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11	A functional group approach for predicting fuel properties Abdul Jameel, Abdul Gani 03 1900 (has links) Experimental measurement of fuel properties are expensive, require sophisticated instrumentation and are time consuming. Mathematical models and approaches for predicting fuel properties can help reduce time and costs. A new approach for characterizing petroleum fuels called the functional group approach was developed by disassembling the innumerable fuel molecules into a finite number of molecular fragments or ‘functional groups’. This thesis proposes and tests the following hypothesis, Can a fuels functional groups be used to predict its combustion properties? Analytical techniques like NMR spectroscopy that are ideally suited to identify and quantify the various functional groups present in the fuels was used. Branching index (BI), a new parameter that quantifies the degree and quality of branching in a molecule was defined. The proposed hypothesis was tested on three classes of fuels namely gasolines, diesel and heavy fuel oil. Five key functional groups namely paraffinic CH3, paraffinic CH2, paraffinic CH, naphthenic CH-CH2 and aromatic C-CH groups along with BI were used as matching targets to formulate simple surrogates of one or two molecules that reproduce the combustion characteristics. Using this approach, termed as the minimalist functional group (MFG) approach surrogates were formulated for a number of standard gasoline, diesel and jet fuels. The surrogates were experimentally validated using measurements from Ignition quality tester (IQT), Rapid compression machine (RCM) and smoke point (SP) apparatus. The functional group approach was also employed to predict research octane number (RON) and motor octane number (MON) of fuels blended with ethanol using artificial neural networks (ANN). A multiple linear regression (MLR) based model for predicting derived cetane number (DCN) of hydrocarbon fuels was also developed. The functional group approach was also extended to study heavy fuel oil (HFO), a viscous residual fuel that contains heteroatoms like S, N and O. It is used in ships as marine fuel and also in boilers for electricity generation. 1H NMR and 13C NMR measurements were made to analyze the average molecular parameters (AMP) of HFO molecules. The fuel was divided into 19 different functional groups and their concentrations were calculated from the AMP values. A surrogate molecule that represents the average structure of HFO was then formulated and its properties were predicted using QSPR approaches. Functional Group NMR Surrogate Cetane Number Octane Number Heavy fuel oil
12	Particle Morphology and Elemental Composition of Heavy Fuel Oil Ash at Varying Atomization Pressures Tovar, Daniel Abraham 19 August 2013 (has links) (PDF) Land-based turbine engines are currently used to burn heavy fuel oil (HFO), which is a lower cost fuel. HFO contains inorganic material that forms deposits on turbine blades reducing output and efficiency. Magnesium based additives are used to inhibit vanadium pentoxide deposition and reduce the corrosive nature of the gas and deposits in the hot gas path of the gas turbine. The focus of this study was to determine particle morphology and elemental composition of ash when firing HFO in an atmospheric combustor at various fuel injector atomization pressures. Prior to firing, the HFO was washed with water to remove sodium and potassium. A commercially available magnesium based additive was used to inhibit the vanadium in the HFO. Fuel was injected using an air-blast atomizer at air blast atomization gage pressures of 117, 186, and 255 kPa. Ash was collected from three locations downstream of combustion: immediately following combustion (pre-cyclone), from a cyclone separator (cyclone), and finally from a position located after the cyclone separator (post-cyclone). A Philips XL30 Scanning Electron Microscope (SEM) provided images, weight percent of elements of the ash, and element maps. Images taken from the SEM clearly show two particle types: 1) hollow spherical particles, or cenospheres, and 2) submicron agglomerated spherical particles. The cenospheres contained high carbon concentrations and were found primarily in the cyclone and probe bag filter. Element maps show that cenospheres, regardless of size, predominately contain carbon, oxygen, and sulfur with lesser amounts of sodium, magnesium, aluminum, and silicon. Particles collected downstream of the cyclone were primarily sub-micron in size and inorganic in composition. It is postulated that the cenospheres are the result of incomplete combustion of fuel oil droplets while the submicron spheres are nucleated inorganic material that initially evaporated from the liquid droplets. Particle size analysis was performed for each sample location. As the injection pressure was increased; the pre-cyclone and cyclone locations had similar number mean diameters that would decrease with increasing pressure. The diameter of the post-cyclone location did not change significantly with increasing air atomization. While increasing atomization pressure decreased the carbon content of the ash at all measurement locations, the atomization had little influence on the inorganic composition of the particles. The fine condensed phase particles and the larger cenosphere particles both produced similar compositions of inorganic material. heavy fuel oil SEM atomization pressure cenospheres sub-micron particles Mechanical Engineering
