Teses / dissertações: "Ecotoloxicology of alternative fuels"

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TAVARES, Maria Gizelda de Oliveira. "Análise físico-química e ecotoxicológica de combustíveis obtidos a partir do craqueamento termo-catalítico de polímeros". Universidade Federal de Goiás, 2008. http://repositorio.bc.ufg.br/tede/handle/tde/340.

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Made available in DSpace on 2014-07-29T12:05:39Z (GMT). No. of bitstreams: 1 tese_pre_text_Gizelda.pdf: 110896 bytes, checksum: 62cbe3b7eacec8f8144ccf9ac3a12bd9 (MD5) Previous issue date: 2008-03-28
The present paper describes the theoretical reference for the study of the polymeric thermal catalytic cracking. A review on these type of materials it was accomplished, beginning for an introduction on new sources of alternative energy. Recycling plastics used as alternative sources fuels was evaluated under the environmental and point of view physical -chemical..The studies permitted validate the developed methodology in the research.. Ecotoxicology was used as a fundamental tool to evaluate the toxicity levels of alternative fuels sources, and the obtained levels was compared to the thoroughly used fuels, such as diesel and gasoline. And the Histology studies generated in the ecotoxicology analyses, was used as a supporting tool to obtain the conclusions.
Essa pesquisa descreve o referencial teórico para o estudo do craqueamento termocatalítico de polímeros. Uma revisão desse tipo de material foi realizada começando com uma introdução sobre novas fontes de energias alternativas. A reciclagem dos plásticos usados como fonte alternativa de combustíveis, foi avaliada sob o ponto de vista ambiental e físico químico. O estudo permitiu validar a metodologia desenvolvida na pesquisa. A Ecotoxicologia foi usada como importante ferramenta para avaliar e comparar os níveis de toxicidade dos novos combustíveis obtidos na pesquisa, com relação aos combustíveis amplamente utilizados, tais como o diesel e a gasolina. E usou-se a Histologia como suporte de apoio aos resultados gerados nas análises ecotoxicológicas para se obter as conclusões.

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Nwafor, Onwuzurigbo Martin I. "Alternative fuels in diesel engines". Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239031.

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Bari, Saiful. "Alternative fuels in diesel engine". Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303788.

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Chong, Cheng Tung. "Combustion characteristics of alternative liquid fuels". Thesis, University of Cambridge, 2011. https://www.repository.cam.ac.uk/handle/1810/244379.

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Envisaged application of biodiesel in gas turbine engines or furnaces requires extensive tests on the deflagration properties of biodiesel. The laminar flame speeds of Palm Methyl Esters (PME) and blends of PME with conventional fuels are determined using the jet-wall stagnation flame configuration. The same technique is also used to measure the laminar flame speed of diesel, Jet-A1, n-heptane, acetone, methane and methane/acetone. The spray atomization characteristics of a plain-jet airblast atomizer are investigated using a phase Doppler anemometry (PDA) under non-reacting conditions. The droplet size and velocity distribution of biodiesels are compared to conventional fuels. For spray combustion investigations, a generic gas turbine-type combustor is developed to compare the spray flame established from PME, rapeseed methyl esters (RME), diesel, Jet-A1 and biodiesel blends. The spray droplet characteristics in the flame and the flow field in the combustor are investigated. Chemiluminescence imaging of OH* and CH* are applied to capture the global flame structure and heat release region. Flame spectroscopy and long bandpass filtered imaging at > 550 nm are performed to evaluate the tendency of soot formation. In general, biodiesels exhibit flame shapes and spray droplet characteristics that are comparable to conventional fuels. In spite of the higher fuel specific consumption, the emission of NOx is found to be lower for biodiesels compared to conventional fuels. The results show that biodiesels can potentially be used as alternative fuels for gas turbine operation.

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Kashif, Muhammad. "Measurement of sooting tendencies of alternative fuels : application to primary reference fuels". Paris 6, 2013. http://www.theses.fr/2013PA066258.

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Un dispositif a été conçu et validé pour mesurer la fraction volumique de suie dans de flammes non-prémélangées méthane/air dopées en vapeurs d’hydrocarbures liquides. La quantification en fraction volumique de suie est obtenue en inversant les données d’extinction d’un faisceau laser à travers une flamme axisymétrique par l’algorithme nommé Onion- Peeling stabilisé par une régularisation de type Tikhonov. La mesure est ensuite convertie en un indice appelé Yield Sooting Index (YSI). La méthode a été appliquée pour comparer les tendances des de mélanges de n-heptane et d’iso-octane (Primary Reference Fuels (PRFs)) à produire de suie dans une flamme non-prémélangée axisymmétrique dopée en vapeur de PRF, en maintenant constante soit la concentration en vapeur, soit de l’énergie des vapeurs injectés. Une corrélation de second ordre a été établie pour prédire la variation d’YSI avec la teneur en iso-octane dans le PRF et la concentration en dioxyde de carbone dans l’écoulement oxydant annulaire. Les études réalisées sur cette flamme de laboratoire et les résultats obtenus ont une portée pratique et doivent permettre de prédire le comportement des combustibles considérés à former de suie en condition réelles
An optical diagnostics layout is designed and validated to measure soot volume fraction in methane/air diffusion flames doped with vapors of liquid hydrocarbons. Soot volume fraction is inferred from the inversion of integrated light extinction data using an Onion-peeling algorithm stabilized by a Tikhonov regularization method. This measurement is then converted into apparatus-independent Yield Sooting Index (YSI). The method has been applied to compare the sooting tendencies of PRFs in doped axisymmetric diffusion flames when keeping the concentration or energy of injected vapors constant. A second-order correlation modeling the variation of YSI with the mole fraction of iso-octane in PRF mixture and the proportion of carbon dioxide in the co-flowing oxidizer has been established using least-squares non-linear data-fitting to experimental data. These studies performed on laboratory flames and the results obtained are of practical importance and can be used to predict the sooting behavior of fuels under practical combustion environment

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Gunnarsson, Andreas. "Analysis of Alternative Fuels in Automotive Powertrains". Thesis, Linköping University, Department of Electrical Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-17053.

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The awareness of the effect emissions have on the environment and climate has risen in the last decades. This has caused strict regulations of greenhouse gas emissions. Greenhouse gases cause global warming which may have devastating environmental effects. Most of the fuels commercially available today are fossil fuels. There are two major effects of using fuels with fossil origin; the source will eventually drain and the usage results in an increase of greenhouse gases in the atmosphere. Fuels that are created from a renewable feedstock are often referred to as alternative fuels and under ideal conditions they are greenhouse gas neutral, meaning that the same amount of greenhouse gases is released during combustion as the source of the fuel have absorbed during its growth period. This evaluation method is known as a well-to-wheel analysis which besides emissions also evaluates energy efficiencies during both the production and the combustion phases.

By evaluating results of well-to-wheel analyses along with fuel properties and engine concept characteristics, this report presents which driving scenario that is suitable for different powertrain configurations. For example, vehicles operating in high populated areas, as cities, have a driving scenario that includes low velocities and multiple stops while vehicles in low populated areas often travel long distances in higher speeds. This implies that different powertrains are suitable in different regions. By matching favorable properties of a certain powertrain to the properties important to the actual driving scenario this report evolves a fuel infrastructure that is suitable in Sweden.

