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219 Uppsatser om Greenhouse gases - Sida 7 av 15

Förbehandlingstekniker och LCA för rötning av organiskt avfall : Modellkonstruktion och Utvärdering med ORWARE

The goal of this master thesis project was to develop computer models of some plausiblepretreatment techniques and to assess the potential benefits/costs of using pretreatment andanaerobic digestion for waste management of organic waste from a system perspective. Forthis purpose a computer program called ORWARE has been used. ORWARE (organic wasteresearch) is a program for making life cycle assessments of waste management. As the mainpart of the project work the ORWARE system has been provided with three new models ofpretreatment techniques. The additions consist of: One model of pretreatment with ultrasound,one model of thermal hydrolysis and one model of a screw press.

El Niño Southern Oscillation och dess atmosfäriska fjärrpåverkan.

This paper is a literature study aiming to describe scientists newest theories andknowledge concerning the El Niño and Southern Oscillation. Firstly I have described the?normal? conditions with rising and sinking air in Hadley- and Walker-cells in theequatorial Pacific and from there moved on to explaining the reversed circulation patternsand higher sea surface temperatures (SST) leading to rising air and anomalousprecipitation in eastern Pacific constituting the El Niño phenomenon. My outermostinterest regarding El Niño has been the associated teleconnections, especially in nontropicalareas. I have described the El Niño effect on the Indian summer monsoon, ontropical cyclones and on storms and precipitation on higher latitudes.

Ha?llbar sockerro?rsodling fo?r etanolframsta?llning i Brasilien : Hur slagkraftig a?r dagens ha?llbarhetscertifiering och kan den fo?ra?ndra mark- och vattenpa?verkan fra?n odlingarna?

Climate changes today are mainly caused by anthropogenic activities and the increased emissions of Greenhouse gases to the atmosphere and this has raised questions on how to reduce the usage of fossil fuels. Ethanol is a good alternative to conventional gas and has been used in Brazil since the 1970 ?s. In Sweden several newspapers has written about the poor working conditions on many farms thus making the Swedish company SEKAB design a certification for their ethanol to ensure that it can be considered to be a sustainable alternative.Furthermore WWF has developed a certification tool called Bonsucro in cooperation with Coca Cola, Ferrero group, BP and Shell. This is due to the fact that no global certification tool has been available up until now.

Utveckling av ett provtagningssystem för alkohol och aldehyder i fordonsemissioner.

A system for sampling of alcohol and aldehyde from diluted exhaust gases from vehicles powered by ethanol has been developed and tested. The major part of the work has been research of earlier work in the field and the construction of the sampling system.The part of the system constructed for the measurement of alcohol has been shown to work, however, more test should be performed. The part of the system constructed for the measurement of aldehyde was tested parallel to a commercially available system, based on the same principle of measurement, and has been shown to work well.Determination of the concentration of gaseous ethanol using a FID has shown the since earlier known fact that a FID is not able to measure a correct concentration of ethanol. Furthermore it has been shown that high concentrations of gaseous ethanol can not be kept in a bag more than a few minutes without a substantial decrease of the measured concentration..

Brännkammare för träpulver : Teoretisk analys och praktisk försök

The thesis describes a completely new biofuel system to generate particle-free heat from combustion of ash-containing biofuel particles at high temperatures.The suggested system gives opportunities to introduce biofuels in new areas.Main components in the suggested system is a heat radiating combustion chamber intended for pulverized wood, combined with regenerators to extract heat from flue gases and simultaneously preheating the combustion air.The thesis contains a description of the suggested system, theoretical considerations, calculations regarding the combustion, and includes results from tests performed.The results from calculations and tests performed concludes that the system is workable and possible to apply..

Energisystemanalys av ABB AB LV Motors

With a larger awareness of the climate changes and increasing electricity prices, energy efficiency measures in the industry have become more common. By rationalize the activity and by the same time decrease the emission of Greenhouse gases the company can both save money and reduce negative environmental impact. For the Swedish industries the electricity price have traditional been relative low, which has resulted in a considerable larger usage than other European countries. By a deregulation of the European electricity market the electricity price will level off between the countries, which will cause a higher electricity price in Sweden than we are use to. To prevent that the Swedish industry don?t lose competitiveness against the other European countries, it will require energy efficiency activities in all different forms.ABB Sweden has decided to decrease their total energy usage with five percent in two years.

Underlag till klimatledningssystem för skolor

The climate issue is a significant question, and the problem is mainly caused by human activities. Everyone can help to counteract the enhanced Greenhouse effect by reducing the amounts of energy they use and by not consuming more products then they need.Schools are some of societies many consumers and therefore contribute to the Greenhouse effect. The School also has an important task; to teach and disseminate knowledge and information about the climate and the environment. According to the Swedish National Agency for Education, Skolverket, must all schools regularly consider the environment and sustainable development throughout the entire education process. Unfortunately, this is not the case for many schools in Sweden today.One of many tools that can be used to coordinate environmental work and initiatives, and also to make it more efficient, is environmental management systems.

