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548 Uppsatser om Carbon dioxide emissions - Sida 16 av 37

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.

Aktivering av en dissolvingmassa med enzymer före en konventionell viskosprocess

In conventional viscose manufacturing, a large amount of carbondisulfide is consumed. This amount has to be decreased to keep the production cost down and to reduce the environmental impact. The purpose with this work was to show if an enzyme treatment of a dissolving pulp could increase the degree of substitution in the viscose so that the amount of carbon disulfide consumed in the process could be decreased. Previous investigations by Kvarnlöf (2007), Engström et.al. (2006) and Henriksson et.al.

Energieffektivitet i datahallar

The number of data centers and their capacity is increasing throughout the world. Theenergy used in these data centers and the emissions from the use are increasing at thesame rate. The total use of energy will double from 2008 to 2011 based on the trends indata centers use. Research in this area says that the emissions from data centers willhave surpassed the level of airline traffic in 2020. The index used today to compare howefficient a data center is, called PUE, is lacking some information.

Livscykelanalys av en gängtapp - Underlag och verktyg för att inkludera livscykelperspektivet i utvecklingsarbetet vid Dormer Tools AB

The aim of my thesis was to do a Life Cycle Assessment (LCA) of an average thread tap that is manufactured by Dormer Tools AB, and to create a practical model that the company can use in order to study other thread taps from an environmental perspective.The method of LCA is used to investigate the environmental effects of a product during its life cycle. This is a gate-to-grave analysis with focus on steel and thread tap manufacturing, coating procedure, use, waste management and transports. Three common coating types were compared separately. Steel manufacturing answers for the highest energy and raw material consumption under the life cycle of the thread tap. Its emissions contribute to global warming, acidification and eutrophication above others.

Assessment methods for corporateresponsibility on the fashion scene : a case study of Hennes & Mauritz, Lindex, Kappahl and MQ

Assessing the outcome of corporate responsibility is often argued to be complicated due to long-term effects and qualitative aspects. Epstein (2008, p.261) establishes that: ?Though many think that sustainability is too difficult to measure, companies have found that unless the impacts are measured, they are commonly ignored in the resource allocation process?. Corporate responsibility is often referred to as a business case, i.e., that social and environmental concern add value to the business (Heikkurinen, 2010; Porter & van der Linde, 1995). Hence, for corporate responsibility to be a business case a strategy, corporate structure and systems, programmes and actions linked to performance measures need to be in place to assess the outcome; environmental, social as well as financial.

Underlag till energieffektiviserande åtgärder i nätstationer

Umeå Energi are working towards a goal, that in the year of 2018, they will be completely climate neutral. As a part of this, one target is to reduce their grid losses by 4 % of the 2012 level, which corresponds to an overall reduction of the grid losses of just over 1.7 GWh. In many residential areas, the distribution grid is designed and rated for electric heating as the heating in the houses. As many of the houses later has been converted to other types of heating, their electricity use has decreased and the total power output from many of the secondary substations has decreased significantly. Because of this, many of these stations today are well oversized, which in turn means that the energy losses in these stations are unnecessarily high.In this degree project, 25 secondary substations have been studied, all located in residential areas in and around central Umeå.

Valsningsteknik för extremt höghållfasta tunna stål

New high strength steels require improved cold rolling techniques. The aim of this degree project was to develop a new and money saving cold rolling technique to manufacture steel strip for saw blades. The work is based on earlier rolling experiments made with a high carbon steel grade at LuCoil Steel AB. The work also focused on the mill requirements to cold roll high strength steels. The results show that LuCoil?s existing cold rolling mill was actually designed for rolling low carbon steel.

Radialtätning till Retarder

This thesis has the overall objective to develop the optimum sealing system between the retarder and transmission. Today, there is a pressure-relief and two radial seals separation between the retarder and transmission. It has been found that carbon residue formation may occur between retarder axle and seal lips with, in some cases, leakage as a result.We have in this thesis tried to explain the phenomenon of carbon residue, how it is formed and why it can be seen just on the seals? A rig test was conducted where we show how friction, speed, transmission temperature and mitigation phases of the retarder affects temperatures in the sealing environment. Factors affecting the coke structure are reported, together with proposals for measures that provide a mitigating seal environment.

Svält vid akut diarré hos hund, beprövad forskning eller gammal vana?

The idea for this project was initiated together with one of the leaders in the forest, paper and packaging industry. To get through an A/R CDM process the company is exposed to the risk of failing the process or that the overall costs will exceed the benefits of the project. This would delete the incentives to invest in GHG removals compared to purchasing emission allowances on the carbon market. The questions that have been raised and needs clarification in the thesis are the following:? From a company perspective, what are the incentives for implementing Forest Clean Development Mechanism (CDM) projects?? What is a likely financial outcome of a reforestation CDM project on degraded land in the Guangxi province of the Peoples Republic of China?? When does an investment like this break even with the cost of buying market based carbon emission allowances? The objective of this master thesis is to carry out a research about the incentives for forest, paper and packaging companies to invest in reforestation through the clean development mechanism.

