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957 Uppsatser om Thermal heat losses - Sida 11 av 64

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.

Utvärdering av en väggkonstruktion utan PE-folie : Med en undersökning av hårdvaxolja som diffusions-/konvektionsspärr

District heating covers around 80 % of the heating demand in apartment buildings and 10 % in single-family homes in Sweden. In the year 2010 the total input of energy to the Swedish district heating grids was about 70 TWh, which corresponds to 11 % of the total energy input to the whole energy system in the country. Through the combined production of heat and power the CHP-plants often reaches an efficiency of 90 % from energy in the fuel to produced heat and power. In order to keep the efficiency high it is important for the owners of the plant to have good knowledge about the plants performance at different operation points. Strängnäs Energi AB initiated this diploma work together with FVB Sverige ab in order to come up with a program for short term planning of the production of heat and power at the company´s CHP-plant.The work consists of three main parts.

Cellulosa : en alternativ isolering med hänsyn till brand och fukt?

AbstractThis master thesis was performed at Scania transmission department in Södertälje, where the manufacturing of gears is done. Today a large amount of manual handling is performed between the machining and the hardening process. Most of the manual handling is done at the heat treatment department. The purpose of this master thesis is to give a suggestion on how to reduce or eliminate the manual handling at the heat treatment department. The possibility to use the same packaging throughout the processes will also be investigated.

Värmeslag hos hund : Förebyggande åtgärder, djurägarråd och omvårdnad

The objective of the essay was to identify the nursing care required by a dog suffering from heat stroke and how to educate and advice the owners how to start treating their dog and prevent the condition from occurring in the first place. The essay is based on a literature study. Several databases were searched for scientific research to try find answers to the issues. Keywords concerning the subject were used and mixed in different combinations to sort out the suitable studies. The results of the study indicate that the dog should be cooled by the owner directly after detection. The most crucial issue is to reduce the body temperature as quickly as possible or the morbidity will worsen.

Kravspecificering av avgaspannor

This report describes the work of developing a specification of requirements for Waste Heat Recovery Units. The main part of the paper describes how the work with the specification of requirements has been performed. One specific question to be answered is:What are the customer?s demands in case of properties for the Waste Heat Recovery Units and how is that information collected as an order documentation to suit the business area Oil & Gas?The report begins with a description of the assignment and continues with the aim and background. A theoretical part describes the different areas and methods that have been important during the process.

Energieffektivisering genom förvärmning av flis till kokare med sekundärvärme

The Swedish pulp and paper industry meets higher demand for energy efficiencyi mprovements with increasing energy prices and changes in the Swedish renewable energy certificate system. One action of energy efficiency improvement is by using secondary heat, that otherwise would have been treated as waste heat, for use in a system with lower temperature demands. The aim of this Master´s thesis is to identify possible secondary heat sources in a typical Swedish pulp and paper mill and to investigate what economic benefits the secondary heat will provide when being used for pre heating of wood chips to a kraft digester.The Master´s thesis focuses on three secondary heat sources; dry warm air, warm water and moisture saturated warm air located inside the pulp or paper mill. Two types of kraft digesters are simulated within this study, a typical Scandinavian digester and a modern twin vessel steam phase digester.Due to quality aspects and low temperature level drying is the drying technology with dry warm air rejected. Using warm water in direct contact with wood chips increases the quantity of water to the evaporation plant and thus reduced pulp or paper production and is therefore also rejected.

Analys av off-design prestanda för ett absorptionskylsystem

This master thesis project at KTH is performed in the Mechanical and Aerospace Engineeringdepartment at University of Florida (UF). The thesis is a small part of a gas turbine researchproject where a vapour absorption refrigeration system (VARS) and a high pressure regenerativeturbine engine (HPRTE) are integrated together. The main objective is to build a computermodel of the VARS. The computer model is supposed to be used to analyse the off-designperformance of the VARS and should also be easy to integrate as a subroutine in a more complexsystem model. To model the VARS some knowledge of the absorbent/refrigerant mixture had tobe well known, in this case a mixture of ammonia and water.