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Faramarzi, Simin. "Effect of Alternative Fuels on SCR Chemistry". Thesis, KTH, Skolan för kemivetenskap (CHE), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-146185.

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In the time line of world industrial age, the most important era begins in the late 18th century when the use of fossil fuels was growing intensively. This approach has continued and developed up to the 20th century. Besides, this trend has had side effects like polluting environment. Air pollution is one of the critical issues nowadays that stems from using hydrocarbon fuels. One type of the problematic compounds in polluting air is nitrogen oxides that can be produced in combustion process from engines and industrial plants. Different solutions have been suggested to remove air polluting compounds. One method for removing nitrogen oxides is using the mechanism of Selective Catalytic Reduction in silencer of engines. This method has become practical in trucks’ engines. Therefore, research on SCR chemistry is important for improving the usage of this method in removing nitrogen oxides. SCR has its own problems when used in trucks. One of the problems is formation of white clumps on pipe wall of silencers using SCR which can cause back pressure in the engines and costs a lot to remove them from engines. This report evaluates the effect of alternative fuels on SCR chemistry .Different parameters affecting deposit formation are studied and evaluated. Ethanol is one of the controversial fuels used in engines and acetic acid is one its byproducts. Also, urea and its by products are important materials in SCR chemistry, too. Consequently, the first part of the report studies the influence of acetic acid and Ferrite steel, one of the usual steels in silencers of engines, on urea, biuret and cyanuric acid decomposition. The instruments used in the first part include TGA-DSC (Thermo Gravimetric Analysis-Differential Scanning Calorimetric) which is connected to FTIR (Fourier Transform Infrared Spectroscopy).In the second part of the report, the effect of diesel exhaust and ethanol exhaust on cyanuric acid evaporation rate is evaluated. Cyanuric acid is the main compound forming deposit in silencers. The instrument used in the second part is TGA. The third part consists surveying effect of Adblue, aqueous solution of urea, and additivised Adblue, surfactant added Adblue to improve its efficiency, in a patented rig that is scaled down of a silencer of truck. The most important result for the first part includes the effect of Ferrite steel treated with acetic acid that accelerated the decomposition of cyanuric acid. This result can be investigated more in order to be used in silencers to accelerate the decomposition rate of clumps formed. In the second part, it is found out that cyanuric acid evaporates faster under ethanol exhaust than diesel exhaust. The third part’s results shows that in the current assembly of pipes in the rig, Additivised Adblue loses its improved efficiency which is an interesting result for engine welding in order to avoid this type of connection in engines.

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Baslamisli, Ufuk. "Helicopter Turboshaft Engine Ground Preformance With Alternative Fuels". Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614098/index.pdf.

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In recent years, extensive studies on alternative fuels have been conducted to find environmentally friendly, economically feasible fuels due to finite petroleum sources, environmental and economical reasons. In this thesis, effects of alternative fuels on engine performance and exhaust emission are studied experimentally. Cold and reacting tests have been performed. Volumetric flow rate, discharge pressure are measured according to different pump speed. Droplet diameters, droplet distribution, spray cone angle and two dimensional velocity distribution from combustor fuel nozzle are determined by IPI and PIV technique. The comparative performance of alternative fuels and JET A-1 are investigated by atmospheric combustion tests and experimental turbojet tests in terms of exhaust gas temperatures, emissions, combustion chamber efficiency. Emissions, combustion chamber exit temperature profile, power turbine inlet and exhaust gas temperatures, effects of fuels on engine performance are observed and measured in detail at RR Allison 250 C-18 turbo-shaft engine.

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Rukowicz, Stefan Frederick. "Comparative analysis of alternative fuels for bus transit". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 1.04 Mb., 208 p, 2006. http://proquest.umi.com/pqdlink?did=1163250441&Fmt=7&clientId=8331&RQT=309&VName=PQD.

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Giles, Anthony Peter. "Alternative fuels and technology for internal combustion engines". Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/56090/.

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Within this thesis is an investigation and appraisal of alternative automotive fuels, internal combustion engine technology and emission reduction techniques. A review of the developments in engine technology, with specific focus on improvements in engine efficiency and emission reductions was undertaken. Tighter emission legislation imposed after the Kyoto agreement has resulted in technological advances in the field of internal combustion engines improving the economy of modern motor vehicles while reducing their emissions of C02 and particulate matter. As part of an EU funded project entitled "Magnetic Movement Valve for Miller Cycle operation of engines", the application of a novel secondary valve apparatus to an internal combustion engine was investigated through the use of computer modelling. It was shown that the secondary valve concept is capable of controlling the output of an internal combustion engine, while increasing the operating efficiency and reducing the emission of NOx through the use of Miller cycle operation and throttle free load control. A development programme of the engine and the secondary valve apparatus, carried out in conjunction with EU project partners, resulted in a marketable engine incorporating the new technology which is now in production within Europe and the Far East. An engine test-bed facility was commissioned to investigate the emissions and performance of a diesel engine fuelled by a variety of biodiesel / diesel fuel blends. It was found that incremental addition of biodiesel to a low sulphur diesel fuel resulted in a decrease in engine power and an increase in fuel consumption, CO2 and NOx emissions. The particulates levels of pure biodiesel emissions were found to be much lower (by mass and number concentration) than that of the low sulphur diesel fuel. From analysis of the exhaust gases it was found that the average size of the particulates is larger for biodiesel fuel than for the low sulphur diesel fuel.

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Catalanotti, Elena. "Theoretical and experimental investigation of alternative aviation fuels". Thesis, University of Leeds, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.550587.

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Problems related to security of supply and environmental issues have led the research to find and investigate the possibility for short and long term replacement of conventional petrochemical fuels. In the aviation industry two alternatives have been indicated as possible substitutes to pure kerosene based fuels: blends of kerosene and biodiesel as well as blends of kerosene and Fischer- Tropsch synthetic fuels. Chemical kinetic studies have widely investigated the performance of pure kerosene, pure methyl esters as surrogates of biodiesel, as well as of mixtures of kerosene and biodiesel. A comprehensive theoretical model for the oxidation of blends of kerosene, biofuels and synthetic fuels is proposed in this work, the biofuel portion being represented for the first time by methyl tridecanoate (MTD), a methyl ester with a carbon chain of 13 carbon atoms and chemical formula C14H2802, the synthetic fraction by heptanes. Therefore this work has produced a novel and an original mechanism containing fuels of different characteristics combined in a single scheme and provides a chemical kinetic mechanism for a large methyl ester not previously reported in the current literature. The model development has undergone through the preliminary construction of a reaction mechanism including kerosene and methyl butanoate (MB), the AFRM v2.0 (Aviation Fuel Reaction Mechanism version 2.0). AFRM v2.0 has been updated through a multi-parameter optimization, including the addition of the reactions for the breakdown of the C-14 methyl ester and a set of reactions for the oxidation of heptane. The final scheme consists of surrogate kerosene components n-decane and toluene, a surrogate FAME (methyl tridecanoate), and a surrogate of the synthetic paraffinic portion, heptane. The scheme also includes NOx, SOx and PAH chemistry. Perfectly Stirred Reactor simulations were compared to experimental results from Dagaut et al. for the oxidation of bio-kerosene and pure heptane in a Jet Stirred reactor at different fueV02 equivalence ratios. To investigate the combustion behaviour of the alternative aviation fuels in a flat premixed flame, an experimental study at a variety of stoichiometries of kerosene, kerosenelbiofuel blends, and Fischer- Tropsch derived kerosene substitutes have been performed. A fine wire thermocouple measures the temperature profile of the flame, and product analysis by online gas sampling provides the major species concentrations (02, CO2, CO) along with NOx. These measurements are complemented by the use of a Planar Laser Induced Fluorescence (PLIF) to provide relative concentration profiles of NO and the reactive intermediate OH.

