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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Scania’s Packaging Network : Analysis of the Environmental Impact of Alternative Fuels and Modalities Within the Transportation Network

Astori, Pietro, Guðmundsdóttir, Jóhanna Blöndahl January 2022 (has links)
In a fast-moving world with high demand for deliveries of various goods, the need for high performing transportation systems and networks has grown rapidly. As a reaction, the number of trucks has increased, which together with other transport solutions to cover the need has caused a growth of CO2e emissions. Sustainability awareness has pushed companies to consider and implement more sustainable transportation solutions to reduce the environmental impact from transport. The purpose of this study is to analyze and identify the root causes of CO2e emissions in a transport, delivery network. An understanding of the common characteristics of transports causing the highest levels of emissions is provided with an analysis of distances, modalities and fuel types. Additionally, alternatives are simulated to compare the current network to a system with different solutions implemented. The study was performed by analyzing available literature of intermodal transportation systems, alternative fuel types and different modalities. Data for a full year was collected from Scania AB, cleaned and analyzed to identify the type of transport to study further. The characteristics were identified by forming geographical regions based on location and available infrastructure, divide the transports by legs and distances, and sort the transports by fuel types and modalities. As a result, several flows were identified as examples representing the network where the effects of making changes could be most accurately identified.Simulations were performed for exemplary flows providing results for four out of seven regions in the network. Available infrastructure for different modalities was considered for each region and alternative fuel types researched. Considering the possibilities within the regions, each flow was simulated with the available solutions in the region. Additionally, infrastructure potentially developing in the near future, was considered as an alternative in cases where current availability is limited.The results from the simulations were unambiguous for intermodal transportation systems in the cases where electric rail was utilized over any mean of truck transport, regardless of the fuel type. Road transports run on Diesel were used as the baseline for the simulations as it is the highest utilized fuel type. Simulations of road transports on alternative fuels also provided a positive result for CO2e emissions as they decreased in all cases. / I en snabbföränderlig omvärld med en hög efterfrågan av olika varor har behovet av högpresternade transportsystem ökat drastiskt. Som en reaktion på detta har antalet lastbilar ökat signifikant vilket i sin tur, tillsammans med andra transportlösningar som ska täcka det växande behovet, har lett till ökande CO2-utsläpp. En ökad medvetenhet inom hållbarhet har tvingat företag att överväga och implementera mer hållbara transportlösningar för att minska miljöpåverkan inom transport. Syftet med denna studie är att analysera och identifiera grundläggande orsaker för CO2-utsläpp inom ett transport- och leveransnätverk.En förståelse för de gemensamma egenskaperna inom transport som orsakar de högsta nivåerna av utsläpp anges genom en analys av avstånd, modaliteter och typ av bränsle. Dessutom är alternativa lösningar simulerade för att jämföra det nuvarande nätverket mot ett system med andra implementationer.Studien genomfördes genom att analysera tillgänglig litteratur om intermodala transportsystem, alternativa sorter av bränsle och olika modaliteter. Data för ett helt år samlades in från Scania AB, rensades och analyserades för att identifiera vilken form av transport som skulle studeras vidare. Egenskaperna identifierades genom att bilda geografiska regioner utifrån läge och tillgänglig infrastruktur, uppdelade i längre och kortare sträckor, samt genom att sortera transporterna efter bränsletyp och modaliteter. Som ett resultat identifierades en grupp av flöden som exempel, vilka representerade nätverket och där effekterna av att göra förändringar kunde anses mest exakta. Simuleringar för exempelflöden utfördes och gav resultat till fyra av sju regioner inom nätverket. Tillgänglig infrastruktur för olika modaliteter övervägdes för varje region och olika bränsletyper undersöktes. Med tanke på de olika möjligheterna inom regionen simulerades varje flöde med de tillgängliga lösningarna i regionen. Dessutom ansågs infrastruktur som skulle kunna utvecklas inom snar framtid som ett alternativ i fall där nuvarande tillgänglighet är begränsad. Resultaten från simuleringarna var entydiga för intermodala transportsystem i fall där elektrisk järnväg användes i stället för lastbilstransport, oberoende av bränsletyp. Vägtransport som drivs med diesel användes som referens för simuleringarna eftersom det är den mest använda typen av bränsle. Simuleringar av vägtransport på alternativa bränsletyper gav också positiva resultat för CO2-utsläpp som minskade i samtliga fall.
72

