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1771 Uppsatser om Air-water heat pump - Sida 22 av 119

Det kan vara farligt att ligga lågt - om stadsplanering inför stigande vattennivåer : Exempel från Göteborg, Kristianstad och Arvika

In this study is being examined how cities can be planned in the face of rising water levels and extreme weather, due to the changing climate. The starting point has been to investigate how the problems can be tackled and how the positive sides of water in the city can be strengthened, and synergy effects and greater sustainability be achieved thereby. The method has been literature studies and case studies containing interviews and visits. Göteborg, Kristianstad and Arvika have been studied for discussions and ideas about adaptation. Today, building near water is very popular which brings both advantages and disadvantages.

Produktutveckling av koncept för isbanesystem

Today most ice rinks in Sweden use secondary refrigeration systems with a solution of calcium chloride and water as secondary refrigerant. Due to the large amount of energy such a system uses more efficient systems would be desired.An earlier study concluded in the possibilities of using carbon dioxide as secondary refrigerant with copper tubes as the loops in the ice rink. Since then 3 ice rink refrigeration systems has been built with carbon dioxide in copper tubes. Excluding the ones being direct involved in those projects there is still very little knowledge about how these system works. This study has been made primarily with the aim of adding to the knowledge concerning availability and cost and secondary to look at possibilities for improvement.A comparison between systems with carbon dioxide, calcium chloride respective ammonium solved in water has been made by using Decision Matrix.

Konstruktion och montering av ett gasspjäll för en HCCI-motor.

Denna rapport handlar om införandet av ett gasspjäll i den HCCI motor som utvecklas påKungliga Tekniska Högskolan (KTH) i Stockholm. Detta gasspjäll styr effekten ocharbetssättet i motorn. Med en gasspjäll är det möjligt att byta från gnistantändning tillHCCI-läge. Under projektet har många andra områden förbättrats, till exempel luft- ocholjepump. För att dra slutsatser är det nödvändigt att analysera några av motorns data sominsamlats under utvecklingen, såsom cylindertryck, insprutningsdata och tändläge.

Biobränsleanvändning och Flameless oxidation i degelugnar för glassmältning

Idag värms glasugnar upp med antingen gasol eller olja, detta projekt vill visa på möjligheten att istället använda gas från biobränsleförgasning som förbränns utan synliga flammor. Detta skulle miljömässigt ge fördelarna att biobränslen inte bidrar till växthuseffekten och ge förutsättningar för att minska kväveoxidutsläppen genom bättre teknik än dagens.För att visa att det är möjligt att både behålla produktionen och reducera kväveoxiderna med förgasningsgas konstruerades en modell av ugnen och strömningsbilden studerades i vattenmodell. För att undersöka värmeöverföringen i ugnen behöver en eller flera kalorimetrar konstrueras för att kunna användas vid varma försök. Dimensionsberäkningar gjordes som visade att detta är möjligt med vissa typer av kalorimetrar..

Optimerande av gasanläggning - genom värmeåtervinning och förlustreducering. Gässlösa Reningsverk

The municipality, of Gatukontoret in Local government of Borås has in the long run, a required need to look after the current heating devices (the gas production plant) in sewage treatment plant, called Gässlösa. The practical work of the examination is about, trying to find a better way to take care of the current heat recovery. That may be one way or another, rather easy to implement in the existent construction.Through the work to increase the efficiency of the gas engine, implement of some external cooling system by heating exchange device. That gives an opportunity to heat (primary) the digester, (but even all internal public areas) with its own superfluous heating.The report shows that if the management group may invest 422 704 crown to implement a heat exchanging device, it gives more space to reduce the need to buy expensive external energy. Gatukontoret´s pay off time, for buying machines, is 20 years, with reservation to calculate with 4 percent internal interest, leads to the yearly mount of 31103 crowns.If Gässlösa increases the gas engine time in (effective) duty approximately (correspondingly) 48 hours a month the entire investment will generate a profit in January in year seven after the implementations.

Delta X : Utveckling av värmeväxlare

Stockholms vattenskärning AB in Kungsängen has through the acquisition of a company begun to design and produce aircraft heaters whose origin is early 1970s which follows a high inefficiency in terms of energy consumption and size.The aircraft heater, which is sold worldwide, serves its purpose for customer satisfaction and has done so ever since it was developed in the 70s.Stockholms vattenskärning AB is now investigating the possibility in making the aircraft heaters more efficient, both in terms of energy consumption but also on a more efficient design with the belief that it would lead them to an edge in the market. The aircraft heater consists of several main components whose function altogether is to keep passenger aircrafts warm while they are on the ground.This project has been limited to the further development of the heat exchanger package which accounts for the conversion of the hot medium to the fresh air being carried in to the aircraft cabin. Work has been divided into different phases in order to create a better understanding of the project range and to make it easier to divide the various elements in the time available, 10 weeks. These phases are literature review, situation analysis, concept generation, CAD, concept comparison and writing reports.After the initial literature review was made, a fundamental theory was written which is essential in understanding the remaining parts of the project.With the theoretical part as support, measurements and calculations were made on the current heat exchange package in a situation analysis to ensure its operation and efficiency.In the concept generation phase, the collected facts from the literature review was used as the basis for creating a matrix. The purpose of the matrix was to indicate the two most suitable types of heat exchangers to develop four new concepts out of.In the CAD phase the four concepts was drawn up and then described with text and images.The last phase is the concept comparison where a concept selection matrix is used to function as a decision basis for further production at Stockholms vattenskärning AB. The four concepts have been developed based on the current heat exchanger and is gradually changed into a design of a cross-flow heat exchanger constructed out of stainless sections. The purpose of this is to have gradual upgrading of the heat exchanger as an option, in order not to saturate the market..

