Dissertations / Theses: 'Marine fuels'

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Anastasakis, Konstantinos. "The potential of the production of fuels and chemicals from marine biomass." Thesis, University of Leeds, 2011. http://etheses.whiterose.ac.uk/4167/.

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The need for sustainability, energy security and reduction of global warming has brought many alternative energy sources into the foreground. Already there are well established technologies that can produce renewable energy but when it comes to the production of renewable liquid fuels and chemicals, biomass is the primary feedstock. Biomass is a renewable source of energy that can provide heat, electricity and transport fuels. However, utilisation of biomass posses some limitations such as land availability and competition of energy crops with food crops. In order to overcome these problems "third generation" biofuels from alternative feedstock such as macro-algae have recently come into the foreground. Oceans and seas cover over 70% of the earth's surface, most of which is under exploited, resulting in additional potential for biomass production. This thesis concentrates on the potential for production of bio-energy and chemicals from macro-algae through thermochemical processes such as pyrolysis, combustion and hydrothermal liquefaction. Utilisation of aquatic biomass for production of bioenergy is a very recent concept and there is a lack of information on their thermochemical behaviour. This investigation contributes to a wider study and forms part of the Supergen II bionergy programme investigating the potential for utilisation of macrolage in the UK. This investigation includes a detailed characterisation of the fuel properties and thermal behaviour of a range of wild seaweeds around the UK provided by the Scottish Association of Marine Sciences. In addition, a range of model biochemical components have been investigated, in particular, the model carbohydrates present in macro-algae. Alginic acid, mannitol, laminarin, fucoidan and cellulose are the main carbohydrates present in brown macro-algae. The rest of the plant material comprises of protein and ash. Freshly harvested macro-algae contain 80-90wt% moisture. Their ash content is high, reflecting their high inorganic content. Potassium is the most abundant metal present in macro-algae although other metals are also present including sodium, calcium, magnesium, Their carbohydrate, protein and ash content undergo a seasonal variation during their growth cycle. This variation was found to affect their properties as fuel. Carbon content reaches its maximum during summer - early autumn. During the same period, the inorganic (and thus ash) content is at its minimum suggesting summer - early autumn as the optimum period for harvesting macro-algae for bioenergy. The high carbon and low inorganic content during this period is reflected in its higher heating value but it is still relatively low (13-14 MJ/kg) when compared with terrestrial biomass. The nature of the inhabitant location was found to significantly influence macro-algae fuel properties with samples grown in the open ocean having better fuel properties (higher HHV and lower inorganic content) than samples growing in canals and estuaries. Investigation of the pyrolysis behaviour was performed using thermal analysis such as TGA and Py-GC/MS. The volatile matter evolved during pyrolysis was higher for samples collected during summer and early spring due to their higher carbon content. The main volatiles evolved during decomposition were found to originate either from their carbohydrates or from their protein content. Specific marker compounds were identified for the carbohydrates such as dianhydromannitol, 1-(2-furanyl)-ethanone, 2-hydroxy-3-methyl-2-cyclopenten-1-one and furfural for manitol, laminarin and alginic acid respectively. Proteins are found to produce a range of indoles and pyrroles. Some of the compounds identified may have industrial applications indicating the possibility of producing chemicals through pyrolysis of macro-algae. The high moisture content of seaweed necessitates that significant amounts of water must be removed before this feedstock can be converted by pyrolysis. The high moisture content is similary an issue for combustion which has been assessed by a combination of TGA and characterisation of the biomass. Macro-algae have a low HHV, high halogen content and high ash content and are predicted to have high slagging and fouling behaviour in conventional combustion chambers. This fouling behaviour is predicted through empirical indexes such as the alkali index and is shown to be higher than terrestrial biomass even during summer - early autumn when their inorganic content is at minimum. Typical ash contents vary from 18 to 45wt% and contain mainly oxides of K20, Na2O, CaO and MgO. Pre-treatment prior to combustion can significantly reduce the ash content leading to improved combustion properties, but this also leads to removal of some biochemical components. Using an acid pre-treatment, some of the seaweed's biopolymers, such as mannitol or fucoidan, can be removed presenting the possibility for acquiring valuable chemicals from seaweed before combustion of the residue. An alternative processing route, capable of processing wet feedstocks called hydrothermal liquefaction (HTL) involves the processing of the macro-algae in subcritical water. HTL converts the starting material into four product streams including a bio-crude, a char, an aqueous stream consisting primarily of process water and a gaseous stream. A parametric study of HTL has been investigated using high pressure batch reactors with or without the presence of catalysts. The bio-crude produced from the liquefaction of macrolgae was found to have a high heating value and resembling chemical composition to crude-oil. It can be used directly as a fuel however it still contains significantly high nitrogen levels and will required suitable upgrading (e. g. denitrogenation). The bio-char was found to also have a high heating value. Both bio-crude and bio-char produced from HTL are virtually free of alkali metals suggesting they are suitable for combustion. Reaction conditions such as temperature and the ratio of biomass to water have the greatest influence on product yields and properties. Typical bio-crude yields were in the range of 10 to 19wt% on a daf basis with their HHVs ranging from 32 to 38 MJ/kg. The yields of bio-chars were in similar range (IOwt% to 19wt% on a db) with HHVs between 10 and 26 MJ/kg. An energy balance was calculated in order to investigate the energy required to heat the mixture of macro-algae and water. The energy recovery in the bio-crude and bio-char was relatively low, between 50 and 65%, indicating that a significant portion of the energy content of macro-algae is passing in to the other product streams. The aqueous phase (process water) was found to be rich in metals, especially alkali metals, and sugars, and its composition suggests it maybe possible to utilize it as a fertilizer. A fraction of the sugars present in macro algae (mannitol and laminarin) pass in to the aqueous stream, suggesting there is also potential for fermentetion to bioethanol. The gaseous stream is composed mainly of CO2, N, CO and lower concentrationso H and CH4. The most suitable thermochemical processing route for macro-algae is proposed to be hydrothermal liquefaction and has potential for utilization of all the product streams producing fuels and chemicals using a bio-refinery concept.

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Lock, Lillie Marlén. "Future fuel for worldwide tankershipping in spot market." Thesis, KTH, Marina system, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121509.

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Ship exhausts contain high levels of sulphur oxides, nitrogen oxides, carbon dioxide and particles dueto the heavy fuel oil, HFO, used for combustion and the combustion characteristics of the engine.As a result of upcoming stricter regulations for shipping pollution, as well as growing attentionto greenhouse gas emissions, air pollution and uncertainty of future petroleum oil supply, a shifttowards a cleaner burning fuel is needed.This work explores potential alternative fuels, both conventional and unconventional, and abatementtechnologies, to be used by tankers in the worldwide spot market to comply with upcomingenvironmental regulations in the near and coming future. As a reference the product tanker M/TGotland Marieann is used and recommendations for which fuel that shall be used by the referenceship in 2015 and 2020 are presented.The environmental assessment and evaluation of the fuels are done from a life cycle perspective usingresults from Life Cycle Assessment, LCA, studies.This study illustrates that, of the various alternatives, methanol appears to be the best candidatefor long-term, widespread replacement of petroleum-based fuels within tanker shipping. It does notemit any sulphur oxides nor particles and the nitrogen oxides are shown to be lower than those ofmarine gas oil, MGO. The global warming potential of the natural gas produced methanol is notlower than that of MGO, but when gradually switching to bio-methanol the greenhouse gas emissionsare decreasing and with methanol the vision of a carbon free society can be reached.For 2015 a switch towards methanol is not seen as realistic. Further research and establishment ofregulations and distribution systems are needed, however there are indications that a shift will bepossible sometime between 2015 and 2020. For 2015 a shift towards MGO is suggested as it involveslow investment costs and there is no need for infrastructure changes. As MGO is more expensivethan methanol, a shift is preferable as soon as the market, technology and infrastructure are ready.

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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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Houda, Sara. "Oxidative desulfurization of marine fuels : optimization of reaction conditions and development of efficient catalysts." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1R064.

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L'Organisation Maritime Internationale (OMI) a limité la teneur en soufre des combustibles marins dans les zones de contrôle des émissions de soufre (zones SECA) de 1 à 0,1 % en 2015 et la limitera, d’ici 2020, de 3,5 à 0,5 % dans toutes les zones maritimes. Les fiouls marins sont constitués des résidus lourds caractérisés par une teneur élevée en soufre, la majeure partie du soufre se trouvant dans des molécules dites réfractaires, très difficiles à éliminer par le procédé d'hydrodésulfuration existant, fonctionnant sous haute pression d’hydrogène. Cependant, ces molécules soufrées sont connues pour être plus réactives dans le procédé de désulfuration oxydante ou oxydésulfuration (ODS), réalisé dans des conditions douces sans consommation d'hydrogène. L'objectif de cette thèse est de proposer une désulfuration des fiouls marins par ODS. Toutefois, l’ODS sur les fiouls lourds est encore immature et les fiouls marins restent peu étudiés avec peu de publications reportées dans la littérature. Les travaux de cette thèse se sont donc tout d’abord portés sur le développement d'une méthodologie fiable pour l'analyse des composés soufrés dans les combustibles marins, avant une étude pour la détermination d’un catalyseur efficace et approprié, couplée à l'optimisation des conditions opératoires. Parmi une large variété de fiouls marins, trois fiouls ont été choisis, caractérisés par une viscosité élevée variant de 380 à 700 cSt. Les résultats d’analyse chimique ont révélé des teneurs élevées en soufre entre 0,6 et 3,2 % reflétant la variabilité de composition des combustibles marins. La réaction d'ODS a été effectuée par catalyse hétérogène à l'aide du système MoO3/Al2O3-H2O2 dans un réacteur batch. Les effets du temps de réaction, du rapport molaire oxydant/soufre (Ox/S) et du solvant d'extraction ont été étudiés. Le couplage des ultrasons avec l’ODS classique a permis d'obtenir de meilleurs taux de désulfuration grâce à l'effet de synergie amené par l’utilisation des ultrasons. Des études sur les effets de la teneur en molybdène, du dopage au phosphore et/ou au vanadium et du type de précurseur du molybdène ont été réalisées sur le catalyseur molybdène sur alumine. D'autres supports oxydes ont également été utilisés, améliorant considérablement les performances catalytiques. Dans des conditions de réaction optimales et avec les catalyseurs les plus efficaces, il a été possible d'oxyder toutes les charges sélectionnées et de les désulfurer pour les rendre compatibles avec les nouvelles normes 2020
The International Maritime Organization (IMO) has limited marine fuel sulfur content in Sulfur Emission Control Areas (SECAs) from 1 to 0.1 wt.% in 2015 and will limit marine fuel sulfur content from 3.5 to 0.5 wt.% in all maritime areas by 2020. Marine fuels consist of heavy oils characterized by high sulfur content with refractory sulfur compounds difficult to remove using existing conventional high pressure hydrodesulfurization processes. However, these sulfides molecules appeared more reactive in oxidative desulfurization (ODS) process, carried out at mild conditions without hydrogen consumption. The objective of this thesis is to propose an oxidative desulfurization method of marine fuels. Nevertheless, ODS on heavy fuels is still immature and marine fuels are poorly studied with only few publications reported in literature. This work first focused on the development of a reliable methodology for the analysis of sulfur compounds in marine fuels before the study of an appropriate and efficient catalyst for marine fuel ODS reaction with optimized operating conditions. Among a large variety of marine fuels, three marine fuels were chosen with high viscosities that varied from 380 to 700 cSt. The results of chemical analysis revealed high sulfur content ranging from 0.6 to 3.2 wt.% reflecting the variability of the composition of marine fuels. ODS reaction was carried out by heterogeneous catalysis using MoO3/Al2O3-H2O2 system in batch reactor. The effects of reaction time, oxidant to sulfur molar ratio (Ox/S) and extracting solvent were investigated. Ultrasound assisted oxidative desulfurization coupled to normal mixing provided better desulfurization rates due to the synergetic effect provided by ultrasounds. Studies on the effects of molybdenum loading, phosphorus and/or vanadium doping and molybdenum precursor type were carried out on the alumina-supported molybdenum catalyst. Others oxide carriers were also employed, remarkably improving catalytic performances. Under the optimum conditions and with the most efficient catalysts, it was possible to oxidize and desulfurize all selected feeds making them compatible with the 2020 new regulations

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Clague, Nicholas Paul. "Determination of the core structure of overbased calixarenes used as detergent additives in marine fuels." Thesis, University of Hull, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310215.