Characterization of Vehicular Exhaust Emissions and Indoor Air Quality of Public Transport Buses Operating on Alternative Diesel Fuels

Vijayan, Abhilash January 2007 (has links)
No description available.
73

Analýza nákupu CNG vozidel skupinou RWE v České republice / Analysis of the vehicles on compressed natural gas purchased by RWE CZ Group

Bartejsová, Vladimíra January 2009 (has links)
This paper analyses the purchase and operation of vehicles on compressed natural gas. It contains a definition of Compressed Natural Gas (CNG) and discusses the various phases of its use in transport. It indicates the differences of this alternative fuel compared to traditional fuel such as gasoline or diesel. Then it focuses on the main reasons to support the use of compressed natural gas transport and talks about the legislation which has a major role in the development of alternative fuels. Then it specifies the disadvantages which can be associated with its use in transport. The last section includes an analysis on the specific example of the RWE CZ Group, which compares the different costs for compressed natural gas vehicles and vehicles which run on conventional fuel. Specifically the cost per kilometer of vehicle, CO2 emission and purchase price are given for comparison.
74

Análise de viabilidade técnica, econômica, ambiental e mercadológica da instalação original de fábrica de sistema de conversão para uso de gás natural em veículos leves movidos a gasolina e/ou álcool. / Technical, economical, environmental and merchandizing practicability analysis of original assemblers installation of conversion system to the use of compressed natural gas in gasohol and / or ethanol impelled light vehicles.

Valiante, Daniel 14 November 2006 (has links)
É cada vez maior a busca por fontes de energia alternativas com vistas à substituição dos derivados do Petróleo, em especial após a crise da década de 70. A indústria automotiva segue a mesma tendência, buscando alternativas viáveis frente à incerteza do tempo e quantidade que ainda resta de estoque de combustíveis fósseis líquidos. Além do Álcool como meio de substituição ao Diesel e a Gasolina, a utilização de GNV - Gás Natural Veicular - está entre as tecnologias atualmente consideradas viáveis e eficientes. Segundo a ANP - Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (2006), o Brasil possui reservas comprovadas de 306,4 x 109 m3 de Gás Natural, quantidade estimada para abastecer o mercado nacional, no cenário mais pessimista, pelos próximos cinqüenta anos. A associação desses fatores resulta na busca do consumidor brasileiro pela redução dos gastos cada vez maiores com combustível e no aumento da demanda por veículos movidos a Gás Natural. Apesar da notória demanda de mercado, atualmente existem no Brasil poucas opções de veículos leves com Sistemas de Conversão originalmente instalados pelas montadoras e com manutenção da garantia de fábrica. A falta de opções de oferta abre espaço para o grande aumento do número de oficinas de conversão, freqüentemente ignorando aspectos técnicos e de legislação de conversão, na intenção de apenas obterem lucros com o aumento de demanda. Mais do que pretensiosas conclusões definitivas, o presente trabalho tem como objetivo oferecer uma pequena contribuição à indústria e à sociedade, através da análise da viabilidade técnica, econômica, ambiental e mercadológica da instalação original de fábrica de Sistema de Conversão para uso de Gás Natural em veículos leves movidos a Gasolina e / ou Álcool, frente ao atual mercado de veículos convertidos e ao aumento da demanda por fontes de energia alternativa. / The search for alternative energy sources aiming the substitution of derivate Oil products is each time higher, especially after the 70s Petroleum crisis. The automotive industry follows this trend too, looking for possible alternatives in face of the uncertainness of time and quantity available stocks of liquid fossil fuels. Besides the Ethanol as a way of Gasohol and Diesel substitution, the CNG - Compressed Natural Gas - use is nowadays considered one of the most possible and efficient technologies. According to the ANP - National Petroleum, Natural Gas and Biofuel Agency (2006), Brazil owns 306,4 x 109 m3 of Compressed Natural Gas proved reserves, which are considered enough to supply the national market, in the worst case, for the next fifty years. The conjunction of these issues results in the Brazilian customers search for the each higher fuel expenses reduction and the raise of Compressed Natural Gas impelled vehicles demand. Despite the notorious market demand, there are nowadays on Brazil only a few options of light vehicles with Conversion System originally installed by automotive assemblers and warrantys maintenance. This lack of supply options creates a large field to the raise in the quantity of conversion workshops, frequently ignoring the technical aspects and the conversion legislation only with intent of achieving profit with the demand raise. More than pretentious definitive conclusions, the present work aims to offer a small contribution to the industry and society through the technical, economical, environmental and merchandizing practicability analysis of original assemblers installation of Conversion System to the use of Compressed Natural Gas in Gasohol and / or Ethanol impelled light vehicles, in face of the actual converted vehicles market and the demand raise for alternative energy sources.
75

