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739 Uppsatser om Organic rankine cycle - Sida 43 av 50

Käppalaverkets nuvarande och framtida rötningskapacitet : en studie i labskala

Käppala wastewater treatment plant situated on the island of Lidingö northeast of Stockholm is running a project during 2004 and 2005 with the purpose to map out the capacity of anaerobic digestion in the digesters that treat primary and excess sludge. The purpose of this thesis work, which is part of that project, was to characterize the present anaerobic digestion process and to investigate its capacity to treat other organic wastes such as restaurant waste and waste from water works. To decide the potential of both methane and biogas production from different substrates batch laboratory tests were carried out. To imitate the anaerobic digestion process at Käppala continuous tests with small scale reactors were carried out. These reactors were later fed with restaurant waste.The batch laboratory tests showed that primary sludge had a potential biogas and methane production of 0,62 and 0,35 Ndm3/g VS respectively after 40 days of digestion.

LCC-analys av FTX-system : En jämförelse av centralt- och lägenhetsplacerat

This report is the result of a thesis conducted at the consulting firm Bjerking AB andis the final part of the Bachelor Programme in Construction Engineering at Universityof Uppsala. The work aims to investigate the costs and how the choice of ventilationsystem affects building projects during a long-term period. This report covers costssuch as investment, maintenance and energy but also how they affect residents andbuilders. Building regulations for energy consumption are expected to be tougher;therefore a comparison of two different heat recovery ventilation systems(HRV-system) was made. One system is based on a centrally placed unit that coversthe whole buildings ventilation through vertical shafts.

Vattenkvalitet och risker vid ändrat intag för vattenförsörjning i Västerås

Water is the most essential resource for life. In cases where drinking water is processed from surface water it is important to ensure the raw water is of good quality, and is suitable for processing through the water treatment plant.The drinking water for Västerås is sourced from Västeråsfjärden, in the western side of Lake Mälaren. The city itself is home to marinas, ports, a wastewater treatment plant, the Svartån outlet, sewage pumping stations and stormwater outlets. Because of the negative effects these activities have on surface water quality, Mälarenergi AB is interested in relocating the raw water intake point to Granfjärden, 10 km east of Västeråsfjärden. At Granfjärden the intake point would be less exposed to the activities in Västerås, and could be placed at a greater depth, resulting in better water quality.In this Master?s thesis the water quality and the pollution risks at Västeråsfjärden and Granfjärden sites are compared.

Miljöeffekter av alternativa system för behandling av hushållsavfall i Santiago, Chile : en jämförelse mellan deponering och förbränning med energiutvinning

This report was written by Lisa Bengtson and Hanna Paradis and describes the degree thesis "Environmental impacts of solid waste treatment in the Metropolitan Region, Santiago, Chile ? a comparison between current system and incineration with energy recovery". The purpose of this thesis was to investigate if incineration with energy recovery could be motivated through an environmental perspective as an alternative to landfilling of solid waste in Santiago, Chile. The study was performed with Life Cycle Analysis as a theoretical base. In Santiago, situated in the thirteenth region of Chile, Región Metropolitana, lives 6,5 million inhabitants. The major part of the solid waste produced in the region is landfilled on three different sanitary controlled landfills situated outside the city center.

Här är alla kungar! : en fallstudie på en konferensanläggning

Organisationens mål är att de gäster som kommer till hotell/konferensanläggningen skall bli behandlade som kungar. Affärsidén i organisationens lyder: "Ursäkta ers majestät! Hos oss är alla gäster kungar". För att få gästerna att känna sig som kungar krävs samarbete, intresse av arbetsplatsen, kvalitetstänk, kommunikation och förståelse mellan personalen.Studien är en fallstudie i förbättringsarbete och skall ge organisationen verktyg att använda i förbättringsarbetet. Syftet med studien är att identifiera förbättringsområden inom en organisations verksamhet som ska prioriteras. Ett förbättringsområde ska vidareutvecklas som ett projekt.

Hantering av elektronik komponenter under Last Time Buy

The purpose of this thesis project was to study how different companies are working with LastTime Buy and through that study propose improved ways of working with this for Scania CVAB. The project aimed at studying the work processes from three different perspectives:decision models, quality aspects and liability aspects between companies.To study this, qualitative interviews with one or several representatives from differentcompanies that are affected by or involved in Last Time Buy were used. Representatives wereselected partly from Original Equipment Manufacturers, suppliers, component manufacturersand companies offering third part solutions for Last Time Buy. The companies also reflecteddifferent industries. The interviews aimed to create an understanding for the methods used atthe different companies but also the ways of thinking and the knowledge behind the choice ofthese working methods.The analysis shows that the Original Equipment Manufacturers used very similar decisionmodels for Last Time Buy, but that external factors or the company strategy made them reachdifferent results.

Igensättning av långsamfilter i Östby vattenverk i Kramfors : studie av påverkande faktorer

Östby waterworks in the community of Kramfors has since 2003 had problems of fast clogging of the slow sand filters. As the clogging appears more often, they must be cleaned more frequently which has made the drinking water preparation difficult. Wintertime it has sometimes been impossible to clean the filters which has led to their closing and this has influenced the water quality negatively.The waterworks is a surface waterworks which takes its raw water from the lake Sjöbysjön. The water is flocculated and filtered in a contact filter with the flocculent EKOFLOCK 91. Thereafter it is alkalinized before it reaches the outdoors placed slow sand filters.