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Zhang, Taoju. "Possibilities of Alternative Vehicle Fuels : a literature review". Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-19896.

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Historically, gasoline and diesel have been used as vehicle fuels for a long time. But the decline of oil supply and unstable oil price drive people to find alternative energy for vehicle fuel. Alternative energy solutions may shift energy consumption to less carbon, less pollutions and provide more energy diversity. These issues are investigated in the present literature review. The first part of the thesis introduces different kinds of alternative energy for vehicles, such as biofuel, natural gas, hydrogen, liquefied petrol gas, electricity and compressed air. The presentations includes their utilization, production, environment effect, running performance, fuel property, market share, running and investigate cost and production barriers. The second part of the thesis work compares the properties of the alternative fuels and discusses the advantages and drawbacks of different types of fuel energies. Compared with traditional fuels, alternative fuels have superiority in environment impact, sustainability and energy efficiency. Some of them have been used in reality and show a potential as future fuels. The author found that natural gas and liquefied petrol gas have low running costs, better environment performance and acceptable running range, and thus are able to substitute conventional fuels in the short term. Biofuel has better sustainability than gasoline. It will probably become more sustainable and cost effective in the mid-term period. Electricity can also become a future fuel in mid-term period since it has excellent emission performance and low running costs. Hydrogen is expected to substitute conversional fuels in the long term due to high investment costs and current unsustainable production pathway of the latter. The compressed air turned out not suitable for substituting conventional fuels because of poor efficiency and running range performance.

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Withers, Mitch Russell. "Environmental and economic assessment of alternative transportation fuels". Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/90808.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 56-63).
Alternative fuels have the potential to mitigate transportation's impact on the environment and enhance energy security. In this work, we investigate two alternative fuels: liquefied natural gas (LNG) as an aviation fuel, and middle distillate fuel derived from woody biomass for use in aviation or road transport. The use of LNG as a supplemental aircraft fuel is considered in the context of the Lockheed Martin C- 1 30H and C-130J transport aircraft. We estimate the cost of retrofitting these aircraft to use LNG and the savings from reduced fuel expenses. We evaluate the societal impacts of LNG within a cost-benefit framework, taking into account resource consumption, human health impacts related to air quality, and climate damage. We find that aircraft operators can save up to 14% on fuel expenses (retrofit costs included) by employing LNG retrofits, with a 95% confidence interval of 2-23%. Society can also benefit by 12% (3-20%) from LNG use as a result of improved surface air quality, lower resource consumption, and climate neutrality relative to conventional fuel. These results are highly dependent on fuel prices, the quantity and cost of the LNG retrofits, and the frequency and length of missions. Woody biomass harvested from old-growth forests produces a large carbon debt when used as a feedstock for transportation fuel. Managed forests are an attractive alternative for inexpensive biomass production with the potential to reduce this carbon debt. We study the effect of forest management practices on the carbon debt payback time resulting from harvesting woody biomass from managed forests for middle distillate fuel production. We also calculate the breakeven time in terms of radiative forcing, temperature change, and economic damages. We find that biofuels produced over a period of 30 years have higher CO 2 emissions than fossil fuels for 59 years, higher radiative forcing for 42 years, higher temperature change for 48 years, and higher cumulative discounted (1-2%) economic damages for more than 100 years. These damages never break even at discount rates above 2%. Payback times can be reduced by increasing the age at which biomass is harvested. When biofuel production is sustained indefinitely, greater climate benefits are achieved over the next 100 years by instead producing long-lived wood products like lumber.
by Mitch Russell Withers.
S.M.

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Foscoli, Beatrice. "Alternative fuels for shipping : Feasibility study in Singapore". Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279509.

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This thesis work was performed as a collaboration between the University of Cambridge and the Royal Institute of Technology and was initially intended to be performed as a 5-months internship at the CREATE Centre of Singapore. Unfortunately, due to the COVID-19 pandemic, it could only be done remotely. The aim of the research is to investigate the use of alternative fuels for shipping in Singapore, as maritime power in a global process of decarbonization of this sector. A range of alternative fuels and technologies with different carbon reduction potentials, depending on the primary energy source, have been proposed for ships to reduce emissions. The overall ambition of the project has been to carry out a comprehensive study, based on existing academic and industry literature, on the technical viability of alternative marine fuels tailored to the context of Singapore. The approach of the study has been to assess how a selection of alternative fuels performs on a set of parameters. The alternative fuels included are hydrogen (H2), ammonia (NH3), methanol (MeOH1 ), biodiesel (FAME) and liquefied natural gas (LNG). LNG offers a good compromise between energy consumption for its production and reduction of emissions but will not be able to meet carbon coals in the long term. Bio-MeOH from woody biomass finds large applicability in Singapore given the abundance of feedstock in the South East Asian region and can deliver relevant CO2 emissions reduction. However, as for biodiesel, sustainability and availability concerns might rise questions on its impact as viable long-term solution. E-fuels, under renewable resources production, can deliver significant environmental benefits but at the moment seem to be inaccessible to Singapore considering the amount of clean electricity needed for their production. Results show that the main challenge for Singapore towards the decarbonization of shipping is the procurement of primary resources. Ensuring energy security in a sustainable way in a postpandemic context like South East Asia, where the priority for the coming 30 years will be an unprecedented economic boom, will first and foremost see Singapore engaged in international policies and collaboration in support of emerging economies.
Detta avhandlingsarbete utfördes som ett samarbete mellan University of Cambridge och Kungliga Tekniska Högskolan och var ursprungligen avsett att utföras som en 5-månaders praktik vid CREATE Center i Singapore. Tyvärr, på grund av COVID-19-pandemin, kunde det bara göras på distans. Syftet med forskningen är att undersöka användningen av alternativa bränslen för sjöfart i Singapore som maritim kraft i en global process för avkarbonisering av denna sektor. Ett antal alternativa bränslen och tekniker med olika koldioxidreduktionspotentialer, beroende på den primära energikällan, har föreslagits för fartyg för att minska utsläppen. Projektets övergripande ambition har varit att genomföra en omfattande studie, baserad på befintlig akademisk och industriell litteratur, med den tekniska tillgängligheten av alternativa marina bränslen anpassade till Singapore. Studiens tillvägagångssätt har varit att bedöma hur ett urval av alternativa bränslen presterar på en uppsättning av parametrar. De alternativa bränslena som ingår är väte (H2), ammoniak (NH3), metanol (MeOH), biodiesel (FAME) och flytande naturgas (LNG). LNG erbjuder en bra kompromiss mellan energiförbrukning för sin produktion och minskning av utsläpp men kommer inte att kunna möta fossilt kol på lång sikt. Bio-MeOH från ved-biomassa finner stor tillämpbarhet i Singapore med tanke på överflödet av råmaterial i Sydostasien och kan ge relevant CO2-utsläppsminskning. Vad gäller biodiesel kan emellertid problem med hållbarhet och tillgänglighet väcka frågor om dess inverkan som en långsiktig lösning. E-bränslen, under produktion av förnybara resurser, kan ge betydande miljöfördelar men verkar för tillfället vara otillgängliga för Singapore med tanke på hur mycket ren el som behövs för deras produktion. Resultaten visar att den största utmaningen för Singapore mot avkarbonisering av sjöfarten är upphandling av primära resurser. Att säkerställa energisäkerhet på ett hållbart sätt i ett postpandemiskt sammanhang som Sydostasien, där prioriteringen under de kommande 30 åren kommer att vara en oöverträffad ekonomisk boom, kommer först och främst se Singapore engagerade i internationell politik och samarbete till stöd för tillväxtekonomier.

