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

Molecular studies of asphalt, mummy and Kassel earth pigments their characterisation, identification and effect on the drying of traditional oil paint /

Languri, Georgiana Maria, January 1900 (has links)
Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met samenvatting in het Roemeens en Nederlands.
72

Effect of energy dissipation rate on bitumen droplet size

Mussbacher, Scott L. January 2009 (has links)
Thesis (M. Sc.)--University of Alberta, 2009. / Title from pdf file main screen (viewed on Sept. 1, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Chemical Engineering, Department of Chemical and Materials Engineering, University of Alberta." Includes bibliographical references.
73

High Pressure Oxy-fired (HiPrOx) Direct Contact Steam Generation (DCSG) for Steam Assisted Gravity Drainage (SAGD) Application

Cairns, Paul-Emanuel January 2013 (has links)
Production in Canada’s oil sands has been increasing, with a projected rate of 4.5 million barrels per day by 2025. Two production techniques are currently used, mining and in-situ, with the latter projected to constitute ~57% of all production by that time. Although in-situ extraction methods such as Steam Assisted Gravity Drainage (SAGD) are less invasive than mining, they result in more greenhouse gas (GHG) emissions per barrel and require large amounts of water that must be treated and recycled with a make-up water requirement of about 10%. CanmetENERGY is developing a steam generation technology called the High Pressure Oxy-fired Direct Contact Steam Generator (HiPrOx/DCSG, or DCSG for short) that will reduce these water requirements and sequester GHGs. This study evaluates the technical feasibility of this technology using process simulations, bench-scale testing, and pilot-scale testing. At first, a method in which to integrate the DCSG into the SAGD process was presented and process modeling of expected system performance was undertaken. The process simulations indicated that DCSG decreased the energy intensity of SAGD by up to 7.6% compared to the base SAGD case without carbon capture and storage (CCS), and up to 12.0% compared to the base SAGD case with CCS. Bench-scale testing was then performed using a pressurized thermogravimetric analyzer (PTGA) in order to investigate the effects of increased pressure and high moisture environments on a Canadian lignite coal char’s reactivity. It was found that under reaction kinetic-controlled conditions at atmospheric pressure, the increased addition of steam led to a reduction in burning time. The findings may have resulted from the lower heat capacity and higher thermal conductivity of steam compared to CO2. At increased pressures, CO2 inhibited burnout due to its higher heat capacity, lower thermal conductivity, and its effect on C(O) concentrations on the particle surface. When steam was added, the inhibiting effects of CO2 were counteracted, resulting in burnout rates similar to pressurized O2/N2 environments. These preliminary results suggested that the technology was feasible at a bench-scale level. Conflicting literature between bench-scale and pilot-scale studies indicated that pilot-scale testing would be advantageous as a next step. At the pilot-scale, testing was performed using n-butanol, graphite slurry, and n-butanol/graphite slurry mixtures covering lower and upper ends in fuel reactivity. It was found that stable combustion was attainable, with high conversion efficiencies in all cases. With the n-butanol, it was possible to achieve low excess oxygen requirements, which minimizes corrosion issues and reduce energy requirements associated with oxygen generation. With graphite slurry, it was found that it was possible to sustain combustion in these high moisture environments and that high conversion was achieved as indicated by the undetectable levels of carbonaceous materials observed in downstream equipment. Overall, these studies indicate that DCSG is technically feasible from the perspectives of energy and combustion efficiencies as well as from a steam generation point of view. Future work includes the investigation of possible corrosion associated with the product gas, the effect of CO2 on bitumen production, the nature of the mineral melt formed by the deposition of the dissolved and suspended solids from the water in the combustor, and possible scaling issues in the steam generator and piping associated with mineral deposits from the dissolved and suspended solids in the produced water is recommended.
74

Analyse thermique avancée pour l’étude et la caractérisation de produits pétroliers complexes tels que les bitumes / Advanced thermal analysis for the sudy and characterization of complex petroleum products