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Jawara, Lamin. "Prediction of DI-CI Engine Performance and Emission Characteristics of Varying Renewable Diesel Fuels with Experimental Results from Marine Diesel fuel." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16234.

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This paper discusses finding of combustion research carried out using Ricardo hydra research diesel engine with varying renewable fuels. The primary fuel of investigation is rapeseed methyl ester (RME) and marine diesel fuel (MDO) was used as the primary reference fuel (PRF). The results of the PRF have been acquired by experiment and have been used to characterize the heat release rates, brake fuel conversion efficiency (BFCE), brake specific fuel consumption (BSFC), brake fuel energy consumption (BSEC), exhaust temperature; Oxides of nitrogen (NOx), carbon monoxide (CO), carbon dioxide (CO2) and hydrocarbon (HC) emissions have also been studied. Empirical correlations have been developed and used to predict the corresponding results with several blends of renewable fuels. The analysis of the results showed a good correlation between the results of the MDO and the blends of the renewable fuels. The results showed that the difference between mean BSFC of the MDO and the predicted values of the blend of the liquefied petroleum and 10% rapeseed (LGO-10) was only 0.82%. Predicted values for B20, B40 and B100 were 1.65%, 3.33% and 8.53% respectively. At maximum load the predicted lost in power for LGO-10 ranges from 0.88% at maximum speed to 0.85% at low speed. The predicted lost in power for B20, B40 and B100 were 1.61%, 3.21% and 7.86% respectively at maximum speed and 1.71%, 3.13% and 7.86% respectively at low speed range. The mean increase between the measured mean NOx emission from MDO and the LGO-10 was 0.98%, while CO and CO2 emissions fall by 6.35%. There was also a mean reduction of HC emission by 10.59%. Similar changes have been predicted in B20 and B40 emissions.

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Worren, Henrik. "Technical solutions regarding impementation of the EU directive 2005/33/EC concerning sulphur content of marine fuels." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11630.

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The objective of this diploma thesis is to assess the technical and operational challenges EU Directive 2005/33/EC will introduce. This is done using fundamental knowledge about naval architecture and marine diesel engines. Experiences on 0,1 % sulphur fuel in the maritime industry is limited, established standards and practices are few and is now being developed. EU Directive 2005/33/EC is dictating vessels to use fuel with a maximum sulphur content of 0,1 % while in EU port. MGO (type DMA) is the only fuel available with a sulphur content below 0,1 %. Vessels managed by WSMN are calling an EU port frequently and have to do necessary modification to their vessels for safe compliance to the directive. Today their vessels are carrying HFO and MDO, after complying with the directive, they shall carry HFO and MGO; MDO will be exchanged with MGO. MGO got different properties from MDO. The main difference is low viscosity. Low viscosity can be compensated by cooling the fuel before use, installing a cooler before engine inlet. Poor lubricity is also an area of concern, lubricity additives available on the market may be used. Poor lubricity properties is from the production process in the refineries, hydrotreating is used to achieve 0,1 % sulphur content and is removing the fuel’s natural lubricity. Marine fuels are tested against ISO 8217. This standard has several deficiencies and missing vital information on ignition/combustion properties. C/H (carbon/hydrogen) ratio is the most accurate indicator on this area. It is therefore recommended to upgrade a normal fuel sample analysis to include C/H ratio. Equipment most affected by the new properties is pumps; injection pumps and booster-/supply pumps. Lower viscosity can increase the internal leakages and delivered flow and pressure will decrease. How each vessel is affected it mainly determined by the injection system’s condition. The better the condition is, its ability to deal with low viscosity fuels is better On a general basis, manufacturers and class societies shall be consulted and modifications approved.

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Mayakoti, Amukta. "Characterization of Fresh Water Microalgae from East Tennessee for Biodiesel Production." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etd/1426.

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There is an increasing need for renewable energy sources to replace fossils fuels which accumulate harmful byproducts in the environment. Biodiesel emits less gaseous pollutants than diesel. There are various sources for biodiesel but they are unable to meet the existing demands for fuel. Microalgae are a promising source for biodiesel because of its relatively faster growth rate, availability, and lipid content. Microalgae (JC and BT) growing in local water bodies were collected, selected on section media containing antibiotics, and used for characterizations. Experiments were conducted to study and evaluate the optimum growing conditions. Results show that both JC and BT attain maximum growth with shaking and additional aeration compared to control microalgae Dunaliella salina, Nannochlorposis oculata which do not require additional aeration for optimal growth. Lipid extraction results suggest that JC (9.7%) and BT (4.1%) have slightly higher lipid content compared to control algae e.g. Chlamydomonas reinhardtii (3.1%).

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Filho, Gilberto Dória do Valle. "Avaliação das instalações de máquinas em navios visando redução do uso de combustível fóssil." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-11082011-131221/.

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Este trabalho trata da questão da redução de consumo de combustível fóssil em instalações de máquinas de navios. É um tema de grande interesse no momento, devido ao alto custo operacional e à emissão de poluentes decorrentes do processo da combustão desses derivados de petróleo. Apresenta-se, inicialmente o cenário atual e tendências futuras das instalações propulsoras convencionais que usam óleo pesado ou Diesel. Em seguida, são examinadas alternativas propostas para redução de consumo de combustíveis fósseis nos navios, que são enquadradas em três categorias. A primeira delas envolve possíveis melhorias de projeto para redução da demanda de energia. As outras categorias se referem ao emprego de fontes alternativas de energia, que introduzem uma força propulsora adicional, reduzindo o empuxo requerido do hélice, ou uma potência suplementar no eixo propulsor. Em ambos os casos há também uma redução de demanda de potência requerida do motor Diesel. Na seqüência, são apresentados e discutidos fundamentos termodinâmicos, com ênfase nas análises energética e exergética, como ferramentas para avaliação das máquinas dos navios. A análise exergética, diferentemente do enfoque apenas energético, é a ferramenta mais apropriada para tratar as questões ligadas ao meio ambiente, pois a própria definição de exergia está relacionada com o ambiente de referência. Finalmente, utilizando dados de um navio porta contêineres da frota nacional, é exercitado um exemplo de aplicação com as análises termodinâmicas do motor de propulsão; são também avaliadas e simuladas as diversas alternativas de melhorias e novas fontes de energia, que visam a redução de consumo de combustível fóssil.
This work addresses the issue of reduction of fossil fuel use on ship machinery. Presently it is an interesting topic due to high operational cost and the pollution emissions generated by the combustion process. Initially, it is introduced the present scenario and future trends regarding conventional ship machinery that use heavy or diesel fuel oil. In the sequence, the proposed alternatives for reducing the use of fossil fuel on ships are presented and examined. These alternatives are classified into three categories. The first category comprises possible improvements to the design of ships for reduction of total energy demand. The other categories refer to the use of alternative energy sources, that produce and additional force on the ship reducing the required propeller thrust; or a supplementary power added to the propulsion shaft. For both cases there is also a reduction in the power required from the Diesel engine. Afterwards, the pertaining thermodynamics theory is revised and discussed with focus on the energy and exergy analysis as aid tools for evaluation of ship machinery. The energetic analysis, different from the sole energetic focus, is the most applicable tool to be employed for environmental issues as the self definition of exergy relates to an environment reference. Finally, using data from a typical container ship belonging to the national fleet, an application example using the thermodynamic analysis is performed to the propulsion main engine; as well as it is also simulated several alternative conditions for improvements and new energy sources, aiming to the reduction of fossil fuel consumption.

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Delashob, Hemen, and Björn Elmström. "Liquified Natural Gas Marine Fuel : Naturally Occuring Radioactive Material." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-84206.

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There seems to be enough information available on how different types of radiation may affect human health. There also seems to be adequate research made about NORM and how to handle this phenomenon. The image put forth by this study shows that the appearance of NORM within affected industries do not appear surprising or difficult to deal with. On the contrary it seems to be a well-known issue and safety measures have been adapted accordingly. It appears as if these issues have been overlooked regarding the systems where LNG is being used as a marine fuel. There is not enough data to conclude whether NORM is an issue or not in such systems.

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Blackert, Erik. "Total Cost of Ownership For a Marine Fuel System." Thesis, KTH, Marina system, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-290162.

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The modern marine fuel system have a vital part in preparing the fuel before it can enter theengines. Hard particles and water are removed and the viscosity needs to meet limitationsof the engines, to prevent damage. The cost for operating the fuel system and wear on theengine varies depending on how the fuel system are operated and on surrounding parameters.This thesis explains the cost impact of di erent parameters on the total cost for operating afuel system and aims to create a total cost of ownership model that also considers the costsfor systems connected to the fuel system.The total cost of ownership model includes capital expenses for the equipment and the operationalexpenses in form of; energy, service, sludge storage, water production, risk and alsoincreased costs on connected systems.The result of this total cost of ownership research shows that even if there are an increasedcost for operating the fuel system itself for highest performance will the total cost of ownershipwhen considering connected systems be lower. The user are therefore always recommendedto aim for maximum separation of hard particles to decrease the cost for enginewear and to lower the total cost of risk for a breakdown. The total energy consumption forthe fuel system can be decreased by up to 15% when variable ow control are used on thesupply pumps and meanwhile increase the separation eciency.
Det moderna bränslesystemet har en viktig roll i att förbereda bränslet innan det kan förbrännas i fartygets motorer. Hårda partiklar och vatten avlägsnas, viskositeten måste också hållas inom motorernas tillåtna gränser för att motverka slitage. Användare kostnaden för ett bränslesystem varier beroende på hur det används samt av vissa utomståendeparametrar. Den här analysen av totala ägandekostnaden är gjord för att kunna kopplakostnader på kringliggande system ombord med hur bränslesystemet används. Den totala ägandekostnadsmodellen innehåller inköpskostnader för bränslesystemet samt användare kostnaden i form av; energi, service, slamförvaring, vattentillverkning, kostnaden för risk och kostnaden på kringliggande system ombord. Resultatet av analysen är att ökade driftkostnader för bränslesystemet kan motiveras i form av att kostnaden för kringliggande system sjunker när bränslesystemet fungerar optimalt. Användaren kan därför rekommenderas att alltid sträva efter att få ut den fulla potentialen för bränslesystemet för att spara in på kostnader så som motorslitage och risk för motorhaveri. Den totala energiförbrukningen för bränslesystemet kan förväntas sjunka med 15% om pumpar med variabelt öde används till separatorerna samtidigt som separeringseffektiviteten ökar

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Gustafsson, Filip. "Waste heat recovery systems : Fuel energy utilisation for a marine defence platform." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-19681.

