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580 Uppsatser om Heat exchanger - Sida 17 av 39

En systemlösning för en framtida fjärrvärmeutbyggnad i Täby : ur Fortum Värmes perspektiv

At the moment in central Täby there are small district heating network operated by Fortum Heat. The distribution network has an annual heat demand of about 70 GWh, which is supported by the network's two plants, Galten and Farmen. Täby as a region is rapidly growing and there are grand plans to develop the area. Estimated market potential for a future district heating expansion in Täby is very high and as early as in 2007 Täby decided to invest in a large-scale expansion. In autumn 2009 Täby did a procurement process, known as the ?Täby initiative?, to find a partner that could implement those expansion plans. To secure a cheap basic production the partner also need to build a power plant at Hagby recycling center. Despite high interest during initial state of the process, only one procurement offer were received and Täby suspended the contract in March the following year.

Sekundärnät för lågtempererad fjärrvärme

Lower energy use in buildings is a result of increasingly stringent energy requirements across Europe. When conventional district heating technology is used in areas with low energy consumption heatlosses do not fall even though the amount of energy delivered is reduced. This reduces income for thedistrict heating company. To maintain their economic viability the district heating companies? majorchallenge is to implement new solutions that minimize heat loss.

Energipålning : En grön grundläggning

Det finns en innovativ, grön grundläggningsteknik kallad energigrundläggning. Principen är att integrera redan erforderliga, strukturella element såsom pålar med en värmeväxlare i syfte att utvinna energi. Tekniken har funnits sedan tidigt 80-tal men har knappt används i Norden. Tekniken visar på stor potential då man kan uppnå synergi genom utvinning av värme under vinterhalvåret och kyla under sommarhalvåret.I detta arbete redogörs för grundläggande principer och mekanismer bakom energigrundläggning samt en omfattande litteraturstudie av vad som tidigare har studerats inom området. Det finns få exempel i litteraturen på problematiken med förändrade geotekniska egenskaper hos jorden på grund av energiutvinningen och än färre exempel på knäckningsproblematiken hos slagna, slanka stålrörspålar.

Lönsamhetsanalys av tekniker för utökad elproduktion i kraftvärme : Med hänsyn till elprisets variationer

This thesis aims to examine the viability of various techniques for increased electricity generation in CHP plants and the effect of electricity price fluctuations on the profitability.The techniques examined are fuel dryer, pellet production, methane production, combined methane- and pellet production, seasonal heating storages in caverns and pit heat storages and condensing tail. Using Excel and Matlab, the prerequisites for investment costs, revenues and expenses were calculated.What affects the price of electricity is a combination of economic and technological development, energy prices, economic structure, population changes and weather. Different scenarios for the electricity price were therefore examined. In the base case, the electricity price was given by the Nord Pool electricity price statistics of area three in 2011. Thereafter, WiMo was used to design the electricity scenarios for 2030, which was then applied to the data to obtain the viability of various scenarios. The techniques examined were found to give greater profits to the CHP plant by increasing and optimizing the production of electricity.

Myt och vetenskap om kastration av tik

This is a literature study in which I investigate if there are scientific studies that form the basis of the Swedish dog world views concerning the spaying of bitches. The positive impacts are said to be reduced problems with pseudopregnancy, reduced risk of pyometra, reduced risk of mammary and uterine tumors, an earlier cease of bone growth, a more active and happier dog and a bitch who is more tolerant of other dogs. The negative consequences are said to be urinary incontinence, increased aggressiveness, lower metabolism and the increased risk of obesity, a more lethargic individual and altered coat.There are studies indicating that spaying reduces behavioral problems associated with heat and pseudopregnancy. Assuming no ovary tissue persists after the procedure, and there is no progesterone production, the risk of pyometra decreases. Early spaying, before the first heat, reduces the risk of mammary tumors.

Statusbedömning och förbättringsförslag för startkedjemaskineri, startkedja och linspel för stränggjutningsmaskin

The main goal with the master thesis has been to do a status evaluation of the chain machinery with its start chain and wire to secure the production on a short basis due to that a reconstruction is not planned at this time. An evaluation of the condition of the start chain and the rollers in the chain depository has been done. An offer has been requested for a new start chain and the evaluation of the start chains may be a basis for the decision taking. The production has been able to go on, although it has arisen some problems which have been difficult to find the causes for. There is no gathered ?picture? of the machinery status and a mapping of each machinery has been compiled of comprehensive logs.

Lönsam energieffektivisering : Ett samarbete mellan ÅF och kund

This thesis project has focused on studying ÅF?s business concept Energy Collaboration, which is their way of selling energy efficiency services. Thereforeongoing projects have been analyzed. The purpose was to determine achieved energy efficiency, costs and profitability for the studied projects. It was concluded that the Energy Collaboration is a good way of selling energy efficiency services, since the customer takes no risk and energy savings of about 15-25 % can be achieved with simple measures.

Val av energisystem för en hållbar stadsdel : En fallstudie av Östra Sala backe

Uppsala County has ambitious environmental aims for the planned residential area inÖstra Sala backe. In this thesis different energy sources have been evaluated todetermine which system that would be most favorable given currently availableinformation about the project. Planned energy usage has been divided into tap waterheating, space heating and power. Three base case scenarios were made with districtheating, small scale bio fuel and heat pump. Solar power and solar heating were thensimulated and the production from the two could individually be deducted from theenergy need in the base cases, constituting 9 different scenarios.