Comparative analysis of Thermal Barrier Coatings produced using Suspension and Solution Precursor Feedstock

The research work performed in this thesis has been carried out at the Production Tech-nology Centre where the Thermal Spray research group of University West has its work-shop and labs.This research work has been performed in collaboration with the International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Hyderabad, India.First of all, I would like to express my sincere thanks and gratitude to my supervisors Dr. Nicolaie Markocsan and Dr. Nicholas Curry for their guidance, great support and valuable suggestions without which this work could not have been possible. I would also like to thanks Prof. Per Nylén for keeping faith in me and providing me an opportunity to work at PTC, which is a great place to perform research.

Svinnoptimering VTIS1

The goals of this Bachelors? Thesis were to establish the production loss through the VTIS1 Pasteur at Arla Foods Linköping dairy and then suggest simple but effective solutions to minimize the losses for each production run. If the timeframe allowed it, some of the solutions would be implemented and tested in full production to determine their impact on economic and environmental savings.The very first step of this project was to establish the statistics over what losses there is in the production pipeline through VTIS1, from milk and powders in mixer tanks to finished and packed products in cold storage. Then, when knowing how much product was actually lost and where, those bottlenecks could be pinpointed and examined more closely. At this stage the focus was switched, from the otherwise complicated and broad manufacturing process, to the VTIS1-aggregate, since early data indicated there were quite substantial losses there.In conjunction with this project Arla Foods purchased an absorption photometer-measuring device (OPTEK AS16) that could be inserted straight into the product stream out of VTIS1, allowing real time measurements of its optical density.

Kastrering av frisk tik

In this work we have compiled results from various studies concerning medical conditions that may possibly be avoided by castration and the effects that may occur after castration of the healthy bitch. The work is a literature review but it also includes a summary on the age recommendations for castration of the healthy bitch, castration before or after the first heat and the castration method most commonly used of ovariohysterectomy and ovariectomy. The summary is based on a questionnaire answered by personnel from 20 veterinary clinics and animal hospitals evenly distributed throughout Sweden.The summary showed that ovariohysterectomy was the most common method of castration and the recommendation in age ranged from 6-12 months. Regarding castration before or after the first heat 75% of the veterinary clinics and animal hospitals answered that they recommended castration after the first heat. Literature study shows that there are both advantages and disadvantages of castration of the healthy bitch and that it therefore is important that each bitch get a personal and individual evaluation before a decision is taken concerning a castration..

Påverkan av skogsbrand på litiska arkeologiska fynd ? experimentell simulering av brand

This is a paper about the effects from smoldering fire on lithic objects from an archaeological view. The introduction gives the background to this paper, a short orientation to forest wildfires and why the work is limited to: flint, quartz, quartzite and slate. Material and methods describes the stone materials and the setup that was used in the temperature logged tests with three replications for each type of material. The fuel in the burnings was peat on a bottom of sand. Flint showed a more drastic effect from heat compared with the other materials. Slate seems to have greater tendencies to change to darker colour and luster at lower temperatures than the other materials.

Val av värme- och ytbehandling

Atlas Copco Tools develops and manufactures handheld industrial tools. Heat and surface treatments are used to provide the tools with certain properties. There are no routines for the choice of treatment or for how to specify treatment on drawings. Production documents that are sent for production abroad may not be clear enough. Some treatments are known as trademarks and there are no instructions for how to specify these on drawings and in CAD-models.The purpose of this master thesis work is to create recommendations for the procedure of choosing heat and surface treatment.

Utveckling av lastmodell för Uppsala fjärrvärmenät

The aim of this study was to develop a load prognosis model for Uppsala district heating system to be used as a tool for heat production optimization. The methodwas to build three models for the different customer types; housing, industry andoffices and then scale them for the total system using data from Uppsala districtheating system. The heat load consists of two parts, one that is temperaturedependent and one that is dependent of the social behavior of the customers. Thetemperature part was modelled with an ARX model using an outdoor temperatureprognosis as input signal. The social behavior part was modelled using the mean ofthe social behavior from some days before and additionally by distinguishing betweenweekdays and weekends.

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.

Energiåtervinning från gjuteriprocess till fastighet, undersökning för ökat utnyttjande av spillvärme

This diploma work on D-level is made in cooperation with Varnäsföretagen AB in Eskilstuna. The company performs contract manufactured aluminium goods. This work is a continuation on earlier diploma work in Varnäsföretagen AB. Even if the industry process consumes much energy for melting the aluminium goods, they consume a great amount of oil to warm up the building. The purpose of this work is to examine some places in the building and the process to see how much energy it is possible to recycles to the heating system and reduce the costs for heating.

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