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Liu, Yue. "Investigation on elastomer compatibility with alternative aviation fuels". Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/4829/.

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The introduction of synthetic fuels produced from various alternative approaches has led to the concern over their compatibility with elastomeric seals used in current aircraft engines. The aim of this research is to investigate into this compatibility issue of alternative aviation fuels with typical elastomeric sealing materials. Experimental methodologies employed were the stress relaxation test (under both isothermal and temperature cycling conditions) and the Fourier Transform Infrared (FTIR) spectroscopy. A wide range of valuable data was collected and detailed analysis was carried out using statistical method and the Hansen Solubility Parameters (HSPs). The outcome of this research establishes the fundamental stress relaxation characteristics of typical sealing materials in jet fuels produced via various sources. It demonstrates different impacts that individual fuel species may have on seals. A correlation has been found between the stress relaxation and the molecular structure changes of the O-rings. The HSP analysis suggests a good non-linear correlation between the equilibrium compression force and the RED number generated from the ‘triangle’ test data. It is proved that temperature is an influential factor in terms of the sealing performance of an O-ring. Generally, the stress relaxation process slows down (accelerates) as the temperature decreases (increases). At extremely low temperatures, seals become very inert and the relaxation process would stop. Temperature cycling tests show the relationship between seals’ ability to recovery from thermal contraction and the aromatic content in the fuel. Based on the knowledge gained here, recommendations have been given on the potential future work related to this topic.

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Akkapeddi, Srikanth Schindler Anton K. "Alternative solid fuels for the production of Portland cement". Auburn, Ala., 2008. http://hdl.handle.net/10415/1432.

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Shasby, Benjamin Matthew. "Alternative Fuels: Incompletely Addressing the Problems of the Automobile". Virginia Tech, 2004. http://hdl.handle.net/10919/9976.

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The inordinate reliance of the United States on the automobile for transportation causes a number of problems for the nation. Finite supplies of petroleum imported from volatile parts of the world place the economy at risk from price spikes and eventual depletion. Pollution from motor vehicle exhaust has public health and environmental consequences. Many politicians, automotive interest groups, and others advocate for the use of alternative fuels to replace fossil fuels. This paper investigates the advantages and disadvantages of the following: Natural Gas, Ethanol, Biodiesel, Hydrogen Fuel Cells, and Hybrid Gasoline Electric Systems. The paper concludes with a discussion of the problems associated with the automobile that will not be addressed through a movement towards alternative fuels: urban sprawl, transportation equity, environmental degradation, and public health.
Master of Urban and Regional Planning

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Altaher, Mohamed Alalim. "Combustion and emissions of alternative fuels in gas turbines". Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/4954/.

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Renewable biomass derived fuels are of increasing interest for many applications including industrial and aero gas turbines due to the reduction in fossil fuel CO2 and the improvement in energy supply security. The first part of this work investigated the performance of biodiesel as a fuel in low NOx combustors of the type used in industrial gas turbines. This work included comparison with kerosene and co-firing with natural gas and blends of kerosene/biodiesel. In the second phase of this work an aircraft gas turbine APU with diffusion combustion. This investigated the gaseous and particulate emissions using kerosene as a base fuel for comparison with several second generation biofuels, which covered a range of H/C and showed that emissions were correlated with the H/C. The third phase of the work was concerned with renewable or clean coal derived hydrogen combustion using a low NOx flame stabilizer for industrial power generation applications. For the industrial low NOx combustor work a radial swirler flame stabiliser was used. However, the high boiling point of B100 made operation in a premixed vane passage fuel injection mode impossible as ignition could not be achieved. The pilot fuel injector in the centre was the only fuel injection location that B100 would stabilise a flame, due to the central recirculation of burnt gases. A central 8 hole radially outward fuel injector was used as WME (B100) would not operate with radial vane passage fuel injection that is conventionally used for low NOx radial swirlers with natural gas. In the aero engine phase of the research, nine alternative fuels were tested and compared to conventional JetA1 fuel at idle and full power. The results showed that all fuels produced similar level of NOx compared to JetA1 and a slight reduction in CO. A remarkable reduction in UHC was observed at all conditions for higher H/C fuels. The results also show that there was a good correlation between fuels H/C ratio and particle concentrations, particle size and distributions characteristics. The hot idle produced ~20% less particles compare to the cold idle. The alternative fuel blends produced fewer particles than JetA1 fuel. The alternative source of renewable fuels for industrial power generation gas turbines is that of hydrogen derived from renewable or nuclear electricity or from coal or biomass gasification using the water gas shift reaction and CO2 solvent extraction to leave a pure hydrogen fuel. The key problem are in burning hydrogen in gas turbines is that of the increased NOx formation and the increased risk of flashback into the conventional premixing passages used in natural gas low NOx combustors. This work investigated a novel impinging jet configuration that had previously been used successfully with propane and kerosene fuels. It had no premixing so that there could be no flashback. However, the high reactivity of hydrogen did cause a problem with flame stabilization too close to the jet outlets. This was controlled by reducing the proportion of air added to the initial hydrogen jets. NOx emissions lower than alternative designs were demonstrated at simulated high power conditions. This was a practical combustion technique for high hydrogen content fuels with low NOx emissions and no flashback problems.

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Gül, Timur. "An energy-economic scenario analysis of alternative fuels for transport /". Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17888.

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Hui, Lai-yee, e 許麗儀. "Alternative fuels and reduction of air pollution in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31254883.

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Hui, Lai-yee. "Alternative fuels and reduction of air pollution in Hong Kong /". Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B23424916.

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Harrison, William E. (William Elton). "Alternative fuels : how can aviation cross the "Valley of Death"". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44433.