13	Optimization of solid-phase extraction (SPE) as sample preparation for oil samples in forensic investigations. Chang, Aamanda January 2021 (has links) Oil spills, especially in water have happened throughout the years. The consequences from this kind of incident have always been a threat to marine life and take a lot of money and time to clean up. The forensic investigations of oil usually focus on oil spill in water, however, this kind of investigation can be applied on more areas, such as in sexual offense cases and arson. The oil from the crime scene and the oil from the suspected source are analyzed and compared to each other to see if the compositions match. The aim of this thesis was to optimize the clean-up process of heavy fuel oil (HFO) using solid-phase extraction (SPE) according to the European Committee for standardization (CEN) 15522-2 method. HFOs are black oils, containing particles and soot which will decrease injector performance. Thus, a cleanup procedure is attractive when analyzing such samples. The three factors of optimization in this study were elution volumes, solvents, and SPE sorbents.The SPE method used in this study was to use the cartridges as a filter; therefore, the samples were both loaded and eluted with an organic solvent, in this case dichloromethane (DCM) or dichloromethane/heptane (DCM/Hp). The gas chromatography mass spectrometry (GC-MS) analysis method used is described in Annex B in the CEN 15522-2 method.Concluding, increasing the eluent volume did not indicate improvement on the extraction method. In terms of the solvents, both dichloromethane and dichloromethane/heptane showed similar results. The percentage weathering plots (PW-plots) showed that the SPE sorbents (dual layer florisil/Na2SO4, florisil and silica gel sorbents) worked similar. The overall conclusion from this thesis work was that further optimization must be made before implementing the method. Solid-phase extraction (SPE) heavy fuel oil (HFO) fingerprint polycyclic aromatic hydrocarbons (PAHs) biomarkers. Chemical Sciences Kemi
14	Caractérisation et vieillissement des produits pétroliers par méthodes chimiométriques et développement spectral / Characterization and aging of petroleum products by chemometric methods and spectral development Braham Ben Said, Zeineb 13 March 2014 (has links) L'objectif de cette thèse est de caractériser les phénomènes d'oxydation de lubrifiants pétroliers et les produits lourds du pétrole. Dans les deux thématiques « lubrifiants » et «lourds pétroliers », une étude de veille stratégique a été effectuée en préalable des études analytiques et chimométriques dans ce cadre le paramètre temps est important. Il nous permet de comprendre les évolutions des domaines, leurs actualités et leur(s) pertinence(s) en précisant si ces domaines sont déjà en phase technologique et utilisation industrielle ou encore en phase de développement. Les huiles lubrifiantes doivent répondre à certaines exigences afin d'optimiser leur performance lors de l'utilisation dans le moteur. Dans ce travail, divers composés soufrés sont testés afin de déterminer le potentiel antioxydant. Deux huiles de base et sept additifs sont testés. Il apparaît que les composés soufrés avec des longues chaînes aliphatiques augmentent la résistance de l'huile, quelle que soit sa nature. Les fiouls lourds utilisés pour les moteurs de bateau peuvent être considérés comme un déchet de raffinage. Néanmoins, la spécification de ces produits est très stricte notamment pour la combustion, la stabilité et la teneur en soufre. Leurs caractérisations nécessitent l'analyse de diverses propriétés, qui sont essentielles pour le contrôle et le développement de technologies de moteurs d'entraînement. L'utilisation d'un support de diffusion permet de s'affranchir des problèmes de nettoyage de cuve couramment rencontrées. / The objective of this thesis is to characterize the phenomena of oxidation of oil lubricants and the heavy products of petroleum. In both themes « lubricating » and « Heavy Fuel Oil », a study of strategic monitoring was performed before analytical and chemometrics studies in this frame the parameter time is important. It helps us to understand changes domains, their news and their relevance and whether these domains are already in industrial use and technological phase or development stage scientific research. Lubricating oils must meet certain requirements in order to optimize their performance when operating in the engine. In this work various types of sulfur compounds are tested to identify the antioxidant potential. Two base oils