Prefabricerade Passivhus

European Union has made a new decision that all new built houses by 2020 shallbe near-zero energy houses. Boverket?s definition of near-zero energy housesintends buildings with good energy performance in which a proportion of theamount of energy that must be added to the building is made of renewable energy.Passive House is a set of requirements from FEBY designed to build energyefficient buildings. This is achieved by reducing loss of heat through the buildingenvelope and to take advantage of the passive heat from solar radiation,installation and heat sources like people living in the house.This project has been made with help of Anebyhus and one of their model houseshave been examined from the report?s issues, including Anebyhus?s energyperformance, requirements for the manufacturing and assembly, how theenvelope must be improved to fulfill the requirements for the Passive House andwhat energy calculation programs are available on the market.The report aims to provide solutions for energy efficient houses that are adaptedfor production of house building.Two visits to Anebyhus has been done to study their manufacture and assemblyof building elements.

Köldbryggor och energiförluster. En studie om energiförluster genom balkonginfästningar och deras betydelse för byggnadens totala energibehov

In this report the balconies? abutments for a property in Bo01-area in Malmö has been studied. The property which is called Vitruvius contains four build-ings where two of them have corbelling balconies with intermittent abutments. With intermittent abutment means that the 50 mm thermal bridge insulation that the balconies is equipped with, is broken regularly by a 300 mm concrete heel. The reinforcement bar that holds the balcony runs through this heel.

Fruktsamhet och fruktsamhetsproblem hos chow-chow : En inledande studie över situationen i Sverige

The chow-chow breed is considered to have a low fertility and this report is an in depth study of the reproductive functions of this breed in Sweden. Only 53 % of the Chow-chow matings results in litters. Previous studies of other breeds in commercial kennels shows mating results around 85-90 %, but this has not been investigated in hobby kennels and most Chow-chows which are bred from in Sweden, are kept as family pets. Contrary to most other breeds, Chow-chows show a seasonal reproductive pattern and most litters are born in the autumn. The influence of the month of mating on pregnancy rate and litter size was found to be not significant, but can be considered a trend. Thirty-nine females with previous known fertility problems where studied. Some of them had reached puberty extremely early, at an age between 4-5 months, and many of the bitches showed great fluctuations in intervals between oestrus cycles. Some of the females showed abnormalities such as very short oestrus intervals of only 2-3 months, probably without ovulating.

Termisk hantering av litium-jon- batterier i elektriska drivsystem

The automotive market is currently undergoing a historical change where stricter emission legislations and ever increasing fuel costs have intensified the search for effective alternatives to the conventional internal combustion engine, which has resulted in a substantial trend towards electrification of powertrains. Storage of electrical energy is the fundamental component in this technology where the lithium-ion batteries are currently considered as the most appropriate solution. Lithium-ion batteries, however, as other types of batteries, can only be used efficiently and durably within a specific temperature range.This Master thesis has been carried out in collaboration with Electroengine in Sweden AB, situated in Uppsala, which has an ongoing project regarding development of a modular battery system for electric powertrains. The project is at a stage where an initial prototype has been developed which provides the foundation for this thesis. The study has addressed the battery system performance from a thermal perspective, in order to validate the ability of the system to create a thermally serviceable environment for the lithium-ion battery cells.

Pellets - en framtidsmarknad?

With higher prices for oil and increased focus on fossil fuels impact on the environment the heating sector are searching for alternative fuels. Pellets are a quite new product whose production has risen exponential in recent years. Today there are small-, medium-and large-scale users, where the large-scale consumers are the heating sector. The heating sector is mainly using oil to cover the increased demand during cold periods. The purpose of this study is to analyze the potential of pellets if it would replace thermal power plants oil and coal. The study will also analyze the economic impact a conversion would mean for a heating plant and if the pellet is a reasonable substitute. 2008 statistics from the Swedish district heating association were analyzed and a calculation was performed to determine how many tons of pellets is needed to replace coal and oil.

UTV?RDERING AV APPLICERINGSTEKNIKER MED LASCAUX 303 HV Adhesivet Lascaux 303 HV anpassningsbarhet vid strukturella ?tg?rder p? m?leri p? duk

Lining techniques such as nap bonding and mist lining were developed in the late 20th century and have gained popularity alongside with the increased use of acrylic emulsions as adhesives. The ability of the adhesive to create a nap bond to the canvases without penetrating the fibers has shown advantages regarding reversibility. In addition, the use of moisture, heat and pressure is reduced, which can be advantageous for more sensitive paintings. These lining techniques have been included in several studies where reversibility, minimal intervention and respect for the individual requirements and problems of each object have been the focus. The adaptability of the methods has been confirmed and to further explore the adaptability, this study consists of three simpler application techniques with the adhesive Lascaux 303 HV on mockups.

NEDKYLNING HOS VANLIG B?NA, PHASEOLUS VULGARIS

Beans are a global source of plant-based protein, and in some countries, they constitute a primary source of protein intake. With ongoing climate change, including rising temperatures, it is necessary to adapt beans to ensure a reliable food supply. An important mechanism that many plants have, to cope with high temperatures, is cooling through transpiration. During transpiration, stomata open and release water vapor. Water molecules use heat energy from the leaf to convert into gas, thereby cooling the leaf.

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