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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management, 2008.
Leaf 260 blank.
Includes bibliographical references.
Aviation has used petroleum-derived fuels for over 100 years. With the rapidly rising price of oil and concerns about supply, the military and the commercial airlines are fostering the development of an alternative aviation fuel industry. In the U.S., coal, oil shale and biomass offer great promise as alternatives to petroleum for the production of aviation fuels. For the alternative fuel to be viable, the fuel must be price competitive, offer environmental benefits compared to petroleum, and must be qualified and certified for use in aviation. This thesis explores the barriers and risks associated with the technology adoption life cycle for alternative aviation fuels as viewed through the lenses of the technology developer, the early adopter, the early majority user, and the financial community. The challenges related to crossing the "Valley of Death" between technology development and deployment, and bridging the "Chasm" between the early adopters and the early majority of users are explored and a series of evaluation frameworks, tools, models, and recommendations are presented. The suggestions and recommendations provide potential actions that the military and the civil aviation sector could implement to reduce the risks and barriers for an alternative aviation fuel industry to commence and be sustainable both financially and environmentally.
by William E. Harrison, III.
M.B.A.

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23

Mbarawa, M. "Performance, emission and economic assessment of clove stem oil–diesel blended fuels as alternative fuels for diesel engines". Elsevier, 2007. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000685.

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In this study the performance, emission and economic evaluation of using the clove stem oil (CSO)–diesel blended fuels as alternative fuels for diesel engine have been carried out. Experiments were performed to evaluate the impact of the CSO–diesel blended fuels on the engine performance and emissions. The societal life cycle cost (LCC) was chosen as an important indicator for comparing alternative fuel operating modes. The LCC using the pure diesel fuel, 25% CSO and 50% CSO–diesel blended fuels in diesel engine are analysed. These costs include the vehicle first cost, fuel cost and exhaust emissions cost. A complete macroeconomic assessment of the effect of introducing the CSO–diesel blended fuels to the diesel engine is not included in the study. Engine tests show that performance parameters of the CSO–diesel blended fuels do not differ greatly from those of the pure diesel fuel. Slight power losses, combined with an increase in fuel consumption, were experienced with the CSO–diesel blended fuels. This is due to the low heating value of the CSO–diesel blended fuels. Emissions of CO and HC are low for the CSO–diesel blended fuels. NOx emissions were increased remarkably when the engine was fuelled with the 50% CSO–diesel blended fuel operation mode. A remarkable reduction in the exhaust smoke emissions can be achieved when operating on the CSO–diesel blended fuels. Based on the LCC analysis, the CSO–diesel blended fuels would not be competitive with the pure diesel fuel, even though the environmental impact of emission is valued monetarily. This is due to the high price of the CSO.

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24

Swart, Dustin W. "The utilization of alternative fuels in the production of Portland cement". Auburn, Ala., 2007. http://repo.lib.auburn.edu/07M%20Theses/SWART_DUSTIN_26.pdf.

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Waters, Heather. "Converting Sweet Sorghum to Ethanol - An Alternative Feedstock for Renewable Fuels". Thesis, The University of Arizona, 2012. http://hdl.handle.net/10150/271930.

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The goal of this project was to design an ethanol production process from sweet sorghum for use as a renewable fuel. Sorghum stalks are first harvested and sent through a series of 2 three-roller extractors (70% total efficiency). Extracted juice is pumped to the reactor for preservation and fermentation. Sodium metabisulfite preserves the juice. Ethanol Red (Saccharomyces cerevisiae) is the fermentation yeast. Following fermentation, the juice (8% ethanol by mass) is distilled to achieve 90% ethanol. A molecular sieve extracts excess water, resulting in 100% ethanol. Plant wastes accumulate during the process. These wastes are collected, dried, and sold as animal feed for profit. The project economics indicate that the overall process is not currently economically feasible. The net present value (NPV) for the optimum economic situation, assuming a 15 year plant lifetime and 15% interest rate, is -$125 M. Under these circumstances, the ethanol would need to be sold at $44.37 per gallon to break even. To improve this process, further development of methods for increasing juice extraction efficiency should be explored. Additionally, the distillation process could be enhanced with a second distillation column to achieve 95% ethanol prior to using the molecular sieve.

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Ng, Bing Benson, e 吳賓. "Cleaner alternative fuels for vehicles: a cleaner future for Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31255036.

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Rydalch, Andrew J. "Ignition delay properties of alternative fuels with Navy-relevant diesel injectors". Thesis, Monterey, California: Naval Postgraduate School, 2014. http://hdl.handle.net/10945/42715.

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Approved for public release; distribution is unlimited
In support of the Navy’s Green Fleet Initiative, this thesis researched the ignition characteristics for diesel replacement fuels used with Navy-relevant fuel injectors. A constant-volume combustion chamber was used to simulate Top-Dead-Center conditions of a diesel engine using an ethylene-air preburn with appropriate make-up oxygen. The injection conditions ranged from temperatures of 1,000 K to 1,300 K and densities has high as 14.8 kg/m3. Hydrotreated renewable diesel (HRD) and direct sugar-to-hydrocarbon (DSH) fuels were injected into the combustion chamber using a Sturman research injector, a Yanmar injector, and an Electro Motive Diesel (EMD) injector. The primary means of data collection was optical emission imaging of laser induced fluorescence of the fuel and broadband emission of the combustion event. The ignition delay was determined using high speed imaging at 50 kHz to determine the time delay between start of injection and start of combustion. The results of the study show that the ignition delay characteristics for the F-76/HRD 50/50 blend are compatible with those of conventional F-76 diesel fuel for both the Yanmar and EMD injectors at the conditions tested. The ignition delay characteristics of the F-76/DSH 50/50 blend fuel for the Yanmar injector were also compatible with those of F-76.

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Ng, Bing Benson. "Cleaner alternative fuels for vehicles a cleaner future for Hong Kong /". Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B23426044.

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Wong, Hsin Min. "Life-cycle assessment of Greenhouse Gas emissions from alternative jet fuels". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/50611.

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Thesis (S.M. in Technology and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2008.
Includes bibliographical references (p. 137-147).
The key motivation for this work was the potential impact of alternative jet fuel use on emissions that contribute to global climate change. This work focused on one specific aspect in examining the feasibility of using alternative jet fuels - their life-cycle Greenhouse Gas (GHG) emissions relative to conventional jet fuel. This involved the quantification of the overall GHG emissions of potential alternative jet fuels, from feedstock recovery and transportation, to the production, transportation and utilization of the fuels. The fuels examined in this work included jet fuel and ultra-low sulfur jet fuel from conventional crude, jet fuel from oil sands and oil shale, Fischer-Tropsch jet fuel from natural gas, coal and biomass, and biojet from soy oil and palm oil. By identifying and varying important input parameters, a range of life-cycle GHG emissions for each fuel pathway was derived. From the analyses in this work, only alternative jet fuels from biomass offer substantial life-cycle GHG emissions reductions compared to conventional jet fuel, and that is true only if land use change emissions were negligible. Direct or indirect land use changes from the use of biomass feedstocks (particularly food crops) could potentially increase life-cycle GHG emissions to levels several times above that of conventional jet fuel. A scenario analysis was conducted to examine the amount of biofuel needed to displace conventional jet fuel in 2025 to maintain U.S. aviation GHG emissions at baseline 2006 levels. It was found that the large-scale deployment of biofuels to achieve carbon-neutral U.S. aviation growth through 2025 was limited by feedstock and land availability if current generation biofuels (particularly those made from food crops) were used. Hence, it is important to explore the use of next generation non-food, high yield feedstocks (e.g. algae) that use little land and result in little or no land use change emissions for large-scale biofuel production.
by Hsin Min Wong.
S.M.in Technology and Policy

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30

Hui, Xin. "Flame Studies on Conventional, Alternative, and Surrogate Jet Fuels, and Their Reference Hydrocarbons". Case Western Reserve University School of Graduate Studies / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=case1354909906.

