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1564 Uppsatser om Heating water - Sida 32 av 105
Textilindustrins avloppsvatten och avloppsslam ur ett miljöperspektiv : Underlag för internationella riktlinjer inom projektet Sweden Textile Water Initiative
The aim of my thesis is to obtain knowledge of textile wastewater and textile sludge from an environmental perspective, which can be used as a basis for the ?Sweden Textile Water Initiative? guidelines for a sustainable sludge management. In my study I have mainly focused on textile dyes, salts and metals and their routes during wastewater treatment.This paper is partly a literature review, which I began by identifying the pollutants discharged from each textile process. Then I studied wastewater and sludge quality, environmental aspects, possible treatment and recycling methods. I have also tried to find existing type of guidelines in order to make comparisons.
Konstruktion av testrigg för moderna ångexpandrar
This report summarize what have been done during the Master of Science Thesis that Klas Schjelderup has written for the company RANOTOR Utvecklings AB. The company is developing modern steam engines and this work should develop a machine to perform tests on a new type of piston seal that hopefully could be used in the future. The steam engines will be both volumetric and energy compact, around 1600hp/literof cylinder volume, and it will have a lot of practical applications.The new type of piston seal is hydrostatic lubricated which means that a fluid is separating two faces that normally is in contact. In this case pressurized water is used to separate the piston seal from the cylinder wall. RANOTOR have earlier formulated that at least the expander in the modern steam engine have to be oil-free, due to other components functionality in the closed water system.
Francisella tularensis subspecies holarctica : the curious case of a water- and mosquito associated bacterium in Sweden
Francisella tularensis, the causative agent of the zoonotic disease tularaemia, is highly contagious and potentially fatal for a wide range of wildlife species of the northern
hemisphere, also humans. Although recognized as a pathogen for over 100 years, much still remains to be elucidated concerning the ecology and transmission of the bacterium, hence this literature overview aims at compiling data regarding the aquatic association and the role of
mosquitoes in transmission of Francisella tularensis subspecies holartica, the sole subspecies in Sweden. While a linkage between the bacterium and natural waters stands beyond dispute, there is no consensus in the literature concerning its potential as a reservoir. However, two
prevailing theories can be distinguished; one proposes the water association being mammaldependent and thus merely the result of contamination from semi-aquatic mammals living in
close vicinity to the water source. The other, quite contrary, suggests mammal-independence and hence that water, possibly in association with protozoa, serves as an environmental reservoir for the bacterium.
Utvärdering av miljönytta för olika miljöcertifieringssystem för byggnader : En jämförande fallstudie på Swecos kontor i Stockholm, Göteborg och Malmö
This thesis examines the environmental benefits resulting from the choice of environmental certification scheme, with focus on energy. This was carried out by studying the measures that were implemented as a result of the certification of Sweco's three largest office buildings in Stockholm, Gothenburg and Malmö. The office property in Stockholm has been certified with the Swedish Environmental Building, Gothenburg with the British BREEAM and Malmö with the U.S system LEED.The results from the study indicate that an environmental certification can reduce the energy consumption by up to 59 percent and the water consumption by 20 to 66 percent. However; the interviews, literature study and simulations in MATLAB indicate that the size and scope of these environmental benefits depend on several identified factors: the type of building and its conditions, system selection, grade level, the choice of indicators, the ambition of those involved and when in time the certification process begins. The comparison between Environmental Building, LEED and BREEAM showed that Environmental Building for the office property in Stockholm gave the largest environmental benefit in terms of reduced energy consumption thanks to several large measures.
Energianvändning i restauranger i Umeå kommun
Efficient energy use in restaurantsUmeå Municipality wishes to combine energy issues with food control, and thus help restaurants to become more energy efficient. During March and April 2010, I visited seven restaurants and interviewed restaurant personnel about current state and application of kitchen appliances, using a checklist to make sure that the same questions were asked at all restaurants. The restaurants were all different sizes and offered different kinds of food. The study mostly focuses on energy efficiency by behaviour and not on location or technology. Almost every restaurant that was visited had the potential to improve in one or more areas, such as kitchen appliances, lamps and lighting fixtures, heating, cooling and ventilation.
