Sök:

Sökresultat:

858 Uppsatser om Coefficient of heat transmission - Sida 16 av 58

Kraftvärmeverk i glesbygd - en möjlighet?

Our purpose in this paper is to examine if there is any profitability for a company with a factory in the timber industry to invest in a combined heat and power, CHP. Based on analysis and the results that the paper generates, we will give Derome AB a suggestion on how it is a profitable investment or not to installing in a CHP.By investing in a CHP plant, you can get a high efficiency, which means that companies can use their resources more effectively. The Swedish wood industry has by-products of production that can be used for combustion in their boiler which is an advantage.The essay is a qualitative study where we have a case company, Derome AB. In this company, we interviewed two employees who have knowledge in the study. They have helped us to provide information and data about their business.We chose to use the pay-off- and the net present value method, NPV, to see if there are profitable advantages for the investment.

Solvärme för en skola i Lerum. Studier av olika systemalternativ.

Two elementary schools are now being built in Gråbo (in the municipality of Lerum),Röselidsskolan and Ljungviksskolan, which are both designed with solar thermalcollectors for the schools domestic water heating. During the summer while thelargest amount of solar heat can be generated, the activity hence the domestic wateruse in the schools are heavily reduced. Both schools are connected to the local districtheating system which makes it possible to use the solar collectors to deliver heat tothe district heating.The purpose of this thesis is to evaluate the two systems mentioned above and todetermine which system is more suitable to apply on a school. The building whichconditions were used for this evaluation is Röselidsskolan.A solar heating plant of each system type was dimensioned from the expected andknown conditions of the building. The purpose with the dimensioning was to makethe solar plants replace the ordinary energy source as much as possible.

Dietary fibre composition and sensory analysis of heat treated wheat and rye bran

When grains of wheat and rye are conventionally milled, large quantities of bran classified as by-products are left and are mainly used for animal feed. Bran is a complex material composed of the aleurone layer, nucellar epidermis, a seed coat, a fruit coat and a small proportion of the germ and endosperm depending on extraction rate. The bran fraction consists of approximately 40-50 % dietary fibre which can contribute to increase the nutritional quality of human cereal food. It would also be valuable for the food industry to convert by-products as bran to products with higher commercial values. The aim of this thesis was to analyse the content and composition of dietary fibre of heat treated wheat and rye bran according to the Uppsala method with some modifications in order to analyse soluble and insoluble dietary fibre separately. Half of the bran samples were precooked, dried and roasted and the other half dried and roasted (uncooked).

Beräkning av direktljud genom homogena betongväggar : Densitetens och tjocklekens påverkan på reduktionstalet

Today's urban centers become denser, which contributes to higher demands on sound and noise. It is therefore highly relevant to build homes with good sound environment while maintaining living space. This thesis aimed to reduce the current concrete walls and see how the mass law affects the reduction index value and flanking transmissions. Handmade calculations were calculated according to the Swedish standard SS-EN 21354-1, where only air sound was calculated.Calculations we­­­re performed on wall elements with different weights and thicknesses, and compared with results from Bastian.In Bastian calculations of flanking transmissions were also made, this was made to see the impact of the flanking transmission when changing the mass per unit area. Mass law's impact was examined by flanking transmission and the result shows that they are not affected as long as the ratio between the thickness and the density remains the same.A questionnaire survey was conducted to determine the actual sound experience; this questionnaire was conducted on three concrete buildings in Växjö.

Översyn av uppvärmning

The heating of companies premises is today functional with electrical heating and heating offossil fuel. The energy cost for these kinds of heating in buildings has heavily increased duringthe last years and the influence on the environment has become more visual. This leads to thatenterprises today become more anxious to render energy more effective and find alternativesolutions to their ancient heating systems. This is something that Skandinaviska kraftprodukterAB in Halmstad has become aware of.The purpose with this examination is to find the most cost-efficient and environmental measuresfor the office and workshop premises of SKP AB. Where one of the bigger things is to find agood alternative for their current oil furnace, which was heating the workshop.

Effektivare elanvändning på avfallskraftvärmeverk : Förslag till handlingsplan för minskad elanvändning på Renovas anläggning i Göteborg

This thesis has identified and studied measures to allow for reduced use of electricity in a waste incineration plant in western Sweden. The energy extracted from the waste at the powerplant is utilized and sold in form of electricity and heat. Technical and environmentally the combined heat and power plant is by today's standards among the leading waste incineration plants in the world. The owners are constantly striving to improve the efficiency of the waste incineration plant. They have seen the opportunities for savings in reducing internal usage of electricity.

Undersökning av förskolan Temmelburken certifierad enligt Miljöbyggnad : Termiskt klimat, energianvändning och höjning av certifieringsnivån

WSP building physics in Stockholm has certified the preschool Temmelburken in Bromma with the system of certification Miljöbyggnad. The rating of the building became BRONZE. In this thesis the preschool has been investigated with respect to the three areas: thermal climate, use of energy and improving of the level of certification. The thermal climate at the preschool has been investigated by a questionnaire survey and by measurements in order to do comparisons between the results from the two investigations as well as with the results of the simulations that WSP has done at the certification of the preschool. The differences between the results from the simulations and the questionnaire survey for winter as well as from the measurement performed with a comfort meter the 19th of March are concidered to be reasonably small since they give rise to the same rating according to Miljöbyggnad.   Operational data for the use of energy for the preschool have been obtained in order to do comparisons with simulations performed by WSP and Svenska Besiktningar AB. The comparison shows that the simulated values for the specific use of energy are lower than what the real specific use of energy would be for the preschool, since just the operational data for the heat energy is higher than the simulated values. At the investigation of the possibility of improving the level of certification it was found that the rating of the preschool can be raised from BRONZE to SILVER by improving the ratings of the ?thermal climate summer? and the ?daylight?.

