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433 Uppsatser om Particle-emissions - Sida 16 av 29
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.
Optisk sortering av matavfall : en jämförelse med en minskning av svinnet
The purpose of this study is to compare the energy related and environmental consequences of implementing optical sorting as a means of waste collection with those of reducing food waste. In addition to studying the possibility of implementing optical sorting in downtown Stockholm, the yielded amounts of energy from waste collection and reduced wastage will be calculated. This is done by way of literature reviews and interviews. The amount of energy that can be generated through optical sorting and biogas production via anaerobic digestion in downtown Stockholm is 29-44 TJ/year, compared to 118 TJ/year saved by completely eliminating food waste. The generated biogas can replace fossil fuels, but the required food waste contributes to increased greenhouse gas emissions as well as reduced bio diversity and eutrophication during the wasted food?s lifecycle.
Biomass losses during short-term storage of bark and recovered wood
Storage of biomass is associated with problems like heat development, biomasslosses, and reduction of the fuel quality. Certain processes such as biological- andchemical degradation are responsible for these storage problems. This master?sthesis was carried out at Vattenfall Research and Development AB and is alignedtowards quantifying the biomass losses from short-term storage (1-2 months) ofbark and recovered wood. The biomass was stored in outdoor piles during differentseasons, campaign 1 (summer) and campaign 2 (autumn).
MCNP-modell för beräkning av neutrondos och DPA på reaktortanken vid Ringhals 2
In this report an MCNP (Monte Carlo N-Particle) model is described for the reactor vessel at Ringhals 2. The model is validated against the specific activity in neutron dosimeters, extracted in 1977, 1984 and 1994. The validation showed that the calculations of the model are within the requirements of a maximum of 20 percent uncertainty for every neutron dosimeter except one, extracted after the first cycle. The uncertainty of this cycle was mostly due to the operation data rather than to the MCNP model.The model has been used to investigate various questions concerning radiation damage. The reliability of the traditional measure of radiation damage, fast neutron flux (En > 1MeV) has been evaluated. This has been done by taking the ratio for this and another measure of radiation damage, DPA (Displacement Per Atom), for various positions and layers.
Mätning av Emissioner från en Diesel Motor under Transient Driftförhållande
Transient driftförhållande blir allt mer intressant för forskare och tillverkare och de största svårigheterna är att minska emissionerna utan att påverka bränsleförbrukningen eller motorns respons vid gaspådrag negativt. Huvudmålet med det här examensarbetet var utvärdera olika metoder för att mäta NOx och antal partiklar med hög tidsupplösning för att möjliggöra studier av emissioner under transient driftförhållande.I arbetet har en Horiba MEXA 120NOx NOx-sensor studerats med avseende på linearitet, mätsäkerhet och responstid. Försök för att öka noggrannheten har också gjorts genom att kompensera för varierande skalfaktor för utsignalen och för responstiden.Ett spädsytem har arbetats fram för att ge hög tidsupplösning och god repeterbarhet. I detta ingick en Rotating Disc spädare och en två-stegs Dekati spädare. Spädsystemet var kopplat till en TSI Ultrafine Condensation Particle Counter 3025 A (CPC) och var nödvändigt för att hålla koncentrationen inom det mätbara området.
Kvantfysiken och den nya myten? : En studie av Fritjof Capras och Danah Zohars böcker om kvantandlighet
This study is about quantum physics and the role it can play in a religious perspective. I intend to examine how moderna physics may be related and understood as New age and Myths. My material consists of two books in the new age genre: "The Tao of Physics" by Fritjof Capra and "The Quantum Self" by Danah Zohar. My first two question to these books are which 1) religious and 2) scientific content they have. My other questions are too 3) investigate and demonstrate how these books are new age and 4) to exanine how the books can function as myths and adopt mythical features.
Ha?llbarhetsredovisning i bostadsfo?retag : En rekommendation
This project was conducted on behalf of the organization SABO (Swedish Association of Public Housing Companies). The aim of this project was to investigate which relevant environmental aspects and indicators there are for housing companies to present in their sustainability report. The project consists of three main goals: to decide if there is a need for common guidelines when conducting a sustainability report, determine appropriate environmental indicators and to create a simple model of how the companies can present them. This was done by a literature study, analysis of 13 sustainability reports and interviews with seven housing companies. The result of the project suggests that there is a need for common guidelines to, among other things, make it easier to make a comparison with other companies.
Bulleremissioner från vertikalaxlade vindkraftverk
Wind power in Sweden is expanding in response to the government's decision that 49% of Sweden's power should originate from renewable energy sources by the year 2020. Problems with noise and sound emissions related to wind turbines are a constant argument against the wind power expansion and this paper means to examine if vertical axis wind turbines might be a viable alternative to the conventional horizontal design for noise sensitive areas. In order to determine factors like difference in frequency, noise propagation and noise emission level, measurements of both horizontal and vertical axis wind turbines have been completed and the data analyzed with MATLAB. It is shown that there is a difference in how the noise from the two types of turbines propagates due to avariation in the frequency spectra of the emitted sound. It is also shown that vertical axis wind turbines generate a lower sound emission with less intensity inthe lower frequencies..
