Дисертації з теми "Bitumen Analysis"

Development of new asphalt technologies to reduce both energy consumption and CO2 production has attracted great interest in recent years. The use of foam bitumen, as one of them, is attractive due to the low investment and production cost. Formation and decay of foam bitumen is a highly dynamic temperature dependent process which makes characterization difficult. In this thesis, new experimental tools were developed and applied for characterizing the foam bitumen during the hot foaming process.  One of the main goals of this study was to improve understanding and characterization of the foam bitumen formation and decay. X-ray radiography was used to study the formation and decay of foam bitumen in 2D representation. The results demonstrate that the morphology of bubble formation depends on the types of bitumen used. Moreover, theoretical investigation based on the 3D X-ray computed tomography scan dataset of bubble merging showed that the disjoining pressure increased as the gap between the bubbles in the surface layer (foam film) decreased with time and finally was ruptured.   Examining the foam bitumen stream right at the nozzle revealed that foam bitumen at a very early stage contains fragmented pieces of irregular size rather resembling a liquid than foam. The result from thermogravimetric analysis demonstrated that residual water content depends on the initial water content, and was found to be between 38 wt% and 48 wt% of the initial water content of 4 wt% to 6 wt%. Moreover the influence of viscosity and surface tension on bubble shape and rise velocity of the bubbles using level-set method was implemented in finite element method. The modeling results were compared with bubble shape correlation map from literature. The results indicated that the bubble shapes are more dependent on the surface tension parameters than to the viscosity of the bitumen, whereas the bitumen viscosity is dominant for bubble rising velocity.

QC 20160303

This doctoral thesis consists of a literature review, presented in two papers, and another six papers describing experimental studies of the influence of different kinds of wax and polyphosporic acid on bitumen and asphalt concrete mixture properties. The literature review should give an extensive description of the field of knowledge concerning wax in bitumen. Effects of wax in crude oil, bitumen and asphalt concrete as well as test methods for studying these effects are described. Theories behind possible mechanisms are also discussed, and commercial wax as additive to bitumen for different purposes included. The experimental parts comprise laboratory studies involving totally five 160/220 penetration base bitumens from different sources, two isolated bitumen waxes, five commercial waxes and one polyphosphoric acid. Asphalt concrete slabs, containing base or modified bitumen were prepared and tested. Binder properties were evaluated using different types of laboratory equipment, such as dynamic shear rheometer (DSR), bending beam rheometer (BBR), differential scanning calorimeter (DSC), force ductilometer, as well as equipment for determining conventional parameters like penetration, softening point, viscosity, and Fraass breaking point. Fourier Transform Infrared (FTIR) spectroscopy and Thin Layer Chromatography (TLC-FID) were used for chemical characterization. The binders were aged by means of the rolling thin film oven test (RTFOT) and pressure ageing vessel (PAV) in combination. Asphalt concrete properties were evaluated at low temperatures using the tensile strain restrained specimen test (TSRST) and creep test at -25°C. Dynamic creep testing was performed at 40°C, as well as complex modulus tests between 0 and 20°C. Binder test results indicated that the magnitude and type of effect on bitumen rheology depend on the bitumen itself, type of crystallizing fraction in the bitumen and/or type and amount of additive used. Bitumen composition was found to be of decisive importance. Adding polyethylene wax or polyphosphoric acid, especially to a non-waxy 160/220 penetration grade bitumen, showed no or positive effects on the rheological behaviour at low temperatures (decrease in stiffness) as well as medium and high temperatures (increase in complex modulus and decrease in phase angle). However, the corresponding positive effects could not be shown in dynamic creep testing (at 40°C) of asphalt concrete mixtures containing these modified binders. Adding FT-paraffin decreased the physical hardening index for all bitumens. Also polyethylene wax and montan wax showed this effect for some bitumens. Slack wax showed a large increasing effect on physical hardening, and polyphosphoric acid none or a minor negative effect. No correlation between physical hardening index (PHI) and wax content by DSC was found in this study, involving both natural bitumen wax and commercial wax. Addition of the commercial waxes used showed no or marginally positive influence on bitumen ageing properties for the bitumens and test conditions used. Comparing asphalt mixture test results to the corresponding binder test results, the effects on asphalt mixtures from adding commercial wax or polyphosphoric acid were less evident. Significant binder physical hardening by BBR could not be confirmed by TSRST.
QC 20101006