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This report is a thesis for BTH in collaboration with the company Saab Kockums AB. In order to meet future environmental and economical demands, a vessel must reduce its fuel consumption to have a smaller climate impact and save money. Waste heat recovery systems (WHRS) captures the thermal energy generated from a process that is not used but dumped into the environment and transfers it back to the system. Thermal energy storage (TES) is the method of storing thermal energy which allows heat to be used whenever necessary. Some applications of TES are seasonal storage, where summer heat is stored for use in the winter or when ice is produced during off-peak periods and used for cooling later. The purpose of this study is to investigate the possibilities of utilising a vessel’s waste heat by converting thermal energy into electrical energy. This thesis also aims to investigate conditions for SaltX Technology’s nano-coated salt as a potential solution for thermal energy storage. Initially, the expectations and requirements a future WHRS were investigated in a function analysis. Continuously, the method consisted of a combination of a literature review and dialogue with stakeholders. The literature review was used as a tool to identify, select and study concepts of interest built on scientifically proven facts. Dialogues with stake holders were held as a complement to the literature study to find information. The study showed that an organic Rankine cycle has the highest efficiency for low-medium temperature heat and is therefore most suitable to recover thermal energy from the cooling water. The concept of a steam Rankine cycle is most suitable for recovering thermal energy from the exhaust gases for direct use.The study obtained conditions and important properties for storing thermal energy in salt for later use. Finally, the result showed that a Stirling engine is the most efficient concept for conversion of stored energy into electrical energy. The conclusions are that there are great possibilities for waste heat recovery on marine defence platforms. A Stirling engine for energy conversion in combinations with thermal energy storage shows most promise as a future waste heat recovery system on this type of marine platform.
Denna rapport är ett examensarbete för BTH i samarbete med företaget Saab Kockums AB. Arbetet utforskar möjligheterna att möta framtida miljömässiga och ekonomiska krav genom att låta fartyg minska sin bränsleförbrukning. System för återvinning av spillvärme (WHRS) fångar upp värmeenergi som vanligtvis kyls ner eller släpps ut i naturen och för den tillbaka till systemet. Termisk energilagring (TES) är metoder för lagring av värme som gör det möjligt att använda termisk energi när det behövs. Vissa applikationer av TES är säsongslagring, där sommarvärme lagras för användning på vintern eller när is produceras under vintern och används för kylning senare. Syftet med denna studie är att undersöka möjligheterna att utnyttja ett fartygs spillvärme genom att omvandla termisk energi till elektrisk energi. Detta examensarbete syftar också till att undersöka förhållandena för hur SaltX Technology’s nanobelagda salt kan användas som en potentiell lösning för lagring av termisk energi. Inledningsvis undersöktes WHRS:s förväntningar och krav i en funktionsanalys. Fortsättningsvis bestod metoden av en kombination av en litteraturstudie och dialoger med intressenter. Litteraturstudien användes som ett verktyg för att identifiera, välja och studera intressanta koncept baserade på vetenskapligt beprövade fakta. Dialoger hölls som ett komplement till litteraturstudien för att hitta information. Studien visade att en organisk Rankine-cykel har den högsta verkningsgraden för låg-medelhög temperatur och därför är bäst lämpad för att återvinna energi buren i kylvattnet samt att en ång-Rankine-cykel är bäst lämpad för att utnyttja energin från avgaserna för direkt användning. Studien erhöll förhållanden för termisk energilagring i salt samt viktiga parametrar för systemet. Slutligen visade resultatet att en Stirlingmotor är det mest effektiva konceptet för omvandling av lagrad energi till elektrisk energi. Slutsatserna är att det finns stora möjligheter för återvinning av restvärme på marina försvarsplattformar. En Stirlingmotor för energiomvandling i kombination med termisk energilagring visar störst potential som ett framtida system för återvinning av spillvärme på denna typen av plattformar.

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Bruun, Kristine. "Bond Graph Modelling of Fuel Cells for Marine Power Plants." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-6559.

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There is a constant search for alternative solutions improving the fuel efficiency and environmental impact of marine power plants. Fuel cells are regarded as a potential future candidate for significantly reducing pollution from such systems. In this thesis a bond graph template for mathematical modelling of fuel cells is developed. To show the applicability of this template, models of a solid oxide fuel cell (SOFC) system are implemented and simulations carried out. The models are intended for analyses of marine power production in overall ship system applications. The models developed in this thesis can simulate the transient behaviour of a SOFC. These models are developed from fundamental physical relations, resulting in an improved understanding of the high temperature fuel cell, its possibilities and limitations, in the overall power plant. Fuel cells increase the system complexity, and the template provides an important tool for evaluating system performance under various operating conditions. Main findings of this thesis are; 􀂃 Bond graphs are identified as a good tool for the multi-domain nature of fuel cell modelling. Pseudo-bond graphs are chosen to model thermofluid properties while true bond graphs are the choice for electrochemical and electrical domains. 􀂃 A new bond graph element (R-field) is developed, enabling a straight forward conversion between the thermofluid and electrochemical domains. 􀂃 By expanding the lumped model approach, a new type of model is developed enabling simulations of distributed characteristics inside the fuel cell. Typical distributed variables of interest are pressure, temperature and concentration of gas components. 􀂃 The bond graph tool strongly supports the model implementation process when evaluating different ways of representing electrochemical losses. The resulting models are of complete integral causality, lending themselves to computationally efficient system simulations. Component models of the gas supply system is also developed and implemented, permitting simulations of the fuel cell stack under realistic operating conditions. Both the fuel cell template and the support system components provide a basis for implementing other types of fuel cells using the bond graph language.

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Östling, Erik. "Model on degradation of PEM fuel cells in marine applications." Thesis, KTH, Kemiteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299446.

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Sjöfarten står för 3 % av världens totala växthusgaser och är idag högst beroende av fossila bränslen. Ett alternativ för att gå över till en fossilfri flotta är användning av bränsleceller och vätgas som drivmedel. Om vätgasen produceras från elektrolys med förnyelsebara energikällor så är driften utsläppsfri och koldioxidneutral. Bränsleceller kan användas i många olika sammanhang, men har ännu inte slagit igenom med full kraft. En anledning till detta är livslängden som är för kort. För att sjöfarten ska kunna implementera bränslecellsdrift behöver nedbrytningen av bränslecellen bli vidare utforskad och motverkad. Syftet med detta examensarbete var att hitta de mest signifikanta nedbrytningsmekanismerna för sjöfarten samt att bygga en modell för att förutspå livslängden utifrån lastprofiler från fartyg. Rapportens avgränsningar var att enbart studera PEM-bränsleceller tack vare dess höga energitäthet och att teknologin är närmast marknaden för mobila applikationer. En litteraturstudie genomfördes för att fastställa de viktigaste nedbrytningsmekanismerna samt de faktorer som begränsar livslängden. Dessa bestämdes till start/stop cykler samt lastcykler vilka försämrar konduktiviteten i membranet samt minskar den elektrokemiska ytarean. En empirisk modell från experiment från litteraturen etablerades för att hitta relationen mellan parametrarna konduktivitet och elektrokemisk ytarea som funktion av start/stop cykler respektive lastcykler. En Comsol-modell användes för att utvärdera bränslecellens prestanda med dessa försämrade parametrar. Två lastprofiler analyserades och tolkades som antal start/stop cykler samt lastcykler för att utvärdera prestandan som funktion av antal år i drift. Båda fallen var i drift till dess att prestandan minskat med 20 % utvärderat vid strömtätheten 0.6 A/cm2. Båda lastprofilerna var utvärdera med olika körstrategier för att jämföra den modellerade livslängden beroende på ingångsvärden. Den första lastprofilen delades in i Case 1a och Case 1b där antalet start/stop cykler och lastcykler varierade. Resultatet visade att antalet timmar i drift mer än tredubblades i Case 1b där båda ingående indata hade minskats. Case 2 delades upp i tre olika körstrategier där Case 2a var en referens som jämfördes mot Case 2b respektive Case 2c. Skillnaden mot Case 2b var att antalet start/stop cykler per dag multiplicerades med faktor 4. Resultatet från modellen var att livstiden minskade från 6 till 4 år. Vidare utvärderades Case 2c där istället antalet lastcykler dividerades med faktor 4, allt annat identiskt med Case 2a. Utfallet var en ökad livslängd från 6 år till 11 år, med totalt 32 032 timmar i drift. Denna livslängd kan jämföras med kommersialiserade marina produkter från Ballard och Powercell, där livslängden är 30 000 respektive 20 000 timmar i drift. Sammanfattningsvis kan det konstateras att både start/stop cykler och lastcykler bryter ner bränslecellen och därmed minskar dess prestanda. Lastcykler var den faktor som var mest förödande gällande livslängden. Den modellerade livslängden på 32 032 timmar indikerar att den empirisk modellen tillsammans med Comsol-modellen genererade realistiska resultat. Slutligen kan sägas att ett område för framtida forskning inom ämnet innefattar lastcykler eftersom denna hade störst påverkan på modellen. Att särskilja olika typer av lastcykler och koppla till olika degradering skulle skapa än mer förståelse för livslängden. Då denna studie genomfördes på bränslecellsnivå skulle framtida studier kunna inkludera att analysera degradering på systemnivå för att få mer insikt i dessa processer.
The shipping industry emits 3 % of the global GHG-emissions and is highly dependent on fossil fuels. One alternative to decarbonise the sector is by utilising hydrogen in fuel cells. The propulsion is free from emissions if hydrogen is produced from renewables. The fuel cell technology can be applied in various applications but have not been fully commercialised. One of the biggest bottlenecks for fuel cell technology is the durability that needs to be improved. In order for marine vessels to implement hydrogen propulsion, the degradation need to be further understood and mitigated. The purpose of this thesis was to assess the most significant degradation mechanisms for marine applications and to build a model to evaluate the lifetime depending on load profiles. The scope of the thesis was to include PEMFCs since they have the highest power density and are closest to commercialisation for transport applications. A literature review was conducted to assess the most important degradation mechanisms and operating conditions that limits the lifetime, which concluded in start/stop cycling and load cycling. These conditions deteriorate the membrane conductivity and the electrochemical surface area. An empirical model based on experimental data from the literature was conducted to find relationships for conductivity and ECSA as function of start/stop cycling and load cycling, respectively. A Comsol model was established to evaluate performance reduction with degraded parameters. Two different load cycles were interpreted as number of start/stop cycles and load cycles in order to simulate the degradation. The output was polarization curves as function of operating years. Each case was operated until a performance reduction of 20 % was obtained at the current density of 0.6 A/cm2. Both load profiles were analysed with different operation strategies to compare the resulting lifetime. The first load curve was divided into Case 1a and Case 1b where start/stop cycles and load cycles were altered. The results showed that the lifetime in operation hours was more than three-folded in Case 1b when the number of start/stop cycles and load cycles was reduced. Case 2 was divided into three operating strategies. For comparison with Case 2a, the number of start/stop cycles per day in Case 2b was increased by a factor of 4. The result was that the lifetime declined from 6 to 4 years. Furthermore, Case 2c evaluated the lifetime if the number of load cycles per day decreased by a factor of 4, all else being equal to Case 2a. The outcome was an increment in lifetime from 6 to 11 years, with a total of 32 032 hours of operation. This lifetime can be compared to commercialised products from Ballard and Powercell with lifetimes of 30 000 and 20 000 operating hours, respectively. Conclusively, the simulations showed that both start/stop cycling and load cycling deteriorates the fuel cell performance. Load cycling is the operating condition that cause the most severe degradation. Moreover, the modelled lifetime of 32 032 hours indicates that the empirical model in combination with the Comsol model generate realistic lifetimes. Finally, since load cycling had the most vital impact on the lifetime, one of the topics for future research would be to distinguish different types of load cycles and connect to separate degradation outcomes. Since the model was on fuel cell level, future work could also include systems effects such as ripple current or distributions within fuel cell stacks.

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Para, Eric George. "Coastal Sediment and Fish Biosolids Remediation Using a Microbial Fuel Cell." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/ParaEG2006.pdf.

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Nguyen, Thi Hong Minh, and Van Hanh Vu. "Bioethanol production from marine algae biomass: prospect and troubles." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-99282.

