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2244 Uppsatser om Energy measurements - Sida 47 av 150

Värdering av katastrofers miljökonsekvenser

When a disaster occurs the main focus is on the loss of human lives. Here the environmental effects have been in the centre of attention. This work has had two main purposes. The first one was to formulate attributes, variables that together present a complete picture of the consequences that an event has had on the environment. The other main purpose was to investigate how people value the impact that a disaster can have on the environment.

Tubular polyethylene biogas digesters : development and testing of a biogas technology in Malawi to reduce deforestation and support climate change mitigation and adaptation

The aim of the study was to install a biogas system consisting of three tubular polyethylene biogas digesters at a rural household in Malawi and to evaluate the constructed biogas system with regards to relevant system parameters. The purpose was to evaluate if the technology is a possible solution to reduce deforestation and support Malawi in climate change mitigation and adaptation. The study was carried out in the southern part of Malawi in cooperation with the University of Malawi. Locally available materials were used to construct and install the system. Three different feed materials, cow, goat and a mix of cow and goat manure, were used in order to determine which one was best suited to utilise as a digester substrate. After the installation, measurements of temperature, pH, biogas production, biogas composition and system functionality were made. The results of the study show that a biogas system with tubular polyethylene biogas digesters can be successfully installed at a rural household and that the most suitable feed material is a mix of cow and goat manure.

Studie av belagda kolvringarmot plasmasprutat cylinderfoder : Med avseende på friktion och nötningsmotstånd

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

Impulsmätning medelst gradvis deflektion av alla sprayer från högtrycks common rail spridare

A method for measuring the total impulse from a multi hole diesel injector, introduced inprevious thesis work, ?Development of a method and a device for measuring the momentumrate of fuel sprays?, by Mikael Lindström, has been further developed and tested. The conceptis to simultaneously deflect all sprays from a multi hole diesel injector by using a bell shapeddeflector. The fuel sprays are deflected straight down from their initial umbrella angle, andthe resulting deflection force is measured in a thin strained section of the load cell. The strainis given by three strain gauges, with quarter-bridge circuitry for each gauge.

Val av komplementmaterial för våtkompostering av klosettvatten

Emissions of insufficiently treated wastewater, mainly blackwater (i.e. wastewater from toilets), contributes to the eutrophication of lakes and seas. At the same time, blackwater is a fraction with a low content of heavy metals and, after sanitization, it can recirculate plant nutrients to arable land using the liquid composting treatment method. Liquid composting means that organic material is degraded under aerobic conditions. For sanitization, the blackwater needs to be treated together with energy-rich complementary material.

Turbinkretspump system - Kraftvärmeverket i Borås

The Rya power plant in Borås produces district heating, district cooling and electricity. The plant is owned by Borås Energi och Miljö AB and is run by Dalkia Facility Management AB.In order to get the best heat exchange from the district hot water a pair of twin pumps and a turbine circuit pump are used as return pumps. Turbine circuit pumps are used to increase the pressure through the heat exchangers at the power plant. The pumps are in use when the flow is over 2 000 m3 h-1 and during the summer when re-cooling is used to improve the effectivens of the heat boilers.Since the pumps, that are parallel connected, rotating at a fixed rate per minute, the pressure is regulated with regulating valves. This report shows that during the 4,300 hours that the pumps where in use, energy corresponding to 590 MWh was wasted.

Value creation- How can companies optimize the human capital

The thesis aims to examine how companies optimize the human capital from a value creation perspective. The value creation will be related to transfer of knowledge, recruitment, staff turnover and development. The thesis has a deductive approach and six qualitative interviews have been conducted. The results from the interviews will be strengthened with a quantitative data analysis of two measurements; value added per employee and human capital efficiency. The theoretical framework includes definitions of human capital.

Torrefaction of biomass : a comparative and kinetic study of thermal decomposition for Norway spruce stump, poplar and fuel tree chips

Stump biomass is energy rich and stump harvesting for use as fuel become more and more interesting in Sweden. Swedish Forest Agency (2009) has estimated that stump harvesting in Sweden would respond to an annual energy supply of 57 TWh/year. However, stump has not been recognized as a bioenergy resource in Sweden. Suitable methods for pre-treatment of stump are probably of great importance to make it accepted as fuel. It is therefore rewarding to carry out an investigation in this area for stump. This report represents results from a diploma project, which was aimed to develop a fixed bed reactor for experimental study of biomass torrefaction, followed by TG analysis and kinetic modelling employing Ozawa method and different kinetic models including one-step and three-pseudo-component models.

