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582 Uppsatser om Borehole Heat exchanger - Sida 13 av 39

Småskalig elproduktion i Arvika

Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state.In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where electricity is in a conventional manner.The purpose with this rapport was to do a basic study for the specific system at Arvika where it?s possible to see the potential production of electricity that follows an installation of a flasbox.The final goal was to introduce an economic analysis of a flashox installation at given conditions.To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present.The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox.

Metoder för lastprioritering i fjärrvärmecentraler

A problem in the field of district heating is the oil burners needed to provide power when a peak load occurs. One possible way of reducing the needed amount of oil is to reduce the power demand for space heating in the district-heating substations when the need for district heating water exceeds a certain limit. This can be done by use of a locally working controller function.In this Thesis the options concerning load priority are evaluated. To evaluate the potential for using controller functions concerning peak load priority an experiment was brought out in a chosen district-heating substation. The impact on the indoor thermal comfort during a heat reduction was also taken into account.

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).

Akustisk mätning av U-värde

This pre-study investigates the possibility of U-value measurements through an acoustic method. A hypothesis about an acoustic model built on acoustic theories combined with U-value theories is presented to answer the questions: ? Can U-value theory be combined with acoustic theories? ? Can the coefficient of heat be affirmed trough an acoustic measurement? The idea for this dissertation begun with a logical idea in mathematical similarity, between the coefficient of heat transmission units and sound intensity units. The U-value theory is based on assumptions such as initial resistance for inner walls and initial resistance for outer walls. The resistance in the material is interpreted through sound intensity theory. The argument is built upon mass law theory, which means if the frequency or thickness of the material layer doubles it implies an increase of sound reduction by 6 dB.

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.

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.

Economizer i bostadsvärmepumpar

I takt med stigande energipriser finner fler och fler det lönsamt att installera värmepump för att reducera sitt energibehov. Värmepumpar har dock svårigheter att tillgodose värmebehovet när utomhustemperaturen sjunker under -10°C. Detta problem kan minskas med så kallade economizerkopplingar, denna rapport jämför de båda economizersystemen flash tank cycle (FTC) och internal heat exchanger cycle (IHXC). Eftersom det har visat sig att vinsterna med economizerkopplingar är som störst då temperaturlyftet är stort är det mest intressant att jämföra dem i luft/vatten värmepumpar. Detta på grund av att övriga applikationer som berg-, jord- eller luft/luft-värmepumpar inte utsätts för samma stora temperaturvariation då utetemperaturen faller.

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.

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.

Konstruktion av värmespridare med grafit för flygelektronik

This master thesis was carried out for Saab Avitronics, a business unit of Saab ABactive in electronic systems for military aircrafts. Reliability and weight are of crucialimportance in this environment. To improve reliability and lower the weight graphitemay be used for electronics cooling. Graphite is an anisotropic material and hasthereof high thermal conductivity in two directions (in-plane) and a relatively lowconductivity in the third direction (through thickness).The purpose of this thesis was to investigate if graphite is an adequate thermalconductor to use in PCB carriers. The carriers support and cool the PCB by divertingthe heat dissipation from the PCB components to the edge.

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