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The increase of petroleum cost as well as global warming and climate change result in investigation to discover new renewable energy resources. Bioenergy is one of the most important sources that is concerning the scientists and industrial sector. Although bioethanol had to be known as one of the most important renewable energy sources in order to reduce greenhouse gases and global warming, there is a limited number of publications reporting on them. In this review, a brief overview is offered about bioethanol production from algae. It can be given a deeper insight in dificulties and promising potential of bioethanol from algae
Sự gia tăng giá nhiên liệu hóa thạch cùng với cảnh báo toàn cầu về biến đổi khí hậu hướng đến việc nghiên cứu tìm ra những nguồn năng lượng có thể tái tạo. Năng lượng sinh học là một trong những nguồn quan trọng được các nhà khoa học và doanh nghiệp quan tâm. Mặc dù ethanol sinh học đã được biết đến như là một trong những dạng năng lượng tái tạo quan trọng nhất để giảm thiểu các khí nhà kính và cảnh báo toàn cầu, nhưng chỉ có một số ít bài báo về nó. Trong bài tổng quan này, chúng tôi giới thiệu vắn tắt việc sản xuất ethanol sinh học từ tảo. Nó đưa ra cái nhìn sâu hơn về những khó khăn và tiềm năng hứa hẹn của sản xuất ethanol sinh học từ tảo

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Bassam, Ameen. "Use of voyage simulation to investigate hybrid fuel cell systems for marine propulsion." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/412705/.

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The design of green ships has received significant attention with the goal of reducing the negative environmental impacts of shipping and to comply with the more stringent environmental regulations. Therefore, in 2009 the International Maritime Organisation (IMO) published the Energy Efficiency Design Index (EEDI) measures to be adopted by new ships to reduce the Greenhouse Gases (GHG). Hybrid electric power and propulsion is one of the EEDI measures and fuel cell technologies are considered as a candidate to be used due to their high efficiency, lower emissions, lower maintenance, and quiet operation. This project aims to investigate the use of hybrid propulsion systems for marine propulsion which utilise fuel cells as a main source of power and the effect of energy management on the performance of these systems through voyage simulation. In order to assess the effectiveness of fuel cells as a source of power for ship propulsion systems, the development of a time-domain three degree of freedom total ship system simulator using MATLAB/Simulink is completed. Different components of the ship, including its propulsion system, and the ship's interaction with the surrounding environment are mathematically modelled. Considered power sources in the thesis include conventional two and four-stroke diesel engines, fuel cells and batteries to enable the comparison between conventional and hybrid fuel cell power trains. The verification and validation of the developed ship system simulator are also conducted using numerical, experimental and real ship operational data. The thesis demonstrates the use of the developed total ship system simulator in proposing a hybrid fuel cell/battery propulsion system for a domestic ferry. The results indicate that the hybrid fuel cell system has less weight and requires less space than the conventional diesel system. However, the hybrid fuel cell system's associated costs are still higher than diesel propulsion system. For hybrid fuel cell systems, the design of a suitable energy management strategy is essential in order to handle properly the required power split between the fuel cell and the battery systems. Therefore, the developed ship system simulator is also used to study and compare the most common energy management strategies. An improvement to the classical proportional-integral controller based strategy is presented in this thesis. This improvement results in minimizing the fuel cell operational stress and hydrogen consumption. Alongside this work, a novel multi-scheme energy management strategy with a main objective of reducing the total consumed energy is also developed for the world's first fuel cell passenger ship.

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Lebo, Stephen J. Scott Robert M. "Lease vs. Purchase analysis of alternative fuel vehicles in the United States Marine Corps." Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Dec/09Dec%5FLebo_Scott.pdf.

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Thesis (M.S. in Management)--Naval Postgraduate School, December 2009.
Thesis Advisor: Gates, William R. Second Reader: Summers, Donald E. "December 2009." Description based on title screen as viewed on January 26, 2010. Author(s) subject terms: lease, purchase, Alternative-fuel Vehicle (AFV), incremental costs, salvage values, General Services Administration (GSA), United States Marine Corps (USMC), light-duty vehicle. Includes bibliographical references (p. 61-63). Also available in print.

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Scott, Robert M. "Lease vs. Purchase analysis of alternative fuel vehicles in the United States Marine Corps." Thesis, Monterey, California. Naval Postgraduate School, 2009. http://hdl.handle.net/10945/4505.

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Approved for public release, distribution unlimited
e what the USMC's optimal acquisition decision should be (lease or purchase) given potential changes in purchasing patterns over time. This analysis will afford decision makers the ability to make strategic financial decisions based on anticipated changes in the size of the USMC's Garrison Mobile Equipment fleet, as well as anticipated changes in market conditions regarding vehicle purchase prices, incremental costs, and salvage values. To answer these questions, this thesis will analyze historical data (2004 to 2009) for the largest populations of AFVs in the light-duty category and then apply a model that will compare the two alternatives based on their relative net present values. An aggregated view of several different light-duty AFV categories will then identify whether leasing or purchasing would be the most preferred.

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Schendler, Phillip J. "Costs and benefits of using fuel cells for stationary power generation at Marine Corps Logistics Base Barstow Maintenance Center." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Dec%5FSchendler.pdf.

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Thesis (M.S. in Management)--Naval Postgraduate School, December 2002.
Thesis advisor(s): William R. Gates, David R. Henderson. Includes bibliographical references (p. 73-76). Also available online.

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21

Landet, Ragnar Dystvold. "PM emissions and NOx-reduction due to water in fuel emulsions in marine diesel engines." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11590.

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The goal of this M.Sc. thesis has been to study the NOx-reduction measure: water in fuel emulsion. There has been done a literature study to look into the function, system components and effect upon NOx reduction, specific fuel oil consumption and other emissions. The operational aspects of water in fuel emulsion have been looked into. It has been found that running on water in fuel emulsion does not have many operational problems. However there is a need for having a "fail safe" system that can shut down the water supply if the engine has a failure and if the dosage system fails to give the right amount of water. This has to be done in order to prevent the separation of water and fuel that will happen if the emulsion is stationary for too long. The possibility of using the engine simulation program GT-Power in order to examine NOx emissions and specific fuel oil consumption has been investigated. For this there has been used a Rolls Royce KRG-6 engine model. The results of these investigations are a number of modifications that needs to be done to the engine model in order to achieve reasonable results. It has also been found that there is a need for more specific engine data if one wants to achieve good results. However reasonable results for relative NOx- reduction have been found. This supports the idea of GT-Power being suitable for this kind of simulations. Engine runs in the lab at MARINTEK, running the KR-3 engine on white diesel have been performed and the results from these test are that the emissions of NOx is reduced, but not nearly as much as expected. Particulate matter measurements showed a large increase in the size distribution around diameters of 20nm. This is the size of particles in the nucleation mode. The result for filter smoke number is a very large reduction; this supports the theory that soot in the exhaust gas is reduced when introducing water to the combustion chamber. However looking at the particle size distribution does not support this theory. These measurements show that the particle number within the range of accumulation mode particles (80nm) is about the same. This raises a question about how reliable the smoke number is when determining the contents of soot in the exhaust gas.

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Tse, Lawrence K. C. "Detailed study of integrating solid oxide fuel cell-gas turbine hybrid system for marine applications." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/11753.

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This thesis presents the computational evaluation of the system configuration and optimisation of a recuperated SOFC-GT system with combined heating cooling and power (CCHP) or trigeneration for marine applications. A comprehensive configuration analysis of a SOFC-GT system is needed to characterise the performance of different system configuration across a range of operating conditions, in order to choose a design point with optimum performance, and carry out off-design analysis. Then, a sensitivity analysis of the effects of changing the components, ambient temperature and air utilisation and fuel utilisation within a safe operating range is carried out. The fuel cell module within the Matlab model simulates methane reforming reactions; and fuel cell electrochemical reaction with the use of Voltage-current (V-i) curve from Siemens Westinghouse experimental SOFC data. The trigeneration model was calculated based on the outlet temperature of the SOFC-GT system as well as the inlet flow rates into the system. A number of system configurations of air conditioning system with conventional Heating Ventilation and Air Conditioning (HVAC) coils, absorption chiller and desiccant wheel are integrated with the existing SOFC-GT system, in order to extract waste heat from the SOFC-GT system exhaust for heating and cooling purposes for the ship. It is found that the recuperated SOFC-GT system is the optimum system configuration. The system efficiency and specific power are both high, when the compressor is operating at 4 bar pressure, with 1250K of turbine entry temperature, fuel cell operating at 1273K, current density at 300mA/cm2, corresponding to 0.704V of fuel cell voltage. When the compressor and turbine designed by the National Technical University of Athens are used in the system with power turbine, the overall thermal efficiency at design point is 59.7%. The hybrid system can operate from 31% to 100% of design point power, when running the system in off-design with air utilisation between 0.1 and 0.25. The choice of compressor and turbine will lead to variations in operating range for off-design. The operating range of the system is bounded by a safety range of air utilisation, which has major effect on the efficiency, total specific power, and gas turbine power split; and fuel utilisation, which is negligible effect on system performance criteria. The ambient condition changes have little effects on the total specific power. However, at higher temperature, the operating line moves closer but not near to the surge line. By using variable geometry compressor and turbine, the operating line can be moved even further away from surge, and this is useful in maintaining system stability when operating in tropical areas. There are also additional benefits of extending the operating range and increasing overall system efficiency, by a maximum of 3% and 1.5% respectively. The Trigeneration model results show that the double effect absorption cooler is the most energy efficient heat recovery unit to be integrated with the SOFC-GT system. When there are fewer occupants in the ship, running fewer HVAC units than designed can reduce the volume of hot air from outdoor, hence requiring less electrical energy for cooling and dehumidification, increasing overall system efficiency. When the number of HVAC units in operation is reduced from 7 to 3 in Ship 1, the maximum number of people allowed indoors (with 18 litres/s per person of air flow rate to ensure freshness of air) is reduced from 138 to 59 persons, but the indoor heat needed to be removed is reduced from 321kW to 242kW. The absorption chiller removes nearly 50% of the heat from the indoor environment when 3 HVAC units are in operations. Hence, the net overall efficiency of the 250kWe Combined Heating, Cooling and Power system is increased from 43.2% for 7 units to 64% for 3 units. Moreover, the net electric power (after air conditioning) available for base load is increased from 74kW to 116kW.

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Jakobsson, Niklas, and Peter Rydholm. "Ecodriving - hot eller möjlighet : En kvalitativ studie om intresset för ecodriving till sjöss." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-64025.

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Det finns ekonomiska, säkerhetsmässiga och miljömässiga vinster att göra genom att tillämpa ecodriving. Tidigare forskning pekar på att transportslagen bilar, tåg och flyg har gjort stora besparingar i ekonomiskt och miljömässigt hänseende, men hur ser det ut inom sjöfarten? Med denna frågeställning som bakgrund är syftet med studien att studera intresset för ecodriving bland svenska rederier och svenska myndigheter med en fartygsflotta. Dataunderlaget för studien utgörs av material från kvalitativa intervjuer med personer i exekutiv position. Resultatet av studien visar på att de flesta verksamheterna står i startgroparna eller redan arbetar utifrån en eller flera aktivt valda metoder för ecodriving. Resultatet visar också att det finns en blandning av förutsättningar och uppfattningar om vad ecodriving är och vad det kan bli inom sjöfarten. När frågor om automatisering i samband med ecodriving behandlas är resultatet tvetydigt.
There are economical, safetylike and environmental benefits of applying eco-driving. Previous research has shown that cars, trains and aviation have made significant savings economically and environmentaly speaking, but how does that transcend into the maritime business? With this question as a background, the aim with this thesis is to examine the interest of ecodriving among Swedish shipowners and authorities. The data in this thesis is derived from qualitative interviews with employees in executive land-based positions. The result shows that several of the shipowners and authorities are in the starting pits or are already conducting one or more eco-driving methods in their operations. The result also shows that there is a variety of prerequisites and perceptions of what eco-driving is and what is could become in the future among the respondents. When questions about automatization in relation to eco-driving are brought up, the result is ambiguous.