En flödesutjämnande driftstrategi för Uppsalas fjärrvärmesystem : En ändrad styrning av framtemperaturen
This thesis examines a possible control strategy to minimize flow fluctuations in Uppsala?s district heating system. High variations in flow rate may lead to complications caused by hydraulic constraints in the district heating system. These complications, such as inadequate pressure and temperature levels, increase the risk of heat delivery failures. It is therefore important to avoid such situations both for the producer and for the customers.Typically, the forward temperature is controlled by using a rough correlation with respect to the outdoor temperature.
Utveckling av kyl- och smörjsystem för ekobilen Agilis HCCI motor
Every year, KTH participates in the Shell Eco Marathon, a competition whose goal is to design a vehicle that can go as far as possible using only the equivalent energy of one liter of petrol fuel. This year, one of KTH?s contributions to this race is the Agilis prototype; a car powered by a uniquely configured HCCI-engine developed at the university. The engine is dependent of several subsystems in order to work properly, among other, systems for cooling and lubrication.Combustion engines are in need of a cooling system that reduces the heat developed during the combustion. In general, two main types of cooling systems are employed; either air cooling, where the outside of the cylinder is exposed to a flow of the surrounding air, ore water cooling, where water flows in tubes around the engine, and the heat are transferred by the water to the surrounding air through a heat exchanger.The purpose of the lubrication system is to prevent the friction that builds up in the interference between moving parts in the engine.
Analys av artificiella marktyper vid vatten med hjälp av GIS, Värmlands län 2007
On commission of the County administrative board in Värmland County a method was developed for analysis of the occurrence of artificial land use at lakes and watercourses. With artificial land use is meant land significantly affected by man. Two bases have been used to carry out the analysis. In one of the analysis the vegetation database and in the other GSD¹-Marktäckedata (land cover data) was used (this method has been used by County administrative board in Jönköping County).The analysis comprises all watercourses within Alsterälven river basin. The digital water bodies are created by the Swedish Meteorological and Hydrological Institute on the basis of GSD-Översiktskartan (general map).
Risken för översvämningar vid de svenska kärnkraftverken : en statistisk och historisk extremvärdesanalys
This thesis investigates the overall risks of flooding over the Design Basis Flooding Level (DBFL) at the Swedish nuclear power plants (Oskarshamn, Ringhals and Forsmark), using statistical data and methods, but also considers historical events which might affect the overall risk of flooding at the specified sites.Considering the nuclear accident which happened in Fukushima in conjuction with the earthquake and tsunami which struck eastern Japan on 11 March 2011, operators and licensors of nuclear power plants all over the world conducted reviews and investigations on the overall risks posed to the plants from external events. One important such event is extreme water level.One part of the thesis includes an extreme value analysis (using Generalized Extreme Value distribution and Generalized Pareto distribution) of water level data from SMHI (Sweden's Meteorological and Hydrological Institute) measured at stations close to the Swedish nuclear power plants. The results of the statistical studies indicate that considering the return period used in the thesis (100 000 years), the water levels at the Swedish nuclear power plants are not expected to exceed DBFL.The other part of the thesis consists of a historical study of extreme weather-related events. The results of this study indicate that no historical events seem to have occured which would indicate a higher risk of flooding than the one suggested by the statistical study. .
Att Synliggöra det Osynliga : GIS som verktyg i sökandet efter bosättningsområden från bronsåldern på Gotland
In this bachelor essay an attempt is done, to recreate a probable Bronze Age landscape on Gotland, with GIS as a tool. The landscape on Gotland is situated with many different monuments dated Bronze Age, such as cairns and stone ships. In creating of the maps, two possible shorelines contemporary with the Bronze Age have been calculated and marked on the maps. Furthermore, peat lands have been drawn upon the maps, by using the information from geological maps.A landscape variable have been compared between Bronze Age places and Early Iron Age houses; the soil type. On Bronze Age places gravel is the most common, while moraine marl is the most common on places with Early Iron Age houses.From a selection that were made, all Bronze Age places where within 3 km from the water, either the recreated shoreline or peat land.
En studie av sedimenttransport, död ved och kantzoner längs två vattendrag i Kilsbergen - från skog till slätt :
Headwater streams are affected by anthropogenic impacts at multiple scales.
One aspect of human impact is sediment transport associated to the
abundance of stream structures as large woody debris and the composition
of the riparian zone from forest to agricultural landscapes.