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Tsamos, Athanasios. "Alternative Drivetrain for Future Freight Trucks". Thesis, Högskolan i Gävle, Energisystem och byggnadsteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-33395.

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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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32

Bagdanavicius, Audrius. "Premixed combustion of alternative fuels under varying conditions of temperature and pressure". Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/54231/.

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Temperature, pressure and CO₂ and H₂ addition to CH₄ effects on turbulent and laminar burning velocity have been found and discussed. Novel turbulent burning velocity determination methods are presented and uncertainties have been discussed. Turbulent burning velocity correlation with nondimensional numbers have been found and flames structures have been analysed.

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33

Finnegan, Stephen. "A life cycle assessment (LCA) of alternative fuels for public service vehicles". Thesis, University of Liverpool, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400224.

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Toulson, Elisa. "Applying alternative fuels in place of hydrogen to the jet ignition process /". Connect to thesis, 2008. http://repository.unimelb.edu.au/10187/3532.

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Park, Sammy Ace. "Combustion instability and active control| Alternative fuels, augmentors, and modeling heat release". Thesis, University of Maryland, College Park, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10129882.

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Experimental and analytical studies were conducted to explore thermo-acoustic coupling during the onset of combustion instability in various air-breathing combustor configurations. These include a laboratory-scale 200-kW dump combustor and a 100-kW augmentor featuring a v-gutter flame holder. They were used to simulate main combustion chambers and afterburners in aero engines, respectively. The three primary themes of this work includes: 1) modeling heat release fluctuations for stability analysis, 2) conducting active combustion control with alternative fuels, and 3) demonstrating practical active control for augmentor instability suppression.

The phenomenon of combustion instabilities remains an unsolved problem in propulsion engines, mainly because of the difficulty in predicting the fluctuating component of heat release without extensive testing. A hybrid model was developed to describe both the temporal and spatial variations in dynamic heat release, using a separation of variables approach that requires only a limited amount of experimental data. The use of sinusoidal basis functions further reduced the amount of data required. When the mean heat release behavior is known, the only experimental data needed for detailed stability analysis is one instantaneous picture of heat release at the peak pressure phase. This model was successfully tested in the dump combustor experiments, reproducing the correct sign of the overall Rayleigh index as well as the remarkably accurate spatial distribution pattern of fluctuating heat release.

Active combustion control was explored for fuel-flexible combustor operation using twelve different jet fuels including bio-synthetic and Fischer-Tropsch types. Analysis done using an actuated spray combustion model revealed that the combustion response times of these fuels were similar. Combined with experimental spray characterizations, this suggested that controller performance should remain effective with various alternative fuels. Active control experiments validated this analysis while demonstrating 50-70\% reduction in the peak spectral amplitude. A new model augmentor was built and tested for combustion dynamics using schlieren and chemiluminescence techniques. Novel active control techniques including pulsed air injection were implemented and the results were compared with the pulsed fuel injection approach. The pulsed injection of secondary air worked just as effectively for suppressing the augmentor instability, setting up the possibility of more efficient actuation strategy.

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Kofi-Opata, Edwina. "Alternative Energy and the Developmental State in Ghana". University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1368117768.

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Cai, Liming [Verfasser]. "Chemical Kinetic Mechanism Development and Optimization for Conventional and Alternative Fuels / Liming Cai". Aachen : Shaker, 2016. http://d-nb.info/1118259327/34.

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Häuptli, Daniel. "Expected development of alternative fuels and drive-train technologies from an integrated perspective". St. Gallen, 2006. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/03603743001/$FILE/03603743001.pdf.

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FONSECA, CLOVIS HENRIQUE M. "SUBSTITUTION OF THE OIL DIESEL BY ALTERNATIVE FUELS IN THE GENERATION OF ELECTRICITY". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=10687@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
Este estudo foi realizado visando avaliar o desempenho de um grupo gerador na geração de energia elétrica nas áreas remotas do Brasil utilizando um combustível renovável, o óleo de dendê in natura. Foi investigado, em laboratório, o comportamento de um motogerador diesel, de 3 kVA ligado a um banco de carga composto por 16 lâmpadas de 150 kW. O desempenho do motor foi avaliado com a utilização do óleo de dendê, tendo como referência o desempenho do mesmo grupo gerador utilizando o óleo diesel. Devido à alta viscosidade do combustível escolhido, foi necessário um pré-aquecimento do mesmo para que esta propriedade fosse semelhante à do diesel. As emissões de poluentes do motor utilizando o óleo vegetal foram em média menores do que com o motor utilizando diesel. No entanto, o consumo específico de combustível do motor utilizando óleo de dendê foi maior que o consumo específico de combustível utilizando o óleo diesel. Além disso, a potência média gerada com o dendê foi a mesma que a potência média gerada com diesel. Isso indica que é possível uma substituição do óleo diesel pelo óleo de dendê in natura nas remotas localidades do país.
This study was carried out aiming the performance assessment of a power generation set using a renewable fuel, the crude palm oil. It was investigated, in laboratory, the performance of a diesel generating set of 3 kVA, supplying power to a load composed of 16 light bulbs of 150kW. The performance of the engine was evaluated with the use of the crude palm oil, having as reference the performance of the same generating set using the diesel oil. Given the high viscosity of the chosen fuel, its preheating was necessary so that this property was similar to the diesel oil.The emissions of pollutants of the engine using the vegetal oil were less than that with the engine using diesel oil. However, the specific fuel consumption of the engine using crude palm oil was greater that the specific fuel consumption using the oil diesel. Moreover, the average power generated with palm oil was equal to the power generated with diesel oil. The performance of the engine was evaluated with the use of the palm oil, having as reference the performance of the same generating group using the diesel oil. The results indicate that it is possible to substitute the diesel oil by the renewable oil.

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40

Chen, Cuicui. "Working towards a future on alternative fuels : the role of the automotive industry". Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/72879.

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Thesis (S.M. in Technology and Policy)-- Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 81-84).
Complementarity of vehicles and fuels has posed significant barrier for increasing the use of alternative fuels in place of traditional ones. An initial positive number of either alternative fuel vehicle (AFV) users or alternative fueling stations are needed for the diffusion of both. This research examines the incentive of the automotive industry, in particular automobile companies focusing on AFVs, to create a positive number of AFV users by demand-side promotion which increases environmental awareness of consumers, and a positive number of alternative fueling stations by supply-side promotion including funding part of the upfront or operating costs of alternative fueling stations. I first build a static microeconomic model of the vehicle and fuel market and find that the demand-side promotion is helpful in creating a positive number of AFVs and alternative fueling stations under a wider range of situations than is supply-side promotion. AFV companies are found to have incentive to do these promotions given affordable promotion costs. Furthermore, using data on vehicle purchase and characteristics of U.S. consumer units from 2005 to 2010 merged with information on state-level fuel prices, fueling stations, and designation of clean cities, I find that the addition of 1 clean city or 100 refueling stations of E85, an alternative fuel used in flex-fuel vehicles, is equivalent to a reduction of $0.04 or $0.19 in the E85 price on the effect of increasing flex-fuel vehicle choice probability respectively. Both the theoretical and empirical results suggest that AFV companies evaluate business opportunities in supply- and demand-side promotions, and that policy makers consider potential contributions of the market to bringing about a future on alternative fuels.
by Cuicui Chen.
S.M.in Technology and Policy

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41

Lobo, Prem. "Impact of alternative fuels on the PM emissions characteristics of gas turbine engines". Thesis, Manchester Metropolitan University, 2015. http://e-space.mmu.ac.uk/595498/.