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Viado, Harold A. "An optimization model for sea-based supply of bulk fuel for a deployed marine expeditionary unit." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA365435.

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Skahen, Stephen "Jack", Michael Brookhart, Michael Boyett, Steven Benner, josue Kure, and Jason Maier. "Exploring the reduction of fuel consumption for ship-to-shore connectors of the Marine Expeditionary Brigade." Thesis, Monterey, California: Naval Postgraduate School, 2013. http://hdl.handle.net/10945/39005.

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Approved for public release; distribution is unlimited.
At the beginning of the 21st century, the United States Marine Corps (USMC) took a leading role in the war on terror. The traditionally amphibious force deployed massive amounts of troops and supplies in two major land wars of occupation. Now, as the USMC winds down its participation in the conflicts, it must seek to return to its roots as a primarily amphibious force without the benefits of a land-based operation. Tomorrows battles will likely begin from the littorals in and around the coastal regions of the developing world. The Marine Corps must prepare itself to operate without the benefit of readily available fossil fuels and supplies shipped in by trucks or home-based supply lines. As demonstrated in the current conflicts, the threats of IEDs and the expenses of obtaining fossils fuels make it imperative that the Marine Expeditionary Brigade (MEB) of the future must be able to bring its supplies with them or have them delivered by readily available and close-by alternate means. This research will evaluate the current landing doctrine of a notional MEB and its associated ship-to-shore connectors. It will analyze potential changes in doctrine with the goal of reducing energy footprint while maintaining mission effectiveness.

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Olander, Petra. "Tribology for Greener Combustion Engines : Scuffing in Marine Engines and a Lubricating Boric Acid Fuel Additive." Doctoral thesis, Uppsala universitet, Tillämpad materialvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-333430.

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This thesis aims at increased knowledge in two fields of tribological research; both related to making currently used combustion engines greener. The first field regards the possibilities of using a boric acid fuel additive to increase fuel efficiency. The second field is about the severe wear phenomenon scuffing, which can become problematic when cargo ships are operated on low-sulphur fuel to reduce sulphuric emissions. Tribological tests were developed and performed to simulate the applications. Advanced surface analysis was performed to understand changes occurring on the outermost surface of sliding components, which affect friction and wear. Samples from engines were studied to verify the relation between the lab tests and the applications. In the case of boric acid, the coefficient of friction was below 0.02 for large parts of the tests, but varied with test parameters. The corresponding reduction in friction was up to 78% compared with tests without the additive. As an attempt to assess if the substantial fuel savings found in field tests with passenger cars (6%) can be explained by friction reduction in boundary and mixed lubricated parts of the piston assembly, assumptions were presented that would lead to fuel savings close to these 6%. Boric acid was detected on surfaces after the tests, and the tribofilm appearance depended on test parameters. The tribofilms were shown to be affected by storage time and test temperature; a finding that is vital for future studies. In the case of scuffing, mechanisms were studied and accumulation of wear debris had a significant role on scuffing initiation in the lab scale scuffing tests. Regarding the possibility to test materials scuffing resistance, there was a large scatter in the results, and thereby difficult to draw conclusions. Two new piston ring materials were identified to perform somewhat better than the currently used. In conclusion, findings that could facilitate immediate improvement of fuel efficiency of today’s combustion engine vehicles as well as findings that strengthen available hypotheses on scuffing mechanisms are presented. The latter offers improved understanding of scuffing and thereby give possibilities to counteract the higher risk associated with operation on cleaner fuel.

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Ryste, Julianne Mari. "Screening LCA of GHG emissions related to LNG as ship fuel." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18643.

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In view of the increasingly popular climate change debate worldwide, maritime transport is under pressure to create sustainable solutions for a cleaner future.One of these solutions is using liquefied natural gas (LNG) as ship fuel. LNG has a higher hydrogen-to-carbon ratio compared with oil-based fuels, which results in lower specific CO2 emissions (kg CO2/kg fuel). Other benefits of LNG are the total elimination of SOx emissions and particulate matter, and 85-90 % reductions in NOx emissions. DNV has estimated a net global warming benefit of 15 % with the use of LNG. However there is still a need to map the greenhouse gas emissions throughout the life cycle of LNG. This thesis is a Screening Life Cycle Assessment of LNG as fuel, with the main objective to carry out a life cycle analysis of the process “Bunkering of LNG”. Screening is a simplified LCA which aims at identifying the important parts of a life cycle, or so-called hotspots. Bunkering of LNG and the bunkering facility have been chosen as the hotspots in this analysis for their uniqueness. The processes related to bunkering have not been analysed at this level of detail in published literature. The LCA software GaBi Educational has been used to implement the bunkering model and analyse the life cycle inventory results. Processes related to energy use, manufacturing and direct emissions were included in the GaBi model. The CML 2001 method was used to assess the Global Warming Potential (GWP). This is the main characterisation factor of the environmental issue climate change, which was in focus in this analysis.The impact assessment showed that emissions related to manufacturing are the greatest contributors to the GWP, with a total GWP of 75 917 [kg CO2-Equiv]. Energy use contributes the least, with only 0,36 ‰ of the total impact, which is considered negligible. Direct emissions stand for 7 777 [kg CO2-Equiv] and is the only area of the bunkering life cycle where emissions can be considerably reduced. In fact, all direct emissions can be omitted by the use of BOG recovery strategies, such as vapour return. The conclusion drawn is that the emissions associated with bunkering of LNG is perhaps not the main issue. A more pressing issue at the moment is the low fuelling possibilities for LNG. If LNG is to become the fuel of the future, fuelling must be made more accessible and available.

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James, Kris. "The design and performance of a civil marine reactor with regard to the thermal performance of the fuel." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/18067/.

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There is a concerted world wide effort to limit greenhouse gases into the atmosphere. Civil shipping accounts for a 3 % proportion of greenhouse gas emissions and to combat this problem, nuclear power is proposed as an alternative energy source. This thesis set out to evaluate the use of a civil marine nuclear reactor for commercial shipping purposes. A review was carried out to determine past uses of civil marine nuclear reactors to assist specification of the criteria for a civil ship reactor e.g. reactor type, operating conditions. The refuelling period of such ships was understood as an issue for commercial success and so having fuel in the reactor for periods of 15 years was determined to be a key goal, as well as keeping the fissile enrichment of the fuel low. Computational simulation of the thermo-mechanical performance on fuel rods under expected operating conditions for a civil marine reactor were conducted. Higher thermal efficiency in the fuel rods was determined to be key in achieving long refuelling periods. Fabrication of simulant fuel cermets was undertaken with spark plasma sintering to produce simulant cermet fuel pellets with improved thermal conductivity and was evaluated to be an efficient cermet production route. This was achieved with YSZ as a simulant for UO2 fuel, with metallic Mo and W to produce stable cermets at varying metallic loading. The thermal conductivity values were found to increase by a factor of 2-3 with up to 30 % metallic loading. The final aspect of this thesis focused on finite element simulation, studying the shape of metallic loading inside a cermet to determine a suitable layout to provide the greatest thermal transfer with several candidate geometries determined to be appropriately suitable.

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Stacey, Bruce M. "The chronic effect of no. 2 fuel oil on the population dynamics of Harpacticoid copepods in experimental marine mesocosms /." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63374.

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Marin, Radovan [Verfasser]. "The influence of engine and vehicle constructions to fuel consumption and air pollution / Radovan Marin." München : GRIN Verlag, 2020. http://d-nb.info/1209545497/34.

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Du, Toit Maria Hendrina. "Introducing advanced thorium-based fuel cycles in SA : an evolutionary approach / Maria Hendrina (Marina) du Toit." Thesis, North-West University, 2013. http://hdl.handle.net/10394/8734.

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Past experience in several thorium fuelled research- and power reactors provides the basis and history of thorium. The material properties, fertile- and fissile isotope properties as well as the decay chain of thorium are discussed for purposes of evaluating thorium as a source of fuel. The different thorium-based fuel designs for PWR cores are discussed and resulting difficulties and solutions are outlined. The different options for each strategy are compared in terms of advantages and disadvantages. A process of elimination selects the best option for each strategy, which results in a combination of mitigation and optimisation strategies to be implemented at the starting point of the roadmap. Certain countries have made significant progress with regards to the thorium-based fuel cycle (e.g. India and Norway) and nuclear technology in general (South Korea). Each country is introduced with a summary of their approach and policy. The current context of nuclear technology and the nuclear fuel cycle in SA is given. The identified lessons and policies are applied to the South African context, which results in different goals aimed at achieving a thorium-based fuel cycle in the future. These goals form an integral part of the roadmap to implement thorium-based fuels in SA. The prices of uranium and thorium are discussed. This chapter focuses on the economic advantages of thorium-based fuel cycles, especially the fuel cycle cost and the refuelling outage costs. Thorium-based fuels can extend the refuelling cycles, which in turn reduce the fuel requirements and the spent fuel for disposal, as well as the reactor downtime for refuelling. The results show that both (Th/U)O2 and (Th/Pu)O2 present economic benefits over traditional uranium fuel cycles. The total savings were calculated by adding the fuel cycle savings and the refuelling outage saving. (Th/U)O2-fuel proved to be the most economical and Eskom could save up to 49 billion rand in 60 years. Based on the research and results obtained, a systematic strategic thorium-based fuel implementation roadmap is developed. Economic-, strategic- and historical aspects direct the roadmap. The advantages of thorium-based fuels are summarised and form the initiative to implement thorium-based fuels in SA. A timeline (which forms the basis of the roadmap) is developed. The roadmap consists of three different phases. Phase 1 starts in 2013 and extends to 2030. Phase 2 starts in 2031 up to 2044 and Phase 3 from 2045 to 2060. Each phase is discussed with regard to construction, implementation and research activities. This roadmap will progress and advance to future technologies, corresponding to the evolutionary approach.
Thesis (MIng (Nuclear Engineering))--North-West University, Potchefstroom Campus, 2013

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Hillberg, Torbjörn, and Emil Holmberg. "Metanol som marint bränsle : Alkohol som en lösning, inte ett problem." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-34103.

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Sedan industrialismens start har människan påverkat klimatbalansen genom förbränning av fossila bränslen. Rökgasemissionerna förorsakade av internationell sjöfart kan inte tillskrivas någon särskild nations ansvar på grund av dess globala och komplicerade verksamhet. FN:s sjöfartsorgan IMO har således åtagit sig ansvaret att minska sjöfartens miljöpåverkan. Införandet av nya miljömål har resulterat i strängare globala och nationella regler som tvingar sjöfartsnäringen till omfattande anpassningar under kort tid. Som lösning för att uppfylla kommande krav gällande rökgasemissioner har flertalet alternativa bränslen diskuterats. Drift på metanol medför låga rökgasemissioner och anses därav ha potential till att bli ett hållbart bränsle inom sjöfarten. Studiens syfte har varit att undersöka vad rederier, maskintillverkare och klassningssällskap anser om metanol som ett alternativt bränsle. Inledningsvis genomfördes en litteraturstudiedel som sedan låg till grund under utformandet av intervjufrågorna. Resultatet visar att metanol anses ha stor potential i jämförelse med andra alternativa bränsle. Då metanol kan produceras från överskottsenergi och transport kan ske med befintlig infrastruktur betraktas det både miljövänligt och ekonomiskt försvarbart. Likväl medför det kraftigt varierande metanolpriset att rederier hämmas att satsa på utvecklingen som krävs för att realisera metanoldrift av fartyg.
Since the start of industrialization humans have affected the climate balance by burning fossil fuels. Exhaust gas emissions caused by the international shipping cannot be attributed to any particular nation because of its global and complex business. The International Maritime Organisation has therefore undertaken the responsibility to reduce the environmental impact of shipping. The introduction of new environmental goals has resulted in stricter global and national regulations that force the shipping industry to make significant adjustments in a short period of time. As a solution to meet future requirements for exhaust gas emissions several alternative fuels have been discussed. Operating vessels on methanol results in low exhaust gas emissions and is therefore considered to have the potential to become a sustainable fuel for the shipping industry. The aim of this study was to investigate what shipping companies, machine manufacturers and classification societies considers about methanol as an alternative fuel. Initially, a literature study was implemented which formed the basis of the interview questions. The result shows that methanol is considered to have great potential compared with other alternative fuels. Since methanol can be produced from excess energy and transportation can be done with existing infrastructure methanol is considered both environmentally friendly and economically viable. Nevertheless, the highly fluctuating methanol price can causes shipping companies to hesitate in the financing of developments that is necessary for the realization of methanol operation on board vessels.