Magnetisk separering av malmpebbles i KA3 - mekaniska konceptförslag : Magnetic separation of ore in KA3 - conceptual design propositions

This has been a thesis work for an bachelor degree at Umeå university. The work has been done at LKAB?s facilities in Kiruna and its main purpose has been to investigate and construct some conceptual designs for replacing a screen with magnetic separation in KA3 concentrator plant. First all information available about magnetic separation was gathered and studies of magnetic separation at the sorting plant and studies of the plant KA3 was conducted. Companies that manufacture magnetic separators were contacted.

Utvärdering av laddningskoncept för lastbilsbatterier

When drivers overnight in the truck lots of electric energy is consumed by heaters, fans, lights and other extra equipment. If the engine is not running, this energy is taken from the lead/acid batteries of the truck which then needs to be recharged during operating hours. The fact that the charge acceptance of the lead/acid batteries is dependent on the temperature makes it hard to fully recharge the batteries at lower temperatures. A negative charge balance can lead to starting problems within a few days use in cold climate.In this thesis work, the effects of different battery charging concept are evaluated on the most common Scania battery (175Ah). A battery model is implemented in Matlab and some simulations of charging are made.

Provmetod för olje- och partikelöverdrag från kompressor till tryckluftssystem

Compressed air is an energy source that is widely used in today's trucks and buses.Compressor located next to the engine supplies the pneumatic system with the compressed air and is lubricated with the engine oil. Some of the oil follows the air flow in both liquid and solid phase. The solid phase, namely the carbon particles are created due to the high temperature in the compression chamber.Oil- and particles carryover softens and destroys the rubber material in the air valves and disturbs the mechanical function of various components in the pneumatic system. In order to reduce oil- and particles carryover is an Air Processing System (APS) set downstream the compressor.No method for establishment of oil- and particles carryover from the compressor exists at the moment. Therefore the filtration efficiency of APS is currently unknown.

Utvärdering av möjligheten att tillvarata energi ur processvatten : En undersökning gjort vid Olofsfors AB på uppdrag av UMIA AB.

The company Olofsfors AB manufactures drive belts for forest machinery, known as ECO-Tracks, and abrasion-resistant steel and cutting edges for graders, excavators and tractors, known as Bruxite and SharqEdges. Manufacturing these products requires the steel to be heated and molded, then submerged in water and hardened. The water used in the hardening of steel is pumped to the process from pits below the floor and then pumped back to the pit after it?s been used. Since the temperature of this water rises after being used to harden the steel the temperature of the pumping pit needs to be adjusted to maintain its setpoint of 21°C.

Association between animal-based measures and register-based welfare indicators in dairy cows : a study of the advisory service "Ask the Cow" and the web report "Animal Welfare Signals"

Animal welfare can be measured in several different ways; for example by using animal-based measurements. It has been shown that register data from the Swedish Official Milk Recording Scheme can be helpful when identifying herds at risk of having poor animal welfare, which led to a development of the advisory service of ?Ask the Cow? and the web report ?Animal Welfare Signals?. The aim of this project was to find out if register data from ?Animal Welfare Signals? can be used as a screening tool for detecting herds at risk of having poor animal welfare and in need of an ?Ask the Cow?.

Byggnadsintegrerade solcellssystem : Solceller som byggnadsmaterial

This thesis aims to identify the building integrated photovoltaic solutions available in the market with respect to general pros and cons of different systems and a technical description of there attachment system. Investigate and provide examples of various building integrated photovoltaic solutions in Sweden and describe the experiences and results of these projects.The methods used to obtain relevant information are interviews with individuals involved in significant projects and a thorough search of different solutions from solar suppliers.The conclusion is that solar energy is needed for a sustainable society. There are endless opportunities regarding BIPV, with many companies with different products and individual solutions. But so far it?s not so customary in Sweden.

Löpmagsförskjutning hos mjölkkor : en besättningsutredning för att identifiera riskfaktorer för metaboliska störningar

The purpose of this study was to find possible explanations to why the studied herd had an increased incidence of abomasal displacements. The incidence of abomasal displacement in the herd was three times higher than the incidence of an average Swedish herd. The cows in this study were fed a total mixed ration. The different parameters studied were: energy content in food, nutritional content in food, body condition scoring, concomitant other diseases, and blood parameters of glucose, fructosamine, cholesterol, insulin, betahydroxybutyrat and free fatty acids. The author?s suggestions to decrease the problems are to decrease the energy content in the TMR to lower the cows? body condition scores in the dry period and changing the content in the TMR to increase the amount of NDF and adding structure in the form of chopped straw.

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