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542 Uppsatser om Carbon emissions - Sida 13 av 37
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.
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.
Utsikten : Hållbara uppvärmningsalternativ för vandrarhemmet på Finnhamn
Finnhamn is a small group of islands in the Stockholm archipelago. At Stora Jolpan, the biggest island, there is a hostel. The main building was built in 1915 and is called Utsikten. The purpose of this project is to on behalf of the Archipelago Foundation (Skärgårdsstiftelsen) find alternative systems that can replace the existing heating system of Utsikten (an oil-fired boiler and electricity heaters) to a system with renewable energy. The alternative system that this project focuses on is a system of solar collectors combined with a wood chip boiler.
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.
Ackumulation av CO2 och CH4 i istäckta boreala sjöar : Hur förändras ackumulationen i sjöar påverkade av avverkning jämfört med referenssjöar?
The aim of this report was to quantify the accumulation of carbon dioxide (CO2) and methane (CH4) in ice-covered lakes in winter (October-March) during three consecutive years, and to assess whether the concentrations of DIC and CH4, as well as the ratio DIC:CH4 differs between years and between lakes affected by clearcutting and untreated reference lakes. Water- and gas samples were collected from four boreal lakes (two affected by clearcutting and two untreated reference lakes) located in Västerbottens inland in spring. The lakes were found to accumulate on average 91, 55, and 84 mgCm-2d-1 during winters 2012-2013, 2013-2014, and 2014-2015, mostly originating from CO2. The concentrations of DIC (autumn and spring) were higher in the affected clear-cut lakes compared to reference lakes for all years, including the reference year (2012-2013) before clear-cutting. No such difference was found for CH4 or the ratio DIC:CH4.
Biobränsle från det jämtländska jordbruket : en studie om lantbrukarnas alternativkostnader vid odling av rörflen
The use of fossil fuels such as coal and gas are a contributor to the global warming. The climate change is a worldwide problem with far reaching consequences that is believed to be very expensive. The United Nations has been introducing a framework convention on climate change. One component of the convention is the Kyoto protocol. The protocol is obligating the developed countries to decrease their emissions of greenhouse gases by 5.2 percent during the time period 2008-2012.
Flygteknik : Konceptstudie av ett obemannat flygplan
Unmanned aerial vehicles (UAV?s) are nowadays greatly appreciated. The advantage over manned airplanes are great since UAV?s can be much smaller and therefore lighter. The goal of this project is to evaluate the performance of an environmentally friendly UAV using only lithium-ion batteries.
Historiska emissioner av bly och arsenik till luft från Åfors Glasbruk och deras konsekvenser för miljön.
Åfors glasswork was a company which started in 1876 and closed in 2012 due to the bad economical situation in the company. After its closure, the glasswork left behind contaminated soil with different concentrations of heavy metals such as, arsenic from arsenic trioxide, a chemical used to remove bubbles during the melting of glass, and lead oxide, a chemical used in the production of crystal glass. Crystal glass?s production occurred under 1921-1971, but emissions of lead into the air from Åfors glasswork continued until 2011, because of the artist Bertil Valliens? artglas was made in Åfors glasswork from 1970?s and onwards.The aim of this study was to estimate how much lead (Pb) and arsenic (As) that were released by Åfors Glasswork into the atmosphere during the operational period of the glasswork in comparison with how much of lead and arsenic were purchased for the company. Added to the assistance of the data from National Archives the variations in the activities of Åfors glasswork could be shown.
Liquid diesel biofuel production in Sweden : a study of producers using forestry- or agricultural sector feedstock
The transportation sector is the only sector of the Swedish society that is still increasing the emissions of carbon dioxide and other green house gases. Diesel fuel represents one of the fuels that contributes to these emissions and the use of diesel fuels is increasing every year. The main purpose of this study was to make an estimation of the current business situation for producers of liquid diesel biofuels in Sweden such as biodiesel, synthetic diesel and crude tall diesel and examine the forces of competition of the industry today and its future prospects. The study revealed that the rivalry among the existing firms was low mainly due to the geographical spread of the companies. Moreover the success of the biodiesel industry was influenced by a long-term guarantee of the tax exempt for biofuels and by the price level of petroleum diesel.
Miljöbyggnad i ombyggnadsprocessen : Miljöcertifiering av Jakobsbergsskolan i Kristinehamn
Climate change is an increasingly widely known concept. In the EU the construction sector is responsible for more than a third of the carbon dioxide emissions and 40 % of the total energy use. In Sweden, measures have been taken to prevent this climate change. By 16 targets, three of which can be linked to the construction sector, Sweden will reduce the negative trend. None of the three goals with relation to the construction sector will however be achieved before 2020.
Implementering av Patientsimulator för Anestesimaskiner
In order to facilitate testing of anesthesia machines a patient simulator has been required by Maquet Critical Care AB. A patient simulator has been developed to reduce expensive and time consuming animal experiments and temporary lab arrangements. The patient simulator has been developed and designed to simulate human lungs with regards to anesthetic uptake, production of carbon dioxide and heating and moisturizing exhaled air.The system comprises a container and a test lung to simulate the volume and the dynamic of the human lung. The simulation of uptake of anesthetics has been implemented by pumping a fraction of the gas from the container through a bypass circuit with an active charcoal filter that adsorbs volatile anesthetics. The flow through the bypass circuit is generated by a pump and is controlled by a linear valve.The resulting performance of the patient simulator has fulfilled the requirements.
Energieffektiviserande åtgärderpå Robertsfors VA-nät : En förstudie av vilka energieffektiviserande åtgärdersom kan göras på pumpstationer och reningsverk
The objective of this work was to introduce measures to reduce energy and water demand at Gävle Söder 17:10. To succeed, this energy audit has been made. The work is based on collected statistics from the property owner Norrporten, measurements, literature review and through consultation with experts in the field. Two models, one for each building, have been created in the simulation program BV2 to estimate the potential of energy measures based on the collected information. The models in BV2 have been verified against the statistics of the energy consumption.With the help of calculations and simulations, seven cost-effective measures have been identified.