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Holmström, Johnny. "GOVERNOR ELECTRONICS FOR DIESEL ENGINES : High availability platform for real-time control and advanced fuel efficiency algorithms." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-20282.

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Fossil fuel is a rare commodity and the combustion of this fuel results in negative environmental effects. This paper evaluates and validates the electronics needed to run intelligent algorithms to lower the fuel consumption for commercial vessels. This is done by integrating advanced fuel saving functions into an electronic device that controls the fuel injection of large diesel engines, as known as a diesel engine governor. The control system is classified as a safety critical system. This means that the electronics needs to be designed for fail safe operation. To allow for future research and development, the platform needs flexibility in respect to hardware reconfiguration and software changes, i.e. this is the basis for a system that allows for hardware-software co-design. For efficient installation and easy commissioning, the system shall allow for auto-calibration combined with programmable jumper selections to attain a cost effective solution. The computation of the fuel saving algorithm require accurate data to build a model of the vessels motions. This is achieved by integrating state of the art sensors and a multitude of communication interfaces. Among other things gyroscopes contra accelerometers where evaluated to find the best solution in respect to cost and performance. This design replace the current product DEGO III. The new product requires the same functionality and shall allow for more functions. Focus has been spent on communication, methods of accruing sensor data and more computation speed. In creating a new generation of a product there are tasks like selecting components, questions pertaining to layout of the printed circuit board and an evaluation of supply chains. The manufacturing aspects are considered to rationalize production and testing.
Fossila bränslen är en dyrbar råvara och förbränningen av detta bränsle leder till negativa miljöeffekter. Detta papper utvärderar och verifierar elektroniken som behövs för att beräkna intelligenta algoritmer som minskar bränsle konsumtionen för kommersiella fartyg. Detta görs genom att sammanfoga avancerade funktioner i en och samma elektroniska enhet som kontrollerar bränsle insprutningen på stora diesel motorer, denna elektronik är känd som en varvtals regulator. Kontroll systemet är klassificerat som ett säkerhetskritiskt system. Detta betyder att elektroniken måste utformas för att vara felsäker. För att tillåta framtida forskning och utveckling behöver plattformen vara flexibel. Den ska tillåta konfiguration av hårdvara och mjukvara ändringar. Samverkan mellan hårdvara och mjukvara. För effektiv installation samt drifttagning, måste systemet vara automat-kalibrerande och utrustat med programmerbara byglingar som möjliggör en kostnadseffektiv lösning. Beräkningen av bränsle optimeringen behöver en detaljerad modell av fartygets rörelse. Detta möjliggörs genom att integrera moderna sensorer och en mängd olika kommunikationsmedier. Bland annat så utvärderades gyroskop kontra accelerometrar för att hitta den bästa lösningen i förhållande till kostnad och kvalitet. Denna design ersätter den nuvarande produkten DEGO III. Den nya produkten behöver samma funktionalitet samt en mängd nya funktioner. Fokus har varit kommunikation, metoder för att samla sensordata och ökad beräknings kraft. När en ny generation av en produkt ska utvecklas finns uppgifter så som att välja komponenter, frågor gällande mönsterkorts layout och en utvärdering av leverantörs källor. Tillverkningen av prototypen inkluderar utvärdering av produktions metoder för att effektivisera tillverkning och verifiering.

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Battistelli, Arrigo. "Investigation of a Concept for Simultaneous Reliquefaction of Boil-Off-Gas and Vaporization of LNG for Marine Atmospheric LNG Fuel Tanks." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for elkraftteknikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25738.

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The aim of this thesis is to design and optimize a heat pump process to reliquefy Boil-Off-Gas from Liquefied Natural Gas (LNG) cryogenic tanks, and simulataneously vaporize LNG at high pressure.The process is meant for use onboard LNG fuelled ship different from LNG carriers, equipped with LNG fuel tanks at atmospheric pressure and 2-strokes engines with high pressure gas injection, which is considered the most efficient propulsion arrangement for medium-large vessels.The studyis based on a patented concept from the norwegian companyLNG New Technlogies, within the thesis this concept is evolved to a more complex process layout, its distinctive features are low temperature suction of the heat pump refrigerant compressor, absence of heat discharge to the environment and condensation of the Boil-Off-Gas via recirculation of subcooled LNG. Four different operating scenarios of the process are simulated with the commercial software HYSYS® , the results of the simulations are presented in the form of case studies, sensitivity analyses, thermodynamic diagrams and tables, and analized in detail. Anumber of modifications to the selected layout are evaluated, e.g. Boil-Off-Gas feed to the Auxiliaryengine and compressor intercooling. Based on the simulation results a preliminary selection ofthe process equipment is outlined, with focus on the refrigerant compressor.The results prove that the proposed heat pump process can effectively refrigerate the LNG tank if the ship is operating in the normal mode or at half of the main engine load, however at lower engine loads, especially when the main engine is shut down, the system can not produce the required refrigeration effect. In this scenario the excess Boil-Off-Gas would be fed to the Auxiliary engines, or in the worst case burnt in Gas Combustion Units. The heat pump efficiency for the normal operation is 2-3 times higher than for commercial on-board Boil-Off-Gas reliquefaction processes, but the maximumreliquefaction capacity is intrinsically lower. The operating parameters of the compressor suggest the use of a reciprocating oil-free compressor with cryogenic material specifications, this is considered the most non-conventional and costly unit of the process.

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Weirich, Timothy Douglas. "Evaluating the Potential for Atmospheric Corrosion of 304 Stainless Steel Used for Dry Storage of Spent Nuclear Fuel." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1557098372186951.

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Soufi, Jihène. "Traitement des gaz d’échappement des groupes électrogènes alimentés par des gasoils, fuels marines ou bio-huiles : élimination des HAP en présence ou non de SOx." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1120.

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Andrén, Filip, and Olav Borgström. "Common Rail - En bränslebesparingsstudie : – En utvärdering av ett nyinstallerat bränsleinsprutningssystem på isbrytaren Ymer." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-50558.

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Följande studie är gjord på uppdrag av Sjöfartsverket. I studien undersöktes hur en installation av ett Common Rail-system ombord på isbrytaren Ymer påverkat bränsleförbrukningen samt utsläppen av kväveoxider. Rådata som loggats ombord på Ymer har analyserat och bearbetat. Material och information från tillverkare, besättning samt teknisk chef på Sjöfartsverket, Albert Hagander har använts under studien. Tillsammans med uppmätta mätdata och tidigare gjord litteraturstudie stöds resultaten i studien. Det är ingen slump att system av Common Rail-typ redan är tillämpat inom de flesta branscher så som transport, personbilsindustri och jordbruk. Huvudsyftet med Common Rail är att minska bränsleåtgången samt minska utsläppen genom en renare och mer effektiv förbränning av bränslet. Huvudsakligen undersöktes hur det nyinstallerade systemet påverkat bränsleförbrukningen och hur bränslebesparingen varierar med belastningen av maskinen. Vidare granskades hur utsläppen av kvävedioxider påverkats efter installationen. Problematiken med ökad NOx-produktion till följd av en högre förbränningstemperatur som Common Railsystemet medför diskuteras i rapporten. De resultat vi kommit fram till att en bränslebesparing kan göras ombord på Ymer genom att ersätta det gamla bränslesystemet med ett bränslesystem av Common Rail-typ. Vidare har installationen medfört andra förbättringar så som fartygsmaskinens reaktion på de många lastväxlingar som förekommer under isbrytning.
The following study has been carried out on behalf of Sjöfartsverket. The study examines how the installation of a common rail system on board the icebreaker Ymer affected fuel consumption and emissions of nitrogen oxides. The raw data logged on board Ymer was analyzed and processed. Materials and information from manufacturers, crew and the technical manager at the Swedish Maritime Administration, Albert Hagander have been used during the study. Together with measured data and previously made research study the findings of the study are supported. It is no coincidence that the system of the common rail type is already applied in most industries such as transport, car industry and agriculture. The main purpose of the Common Rail is to reduce fuel consumption and reduce emissions through cleaner and more efficient combustion of the fuel. We primarily examined how the newly installed system affected fuel consumption and the fuel savings will vary with the load of the machine. Furthermore, we examined how emissions of nitrogen oxides were affected after installation. The problem of increased NOx production due to a higher combustion temperature as the common rail system entails are discussed in the report. The result that was concluded was that fuel savings can be made on board Ymer by replacing the old fuel system with a common rail fuel type. Furthermore, the installation has brought other improvements such as ship machine's reaction to the many load changes that occur during icebreaking.

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Junior, Antonio Fernandez Prada. "Avaliação da qualidade de ignição para utilização de petróleos pesados e asfálticos como combustíveis marítimos." Universidade do Estado do Rio de Janeiro, 2007. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7383.

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As correntes pesadas do refino de petróleo podem ser utilizadas para a produção de óleos combustíveis para uso industrial ou marítimo, sendo esse último conhecido como óleo bunker. Para tal, é necessária a diluição dessas correntes pesadas com frações de refino mais leves para ajuste da viscosidade. Enquanto o uso industrial do óleo combustível vem sendo significativamente reduzido em função de restrições ambientais, o mercado de óleo bunker apresenta crescimento importante face a expansão do comércio marítimo mundial. No Brasil, há um aumento da produção de petróleos pesados, extrapesados e asfálticos, que exigem complexos esquemas de refino para a sua conversão em frações mais leves. Dessa forma, ocorre uma redução da quantidade de correntes disponíveis para a produção de bunker, além da variação da qualidade das correntes usadas na sua formulação. Esta dissertação avalia a utilização de petróleos pesados e asfálticos na produção de bunker, sem a necessidade do processamento tradicional em refinarias de petróleo. A comparação da qualidade de ignição e de combustão da nova formulação deste produto com o combustível marítimo preparado a partir de correntes residuais é realizada por duas metodologias diferentes. Após a realização de um pré-tratamento, a mistura formulada a partir dos cortes dos petróleos apresenta melhor desempenho que os combustíveis formulados com as correntes residuais. Além disso, este trabalho compara o efeito de diferentes diluentes e a contribuição da corrente pesada utilizada na qualidade de ignição e de combustão do produto
Heavy streams from crude oil refining can be used to prepare fuel oils for industrial or maritime purposes, the latter known as bunker fuel. In order to prepare them, it is necessary to set viscosity to its appropriate value by dilution with lighter fractions from petroleum refining. While industrial usage of fuel oils is decreasing significantly due to environmental restrictions, the bunker fuel market shows an important increasing face to the growing in world maritime trading. Production of heavy, extra heavy and asphaltic crude oils in Brazil is rising and more complex refining process are required to convert them into lighter petroleum products. Because of that, the amount and the quality of available streams to prepare bunker fuel are decreasing. The present dissertation evaluates the feasibility of using heavy and asphaltic crude oils to prepare bunker fuel without traditional processing into petroleum refineries. The comparison of ignition and combustion quality considering the bunker fuel prepared from residual streams are made considering two different methodologies. After pre-treating the crude oils to prepare bunker fuels, that mixture shows a better ignition and combustion performance than those prepared with residual streams. Finally, this study compares the effect of different diluent streams and the heavy fraction contribution to products ignition and combustion quality

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Goel, Varun, and Sonja Wadelius. "Evaluation of transition towards zero emission commuter ferries : Comparative Analysis of Fuel-based and Battery-based Marine Propulsion System from financial and environmental perspectives." Thesis, KTH, Marina system, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302781.