Riparian buffer zones and stream structures like dead wood are considered
as generally important structures for protection against an increasing
amount of sediment particles in the water. Hence, in this study these
structures were quantified in thirty different stream segments on land and in
the water.
To measure the transport of sediment Whitlock-Vibert boxes were used in
three different types of landscapes; forest, transition and fields. The boxes
were left in the stream segments for three months, the taken up and dried
and weighed. The results showed that the transition-land in Frösvidalsån
had the highest sediment transport. The second highest transport of
sediment was in Blackstaån at the fields.
Beteende hos lekvandrande lax i Klarälven ? utvärdering av en fiskfälla
During the migration season in 2013 a study on spawning migrating salmon and the effect of water flow on the behavior was conducted of the salmon at the Forshaga hydropower station in the River Klarälven. The River Klarälven with its nine hydropower plants on the Swedish side, constituting migration obstacles for the migrating salmon. Fortum Generation AB has together with the County Administrative Board restored a salmon trap at the lowermost hydropower station in Forshaga, aiming at making it possible for the salmon to swim into the trap, and thereafter be transported by truck past the power plants and then continue their journey to the spawning grounds on their own. Unfortunately, it is believed that the trap does not work as well as it should. In this study, I focused on salmon position in relation to water flow and if the number of salmon that swam into the fish trap differed between salmon with previous experience of the trap (experienced) and salmon without experience (unexperienced).
CFD simulering av kallras : Undersökning av temperatur- och luftbeteende intill höga glasfasader och i vistelsezon med golvvärme som en värmekälla
Glass has sophisticated front properties and are used as facades in high buildings. During cold periods, these glass facades could cause thermal discomfort, due to cold downdraught. Cold downdraught can be countered by placing heaters under glass surfaces. Nowadays technology offers highly insulating windows, which is why there is an interest to investigate the indoor climate with only underfloor heating. The research in this area is limited, and few empirical methods are available.
Biologiska behandlingsmetoder för rening av rejektvatten från biogasproduktion
In this literature review the characteristics of two free-floating macrophytes, water hyacinth (Eichhornia crassipes) and duckweed (Lemna sp.), and two microalgae, Chlorella and Scenedesmus, have been examined regarding their suitability as efficient nutrient removers in the treatment of wastewater with high levels of nutrients and suspended solids from a biogas plant in Loudden. The needs required for the plants to be able to grow in wastewater and the amounts of biomass they can produce have also been studied. The results show that Chlorella is capable of a very high uptake of nutrients in photobioreactors with high nutrient loadings. With an ammonia uptake maximum value at 10900mg/m2/d Chlorella outshines the other organisms in this study. The test organism that performed the closest to Chlorella in terms of nitrogen uptake was water hyacinth with an uptake about 1602mg/m2/d.
Tillämpning av en markprofilmodell för hydrologiska beräkningar i avrinningsområdesskala
There is a great need to reduce nutrient leaching from arable land into lakes and oceans. By using several different types of models it has previously been possible to describe nutrient losses in a catchment area with a minimum unit of sub-catchment level. At present, it is instead desirable to model a smaller catchment with an opportunity to re-connect the results to the corresponding fields in the catchment. Such models already exist but they are not fully able to properly describe Swedish conditions and land characteristics in our region.With the approach of creating such a model, SLU has developed a project with this work as its first stage. The model is expected to be created under the working name SWE-model which stands for Soil Water Environment and is in this first stage supposed to apply the SOIL model in catchment scale. During the procedure to describe the first step in the process of developing such a model adapted to Swedish conditions and which works in the catchment scale with an area of about 10-30 km2, focus has been set on calculating the transport of water flow from different hydrological response units. Regardless of the processes occurring in the soil after the water has been added, it is assumed that all the water which flows from each simulated unit is drained.In the first step the hydrologic response units were identified based on land use and soil type in the study area. With the help of a script with functions that retrieve and transform data, certain units were chosen for simulation. The script was also created in this project. Finally, the model results were aggregated and summarized for each unique unit, for each sub-catchment, and also for the whole catchment.From the results it is possible to see similarities in the flow dynamics between modeled and measured data. The efficiency coefficient has been calculated to correspond to the mean of the measured values for the whole simulation period. With an automated calibration process the model should be able to perform better. The volume error gives an indication of overestimation from the model..