Swedish biogas is currently produced mainly by anaerobic digestion of sewage sludgeat sewage treatment plants, landfills and anaerobic digestion of household or industrialwaste. Also cattle ma-nure from farms can be used to produce biogas. Upgradingbiogas represents an increase in methane concentration from about 65 % to about 97%. In addition, particles and contaminants must be sepa-rated from the upgradedbiogas. There are various methods for upgrading and this report compares sixdifferent methods with respect to environment and economy: water scrubber,Biosling, cryo technology, chemical absorption, Pressure Swing Adsorption (PSA) andmembrane separation.According to the used ORWARE model, chemical adsorption with amine has the leastenvironmen-tal impact (methane emissions) and the lowest costs.

The austenitic stainless steel 316L has been compared to duplex stainless steels to be able to highlight a choice of material for manufacturing of spare tanks used for cooling water at nuclear power stations on the Swedish west coast. In this report 316L and the duplex stainless steels 2205, 2304 and LDX 2404 have been compared according to corrosion resistance, strength, manufacturing aspects and prices. The steels arranged by increasing corrosion resistance: 316L < 2304 < LDX 2404 < 2205. The steels arranged by increasing strength (considering the thickness of the plates needed for construction): 316L < 2304 < LDX 2404 and 2205. The steels arranged by increasing price/tank: 2304 < LDX 2404 < 2205 < 316L.

Since energy simulations are used to verify that projected residential buildings will reach the current energy requirements it is important that the results are reliable.This report investigates the extent of uncertainty in energy simulations, estimates the causes of the uncertainty and its economic and environmental consequences.The method used in this report is based on three validation methods; empirical validation, analytical validation and comparative validation. The analysis was carried out for five multi-family dwellings in Uppsala with installed meters for energy measurements. One of these objects, Klockarlunden, was studied in more detail than the others.The results show that the deviations are between 10 and 29% for the studied objects, which means that the uncertainty is estimated to be at least 29%. All simulations underestimate the buildings need of energy. The simulation for Klockarlunden can predict the energy consumption to be within the range of 46-98 kWh/m2year with 90% confidence level based on the current uncertainty.

Arbetet handlar om en mätare som heter Water Content Monitor WCM411. Det är en fukthaltsmätare som används i det här arbetet för att mäta den verkliga fukthalten i råbentonit. Den är tillverkad i Finland med ganska ny teknik. Den bygger på infraröd mätteknik och är helt beröringsfri.Syftet med det här arbetet är kunna mäta fukthalten i råbentoniten på ett tillförlitligt sätt i det nya verket som ska byggas i Sandskär. Fukthalten ska kunna styra temperaturen och mängden på torkluften till bentoniten.Utrustningen behöver kalibreras innan den tas i bruk.

Nordic Marine Sauna AB has, since 2005, designed, manufactured and sold floating saunas. Theproduct are characterised by a well thought thru and appealing design and its high quality. Thecompany is now intending to open a new business area by starting a subsidiary, NordicSubmarine Sauna AB, which will design submerged saunas. The expected customers are leisureand conference centres as well as customers that seek an experience out of the ordinary.Due to the products technical complexity a master thesis was adverted. The task was to do aninvestigation whether such a product is technically viable.The job involved research of existing products and constructions material as well as designingthe product with CAD and FEM-programs.

Abstract The aim of this study was to explore and describe the pupils' thoughts on seed and its development into seedling. Twenty nine Swedish pupils at the age of 7 and 10 years old were interviewed about their knowledge of seeds.It turned out that pupils often have so-called everyday belief to describe the natural science phenomenon by connecting their explanations to phenomena in everyday life to which they are familiar. To describe the process of seed developing into seedling is something that most of the pupils believe to be difficult and this resulted mostly in the answer ?it is growing.? Children have some knowledge about what seeds need in order to germinate but they do not mention the importance of oxygen as a component of seed to be able to germinate and grow. They mean instead that it is sufficient with soil, water and sun.The older pupils, however, are more often than the younger pupils able to connect their reflections to a more scientifically correct description based on terms belonging to the phenomena, though these terms sometimes are wrongly used.