Dose-related selection of Pradofloxacin resistant Escherichia coli

The study evaluated the Mutant Prevention Concentration (MPC) of Pradofloxacin on three Escherichia coli (E.coli) strains, 2 wildtypes and one first-step gyrA resistant mutant. We also measured the value of AUC (Under the Concentration)/MPC that prevents growth of resistant mutants. It is of importance to reach a concentration above MPC that prevent E.coli from developing resistance against the antibiotic.We used an in vitro kinetic model where we added bacteria? and antibiotic. The culture flask was attached to a pump with an adjustable pump-speed.

Simulering av översvämningar i Byälven

Severe floods caused by heavy autumn rains in year 2000 raised the question whether measures to reduce the damage from high water levels, in the area surrounding lake Glafsfjorden and along the river Byälven down to lake Vänern, are possible. One option is to reduce flow resistance along the river and thereby lower the maximum water level a given inflow would cause. Good knowledge of hydraulic and hydrological conditions is necessary in order to estimate the effect of such flow-reducing measures. In order to quantify such effect a 1-dimensional hydraulic flow model has been set up for the river Byälven using the software package MIKE 11. The model is more detailed, especially concerning topography and bathymetry, than earlier models used for studies of the river.

Solvärme till Östersunds Rehabcentrums terapibad : Förstudie av förutsättningar för, - och lönsamhet med, solfångare för att värma terapibadet

This report treats whether it is viable to invest in solar heating to heat the therapy pool at Östersunds Rehabcentrum. The rehab center is owned by the county council of Jämtland and is located on Solliden in Östersund city. The solar heating where supposed to be a complement to the district heating that was heating the pool in the current situation. Later, it however showed that this was not the case. The pool is currently being heated by a radiator circuit that is being heated by the district heating.

Konduktivitet i vattendrag som indikator på sura sulfatjordar

Increasing attention is being given to acid sulphate soils wherever they occur. The problems that leaching sulphate soils gives with significant lowerings of pH and mobilization of heavy metals influence large spectra of our society from fisheries to agriculture to construction. Mapping these soils is consequently of great importance and the methods of doing this is very much lacking in function and precision. This study was therefore carried out to investigate whether conductivity in running water can be used as a simple instrument to identify acid sulphate soils in the catchment. 31 coastal streams in the county of Västerbotten were analyzed for different catchment properties such as occurence of marine sediments and basic water chemistry including conductivity and sulphate.

Mineral composition of New Zealand monofloral honeys

The objective of this study was to determine the mineral content in ten New Zealand monofloral honeys, in order to distinguish whether New Zealand monofloral honeys are a good source of minerals compared to honeys from other parts of the world. The ten monofloral honeys were collected from a local honey factory (Airborne Honey Ltd, Leeston), Clover, Honeydew, Kamahi, Manuka, Nodding Thistle, Rata, Rewarewa, Tawari, Thyme and Vipers Bugloss honeys were been investigated. The water content, water activity, pH, conductivity, colour and mineral content were evaluated. The water activity was averaged for all the ten New Zealand monofloral honeys and set to 0.59 aw, which indicates a high stability and long shelf life as a food stuff. A strong correlation between total mineral content, pH, conductivity and colour was obtained.

Fånggrödor i Norra Östersjöns vattendistrikt

70 % of the lakes and waters in the water district of northern Baltic Sea do not reach the requirements for good ecological status. This is mostly due to eutrophication caused by a too high deliverance of nutrients from agricultural land or effluents. Losses of particulate phosphorus through water erosion contribute to a great extent to this eutrophication. In the action plan for the water district cover crops are mentioned as a measure for reducing losses of phosphorus from arable land. This paper reviews the possible effect of cover crops in the water district and discusses what crop that would be most suitable.

Utvärdering av ett silotorksystem för spannmål utrustat med omrörare :

The aim of this study was to evaluate the stir drying method, for drying of grain during Swedish conditions. The evaluation was done during the harvest year 2004, on four farms with stir driers. The driers were evaluated for their energy consumption, design, stirring effectiveness and how much time the farmer has to spend on every tonne of grain. A comparison was also done with conventional Swedish high temperature driers. Totaly six batches of grain from stir driers were examined, mostly winter wheat, but also barley and wheat.

OMBYGGNAD AV TRAFIKPLATS : Ekhagsmotet i Jönköping

We have the tradition in Sweden to build villas and houses with a wooden framework. It has become natural for us because we have so much forest in our country. Building with wood has advantages, it is easy to process, but also disadvantages, as it is sensitive to moisture.Finland has long made use of the thermal blocks to build villas. It is a type of bricks that are a bit like a sandwich element, with a core of EPS and concrete on both sides of the core material. The concrete is hollow, so that after the walls has been bricked up you pour concrete into the hollow bricks.The issue of this report is to find out if concrete can be an alternative to wood as framework material in villas.

Bestämning av vattenytor med hjälp av Nätverks-RTK och totalstation : Inmätning av Karlbergsån i Grums kommun

This report is presenting an approach that can be used to measure water surfaces in difficult conditions caused by dense vegetation and lack of nearby known points. The objective was to make a contribution to necessary measures for adaptation against floods in Grums Municipality along the stream Karlbergsån, which may occur when persistent rain raises the level of the stream. Along the river there are low-lying areas prone to flooding. According to Grums Municipality, the stream may widen where the water level differences are large, to create a better flow path and to counteract flooding. Grums Municipality was also interested in survey stormwater discharges which may affect the water level in the stream.

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