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The growth in the commercial aviation sector has raised concerns about the impact of emissions from aircraft operations on local and regional air quality, climate change, and health-related effects. The lack of Particulate Matter (PM) emissions data from gas turbine engines coupled with the increasing interest in the use of alternative fuels as a potential emissions mitigation strategy are the motivating factors behind this thesis. A total of seven peer-reviewed archival journal publications form the basis of this work. It commences with two field studies that were performed at the Oakland International Airport and the Hartsfield-Jackson Atlanta International Airport to measure the characteristics of aircraft engine specific PM emissions at the engine exit plane and in the near field as the exhaust plume expands and cools. Having characterised the PM emissions from various aircraft gas turbine engine types, the significant impact that alternative fuels can have on the PM emissions characteristics was explored and the results were correlated with fuel properties. A new robust and standardised methodology for the measurement of non-volatile PM emissions is described, and its reproducibility against other systems is demonstrated. Finally this standardized system was used in a detailed examination of the impact of fuel composition on the characteristics of the emitted non-volatile PM from a gas turbine engine. These publications and the resulting data improved the characterisation and quantification of PM emissions for a wide variety of gas turbine engines burning conventional and alternative fuels. PM emissions from aircraft gas turbine engines at airports were found to have bimodal size distributions, consisting of a nucleation mode with volatile PM and an accumulation mode with volatile PM condensed on the surface of non-volatile PM. Fuel properties were found to have a significant impact on the production of PM. The reductions in PM emissions with alternative fuels were best correlated with fuel hydrogen content. The data and analysis from these publications will be used to improve/validate current environmental impact predictive tools with real world aircraft gas turbine engine specific PM emissions inputs and develop effective emissions mitigation strategies.

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Mielczarek, Detlev Conrad. "Autoxidation behaviour of hydrocarbons in the context of conventional and alternative aviation fuels". Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/10407/.

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This PhD aspired to a develop greater insight into the fundamentals of hydrocarbon autoxidation processes in the context of thermal stability of aviation fuels. A number of approaches to develop a better understanding of the observed processes have been considered. This covers establishing the suitability of an automated reaction mechanism generator to develop autoxidation reaction mechanism as well as manipulating the resultant schemes, for example by lumping species and their associated reactions as well as reaction rate based mechanism reduction. Further a number of postulated interactions between contaminants in fuel and oxidised products in thermally stressed hydrocarbons employing ab initio quantum chemistry methods were examined. Finally a set of systematic experiments was carried out to obtain quantitative data of the effect of a number of additives on the stability of thermally stressed hydrocarbons. These tests employed a small scale test device, the PetroOxy which provides reliable and reproducible experimental data under well defined test conditions. The PetroOxy enabled the collection of samples of the deposition products on metal foils for further analysis under a scanning electron microscope with x-ray dispersive spectroscopy for elemental analysis. This provided both the morphology as well as the elemental distribution of the deposits formed on the foils, offering a first hand look at the differences between deposits formed from different additives. This thesis shows that automated mechanism generation is a suitable method when describing the initial steps of autoxidation processes without any additives. It further shows that the PetroOxy is a very useful tool for obtaining systematic, reliable, experimental data for further analysis.

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Freeman, Charles Ellsworth. "Environmental Responsibility and Financial Performance| Implementing Alternative Fuels in Third-Party Logistics Companies". Thesis, Argosy University/San Francisco Bay Area, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10669619.

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This study involved the use of a quantitative, cross-sectional design to test the tenet of Sustainable Supply Chain Management (SSCM) that connects a logistics organization’s ability to adapt to dwindling natural resources and economic sustainability. Through an examination of the correlation of alternative fuel use and the financial measurement of cost as percent of sales in U.S.-based, publicly traded third party logistics (3PL) companies using 2013 financial data, a statistically significant, strong, negative correlation was affirmed, indicating a correlation between alternative fuel use and improved financial performance. The statistical correlation of implementing alternative fuels and financial performance serves to remove the assumed financial barrier to implementing alternative fuels for logistics practitioners in the context of the impending apocalypse of a global $10.2 trillion transportation system that is fueled by oil that will eventually run out. As a field of study, sustainability in logistics has few theoretical frameworks and there is a clear need for quantitative research to evaluate those that do exist. This study addressed the need for research by adding directly to the body of logistics sustainability knowledge, establishing a template for future research, and reaffirming the need for the standardization of non-financial reporting.

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Sihota, Natasha Julie Jane. "Novel approaches for quantifying source zone natural attenuation of fossil and alternative fuels". Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50105.

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Natural attenuation represents an environmentally and economically sustainable means to manage contaminants in situ. To assess potential human and environmental risks associated with this strategy, there is a need to characterize the extent of contaminant containing source zones. Moreover, to obtain public and regulatory support, there is a need to demonstrate that mass losses are occurring. However, quantifying the extent and rate of natural attenuation under field conditions remain challenging. Here a novel approach for assessing and monitoring sites impacted by hydrocarbon and ethanol-blended fuels using surficial gas effluxes is developed. The approach is tested at several sites including those impacted by a crude oil pipeline rupture, ethanol-blended fuel train car derailments, and historic refinery operations. The approach was refined through inclusion of isotopic measurements, comparison to other approaches for monitoring microbial activity, and evaluation of seasonal dynamics and microbial communities. Process-based reactive transport modeling was used to integrate and interpret field data and develop and illustrate a more robust conceptual model of the processes occurring at the different field sites. Results demonstrate that surficial gas effluxes are able to both delineate contaminant containing source zones, and distinguish between the rates of natural soil respiration and contaminant mineralization. In scenarios where methane oxidation goes to completion, carbon dioxide fluxes are sufficient for evaluating natural attenuation rates; when methane escapes oxidation, measurements of methane fluxes are also needed. Results also demonstrated that measurement of radiocarbon is particularly useful for determining the contribution of contaminant degradation to the measured efflux. Comparison of seasonal dynamics showed that both biological and physical parameters must be considered when quantifying average annual contaminant degradation rates while comparison to other approaches for measuring microbial activity showed good correlations with gas effluxes. Comparison across the field sites investigated, showed degradation rates were relatively high at ethanol-blended fuel release sites. In-depth microbiological evaluation of microbial communities at one ethanol-blended fuel release site showed a substantial change in the microbial community associated with the release. Overall, the novel methods provide a useful approach for assessing the extent and rate of natural attenuation at hydrocarbon contaminated field sites.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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45

Adams, Victor W. "The potential of fuel cells to reduce energy demands and pollution from the UK transport sector". Thesis, Open University, 1998. http://oro.open.ac.uk/19846/.