and seven additives are tested. It appears that sulfur compounds with long aliphatic chains increases resistance of oil, whatever its nature. Heavy fuel oil used for boat motors can be considered as refining waste. Nevertheless the most stringent specification as burning, stability and sulfur content. Their characterizations require the analysis of various properties, which are essential for driving control and the development of engine technologies. The use of a diffusing support allows to free itself from problems of tank cleaning usually met. The aim of this work is to analyze fuel on the boat at the entrance of the engine in order to increase the motor performances and decrease the pollutants by a near infrared miniaturized sensor. Chimiométrie Pls Simplisma Proche infrarouge Moyen infrarouge Lubrifiant Fioul lourd Hfo Oxydation Chemometry Pls Simplisma Near infrared Medium infrared Lubricant Heavy fuel Hfo Oxidation
15	Investigation of rape seed oil methyl ester production and by-product utilization / Rapso aliejaus metilo esterio gamybos proceso šalutinio produkto utilizacijos tyrimas Stepanonytė, Dovilė 29 June 2007 (has links) The problems of rape seed methyl ester (RME) production process by-products utilization were analyzed, statistical data for the capacities of biodiesel production and by-products generation were presented, the prospects of biodiesel production expansion, properties and environmental impact, main production technologies, Lithuanian and foreign countries experience were described, the main aims and tasks of work were defined. The investigation of glycerol – major by-product of RME production process – utilization was accomplished. One of the new possible utilization methods was researched, when combusting glycerol with highly sulphurous (~ 2.0 %) heavy fuel oil to reduce SO2 emissions, which limit value in the flue gas can not exceed 1700 mg/Nm3 (according to EU Directive 1999/32EC and LAND 43-2001 „Norms for the exhaust of pollutants from large fuel burning equipment“). The heavy fuel oil – glycerol emulsion was prepared in the pilot plant operating in the laboratory conditions, the most optimal ratio (1:1) for heavy fuel oil emulsification was estimated, the dispersivity investigation of heavy fuel oil - glycerol emulsion samples was performed. The experimental heavy fuel oil and obtained emulsion combustion investigations were carried out in VGTU Institute of Thermal Insulation pilot plant and in the thermal oxidation boiler „UMISA-CR/11,9 (13)“ at JCS „Rietavo veterinarinė sanitarija“. The CO, NOx, SO2 and particulate matter concentration values for heavy fuel oil and... [to full text] / Baigiamajame darbe išnagrinėtos rapso aliejaus metilo esterio (RME) gamybos proceso šalutinių produktų utilizacijos problemos, pateikti statistiniai duomenys apie biodyzelino gamybos bei susidarančių šalutinių produktų apimtis, aprašytos biodyzelino gamybos plėtros perspektyvos, savybės bei poveikis aplinkai, pagrindinės gamybos technologijos, Lietuvos bei užsienio šalių patirtis šioje srityje, apibrėžti pagrindiniai darbo tikslai ir uždaviniai. Atliktas RME gamybos proceso pagrindinio šalutinio produkto – glicerolio – utilizacijos tyrimas. Išanalizuotas vienas iš naujų galimų utilizavimo būdų - deginti glicerolį kartu su sieringu (~ 2,0 %) mazutu, siekiant sumažinti SO2 emisijas, kurių nustatyta ribinė vertė dūmuose negali būti didesnė kaip 1700 mg/Nm3 (pagal ES Direktyvą 1999/32EC ir LAND 43-2001 „Išmetamų teršalų ir didelių kurą deginančių įrenginių normos“). Laboratorinėmis sąlygomis stendiniame įrenginyje paruošta mazuto-glicerolio emulsija, nustatytas optimaliausias mazuto emulgavimo gliceroliu santykis (1:1), atlikti mazuto emulsijos bandinių homogeniškumo tyrimai. Eksperimentiniai mazuto bei gautų emulsijų deginimo bandymai buvo atlikti VGTU Termoizoliacijos instituto eksperimentiniame stende bei UAB „Rietavo veterinarinė sanitarija“ termooksidaciniame katile „UMISA-CR/11,9 (13)“. Išmatuotos mazuto ir mazuto-glicerolio emulsijos CO, NOx, SO2 ir kietųjų dalelių emisijos bei palygintos su jų didžiausiomis leistinoms vertėmis. Remiantis gautais rezultatais pateiktos... [toliau žr. visą tekstą] RME Transesterification Heavy fuel oil - glycerol emulsion Homogeneity SO2 concentrations RME Transesterifikacija Mazuto-glicerolio emulsija Homogeniškumas SO2 koncentracijos
16	Paroplynová elektrárna s spalovacími motory / Combi-Cycle with piston engine Kubik, Martin January 2012 (has links) The scope of this diploma thesis of focused on processing and calculation of the technological scheme for combi-cycle power plant with piston engine using heavy fuel oil. There are analyzed demands of piston engine for HFO and design of technological process preparation. This thesis analyzes the suitable locations, service options and alternative solution - heating plant with piston engines. Benefits of each option are assessed in the economic model, assuming power as a source of base load and providing support services. The results are intended to assess feasibility of the investment project.