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The purpose of this study is to compare the life-cycle cost and environmental impact of the existing fuel-based propulsion system, on public commuter ferries in Stockholm, with a battery based propulsion system. The study is divided into multiple layers. First, the operating characteristics of the route Line 80 within Stockholm’s waterborne public transportation (WPT) are collected, such as fuel consumption, propulsion power output, speed, voyage time and propulsion system configuration. Second, based on the energy demand of the route, important parameters related to the existing fuel-based propulsion system and the battery-based propulsion system are accounted for and modeled. Third, Life Cycle Assessment (LCA) and the cost assessment methods are applied to examine the effectiveness of the electrification of commuter ferries on a financial and environmental scale. With the help of the software GaBi 2020, GREET 2020, and other literature studies, the environmental impacts at the construction, use and end-of-life (EOL) phase are evaluated. There are in total 8 scenarios considered, 4 for the fuel-based and 4 for the battery-based propulsion system. The environmental performance of these 8 scenarios are discussed in terms of Globalwarmingpotential(GWP), Acidificationpotential(AP), Eutrophicationpotential(EP) and Photo-chemical ozone creation potential (POCP). Themostpollutingphaseistheusephase for all scenarios. Propulsion system powered by diesel (scenario 1) is considered as a reference for comparative analysis of 7 other scenarios. The best performing system is the one powered by batteries with the assumption of an electricity mix based on hydro, wind and nuclear power, which is scenario 7 and 8 with a net reduction of GWP by more than 98%, AP by 90%, EP by 96%, and the POCP by 96%. If we consider the current Swedish electricity mix (scenario 5 and 6), the decrease in GWP, AP, EP and POCP are 90%, 80%, 82% and 91% respectively. Alternative fuels also present promising results for GWP in comparison to diesel (with the origin of the feed-stock creating mostly negative impacts) but the contribution to other impact categories is significantly higher. With inputs from the industry and the environmental evaluation, the cost assessment compares the costs related to fuel-based and battery-based propulsion systems with different energy sources. For the battery-based system, 3 scenarios are modeled for two different types of Li-ion batteries. The vessels in the developed scenarios are charged more frequently than the existing electric vessel and the number of charging stations is varied. The costs that are included in the assessment are the initial capital cost, the cost for fuel/electricity, maintenance cost, end-of-life cost and emissions cost. When concerning all the cost categories, the battery-based system is more cost-efficient than a fuel-based system, if run on the Swedish electricity mix, due to the lower cost for electricity and emissions. The reduction of cost is more than 68% when comparing traditional diesel with battery-based systems, but the source of the electricity is very important.
Syftet med denna studie är att jämföra livscykelkostnaden och miljöpåverkan av de befintliga framdrivningssystemen på pendelbåtarna inom Stockholms kollektivtrafik, med batteridrivna system på motsvarande båtar. De befintliga framdrivningssystemen drivs av olika typer av diesel. Studien är uppdelad i flera steg. Först samlas driftsegenskaperna in, såsom bränsleförbrukning, framdrivningseffekt, hastighet, färdtidochframdrivningssystemetsuppbyggnad, etc, på linje 80, som är en del av Stockholms vattenburna kollektivtrafik. För det andra undersöks det befintliga framdrivningssystemet som drivs av diesel eller alternativa bränslen som RME eller HVO och fullt batteridrivna system utifrån energibehovet. För det tredje tillämpas metoderna för kostnadsanalys och livscykelanalys (LCA) för att undersöka hur elektrifieringen av pendelbåtar påverkar ekonomin och miljön. Med hjälp av programmet GaBi 2020, GREET 2020 och andra litteraturstudier utvärderas miljöpåverkan av faserna tillverkning, användning och avfallshantering. Det är totalt 8 scenarier som övervägs, 4 för bränslebaserade och 4 för batteri baserade framdrivningssystem. Hur bra dessa 8 scenarier presterar miljömässigt diskuteras i termer av växthuseffekt (GWP), försurning (AP), övergödning (EP) och marknära ozon (POCP). Den fasen med mest utsläpp, för alla scenarier, är användningsfasen. Framdrivningssystemet som drivs av diesel (scenario 1) används som referens att jämföra de övriga 7 scenarierna mot. Det system som presterar bästa är det som drivs av batterier, med antagandet att elmixen är baserad på vatten-, vind-och kärnkraft, detta motsvarar scenario 7 och 8 med en reduktion av GWP på mer än 98%, AP med 90%, EP med 96% och POCP med 96%. Om vi tittar på den aktuella svenska elmixen (scenario 5 och 6) så är minskningen av GWP, AP, EP och POCP 90%, 80%, 82% respektive 91%. Alternativa bränslen ger också lovande resultat för GWP jämfört med diesel (där råvarans ursprung skapar mest negativa effekter) men bidraget till andra påverkanskategorier är betydligt högre. Med input från företag och miljöutvärderingen kan kostnadsanalysen jämföra kostnaderna för bränslebaserade och batteri baserade framdrivningssystem med olika energikällor. Det batteri baserade systemet modelleras även på 3 utvecklade scenarier för 2 olika typer av batterier. Fartygen i de utvecklade scenarierna laddas oftare än det befintliga batteridrivna fartyget och antalet laddstationer varierar mellan scenarierna. De kostnader som inkluderas i analysen är de initiala kapitalkostnaderna, kostnaden för bränsle/el, underhållskostnader, avfallshanteringskostnader ochutsläppskostnader. Medallakostnaderinkluderadeiberäkningarna är batteri baserade system mer kostnadseffektiva än bränslebaserade system om de körs på svensk elmix, tack vare de lägre kostnaderna för el och utsläpp. Minskningen av den totala kostnaden är mer än 68% när man jämför traditionell diesel med batterisystem, men elens ursprung är mycket viktig.

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Marino, Michael G. [Verfasser], and Joachim [Akademischer Betreuer] Maier. "Anion exchange membranes for fuel cells and flow batteries : transport and stability of model systems / Michael G. Marino. Betreuer: Joachim Maier." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2015. http://d-nb.info/1074404912/34.

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Apraiz, Larrucea Itxaso. "Development and application of a proteomic approach to the assessment of pollution in the marine environment." Doctoral thesis, Stockholms universitet, Institutionen för biokemi och biofysik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-26150.

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Today, assessment of the health of coastal waters is recognized as being important for both the conservation of nature and well-being of humans. Anthropogenic pollution has been the focus of extensive research for some time and a variety of programs for the monitoring and assessment of environmental pollution have been developed. Determination of the levels of pollution in sensitive ‘sentinels’ such as mussels, allows monitoring of these levels in a given area over a prolonged period of time. Furthermore, the biological effects of pollution are reflected in a series of biomarkers, none of which provides a general picture of the sentinel’s state of health and all of which are individually specific for certain pollutants and influenced by both biotic and abiotic factors. In an attempt to improve biomonitoring of marine pollution, we have developed two proteomic approaches here. In the first portion of the thesis, a proteomic analysis was performed on peroxisomes isolated from mussels exposed either to one of three model anthropogenic pollutants, or two different types of crude oil, or from mussels exposed to the Prestige oil spill. Application of two-dimensional electrophoresis (2-DE) provided protein expression signatures (PES) for exposure to these different pollutants.Furthermore, several individual protein components of these PES could be putatively identified. In the second portion of this work, such analysis of subproteomes was developed further in order to improve the applicability of this approach to biomonitoring. A simple fractionation procedure in combination with liquid chromatography and 2-DE provided samples from mussels residing in different regions of a pollution gradient around the harbor of Gothenburg, as well as from mussels exposed to two types of fuel oil similar to that of the Prestige that were suitable for environmental proteomics. In addition, we constructed a model for this approach that can be cross-validated in the future and applied to assess sources of fuel oil pollution in connection with biomonitoring programs.

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Gutierrez, Saenz Juan. "Energy analysis and cost estimation of a potential On-shore Power Supply system in the Port of Gävle." Thesis, Högskolan i Gävle, Energisystem och byggnadsteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-30378.

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The Port of Gävle is one of the most important harbours in Sweden as far as size and freight capacity is concerned. Marine traffic is increasing greatly, thus environmental pollution as well as noise and vibrations are of major concern in port cities. Shore to ship power supply systems might be a feasible solution to curtail emissions because the Auxiliary Engines are instead shut down while the ship stays alongside the quay. The literature review shows they are reliable and very appealing in all respects, thereby contributing to sustainable development. Taking into account the kind of vessels that call at the Port of Gävle, a High Voltage Shore Connection is recommendable, in compliance with the International Standards. An own technical survey is developed to gather all the information, as well as personal interviews to collect first-hand data. Technical issues such as the synchronisation procedure and the ground system with regard to safety are briefly discussed. Due to the lack of data, calculations consist of average values: peak and average demand, and fuel consumption during a typical call. Considering updated energy prices for both electricity and fuel, results show that an on‑shore power supply system make energy costs decrease by 71% at berth in comparison with burning marine fuel, which is saved by around 4 tonnes per call. Additionally, up to 5126 tonnes of CO2 are avoided per year, among other pollutants. Shore‑side power has proven to be profitable and appealing to the Port of Gävle; however, vessels need to be retrofitted, which implies relatively high investments. Collaboration agreements and shipping companies’ willingness to undergo changes are key issues that still need to be solved.

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Stach, Robert [Verfasser]. "Mid infrared sensor technologies for environmental and occupational health and safety : advancement and application of infrared spectroscopies for monitoring fuel residues in marine ecosystems,and inhalable particles in mining scenarios / Robert Stach." Ulm : Universität Ulm, 2021. http://d-nb.info/1240314388/34.

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Edfors, Jonas, and Robin Bremberg. "Liquid Natural Gas : A study of the environmental impact of LNG in comparison to diesel." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-103569.

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Liquefied Natural Gases (LNG) has been an alternative fuel in the marine industry for several years, but lately, the amount of ships that have been powered by methane has increased a lot. Some of the reasons for this is because LNG does not contain any sulfur and releases less nitrogen oxides than traditional maritime fuels. In this essay, LNG will be compared to diesel from an environmental perspective with focus on CO2 emissions and its equivalents. International Maritime Organization (IMO) implemented Energy Efficiency Design Index (EEDI) requirements that adjusts how much CO2 is allowed in the exhaust gas per produced kilowatt-hour (kWh). However, these requirements will increase in intervals in the future, the next one is coming 2022 for specific ship types. The method that is used to compare the fuels is Mole-calculations for LNG as well as diesel, then calculate the amount of carbon dioxide (CO2) and its equivalents they release. The results show that under optimal conditions, LNG was the superior choice. However, the maritime industry might have a problem with the requirements that will be introduced to greenhouse gas (GHG) emissions in 2050.
Flytande Naturgas (LNG) har under flera år funnits som ett alternativt bränsle inom sjöfarten, men på senare tid så har skeppen som drivs av metan ökat markant. En anledning till detta är att LNG innehåller inget svavel samt släpper ut mindre NOX jämfört med traditionella bränslen. I denna uppsats så kommer LNG att jämföras mot diesel ur ett klimatperspektiv med fokus på koldioxidutsläpp och dess ekvivalenter. International Maritime Organisation (IMO) har infört Energy Efficiency Design Index (EEDI) krav som justerar hur mycket CO2 man får släppa ut per kilowattimme (kWh), dessa krav kommer dessutom att öka i flertalet intervaller i framtiden, varav nästa intervall redan sker i 2022 för speciella fartygstyper. Metoden som användes för att jämföra bränslena var att beräkna mol-innehållet för både LNG samt diesel, sen från den beräknade data se hur mycket koldioxid (CO2) inklusive ekvivalenter de släppte ut. Resultatet visade att under optimala förutsättningar så var LNG ett klart bättre alternativ än diesel. Däremot så kan sjöfarten ha ett problem inom framtiden från de krav som berör växthusgaser som kommer att ställas från och med 2050.