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Atmospheric carbon dioxide and pollution due to the burning of fossil fuels is increasing. Many scientists attribute global warming to the rising levels of carbon dioxide and other pollutants, some of which also pose risks to health. These can be reduced by the more efficient use of conventional fuels and the development of non-polluting energy resources. Fuel cells offer a highly efficient and low polluting method of generating electricity, and are under development for both the power generation and transport sectors. There is a need to assess (a) emissions from fuel cells using various fuels and (b) ways of introducing such technology to transportation in the near future. Fuel consumption, energy and emissions from the production and use of fuels (hydrogen, methane, propane, petrol, diesel, alcohols and rape methyl ester) are calculated per kilowatt hour of fuel cell output over a range of efficiency. These are compared with those for internal combustion engines with advanced exhaust control and for the recharging of battery driven vehicles. The results, which are applicable to both transport and power generation, enable the best low pollution fuels to be selected and are used to calculate through life emissions for public transport buses. Fuel cells are an ideal solution to reduce pollution from transport, but their commercial development in this field is further away than that for stationary applications. Thus, a transition stage is recommended where fuel cell electrical power stations, based on existing demonstrators, are used to recharge fleets of battery driven vehicles during the development of mobile fuel cell systems. These fleets include public transport and commercial vehicles. Also, fuel cell power stations could provide energy for electric trains. A combined system is proposed where electric trains recharge battery driven commercial vehicles during long journeys. The above proposals would enhance fuel cell development, introducing them alongside current transport systems, possibly using the same fuel.

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Toback, Andrew Todd. "The effect of alternative fuels and aftertreatment devices on measured mobile school bus emissions /". Full text available online, 2007. http://www.lib.rowan.edu/find/theses.

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Ebuy, Teka Axumawi. "Utilization of Alternative Fuels in Cement Pyroprocessing : the Messebo Factory case study in Ethiopia". Thesis, KTH, Kraft- och värmeteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-170132.

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Energy costs and environmental standards encouraged cement manufacturers worldwide to evaluate to what extent conventional fuels (Furnace oil, Coal and Petcock) can be replaced by alternative fuels in cement production, i.e. biomass or processed waste materials like sewage sludge, MSW (municipal solid waste), Refuse Derived Fuels (RDF), Tire Derived Fuel (TDF), Plastic Derived Fuel (PDF), Biomass Derived Fuels (BDF), meat and bone meal (MBM), etc. High temperature of >1500 C, long residence times of up to 10 seconds and high turbulence in the cement kiln ensure complete destruction of organic constituents in the waste materials. The main benefits of using solid alternative fuels in cement kilns include enhanced energy recovery and conservation of non-renewable fossil fuels which in other words translates into an immediate reduction of greenhouse gas emissions related not only to conventional fuel mining and utilization but also helping the cement industry to clear its image of being among the most polluting and CO2 emitting industries. Most notably, a reduction in cement production costs is also expected. Varying amounts of different alternative fuels have been studied in this thesis and referred to an actual cement plant in Ethiopia, located in the northern province of Mekelle. The availability of alternative fuels in the region has been estimated. Calculations have been performed for the comparison with the reference case for each alternative fuel option. Possible technical challenges in the combustion process and the supply feed chain as well as in the resource base have been identified. The environmental benefits for the reference plant and the impact on cement costs have been evaluated and discussed. The results show a clear advantage for alternative fuel utilization, both in terms of environmental parameters and also in production costs for the cement plant.

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48

JAMSHAID, ASHIQ MUHAMMAD. "Influence of alternative fuels on the formation of dioxins in a cement production plant". Thesis, Umeå universitet, Kemiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-89026.

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49

Ushakov, Sergey. "Particulate matter emission characteristics from diesel engines operating on conventional and alternative marine fuels". Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-20042.

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The awareness of adverse health effects associated with diesel aerosol emissions has generated a great public and academic interest in studying various aerosol-producing sources. While automotive industry has achieved significant progress in controlling and reducing particulate matter (PM) emissions, there was only a very limited attention paid to ship transport, i.e. to marine diesel engines (MDE). Nowadays, shipping is one of the biggest contributors of PM emissions to the atmosphere, although is still lacking attention from PM legislators and diesels aerosol researchers. This thesis is focused on measurement and characterization of particulate emissions from diesel engines (both marine and heavy-duty) operating on conventional and alternative marine fuels. Different PM emission characteristics such as particle size distributions, total and nanoparticle concentrations, PM mass and particle morphology were measured and analysed in current thesis. The observed significant differences in PM results between 2-stroke and 4-stroke marine diesel engines indicate the importance of engine technology, while pronounced contribution of heavy fuel oil’s ash fraction (in contrast to MGO) to solid PM reveals the importance of considering the fuel factor. In addition, PM characteristics from marine diesel engines were found to be different from that of heavy-duty engine, but a certain, somewhat surprising, agreement between results for 4- stroke MDE and 4-stroke heavy-duty engine was also observed. Particle morphology analysis confirmed the three main origins (sources) of particulates: fuel, lubrication oil and mechanical wear of moving cylinder parts. The sole effect of high sulphur level in marine fuels was studies using a sulphur-doping of a reference low-sulphur MGO up to 4% S by mass. The contribution of sulphur to PM mass appeared to be more pronounced than is known from automotive engine studies. The homogeneous nucleation of sulphur and HC compounds was observed only at very low load conditions, while heterogeneous nucleation, i.e. condensation on the surface of existing solid particles, was found to be the dominating mechanism and can be associated with a rather low turbulence level in a primary porous tube diluter and availability of considerable amount of solid nucleus. As volatile particles are very sensitive to dilution parameters and in order to obtain repeatable and reproducible results, the effects of primary dilution ratio (PDR) and primary dilution air temperature (PDT) were studied. Both these parameters showed no effect on solid carbonaceous particles formed inside the engine cylinders, and at the same time were vital for semivolatile HC and sulphur compounds. Increase in PDR reduces the partial pressure of volatile compounds, and hence their tendency to nucleate; too low PDR should be avoided as water condensation can occur leading to some deceptive results. Increasing PDT results in increased saturation vapour pressure of volatile compounds, which is also suppressing nucleation. Effect of filter media on the results of gravimetric PM analysis was studied and no filter type was found overwhelmingly superior due to various positive and/or negative artifacts associated with each filter type. The environmental benefits in terms of gaseous, smoke and PM emissions of fish oil (FO) biofuel and GTL synthetic fuel as alternatives to conventional MGO were investigated. A fairly good ignition and combustion properties together with excellent emission characteristics were observed in case of FO, which although requires some additional testing of its rheological and cold temperature properties and oxidation stability. GTL fuel showed reduction in PM mass, smoke and all gaseous emissions except THC, which together with registered particle number concentration showed a visible increase. This can be associated with possible higher incidence of wall-wetting by GTL fuel as its volumetric flow rates were increased to compensate for lower fuel density (lower volumetric energy content). Injection system tuning/modification or shift to common rail injection system can be proposed for reduction of gaseous (especially THC) and PM emissions even further.

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Sagar, Ambuj Daya. "Automobiles and global warming : alternative fuels and other options for carbon dioxide emissions reduction". Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/11694.

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