17	Simulátor GateCycle a jeho aplikace / GateCycle simulator and its applications Svoboda, Adam January 2018 (has links) Hlavná náplň tejto práce je oboznámenie so softvérom GateCycle od spoločnosti General Electric a jeho následná aplikácia na simulovanie industriálneho parného kotla produkujúceho 120 t pary za hodinu. Dizajn práce je vo forme výučbového materiálu, ktorý môže byť použitý vo výuke predmetu procesného inžinierstva zameraného na simulačné softvéry. Prvá časť práce je venovaná krátkej teórii o simulačných softvéroch a uvádza niekoľko najznámejších procesných inžinierskych simulačných programov. Druhá časť je napísaná formou GateCycle manuálu. V krátkosti predstavuje pracovné prostredie a rozhranie softvéru, demonštruje ako vytvoriť a spustiť simulačný model, zadať vstupné dáta a vytvoriť reporty. Tretia časť práce je praktická, vybraný industriálny parný kotol je prezentovaný a následne je vybudovaný jeho simulačný model. Táto časť je vytvorená vo forme príručky „krok za krokom“ vysvetľujúcej ako vytvoriť model kotla a aké dáta boli zadané do jednotlivých procesných aparátov. Kotol je simulovaný v 3 režimoch, využívajúc zemný plyn, ťažký vykurovací olej, či dechtovú vykurovaciu zmes ako palivo a je prevádzkovaný za mierne rozličných procesných podmienok. V závere sú vypočítané spotreby paliva porovnané s reálnymi prevádzkovými dátami a je vyhodnotená presnosť výpočtov softvéru GateCycle v týchto konkrétnych prípadoch.
18	Liquid Natural Gas : A study of the environmental impact of LNG in comparison to diesel / Flytande Naturgas : En studie om LNG:s klimatpåverkan i jämförelse med diesel Edfors, Jonas, Bremberg, Robin January 2021 (has links) 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. Methane LNG Engine Marine Mole Methane Slip Ship CO2 CH4 Emission IMO Exhaust gas Environment Propulsion Heavy Fuel Oil Ultra Low Fuel Oil Diesel Marine Diesel Oil ECA SECA NECA IMO g/kWh EEDI LSFO Metan LNG Motor Mol Skepp Miljö Miljövänligt Tjockolja Diesel Marine Diesel Avgas CO2 CH4 ECA SECA NECA IMO g/kWh EEDI LSFO Energy Engineering Energiteknik
19	Distribuční soustava Kypru - realizovatelnost obnovitelných zdrojů a přenos energie / Distribution system of Cyprus - feasibility of renewable energy sources and transfer of energy Šimonová, Lucie January 2011 (has links) Until a few decades ago few people could imagine that the photovoltaic, solar thermal and other power based on renewable resources, will become a reality. Today people from all over the world on the contrary try at full blast derive benefit from of all possible available source. Using sunlight as a source of energy is first enforced only for small devices such as calculators for charging the battery, but now we are able to produced energy from the sun to supply people around the world. Of course it is not possible supply consumer sector plus firm only from performances renewable power supply. Therefore endeavour is derive benefit from classical energy production at the same time with others power supply. The basic components of photovoltaic and solar thermal power are panels. The panels are made of different materials in different shapes and sizes. During production, the resulting effect looks in addition to costs associated with production. For photovoltaic and solar thermal power plant requires sufficient sunlight. The sunshine has biggest intensity on south of ours planets. Therefore endeavour is build lump these power station just in stand with bigger intensity sunshine. One of them is just Cyprus, too.

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