Etanolmetabolismen ur ett alkoholistperspektiv : Kemin vid nedbrytning av etanol i kroppen, dess betydelse för kroppens kemiska processer i övrigt samt dess betydelse för hälsa och sjukdom

The present study discusses the metabolism of ethanol in the human body from the ingestion of ethanol to the excretion of its break down products water and carbon dioxide. Ethanol is a small molecule, soluble in water as well as in organic solutions. It is quickly distributed to every section in the body, where it exerts a direct toxic effect on the cells. Ethanol cannot directly leave the body efficiently so it needs other metabolic pathways. The molecule is metabolized by oxidation, predominately in the liver.

Regressionsmodellering av dynamiska råemissioner från statiska mätningar

By using steady-state measurements for predicting emissions under a dynamic drive cycle wouldsave a lot of time and money for the exhaust aftertreatment specialists at Volvo cars. The idea forthis thesis has been to investigate if statistical regression models can be used with good accuracy.Questions included are for example if common operating variables such as engine speed, air-fuelratio etc. is sufficient to predict engine-out emissions over the engine operating range with goodaccuracy. Focus was set on the modelling of warm engine, but also the more complex engineheat-up phase was investigated since it is a great contributor to total emissions. While NOxcouldnot be measured because of malfunctioning measurement equipment, only HC, CO andtemperature at inlet of first catalytic converter has been modelled.

SAMMANS?TTNING AV MAKROALGER I SVENSKA ?LGR?S?NGAR eDNA sp?rning och klimatf?r?ndringar

The aim of my bachelor?s thesis is to investigate, through a literature review, changes in the distribution of filamentous algae as well as the general species composition of macroalgae and diatoms in Swedish eelgrass meadows. I have also studied the possibility of tracking these algae and diatoms in eelgrass meadows using eDNA methodology. The focus has been on linking these changes to climate change factors such as eutrophication, temperature increase, and anthropogenic emissions, and how these affect the health of eelgrass meadows and their ecosystem services, such as a carbon sink and biodiversity support. The results show that filamentous algae have increased markedly in coverage in Swedish coastal areas between 1980 and 2021, especially in sheltered bays, indicating that altered environmental conditions favor these fast-growing species. Genetic tracking using eDNA demonstrated that there are functional primers for many species, particularly among brown algae and red algae, whereas green algae require more specific primers due to greater genetic variation.

Bränsleoptimering av befintliga brikettpannor

Intresset för biobränsleproducerad energi har ökat i takt med att kunderna blivit mer miljömedvetna. På grund av detta har efterfrågan på briketter ökat samtidigt som träindustrin har haft det svårt i en sviktande konjunktur. Därför har ett examensarbete utförts i samarbete med E.ON Värme Sverige AB där undersökningar på bränslebyte i pannor avsedda för torra bränslen till fuktigare, stamvedflis har utfört.För denna undersökning har begränsningar införts på övre och undre effekt i form av uppehållstid och slutförbränningstemperatur. Intervallen är enbart beräknade på stamvedflis med 30 och 40 % fukthalt.Undersökning visar att det går bra att elda stamvedsflis i briketteldade pannor utan att emissionerna ökar så pass mycket att villkoren för anläggningarna överskrids om lasten hålls inom vissa intervall. Det möjliga effektintervallet ökar med minskad fukthalt på bränslet.Undersökningen har visat att det är bränslets kvalitet som är den mest begränsande faktorn..

Livscykelanalys - en miljöorienterad rapport

Den textila industrin, en egen värld, är nu under rampljuset som en av de största miljöpåverkande industrierna. Precis som i fallet med många andra industrier så måste textilbranschen intensivt arbeta med att minska sin negativa påverkan på miljön. Slutmålet måste vara att helt balansera uttagen och insättningarna så att man skapar en bransch som blir klimat- och miljöneutral. I denna rapport har en livscykelanalys gjorts på en underställströja från Helly Hansen tillverkad av 99 % polypropylene. Inom denna livscykelanalys har vi noggrant studerat och undersökt fakta för att hitta de processer som har den största påverkan på miljön.

Projektering av en etanolfermenteringsanläggning i pilotskala med Biostilteknologi

AbstractThis degree thesis was made in cooperation with Chematur Engineering in Karlskoga.Many of the environmental issues of today are a result of the motor traffic. Consumption of fossil fuels harms our environmental through formation of carbon dioxide and other greenhouse gases. To get under control with our environmental issues it?s important to find substitutes for oil that are both cheap and environmentally friendly. Ethanol has a long history as a motor fuel and is both enviromentally friendly has a high efficiency.According to the EU commissions directives for motor fuels, 5, 75 % of all the fuels in Sweden should be renewable in 2010.

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