Moncel, Matthieu 19 December 2014 (has links)
Au cours de cette thèse, de nouvelles méthodes d’analyse thermique et de traitement des données applicables à l’étude et la caractérisation de produits pétroliers complexes, ont été proposées, afin de mieux caractériser les bitumes. Le bitume, sous-produit de l’industrie pétrolière, est un matériau complexe dont les propriétés et la composition changent au gré des cocktails de pétroles bruts ou des procédés de raffinage. Une connaissance approfondie des propriétés de chaque bitume est donc nécessaire. Les tests mécaniques normés utilisés aujourd’hui pour caractériser le bitume sont insuffisants. Afin de pallier ce problème les techniques de DSC avancées ont été exploitées. Ce travail a porté principalement sur l’étude des trois phénomènes pouvant être observés au cours du chauffage des bitumes: la transition vitreuse, la cristallisation et la fusion. La première partie de ce travail a été consacrée à l’étude de ces trois phénomènes sur des molécules modèles, la diéthanolamine et la triéthanolamine. L’intérêt de la perturbation stochastique de température (TOPEM®) réside notamment dans la possibilité de séparer certains phénomènes se produisant sur un même domaine de températures. La méthodologie développée a ensuite été appliquée aux bitumes afin de mettre en évidence des corrélations entre données DSC (fraction cristallisable, température de transition vitreuse, température et enthalpie de fusion) et données mécaniques. Il a été montré également que la calorimétrie ultra-rapide permet de séparer certains phénomènes grâce à une approche différente mais complémentaire à la perturbation stochastique de température TOPEM®. / This thesis tackled new methods of thermal analysis and data treatment applicable to the study and characterization of complex petroleum products. The objective was to better characterize bitumen, which, as a by-product of petroleum industry, is a complex material. Its properties and composition are not set and change according to the cocktails of crude oils or to the refining processes. Thorough knowledge of the properties of asphalt is thus necessary to be able to use them in the best conditions. The standardized mechanical tests used today to characterize the asphalt are insufficient. To compensate for this problem, the techniques of advanced DSC were exploited. This work concerned mainly the study of three phenomena which can be observed during the heating of asphalts: glass transition, crystallization, and melting. The first part of this work was dedicated to the study of these three phenomena on model molecules _ the diethanolamine and the triethanolamine _ as they were presenting thermal events in a range of temperatures similar to the one of bitumen. The interest of the stochastic temperature perturbation (TOPEM®) lies in particular in the possibility of separating some phenomena occurring on the same range of temperatures. Thus, thanks to this method, glass transition can be analyzed independently of the enthalpic relaxation or of the crystallization. The developed methodology was then applied to bitumen so as to highlight correlations between DSC data and mechanical data . It was also shown that the ultra-fast calorimetry enables to separate some phenomena thanks to a different but complementary approach of stochastic temperature perturbation TOPEM®.
75

Multi-Scale Characterization of Bitumen Doped with Sustainable Modifiers

January 2020 (has links)
abstract: This research is a comprehensive study of the sustainable modifiers for asphalt binder. It is a common practice to use modifiers to impart certain properties to asphalt binder; however, in order to facilitate the synthesis and design of highly effective sustainable modifiers, it is critical to thoroughly understand their underlying molecular level mechanisms in combination with micro and macro-level behavior. Therefore, this study incorporates a multi-scale approach using computational modeling and laboratory experiments to provide an in-depth understanding of the mechanisms of interaction between selected modifiers and the constituents of asphalt binder, at aged and unaged conditions. This study investigated the effect of paraffinic wax as a modifier for virgin binder in warm-mix asphalt that can reduce the environmental burden of asphalt pavements. The addition of wax was shown to reduce the viscosity of bitumen by reducing the self-interaction of asphaltene molecules and penetrating the existing nano agglomerates of asphaltenes. This study further examined how the interplay of various modifiers affects the modified binder’s thermomechanical properties. It was found that the presence of wax-based modifiers has a disrupting effect on the role of polyphosphoric acid that is another modifier of bitumen and its interactions with resin-type molecules. This study was further extended to using nanozeolite as a mineral carrier for wax to better disperse wax in bitumen and reduce the wax's adverse effects such as physical hardening at low service temperatures and rutting at high service temperatures. This novel technique showed that using a different method of adding a modifier can help reduce the modifier's unwanted effects. It further showed that nanozeolite could carry wax-based modifiers and release them in bitumen, then acting as a scavenger for acidic compounds in the binder. This, in turn, could promote the resistance of asphalt binder to moisture damage by reducing the quantity of acidic compounds at the interface between the binder and the stone aggregates. Furthermore, this study shows that iso-paraffin wax can reduce oxidized asphaltene molecules self-interaction and therefore, reduce the viscosity of aged bitumen while cause brittleness at low temperatures. Additionally, a cradle to gate life-cycle assessment was performed for a new bio-modifier obtained from swine manure. This study showed that by partially replacing the bitumen with bio-binder from swine manure, the carbon footprint of the binder can be reduced by 10% in conjunction with reducing the cost and environmental impact of storing the manure in lagoons. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2020
76

Investigating the Mutagenicity of Polycyclic Aromatic Compounds from the Athabasca Oil Sands Region in River Otters and a Mammalian Cell Line