Förbränning av träpellets och pelleterad halm i en 40 kW rosterreaktor

The project focus on combustion of softwood pellets and pellets in a 40 kW grate fire reactor at TEC-Lab. Dept Applied Physics and Electronics at Umeå University. Experiments were performed at four primary airs to fuel ratios (0.7 to 1.3), where aspects such as temperature profile, levels of gases (CO and NO), sintering-/-slagging and unburned fraction of the ashes were studied. Four different fuel loads were used for wood pellets (10, 20 and 30 kW) and one fuel load for straw (10 kW). Combustion of straw proved very difficult to ignite, and also led to other combustion-related technical problem such as slag formation due to the relatively low melting temperature-/-slag temperature of the straw.

Design av en ejektorspädare samt ett system för partikelmassmätning av dieselavgaser

This master thesis was a subtask of a project called EMIR-1. The goal with the thesis was tobuild a system for particulate mass measurements in one of the engine test cells at KTH. Theparticulate mass measurements are planned to be measured with a TEOM.The exhaust gases must first be diluted with air before the sample is sent to the TEOM.Therefore an ejector diluter for this matter also was designed and evaluated in the thesis.Emissions measurements have been done both with and without dilution to determine thedilution ratio. Tests have been done for different speeds and loads.Problems with stability of the dilution ratio have been an issue throughout the process andpressure pulsations in the exhaust pipe are believed to be the cause. More tests have to be done tomake sure that this is the problem.One idea is to make the inner diameter of the diluter nozzle smaller and see if it changes thedilution ratio stability.

Elevers tankar om klimatförändringar

This work examines the students´ thoughts on climate change with a focus on carbondioxid through photosynthesis and the carbon emissions from cars. The study is based on two subject areas, one with a focus on enhanced greenhouse effect, and the other focusing on photosythesis. The survey was conducted by means of qualitative interviews with students in grades four and six. The results describe that student´s understanding for photosynthesis and the carbondioxids function for photosynthesis doesn´t change significantly from grade four to grade six. I have divided the students inte three levels based on their understandingof the various fields, and their use of adequate concepts.

Avgång av lustgas från luftningsprocessen på Käppalaverket

The requirements for wastewater treatment plants (WWTP) are gradually increasing, partly because of higher incoming loads, which in turn require a more efficient treatment process. In parallel with environmental and economic goals there are also desires to lower energy consumption without compromising the wastewater treatment. Furthermore, there is a demand on WWTP´s to alter eutrophication in aquatic systems through better nitrogen and phosphorus removal. An increasing number of WWTP´s have acquired biological nitrogen and phos-phorus removal. A by-product of this type of biological treatment is the formation of nitrous oxide, which is a potent greenhouse gas.

Deloittes konkurrensstrategier : Försäljning av ekonomisk fastighetsförvaltning åt bostadsrättsföreningar

The aim of this study is to find out in which way the education about climate in school is taught and how the students experience the world situation today. There are various theories about the greenhouse effect and its origin and these theories should be addressed to ensure that students get a broader understanding of how climate change occurs. This includes the natural phenomena and also the human impact on climate change. Students in school are a source of concern that only human are the cause of global warming, and know little or almost nothing about the natural phenomena of global warming.  I will mention what has emphasized in the national steering documents in the case of environmental education at school.I have used a qualitative method, where interviews and document analysis were used as techniques. The interviews took place with five students in ninth grade and with three science teachers in the same school..

Personlighetsskillnader mellan gymnasielärare och blivande gymnasielärare : Differences in personality between high school teachers and future high school teachers

The climate issue is a significant question, and the problem is mainly caused by human activities. Everyone can help to counteract the enhanced Greenhouse effect by reducing the amounts of energy they use and by not consuming more products then they need.Schools are some of societies many consumers and therefore contribute to the Greenhouse effect. The School also has an important task; to teach and disseminate knowledge and information about the climate and the environment. According to the Swedish National Agency for Education, Skolverket, must all schools regularly consider the environment and sustainable development throughout the entire education process. Unfortunately, this is not the case for many schools in Sweden today.One of many tools that can be used to coordinate environmental work and initiatives, and also to make it more efficient, is environmental management systems.

Oosporbildning av Phythophthora infestans i potatis och bägarnattskatta

Potato late blight is one of the most important potato diseases worldwide. The disease is caused by an oomycete called Phytophthora infestans. The host range of P. infestans includes potato (Solanum tuberosum) and hairy nightshade (Solanum physalifolium). Hairy nightshade has recently established itself as an important weed in the southernmost part of Sweden.

Förskollärares kunskap om stress och stresshantering bland barnen på förskolan

This work examines the students´ thoughts on climate change with a focus on carbondioxid through photosynthesis and the carbon emissions from cars. The study is based on two subject areas, one with a focus on enhanced greenhouse effect, and the other focusing on photosythesis. The survey was conducted by means of qualitative interviews with students in grades four and six. The results describe that student´s understanding for photosynthesis and the carbondioxids function for photosynthesis doesn´t change significantly from grade four to grade six. I have divided the students inte three levels based on their understandingof the various fields, and their use of adequate concepts.

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