Priset är inte allt - en studie av svenska storföretags finansiering
This thesis describes how large Swedish companies finance their debt and identifies some factors that affect their decisions. The study is based on 10 well-known companies of which 9 are listed on Nasdaq OMX Nordic. The results show that the companies display several similarities concerning their debt structure and the factors which their choices are based upon. All companies in this study primarily use corporate bonds for their long-term borrowing, commercial papers for the short-term borrowing, and bank-facilities as back-up. There is a tendency that smaller companies in larger extent use bank-loans for long-term borrowing due to larger emissions costs when using market financing.
Energy from municipal solid waste in Chennai, India : a feasibility study
Solid waste management is one of the most essential functions in a country to achieve asustainable development. In India, it has been one of the least prioritized functions during thelast decades. The most common ways to treat waste in India today are open dumping anduncontrolled burning. These methods are causing severe environmental pollution and healthproblems. India is one of the world?s largest emitter of methane gas from waste disposal.Since methane is a strong greenhouse gas, even small emissions have large impact on theclimate.
Optimalt ekologiskt : att gestalta praktfulla parker som kan skötas på ett hållbart sätt
This is a graduate work at the Swedish University of Agricultural Sciences, The Department of Urban and Rural Development, Ultuna. The purpose of this paper has been to find out and describe principles for designing parks that offers good recreational and aesthetical values and require little amount of carbon dioxide emissions during their maintenance. The purpose has also been to see if it's possible to use city wastewater in some extent to assure the plants water supply and to find other means to make it less necessary to use purified water for watering.
Recently made studies as well as older ones show how important green areas are in dense city structures both from a health and a climate perspective. Trees and other plants adsorbs different forms of air pollution and can also lower the temperature in the surrounding area through their transpiration.
VTA-aggregatet : En undersökning av driftegenskaper och funktion vid slowsteaming.
Turboaggregat med variabel geometri har länge funnit hos automobiler, men det dröjde ända tills 2008 innan det första dök upp på ett fartyg. Syftet med denna undersökning har varit att kontrollera om de fördelar som Man B&W hävdar att VTA-aggregatet skall ha stämmer, samt att undersöka om VTA-aggregatet kan lösa de problem som uppkommer i och med att man kör med reducerad fart, s.k. slowsteaming. För att undersöka detta har jag bedrivit litteraturstudie, med insamling av data mestadels från Internet.Resultatet av undersökningen visar på att ett VTA-aggregat kan minska bränsleförbrukningen och vissa emissioner vid reducerad fart jämfört med en konventionell turbo av samma storlek. Den minskade bränsleförbrukningen leder i sin tur till ekonomiska vinster.
Massbalansmodellering av fosfor i ett åländskt kustområde : en utredning om lokaliseringen av Lotsbroverkets utloppsledning
This report is commissioned by the Water and Sewage Agency in The City of Mariehamn, Åland. The basic aim is to investigate positive or negative effects of a relocation of the sewage pipe from a wastewater treatment plant, Lotsbroverket. The environmental licence of Lotsbroverket is to be revised and The Environmental Appeal Board at Åland?s Government and Administrative Board has made demands that several possible locations in an outer water area should be examined. The present location of the sewage pipe is in Svibyviken, which has been classified as an ?inner water area?.The objective of this work is to study to which extent the nutrient loading from Lotsbroverket influence the environmental conditions in Svibyviken, and to investigate the suitability of different locations of the wastewater pipe from Lotsbroverket.The way a coastal area looks, i.e., its morphometry, determines to a large extent its ecological characteristics.
Undersökning av luftkvaliteten vid småskalig biobränsleförbränning i två kommuner med modellsystemet VEDAIR
An Internet application, VEDAIR, for estimation of air quality in regions with small-scale combustion of bio fuel has been developed by Swedish Meteorological and Hydrological Institute with financing from Swedish Energy Agency and Swedish Environmental Protection Agency. The model contains user interface and a coupled model concept where concentrations of atmospheric pollutions are calculated for regional, urban and local contributions. In this report the model is described and a first study of air quality considering PM10 (particles with a diameter less than 10 µm) in two Swedish municipalities, Vänersborg and Gnosjö, is introduced.According to the result, there are areas with poor air quality even in smaller Swedish municipalities, mostly due to high emission from buildings with older wood heating furnace without hydraulic accumulator.In Vänersborg three areas were analysed in VEDAIR for the year 2003: Vargön, Mariedal and the downtown district. In the whole municipality the upper evaluation threshold for PM10, which is defined as 14 µg/m3 for annual average, was exceeded due to background contribution of particles. In all areas, however, the concentrations of PM10 were less than the environmental quality norms.
Utveckling av ett hjälpmedel för träning och utvärdering av förare av tunga fordon
The purpose of this master thesis is to evaluate how internal vehicle information inScania buses and trucks can be used for evaluation of driver performance regardingfuel economy, vehicle wear, traffic safety, emissions and cargo damage. To someextent it was examined whether this information could be used for training the driverto a better driving style. In addition, a prototype for such a system was developed.By first defining what distinguishes a talented driver and how he/she differs from apoor driver, followed by a study of the internal vehicle communication, a system thatin real-time gathers and interprets vehicle data could be developed.The resulting system can with reasonably high reliability detect a number of trafficevents (such as braking, lane changing or hilltops). At each such event, the driver?sbehaviour can be evaluated.