AbstraktÅberg, E. & Öhrn, L. (2008) Krögares förhållningssätt till berusningsdrickande. C-uppsats i pedagogik. Institution för pedagogik, didaktik och psykologi.

By immersion in the situation of the food production today and a historical study of how past development has led us to this point, one goal of this essay is to discuss whether the current way of farming can be applied in a sustainable future. Another objective of the essay is to study the vision Vertical farming as an alternative approach, and to focus on different aspects of this phenomenon in order to provide as comprehensive a picture as possible.The paper, thus, seeks to broaden the views for alternative approaches regarding a well-established method which we often take for granted. The aim is also to initiate a discussion around the need to also take radical ideas in regard if we want to face the future in a sustainable manner. The method is a qualitative literary study where scientific articles and papers have been used to discuss the issues: why has the idea of Vertical farming arisen, what is Vertical farming and how is the Vertical Farm meant to operate? Does Vertical farming have a place in the sustainable city of the future? For a long time us humans lived as one with nature, in a symbiotic relationship in which we gave and took as a functioning part of an ecosystem.

The purpose of this thesis is to describe and analyse the road towards a modern library in the southern archipelago of Gothenburg between the years 1943 and 1976. The archipelago consists of about thirty smaller and larger islands, of which seven are inhabited throughout the year. Styrsö and the surrounding islands composed a municipality of their own until 1973. In January 1974 it became a part of the municipality of Gothenburg, this is also the year when the only bridge in the archipelago was ready to be taken into use, between Donsö and Styrsö. There is no bridge between the mainland and the islands.

This report is made as a literature review, focusing on the work done to increase understanding of efficiency in the categories of substations and secondary heating systems, with respect to the deviation from the theoretically possible cooling off in the distribution network as well as the economic benefit that appear. The main purpose of a considerable part of the literature used in this report addresses the issue of identifying individual causes of reduced cooling in district heating systems. These literature resources have been compiled and summarized as part of the report.The technology of district heating is associated with benefits such as better use of the energy in a fuel. This is the case of cogeneration plants where serial generation of electricity and thermal energy increases efficiency compared with the parallel generation where heat is generated locally and electricity is generated centrally. Serial generation thus allows for lower primary energy demand.

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.

Preservation of cells and tissues by freezing at temperatures below 70°C has led to new possibilities for the storage of germ cells for fertility preservation. During the freezing process problems might occur, the greatest being ice crystallization which can cause membrane destruction and thus cell death. To minimize this risk, solutions that reduce the freezing point can be added to reduce crystallization and increase survival rates. These solutions are called cryoprotectants. The best method for freezing is still not known.The aim of this study was to analyze the effect of various parameters on the survival rate of human semen frozen with liquid nitrogen.

In the year 1783 a fissure eruption from Laki in the southern part of Iceland produced a large amount of volcanic gases during a period of eight months. The volcanic gases and aerosols spread across the northern hem sphere due to ideal weather conditions and had a substantial impact on the environment, human health and also climate effects. This, so called dry fog, caused severe health problems, which led to death casualties, killing animals, crops and other vegetation. The consequence was a widespread famine which was aggravated by a hard and long winter in 1783/84. Analysis shows that the Icelandic volcanoes are the primary risk to produce dry fog that can affect Sweden.

The hotel is located on Skatholmen in the archipelago of Stockholm, Värmdö county. The hotel building has an open structure characterized by hospitality and the nature outside. The rooms have stunning views of the island landscape and lush forest. With biodiversity and valuable nature in mind, the building has been designed with a structure that should not be too intrusive in the surrounding landscape. The building is meant to blend into the dark silhouette of the island and to give a light footprint on the topography of the landscape.The use of well-chosen materials and similar design, both in plan and facade, creates a consistent building despite the building's somewhat playful expression.

One of today problem at IVT industries would be assembly of insulation on water cisterns. The element of assembly insulation on the cistern gets too elevated; hence one has to climb onto the stand the cistern is assembly on. This will increase the risk of work related injuries when there is a risk of falling down. It?s also rather strenuous on shoulders due to work with your arms high above your head.