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Zatloukalová, Nikola. "Podnikatelský plán založení čerpací stanice." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2014. http://www.nusl.cz/ntk/nusl-224784.

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The main goal of this thesis is to create business plan for the establishment of the petrol station operating as BENZINA franchise. Entrepreneurship, requirements of the business plan, franchising and definition of used analysis are described in the theoretical part. Necessary analyses are performed in the analytical part. Suggested business plan and schedule of its implementation are described in the last part of this thesis.

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Moreira, Paulo Jorge Pires. "Shipping and sustainability liquefied natural gas as an alternative fuel : evidence from Portugal." Doctoral thesis, 2019. http://hdl.handle.net/10400.2/8096.

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O transporte marítimo é um elo vital do comércio mundial graças à sua capacidade, confiabilidade e relação custo-eficácia no transporte de grande quantidade de bens; nenhum outro modo de transporte consegue alcançar tais economias de escala. Mas este argumento subestima os custos reais. A frota marítima internacional, excluindo barcos de pesca e navios militares, produziu em 2012 cerca de 796 milhões de toneladas (Mt) de dióxido de carbono (CO2) e 816 Mt de dióxido de carbono equivalente (CO2e) de gases de efeito de estufa (GEE) combinando dióxido de carbono (CO2), metano (CH4) e óxido nitroso (N2O) correspondendo a cerca de 3,1% das emissões globais (IMO-International Maritime Organization, 2015; Rahman e Mashud, 2015) e é um dos setores de mais rápido crescimento em termos de emissões de GEE (Gilbert, Bows e Starkey, 2010; Bows-Larkin, 2014) previstas aumentar entre 102% a 193% em relação aos níveis de 2000 até 2050 (Bows-Larkin, 2014), crescendo a uma taxa mais elevada do que a taxa média de todos os outros sectores, com excepção da aviação. Como as emissões marítimas são produzidas, em grande parte, em mar aberto e por navios registados em países de bandeira de conveniência, foram excluídas dos compromissos nacionais no âmbito do Protocolo de Quioto de 1997, que cedeu o controlo à IMO o organismo da ONU responsável pelo sector1. De acordo com o Maritime Knowledge Centre da IMO, a frota mercante mundial de navios com pelo menos 100 gross tonnage (tonelagem bruta) era composta por 93.161 navios no final do ano de 2016. Espera-se que um número crescente de navios mercantes entre em operação nas próximas décadas, nomeadamente navios porta-contentores de grande capacidade, navios metaneiros e outros adstritos a actividades diversificadas como produção, armazenamento e descarga de gás natural e de petróleo (em inglês Floating Production Storage and Offloading - FPSOs). Os combustíveis marítimos tradicionais também produzem emissões de óxido de enxofre (SOx), óxidos de azoto (NOx) e micropartículas e o impacto sobre o ambiente dos poluentes primários e secundários resultantes da combustão do fuelóleo pesado (HFO) tem contribui para a acidificação, eutrofização e formação de ozono (O3) fotoquímico (Bengtsson, 2011). Um efeito particularmente pernicioso na saúde das populações expostas é a mortalidade prematura relacionada com micropartículas inaláveis associadas com o aumento do cancro de pulmão e problemas cardiorrespiratórios (Corbett et al., 2007) e, embora os efeitos nocivos mais graves sejam particularmente sentidos nas zonas costeiras e em áreas próximas das atividades portuárias, estes efeitos também ocorrem no interior dos países devido às condições predominantes dos ventos (Corbett, Fischbeck and Pandis, 1999) incluindo efeitos transfronteiriços (Nore, 2011). Em Portugal e de acordo com o World Resources Institute, as emissões de CO2 com origem nos combustíveis marítimos cresceram 24,5%, entre 2003 e 2012, em linha com o crescimento mundial (de 26,8%) no mesmo período de dez anos (World Resources Institute, 2015). Nesta tese, para efeitos de monetarização das emissões produzidas pela frota mercante nacional serão utilizados os dados do Inventário Nacional de Emissões, dados de 2014, os quais revelam que, embora o contributo do sector para o registo nacional seja mínimo – devido nomeadamente à exiguidade da frota – o potencial de danos causados não é de todo despiciente. Técnicas para aumentar a eficiência energética e tecnologias de mitigação dos efeitos nocivos - scrubbers, (depuradores) e dispositivos catalíticos - têm sido desenvolvidas e implementadas -, no entanto, embora o seu contributo para a descarbonização do sector deva ser levado em conta, estas tecnologias não correspondem à alteração pretendida do paradigma energético e podem constituir um incentivo ao business-as-usual. Por outro lado, o recurso a combustíveis com menor conteúdo de enxofre como o diesel marítimo é contraproducente uma vez que as emissões dos motores a diesel foram recentemente classificadas como cancerígenas pelo Centro Internacional de Investigação do Cancro (Oeder et al, 2015). O que isto significa é que embora o diesel corresponda ao exigido futuramente pelo Regulamento Tier III emitido pela IMO, na realidade não respeita suficientemente as preocupações com a saúde humana. De qualquer modo as refinarias não teriam provavelmente capacidade suficiente de fornecer todo o diesel necessário para abastecer a frota mundial. Por outro lado, as medidas de redução de poluentes emitidas pela IMO poderão ver seus efeitos reduzidos pelo crescimento esperado da atividade marítima nas próximas décadas e são destinadas a ser adoptadas lentamente ao longo de um largo período de tempo e mostram um progresso muito lento no contexto de evitar um aumento de temperatura superior a 2ºC acima dos níveis pré-industriais (Gilbert, 2013; Bows-Larkin, 2014), daí a necessidade urgente de investir em novas tecnologias e em novos tipos de combustíveis.
The objective of this Ph.D. thesis is to provide important inputs for the decarbonisation of marine transport and climate change mitigation policies concerning liquefied natural gas (LNG) as a substitute fuel. Real-world results show efficiency gains from LNG compared with traditional fossil fuels burned on-board vessel’s engines even when equipped with mitigation technologies. Yet, this is a necessary but not a sufficient condition to LNG be elected as a substitute fuel. For a fuel switch of such order of magnitude to occur within a major end-use sector, other requirements are to be fulfilled: the government intervention in the public interest, and, to justify such policy intervention, the degree of social acceptability. This is accomplished by developing a social cost-benefit analysis (SCBA) performed at a regional basis after the assessment of the trade-off between the provision level of the good and Portuguese nationals’ disposable income had been examined. SCBA attaches money prices - a metric of everything that everyone can recognise - to as many costs and benefits as possible in order to uniformly weigh the policy objectives. As a result, these prices reflect the value a society ascribe to the paradigm change enabling the decision maker to form an opinion about the net social welfare effects. Empirically, emissions from the Portuguese merchant fleet weighted by their contribution for the National Inventory were used to quantify and monetise externalities compared with benefits from LNG as a substitute marine fuel. Benefits from the policy implementation are those related with the reduction of negative externalities. Costs are those determined from the price nationals are hypothetically willing-to-pay for. Conclusions show that benefits are largely superior to the costs, so action must be taken instead of a doing nothing scenario. Apart from the social ex-ante evaluation, this thesis also imprints the first step for developing furthermore complete studies in this aspect and it can help fill policy makers’ knowledge gap to what concerns to strategic energy options vis-à-vis sustainability stakeholders engagement. Although it addresses Portuguese particularities, this methodology should be applied elsewhere.

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47

Kurasaki, Ryan. "Investigation Of A Biological Fuel Cell In Methane Hydrate Marine Sediment." Thesis, 2004. http://hdl.handle.net/10125/10402.

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48

Jahn-Hwa, Yang, and 楊建華. "A study on the effects of using low sulphur marine gas oil to the fuel injection pump of marine diesel engine." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/05636224174992080444.

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碩士
國立臺灣海洋大學
商船學系所
100
This research report is made for a brief introduction in the updated MARPOL Regulations and Port Regulations of the Emission Control Areas (ECA) and focusing on the plunger and barrel’s failure of fuel injection pumps of diesel engine after short operation by using low sulphur marine gas oil when ship berthed in the restricted ports of ECA, which also increasing hard operation for the shipping company. Based on technical issues from different diesel engine manufacturers and the U.S. Power Research Inc. and concerned technical papers from other countries with their conclusions and suggestions regarding the low lubricity character of low sulphur marine gas oil. The main purpose of this research report is to investigate the auxiliary engine power failure due to wear to the plungers of fuel injection pumps, thus jeopardizing the safety of the vessels' operations. The core of this research is focusing to the action of the fuel injection pump, fuel injection and fuel quality, especially contents of the FCC particles of blending heavy fuel and the character of low lubricity of low sulphur marine gas oil, the result of this research report is a compilation of studies utilizing individual cases through investigation, trial and interview, as well as comparison and analysis of information gleaned through the fleet of the shipping company involved in the study. This research concluded that low lubricity of low sulphur MGO which will be caused the failure or premature of plunger & barrel of fuel injection pump, and the countermeasures against the trouble of fuel injection pump so as to minimize the risk during ship’s operation in future.

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PAN, HSIEN TE, and 潘顯德. "Study of Common Rail High Pressure Fuel Injection System for Large Marine Diesel Engine." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/00825578235732651523.

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碩士
國立高雄海洋科技大學
輪機工程研究所
104
In response to increasingly tough international environmental regulations and rising oil prices, the development of marine diesel engines, worth exploring in depth for. At present the mainframe manufacturers are mustering their efforts to develop high-performance fuel-efficient, saving energy and environmentally friendly hosts. The heart is the host of the high-pressure fuel injection system, fuel injection performance upgrade if the better to promote as much as possible to achieve complete combustion of fuel, so that more output horsepower can save fuel and reduce pollution of its ultimate goal. The diesel engine fuel injection after the high-pressure pump to generate sufficient pressure fuel injection pressure to the cylinder, either double or oil-type injection pump injection pressure, injection amount and injection timing by the fuel injection pump are the control, fuel pressurized by each line to the injection nozzle, and the high-pressure injection pump is a mechanical action, so that is a period of time after the parts wear out, thereby affecting the injection timing, injection pressure and injection quantity, to solve this problem, and ultimately the formation to produce high-pressure common-rail fuel injection system, the type of engine operating mode to a computer to be monitored, so the timing, injection quantity and the injection pressure can be controlled in a jet full domain of the most appropriate, complete combustion and reduce emissions, the province in order to achieve the advantages of oil and improve the performance of the engine. Marine diesel power after years of fierce competition in the shipping market, and gradually form a MAN B & W (the electronic control type of high-pressure fuel injection system) and Wärtsilä-Sulzer (RT-flex), led by two world-renowned brands. This paper will examine the highest market share of these two marine main factory, how to improve the combustion efficiency of energy-saving win performance through high-pressure common rail fuel injection system.

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Valbom, Diogo Valério Martins. "Fuel analysis." Master's thesis, 2020. http://hdl.handle.net/10362/105578.

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This individual analysis consists ofa fuel analysis, regarding both the U.S. airline industry and Southwest Airlines. Co. demonstrating how airlines and institutions try to mitigate the impact that fuel has. In the case of Southwest Airlines Co.,this analysis will quantify the impact ofbothoil prices and fuel efficiency on the share price using a sensitivity analysis. Thissensitivity analysis is based on various growth rates from multiple sources,such has, FAA (both refinery and jet fuel cost) and NYMEX crude oil futures. The value per share computed varies between $38.71and $91.24.

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Dissertations / Theses on the topic 'Marine fuels'

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