Análise de viabilidade técnica, econômica, ambiental e mercadológica da instalação original de fábrica de sistema de conversão para uso de gás natural em veículos leves movidos a gasolina e/ou álcool. / Technical, economical, environmental and merchandizing practicability analysis of original assemblers installation of conversion system to the use of compressed natural gas in gasohol and / or ethanol impelled light vehicles.

Daniel Valiante 14 November 2006 (has links)
É cada vez maior a busca por fontes de energia alternativas com vistas à substituição dos derivados do Petróleo, em especial após a crise da década de 70. A indústria automotiva segue a mesma tendência, buscando alternativas viáveis frente à incerteza do tempo e quantidade que ainda resta de estoque de combustíveis fósseis líquidos. Além do Álcool como meio de substituição ao Diesel e a Gasolina, a utilização de GNV - Gás Natural Veicular - está entre as tecnologias atualmente consideradas viáveis e eficientes. Segundo a ANP - Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (2006), o Brasil possui reservas comprovadas de 306,4 x 109 m3 de Gás Natural, quantidade estimada para abastecer o mercado nacional, no cenário mais pessimista, pelos próximos cinqüenta anos. A associação desses fatores resulta na busca do consumidor brasileiro pela redução dos gastos cada vez maiores com combustível e no aumento da demanda por veículos movidos a Gás Natural. Apesar da notória demanda de mercado, atualmente existem no Brasil poucas opções de veículos leves com Sistemas de Conversão originalmente instalados pelas montadoras e com manutenção da garantia de fábrica. A falta de opções de oferta abre espaço para o grande aumento do número de oficinas de conversão, freqüentemente ignorando aspectos técnicos e de legislação de conversão, na intenção de apenas obterem lucros com o aumento de demanda. Mais do que pretensiosas conclusões definitivas, o presente trabalho tem como objetivo oferecer uma pequena contribuição à indústria e à sociedade, através da análise da viabilidade técnica, econômica, ambiental e mercadológica da instalação original de fábrica de Sistema de Conversão para uso de Gás Natural em veículos leves movidos a Gasolina e / ou Álcool, frente ao atual mercado de veículos convertidos e ao aumento da demanda por fontes de energia alternativa. / The search for alternative energy sources aiming the substitution of derivate Oil products is each time higher, especially after the 70s Petroleum crisis. The automotive industry follows this trend too, looking for possible alternatives in face of the uncertainness of time and quantity available stocks of liquid fossil fuels. Besides the Ethanol as a way of Gasohol and Diesel substitution, the CNG - Compressed Natural Gas - use is nowadays considered one of the most possible and efficient technologies. According to the ANP - National Petroleum, Natural Gas and Biofuel Agency (2006), Brazil owns 306,4 x 109 m3 of Compressed Natural Gas proved reserves, which are considered enough to supply the national market, in the worst case, for the next fifty years. The conjunction of these issues results in the Brazilian customers search for the each higher fuel expenses reduction and the raise of Compressed Natural Gas impelled vehicles demand. Despite the notorious market demand, there are nowadays on Brazil only a few options of light vehicles with Conversion System originally installed by automotive assemblers and warrantys maintenance. This lack of supply options creates a large field to the raise in the quantity of conversion workshops, frequently ignoring the technical aspects and the conversion legislation only with intent of achieving profit with the demand raise. More than pretentious definitive conclusions, the present work aims to offer a small contribution to the industry and society through the technical, economical, environmental and merchandizing practicability analysis of original assemblers installation of Conversion System to the use of Compressed Natural Gas in Gasohol and / or Ethanol impelled light vehicles, in face of the actual converted vehicles market and the demand raise for alternative energy sources.
76

