differences in the expression of hemoglobin-related proteins, hemoglobin-?, cytoglobin, fetal hemoglobin and haptoglobin in the endometrium of fertile and infertile women.

Small pieces of plastic, termed ?micro plastic? in the oceans derive mainly from degradation of big plastics such as beach littering, but also from sources of direct emission from e.g. beauty scrubbers and synthetic sand-blasting. These micro plastics are ingested by marine animals ? mistaking them for plankton ? or via prey.

It is a well-known fact that textiles and carpets have benign sound-absorbing properties. It is desirable to have quantified values of these properties ? especially for architects and interior designers. They often need to be able to giveaccount for the acoustic properties of their designs at a relatively early stage and sometimes have strict acoustic classifications imposed upon them by their contractor. A product with documented acoustic properties would aid when prescribing interior elements.The purpose of this thesis is to develop a wall-mounted panel in hand-tufted material ? aesthetically pleasing and versatile but also having documented and quantified acoustic properties.

The main project Dry preservation of source-separated organic household wastes involves a new technique for treatment of biowaste through drying. Investigations are going on to determine how the dried biowaste best can be used to close the natural circular flow of nutrients. The objective of this degree project is to determine if the dried biowaste can be used as a soil conditioner. By restoring the nutrients in the material to the ground, the natural circular flow is closed. A declaration of contents, including the nutrient levels, C/N ratio, pH and the electrical conductivity of the dried biowaste, was constructed and a germination test was done to make sure that the material did not inhibit sprouting.

In a sustainable society the use of renewable energy and recycling of materials is of high importance. Wastewater treatment plants use large amounts of energy in the processing of wastewater. This study seeks to evaluate wastewater as an energy resource and to examine treatment plants potential to become sustainable energy producers. The study is based upon the internal processes of Himmerfja?rdsverket.