The road system under the care and control of the State of Queensland, Australia has an estimated replacement value of $23 Billion (US$12 billion), excluding structures. Pavement management systems for recording, rating, and predicting a pavement's condition are used to prudently manage this large asset. Tne of the fundamental components of a pavement management system is the method of determining a pavement's rate of deterioration over time. Throughout the world, "pavement roughness" is one of the most widely used methods of measuring the performance of a pavement. Queensland is a large State, having an approximate area of 1.7 million square kilometres, and incorporates many small communities separated by vast distances. The majority of bitumen sealed pavements exist in low traffic volume rural areas, and consist of either a flexible unbound granular pavement or a semi-rigid modified granular pavement. This study has focussed on the roughness progression of these pavement types. Roughness data has been collected at varying frequencies since 1987, across the State's road network. In order to understand roughness progression behaviour, this research has considered 16,000 pavement segments (each lkm) from all parts of the State. This number is significant, as many previous research efforts, which form the basis of the current roughness progression models, have been based on the study of typically between forty and several hundred pavement segments. This extensive database has been used in this study to investigate trends in roughness pogression over time (~R). Traditionally, roughness progression has been represented in many road asset management models as an exponential relationship, providing rapidly increasing roughness values as the pavement approaches the end of its theoretical life. However, this relationship has not been commonly observed in the State's pavement asset. Investigations revealed that a linear relationship, termed the Linear Roughness Progression Rate (LRPR), represented the roughness progression of the pavement segments very well, and thereby assists in the identification of poor performing pavement segments. Pavement maintenance costs can also be used to identify poor performing pavement segments, based on excessive use of pavement maintenance funds to maintain functionality. This information assists in 'unmasking' pavements that may possess an umepresentative LRPR. For this reason, the effects of pavement maintenance costs (~PMC) on roughness progression have also been examined. Independent variables which are typically considered to affect roughness progression, have been examined with LRPR in this study. These variables include traffic volume, traffic loading, pavement type, subgrade soil classification, climate (rainfall, temperature, Thomthwaite Index), pavement age, and width of bitumen surface (seal width). It has been established that the roughness progression of each individual pavement segment is unique. No particular formula or model has been identified, which can accurately predict the roughness progression of any particular pavement segment from a population, based upon known values of the independent variables. In order to develop an understanding of the effects of these variables on pavement performance, a means of rating a pavement's condition using a combination of LRPR and excessive pavement maintenance expenditure has been established. Subsequently, a discrete rating scale from "Good", "Fair" to "Poor" has been used. The effects of the independent variables on pavement rating have been examined across the population of study pavement segments, using summary charts. This has enabled the proportions of pavement rated within each category to be examined with changes in each independent variable, to establish whether that variable has a global influence on pavement rating. For instance, whether the proportion of pavements rated "Poor" varies with Annual Average Daily Traffic. These summary charts provide the basis of a Network Performance Profile, which has yielded a better understanding of the variables globally influencing pavement rating across the State's road network. Further, the Network Performance Profile provides insight into the inbuilt risk of the past and current pavement design and delivery system. The knowledge gained from a whole of network analysis of condition may form a catalyst for the assessment of material quality, design methods, construction technology, and contract delivery, to ensure that pavements have the best chance of performing well. Currently, road network performance is commonly defined only by a measure of the road network's 'Absolute Condition'. The Network Performance Profile developed in this study will add new measures of pavement performance to the current definition. By including a Current Network Profile, and a more robust method for predicting mid term (five year) roughness values, asset managers will have a suite of information on historic, current, and estimated future road network condition, to use in evaluating the impact of previous and current management decisions. Pavement roughness prediction analysis, based on site-specific extrapolation of LRPR, has shown that at least six time-series roughness data points are required if an accurate short term prediction (4 to 6 year) is to be achieved. It is believed that the research of roughness progression has highlighted the unique nature of pavement segment deterioration. It is interesting to note that all categories of pavements suffer from a range of good to poor performance, and this finding is considered to be one of the keys in understanding pavement behaviour. At a network level, the study of performance has been considered very successful and has not only provided a robust methodology for quantifying road network performance, but also provides information for input into the improvement of technical policies and funding distribution decisions.