Trace Elemental Analysis of Ashes in the Combustion of the Binder Enhanced d-RDF by Inductively Coupled Plasma Atomic Emission Spectroscopy

Tai, Chia-Hui 11 1900 (has links)
Incineration is an attractive solution to the problems of disposing of municipal solid wastes and supplying energy. Because up to 25 percent of the waste in refuse-derived-fuel systems is ash, the physical and chemical characteristics of ash become more and more important for its potential impacts and methods suitable for their disposal. Trace elements concentration in ash is of great interest because of its relationship to regulatory criteria under the Resource Conservation and Recovery Act (RCRA) regarding toxicity and hazards. The applications of a microwave oven sample dissolution method has been tested on a variety of standard reference materials, with reproducible and accurate results. Fourteen trace elements, As, Ba, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se, Tl, V, and Zn, from the dissolved ash samples were determined by inductively coupled plasma atomic emission spectrometry.
77

Možnosti využití LNG v ČR / Possible Applications of LNG in the Czech Republic

Machalová, Markéta January 2013 (has links)
This thesis evaluates the possibilities of application of LNG (liquefied natural gas) in the Czech Republic. LNG is a relatively new commodity, which has broad use in the world, but as of now, the Czech Republic hasn't entered its market. The main objective of this thesis is to determine whether there exists suitable use for LNG in the Czech Republic today. By analysis and calculation I came to the conclusion, that there are applications that would be economically advantageous and would, in addition, bring other significant benefits, such as reducing emissions. The most perspective is the use of LNG as an alternative truck fuel. Under certain conditions suitable applications are also LNG satellite stations, cogeneration or bus transport. The conclusion of this thesis is that liquefied natural gas has a great potential to expand to the Czech Republic.
78

Evaluating the Economic Feasibility of Canola Biodiesel Production in North Dakota

Tapasvi, Dhruv, 1981- January 2006 (has links)
Numerous factors have pushed energy from biomass to the forefront of policy and industry discussions. Large harvests of traditional crops, low farm prices, dependence on foreign energy sources, and environmental problems have increased interest in renewable energy sources. Tools are needed to evaluate and compare different available feedstocks and to identify parameters and modifications for the production of renewable fuels such as biodiesel. The first paper examines the development of a biodiesel process model using commonly available spreadsheet software and process-engineering principles. The basis of the model is a continuous process with two stirred-tank reactors and sodium methoxide catalysis. The process is modeled as 27 units with 51 flows and 18 components. Mass flow rates and compositions of the process input and output streams are quantified using mass and component balances, energy balances, stoichiometric relations, and established process parameters. Oil composition and rate, methanol:triglyceride ratio, and expected transesterification of triglyceride are the user-specified inputs in the model. Based on commonly reported parameters (6: 1 methanol:triglyceride ratio and 98% transesterification) and a basis of 100 kg/h crude soybean oil, the model computes inputs of 13.8, 10.8, and 34.7 (in kg/h) for methanol, 10% sodium methoxide in methanol, and process water, respectively; and outputs of 93.5, 10.3, and 55.6 for soy biodiesel, glycerol, and waste stream, respectively. In the second paper, the mass flow rate data from the developed biodiesel process model are linked to cost data for evaluating the economic feasibility of biodiesel production in North Dakota with canola oil as the feedstock. Estimations of capital investment cost and total annual biodiesel product cost are conducted for two canola biodiesel production plants with 5 and 30 million gallons per year (MGY) capacities. These capacities were selected based on North Dakota and neighboring states' biodiesel demands, respectively. Capital investment cost analysis shows the presence of considerable economies of scale for the biodiesel production process for the two capacities. These cost calculations are based on the purchased equipment cost calculated from the equipment specifications. Total annual biodiesel product cost analysis shows that the major portion (>80%) of the total product cost is the raw material cost, similar to the analysis of previous economic feasibility studies. Cost benefits from the economies of scale are still present for the fixed charges, general expenses, and the manufacturing costs (other than the raw material costs) in the annual product cost calculations for the two production plant capacities. Finally, based on the gross profit evaluation for both plants, this study concludes that it is more worthwhile to invest in the 30 MGY production plant because of the greater cost returns from the economies of scale benefits. The results are more encouraging after the incorporation of the federal biodiesel tax incentive and favor the investment for biodiesel production in North Dakota. / North Dakota. Agricultural Experiment Station / USDA-CSREES (under Agreement No. 2003-34471-13523)
79