Möjligheter att minska kväveutlakningen genom att anpassa kvävegödslingen till variationer inom stråsädesfält

Due to excess precipitation that cause runoff, all soils in Sweden naturally leaches nitrogen.High leaching from arable land is an environmental problem when the runoff reacheswaters. In the international agreement, Baltic Sea Action Plan, the aim is to reduce therunoff of nutrients. Sweden has agreed to reduce its load of e.g. nitrogen to the Baltic Sea.One of the proposed measures is an increased use of site-specific N-fertilization, which hasbeen shown to increase nitrogen use efficiency and therefore also reduce the nitrogen runoff.Either yields are increased with the same total amount of nitrogen, or the total quantityof nitrogen is reduced with preserved yield levels, which is profitable for the farmers.The dynamics of nitrogen leaching differs between top dressing applications above orbelow the economical optimum. There is a consensus about a difference in the dynamics,but not about its magnitude.

Invandrarföretagares användning av bootstrapping : en kvalitativ studie om invandrarföretagares användning av bootstrapping beroende på företagets livscykel och företagarens egenskaper

Både entreprenörskap och invandring har ökat kraftigt i Sverige, såväl som globalt. Idag finns det över en miljon bolag i Sverige där enmansföretag (74,8%) och mikroföretag (21,7%) utgör den största delen. Detta ger en klar syn över att det svenska näringslivet domineras främst av mindre företag. Bakom många av dessa mindre företag står individer med utländsk bakgrund. Under 2010 talades det om att var sjunde företag som startas i Sverige, drivs av en individ med rötter från en annan del av världen.En av de viktigaste drivkrafterna för ett lands ekonomiska tillväxt är företag, vilket är en stor anledning till att fokus ligger på hur dessa väljer att finansiera sin verksamhet.

Energi- och kostnadseffektiva klimatskal : För lager-, industri- och kontorsbyggnader

A study to optimize insulation thickness for stock-, industrial- and office-buildings for external walls and roof in an economical perspective has been conducted on behalf of DynaMate. DynaMate?s role is to maintain all Scania?s buildings. Analysis has also included other parts of the building envelope, such as windows, exterior doors and industrial doors. In this thesis, three different types of exterior wall constructions has been investigated, these are a sandwich design consisting of sheet metal and a another one consisting of concrete, as well as a wall of concrete with a coating of plasters.

Den bäcknära zonen vid små skogliga vattendrag i Värmland : generell beskrivning, förekomst av traktorspår samt kvicksilverhalter i körpåverkat ytvatten

Forest streams and the associated riparian zones are sensitive to disturbances and changes that occur within these riparian areas. Particularly sensitive are small streams of low order, which will have large impacts down-stream. The disturbances that occur in the riparian zones are reflected quickly in the stream. Driving with forestry machines in the riparian zone will have detrimental effects to the soil and water. Driving the machines will lead to changes in the mineral soil composition, resulting in the reduction of porosity, less infiltration, compaction, and an increased bulk density.

Outbreaks of African swine fever in domestic pigs in Gulu district, Uganda

The demand for animal products has increased in the last decades, especially for poultry and pork. Pork production has increased drastically globally, and also in Uganda. Thirty-one percent of Uganda´s population lives in poverty. Pig production is believed to play a crucial role in poverty alleviation, because of the ability to convert low quality feed into high quality protein together with high reproductive potential. African swine fever (ASF) is a lethal disease of domestic pigs often characterized by haemorrhagic fever and with mortality rates up to 100%. The disease is endemic in most sub-Saharan countries and since 2007 in the Russian Federation and Caucasus area.

Echinococcus multilocularis in wild boar : aiming at an alternative surveillance method

This study was the first part of a larger project investigating a new surveillance method for Echinococcus multilocularis. In this study we examined livers from wild boar (Sus scrofa), looking for lesions caused by E. multilocularis. E. multilocularis is a small tapeworm which has an indirect life cycle.

Towards sustainable rye cultivation : soil carbon and yield modelling for crop rotations with rye

Using the Introductory Carbon Balance Model, ICBM, five different crop rotations with rye 1. Rye-Ley-Ley-Rye-Beans-Rye 2. Rye-Rye-Rapeseed-Rapeseed 3. Rye-Ley-Ley-Rye-Potatoes-Rye 4. Rye-Rye-Potatoes-Wheat 5. Rye-Rye-Potatoes-Beans-Wheat-Rye-Potatoes-Rapeseed were tested theoretically in four different cultivation scenarios ? Straw left on the field, biogas digestate added as fertilizer. Labelled ?+straw+BD?. ? Straw left on the field, only synthetic fertilizer. Labelled ?+straw-BD?. ? Straw harvested, biogas digestate added as fertilizer.

Frigörelse av fosfor från färskt, fryst och torkat växtmaterial : ett laboratorieförsök för att öka förståelsen för fosfordynamiken inom växtodlingen

Phosphorus is the single most potent contributor to eutrophication of freshwater and has also been shown to contribute to the toxic algae blooms in the Baltic sea. The dynamics and paths of losses of phosphorus from arable lands are not fully understood. It is known that phosphorus can be lost directly from plant material to water. In studies where plant material has been subjected to several freeze-thaw cycles, large amounts of phosphorus have been lost. Most studies have been conducted under field conditions, with many factors effecting the measured losses of phosphorus, such as weather and type of soil. This study was performed in a controlled environment without the presence of soil. Instead of soil, small glass beads were mixed with the plant materials in vessels, to make possible homogeneous leaching with water through the mixture of glass beads and plant materials. In this study, clover, ryegrass and dry straw were cut to pieces, approximately 2 cm long.

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