Inventering av processvattenbalans : fastställande av fjärrvärmedistributionens läckage inom Vattenfall Värme Uppsala AB

Heat is distributed to the district heating customers through pipes with water as a heat carrier. The district heating system is complex. To decide what is leakages from the district heating net versus what is the water consumption of the plant, is difficult. Therefore, the purpose of this master thesis is to establish a model where the district heating net?s leakages but also the water consumption of the plant can be followed daily. The project is performed at Vattenfall´s district heating power plant in Uppsala. Information is gathered through discussions, drawings of the plant and guided tours of the plant.

Utveckling av en ny tillverkningslina

This report contains results of our study at CTC in Ljungby. CTC produces heating products such as boilers, heat pumps and additional products to their heating systems.The purpose of the report is to make a proposal how CTC will supply their new production line for heat pumps with materials. The proposal includes a production layout and a scheme for how to place the material in the production storage.The new production line will produce two different products and both of them have several variants. The line will also have a mixed flow, so the products can be produced in a random order. These conditions demand that the production line has great flexibility and that the material to all the variants can be stored in the production storage.With these conditions as input we made a layout proposal to the company.

Low Temperature Waste Heat Solutions : with proposals for energy technological actions based on Scania?s building 64

The report comprises two separate parts:part 1:  Temperature needs for district heating in the paint shop for axles in building 210part 2:  Energy and low temperature waste heat solutions in heating and cooling systems for   building 64 with surroundingsThe paint shop for axles in part 1 has air quality requirements in places for coating of axles. Toachieve desired air properties there are different process ventilation systems, which consist ofventilation coils for heating and cooling, plus air humidifier. The ventilations coils for heating usedistrict heating. Today the ventilation coils use water of 100°C to achieve necessary air demands inthe coating boxes. This part of the report investigates whether the existing system would achievethe air requirements with a water temperature of 75°C instead of 100°C in the ventilation coilsduring the coldest parts of the year.

Produktutveckling av mobil förstahjälpenstation

This thesis is about a part of the marquetrytechnique, scorching. Scorching is made by heating up something, put a veneer into the heated substance and make a controlled burning. This technique is old but still used today and have according to me great potential for development. In my work I wanted to give the scorching greater room then I earlier have seen. I wanted the scorching to be the dominant ingredient for a decorative element in a piece of furniture or an interior.

Att beskriva och jämföra en expertgrupp och intensivvårdssjuksköterskors överensstämmelse i att detektera delirium hos intuberade, respiratorbehandlade patienter med sedering/analgesi, före och efter en utbildningsintervention : En kvasiexperimentell stud

The aim: was to describe and compare a group of experts and critical care nurses' agreement in detecting delirium in intubated, ventilator treated patients with sedation / analgesia, before and after an in house training intervention with the instrument Confusion Assessment Method for the Intensive Care Unit (CAM-ICU).Method: A quasi-experimental study, one group pretest - posttest design. A convenience sample of 17 critical care nurses in a general intensive care unit included. To detect delirium the instrument CAM-ICU was used, 21 paired tests before and 22 after an educational intervention.Main Results: The results showed that after an in house training intervention sensitivity and kappa coefficient improved of the characteristic 1 "acute onset and fluctuating course," an improvement that was significant. In other features, and overall values were signs of numerical improvement and deterioration in sensitivity, specificity and kappa coefficient but no significant change.Conclusion: Implementing a new instrument for detecting delirium in clinical practice requires education and follow-up. A small sample of critical care nurses with varying ability to use the new instrument and the fact that patients' status may change rapidly making it difficult to draw any conclusions from this study.

Energieffektivisering av kulturhistoriska byggnader : Energi och klimat i Lekaryd kyrka

Detta examensarbete syftar till att utreda inneklimat- och energisituationen i Lekaryd kyrka. För att göra detta har klimatmätning genomförts, samt simuleringar med datorsimuleringsprogrammet IDA ? Klimat och energi. Kyrkan har höga energikostnader och för att få kännedom om energiförlusternas storlek och fördelning, har en kartläggning av kyrkans energiflöden genomförts i syfte att fastställa dess energibalans. Målet är att resultaten från klimatmätningen och datorsimuleringarna ska kunna användas som underlag vid utarbetande av åtgärdsförslag för en lönsammare och ur bevarandesynpunkt skonsammare drift av Lekaryd kyrka.

Hydraulisk och termisk grundvattenmodellering av ett geoenergilager i Stockholmsåsen

Geothermal energy can be extracted from an aquifer, where the groundwater is used as heatexchange medium while heat and cold are stored in the surrounding material in the aquiferand to some extent in the groundwater. Application of aquifer storage for the use ofgeothermal energy is mainly used in large scale facilities and is limited to sites with suitableaquifers in the form of ridges, sandstone and limestone aquifers.Löwenströmska hospital in the municipality of Upplands Väsby, north of Stockholm, islocated nearby the northern part of the Stockholm esker. This means that it can be profitableand environmentally beneficial for the hospital to examine the possibilities of aquifer storagein the esker material next to its property.The purpose of this master thesis has been to investigate if geothermal energy storage with aseasonal storage of heat and cold can be applied within Löwenströmska hospital?s propertyarea using groundwater modeling. A hydraulic groundwater model was constructed inMODFLOW based on a simplified conceptual model of the groundwater system.

Analys av PWM-mönster i Matlab

One of ABB Power Systems´s business areas is HVDC (High Voltage Direct Current) technology. HVDC is used for transmissions for both short and long distances. One of Power Systems?s products is called HVDC Light. HVDC Light is a relatively new technology for power transmission, but have before only been used for motor drives applications.

<- Föregående sida 16 Nästa sida ->