The Diffusion of Hydrogen Technology in the Road Transport Sector in Sweden

Bratt, Henrik January 2022 (has links)
Carbon emissions are one of the primary drivers of climate change and the transport sector accounts for 24% of the global carbon emissions. A shift within the automobile industry towards more eco-friendly modes of transportation is hence needed. Vehicles powered by hydrogen are a carbon emissions-free mode of transportation and have been identified as a viable approach to de-carbonize the transport sector, yet, the number of hydrogen-powered vehicles on the roads in Sweden as of 2022 is relatively low compared to the rest of the world. The aim of this study was both to identify factors that are important for actors to invest in hydrogen technology within the transport sector, and to identify how the collaboration between different actors was formed during the adoption process. The study uses a multiple-case study research design where the five cases of Storuman, Mariestad, Sandviken, Trelleborg and Ljungby were selected. Data was collected through eleven semi-structured interviews over video calls. The study has examined the diffusion process of hydrogen technology within the transport sector of each case according to the diffusion of innovations theory. An analysis of the diffusion of hydrogen technology has not, to the best of my knowledge, been conducted in the examined cases. Gaining an understanding of these processes can provide guidance for other municipalities or actors who aims to reduce their emissions and can play an important role in achieving Sweden´s objective of becoming the world´s first fossil-free welfare nation. The findings of the study were that investments in hydrogen technology within the transport sector are currently not economically profitable. However, investments in the innovation were still motivated in terms of a relative environmental advantage, reception of financial funding, the will to take a leading role in the energy transition, geographical location, long-term economic benefits and indirect economic benefits which mainly include that the municipality can market themselves as green and progressive in order to attract competent workforce and business opportunities. The study also concluded that local political support is an important pre-condition for a successful adoption of the innovation.
80

Alternative Drivetrain for Future Freight Trucks

Tsamos, Athanasios January 2020 (has links)
Presently, heavy-duty trucks are responsible for approximately 25% of global CO2 emissions. Although the world seems to incline towards the transport sector's electrification, the electrification of long-range freight trucks is profoundly challenging. The dominant disincentives are the required infrastructure, cost/size of batteries, limited mileage, and long charging sessions. However, despite the efforts to reduce emissions, current trends indicate that these continue to rise, mostly because of the continually increasing freight transit. Regional economies are heavily dependent on the latter. Thus, the imminent depletion of fossil fuels and the emerging environmental issues are disquieting aspects for the sustainability of this crucial sector. This thesis focuses on the possible alternative powertrain/drivetrain solutions for heavy-duty, long-range freight trucks in conjunction with sustainable energy carriers for the transportation sector overall. In terms of viable fuelling alternatives, the following are being reviewed: Electric Power, Bio-Fuels, and Synthetic Fuels, along with their current status, advantages, disadvantages and future prospects. In terms of powertrain/drivetrain alternatives, the following are being theoretically and critically evaluated and compared against a direct drive conventional Diesel engine truck (25.2% wheel efficiency): Battery Electric, Electric powered with overhead cables or underground conductive coils, combined Gas Turbine/Stirling Engine Hybrid Electric in series, combined Diesel engine/Stirling engine Hybrid Electric in series, and Diesel engine Hybrid Electric in series.  It is concluded that the best scenario for future freight trucks, is the use of an electric drivetrain/powertrain in conjunction with overhead powering cables along the highways. However, due to uncertainties in the universal realization of such infrastructure, to ensure uninterrupted transportation of goods, a plausible transitional solution could be the use of a Diesel engine/Stirling engine Hybrid Electric in series technology. This could reduce emissions/consumption by a factor of 2.4 (60% wheel efficiency). For the case of Gas turbine/Stirling engine and Diesel engine (both) Hybrid Electric in-series arrangements, this factor drops to 1.7 and 1.4 (42.9% and 34.3% wheel efficiency), respectively. Furthermore, this can be a clean and sustainable solution if biofuels are employed as the prime energy carriers. Such an approach is future-proof for use with overhead cables, since the suggested powertrain is electric, rendering a freight truck as a very versatile heavy-duty, long-range vehicle. Electro-fuels are not considered as a viable option due to their inefficient formulation, elevated costs, and problematic handling (Hydrogen).

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