Gyasi, Helina 27 May 2022 (has links)
Mining operations have led to an increase in polycyclic aromatic compound (PAC) concentrations in the Alberta oil sands area. However, the toxicity of most PACs and PAC mixtures is not well characterized. Some PACs and PAC mixtures are known to be mutagenic, though there is limited research on the genotoxicity of PACs from the Alberta oil sands to wildlife. This thesis tested the hypothesis that anthropogenic sources of PACs from the Alberta oil sands are mutagenic to wildlife. The objectives were: 1) to determine whether wildlife with increased exposure to PACs had increased mutations, and 2) to determine whether an anthropogenic source of PACs is mutagenic in a controlled lab setting. For the first objective, we used a single-molecule polymerase chain reaction (SM-PCR) assay to detect microsatellite mutations in river otters with differing liver tissue PAC concentrations in the Athabasca oil sand region (AOSR; Alberta, Canada). For objective two, an in vitro mammalian mutagenicity assay with the FE1 MutaMouse epithelial cell line (FE1) was used to determine the mutagenic potential of a bitumen extraction by-product, tailings pond bitumen. We found that PAC exposure in the AOSR was positively correlated with elevated microsatellite mutations in river otters. From the in vitro study, tailings pond bitumen extracts did not induce lacZ mutations in the FE1 cells. Differences in detection methods between the two assays and PAC profiles between the otter tissue and tailings pond bitumen are suspected reasons for contradictory results. Further investigation of the different sources and PAC profiles within the AOSR environment and wildlife food web will provide insights on what types of PACs are mutagenic. Cytotoxicity, observed following exposure to tailings pond bitumen extracts, also suggests other toxicity pathways should be considered when investigating the toxicity of bitumen from the AOSR. Overall, this thesis provided data on the potential mutagenicity of PACs in the AOSR, which can be used to elucidate potential molecular mechanisms of toxicity in wildlife exposed to oil processing contaminants.
77

Preparation of novel bitumen nanocomposites out of polymer-modified montmorillonite nanoparticles

Belke, Eduard 02 August 2017 (has links)
To extend the time of service of asphalt roads modified montmorillonite nanoparticles were incorporated into bitumen with the aim of creating a gas barrier inside the bitumen which slows down the diffusion of oxygen through the bitumen. For this purpose [montmorillonite/alkyl-quat-primer] adducts ([MMT/PEI(nkD)xQyR]) were fabricated in which single-montmorillonite platelets were coated by a ultrathin polymer film by reacting montmorillonite particles with poly(ethylenimine) based polycations. The alkyl-quat-primer polymers were synthesised by adding ammonium groups and alkyl chains to hyperbranched poly(ethylenimine)s in a solvent-free reaction. Adducts with fully intercalated polymers were obtained when the polymers were reacted with an aqueous solution of [MMT/CTAB] or by mixing the polymers with montmorillonite and CTAB in an aqueous solution. The polymers replaced the CTAB in an intermediate formed [MMT/CTAB] adduct and adhered strongly to the montmorillonite due to a cooperative electrostatic interaction between the positively charged ammonium moieties of the macromolecules and the negatively charged montmorillonite surface. [MMT/alkyl-quat-primer] and [MMT/CTAB] adducts were incorporated via a single screw extruder into polymer- and non-polymer-modified bitumina to create bitumen-nanocomposites. Composites prepared under optimised conditions exhibited an adduct network inside the bitumen at adduct concentrations larger 5 wt.% and when non-polymer modified bitumina were modified. The aspect ratio of the incorporated montmorillonite platelets depended strongly on the adduct composition and the used bitumen, and was with [MMT/PEI(10kD)10Q80R10] adducts were very high (~ 300 - 1000) but with [MMT/PEI(10kD)10Q60R14] and [MMT/CTAB] adducts considerably lower (~ 30 - 90).
78

Bitumen in Neolithic Iran: Biomolecular and isotopic evidence.

Gregg, M.W., Brettell, Rhea C., Stern, Ben January 2007 (has links)
no / This paper presents the results of the chemical analysis of materials recovered from two of the earliest agricultural villages in southwestern Iran and a late Neolithic pastoral encampment in nearby Khuzistan. Gas chromatography - mass spectrometry (GC-MS) revealed biomarker compounds characteristic of bitumen in residues from ceramic vessels supporting the excavators¿ contention that the interior surfaces of some vessels were coated with a thin layer of such material and confirmed that ¿fragments¿ collected during excavation were indeed bitumen. Biomolecular and isotopic analysis of the bitumen indicated that the sources utilized lie in the Susa and Deh Luran regions of southwestern Iran. / NERC (MSc); AHRC (PhD)
79

Relationship Between Bitumen and Copper-Lead-Zinc Mineralization in the Mid-Silurian Carbonates in the Vicinity of Hamilton, Ontario

Cheung, Sha-Pak 05 1900 (has links)
<p> Previous workers in the Hamilton area have pointed out the occurance of lead and zinc mineralization within the Mid-Silurian carbonate beds. They also mentioned the existance of bitumens in these rock units.</p> <p> Analysis of 30 dolomite samples and separated bitumens by atomic absorption for Cu, Pb, Zn showed that the localization of the metals in the carbonates was controlled by the concentration of the bitumens in the rocks.</p> <p> Analysis of 5 bitumens samples by atomic absorption for Cu, Pb, Zn suggested that the bitumens act merely as a reducing agent and are not preferred sites for base metal accumulation.</p> / Thesis / Bachelor of Science (BSc)
80

Biodegradability of Diluted Bitumen (Dilbit)

Deshpande, Ruta S. 20 October 2016 (has links)
No description available.

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