In this thesis, the Mechanical properties of polypropylene yarn of outer protection layer on Submarine High Voltage Cable, twisted around submarine cable,is determined on various conditions at ABB Company. In the first step, tensile tests are done with polypropylene yarn specimens with and without Bitumen at Room temperature. In the second step,tensile tests are done with polypropylene yarn specimens with and without Bitumen and with knotted polypropylene yarn namely: the Fishermen’s knot, the Weaver’s knot, the Square knot and the Overhand knot at Warm Condition (60˚c) and Cold Condition(-5˚c). In the final step,it is proposed to obtain numerical solution using FEM analysis with ABAQUS Software to obtain the hoop stress , the yarn stresses from twisting cable and analyzing of the cylindrical buckling in the buckling torsion and buckling bending on the outer layer of submarine cable with polypropylene material that is mixed with Bitumen.

The Nigeria economy is wholly dependent on revenue from oil. However, bitumen has been discovered in the country since 1903 and has remained untapped over the years. The need for the country to complement oil exploration with the huge bitumen deposit cannot be overemphasized. This will help to improve the country's gross domestic product (GDP) and revenue available to government. Bitumen is classifled as heavy crude with API (American petroleum Institute) number ranging between 50 and 110 and occurs in Nigeria, Canada, Saudi Arabia, Venezuela etc from which petroleum products could be derived. This dissertation looked at the Canadian experience by comparing the oil and tar sand deposit found in Canada with particular reference to Athabasca (Grosmont, Wabiskaw McMurray and Nsiku) with that in Nigeria with a view of transferring process technology from Canada to Nigeria. The Nigeria and Athabasca tar sands occur in the same type of environment. These are the deltaic, fluvial marine deposit in an incised valley with similar reservoir, chemical and physical properties. However, the Nigeria tar sand is more asphaltenic and also contains more resin and as such will yield more product volume during hydro cracking albeit more acidic. The differences in the components (viscosity, resin and asphaltenes contents, sulphur and heavy metal contents) of the tar sands is within the limit of technology adaptation. Any of the technologies used in Athabasca, Canada is adaptable to Nigeria according to the findings of this research. The techno-economics of some of the process technologies are. x-rayed using the PTAC (petroleum technology alliance Canada) technology recovery model in order to obtain their unit cost for Nigeria bitumen. The unit cost of processed bitumen adopting steam assisted gravity drainage (SAGD), in situ combustion (ISC) and cyclic steam stimulation (CSS) process technology is 40.59, 25.00 and 44.14 Canadian dollars respectively. The unit cost in Canada using the same process technology is 57.27, 25.00 and 61.33 Canadian dollars respectively. The unit cost in Nigeria is substantively lesser than in Canada. A trade off is thereafter done using life cycle costing so as to select the best process technology for the Nigeria oil/tar sands. The net present value/internal rate of return is found to be B$3,062/36.35% for steam assisted gravity drainage, B$I,570124.51 % for cyclic steam stimulation and B$3,503/39.64% for in situ combustion. Though in situ combustion returned the highest net present value and internal rate of return, it proved not to be the best option for Nigeria due to environmental concern and response time to production. The best viable option for the Nigeria tar sand was then deemed to be steam assisted gravity drainage. An integrated oil strategy coupled with cogeneration using MSAR was also seen to considerably amplify the benefits accruable from bitumen exploration; therefore, an investment in bitumen exploration in Nigeria is a wise economic decision.
Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2010.

Etude de la relation entre la teneur en vanadium des bitumes et leur vitesse de vieillissement. Mise au point d'une méthode de dosage rapide du vanadium dans les bitumes par absorption atomique en four graphite. A la suite d'un vieillissement artificiel, il est montre par des essais physiques et par chromatographie, que la nature du chelate dans lequel est engagé le groupement Vanadyl, ainsi que celle des substrats auxquels il peut se fixer, doivent intervenir sur l'éventualité d'une réaction d'oxydation. Observation des organisations moléculaires, telles qu'elles se développent au sein du matériau, par microscopie électronique, après cryofracture

Les composés saturés des bitumes c'est-à-dire les alcanes et les cyclanes sont séparés des bitumes par précipitation sélective et chromatographie d'adsorption. Ils sont analysés par des méthodes spectrométriques et chromatographiques. L'influence des composés saturés sur les démixtions et les propriétés mécaniques dynamiques du bitume est déterminée par microscopie en contraste de phase et en lumière polarisée

There are many variables that affect the viscoelastic properties of asphalt mixtures with time, among which age hardening may be considered one of the important ones. Age hardening of asphalt mixtures is an irreversible process, which contributes to a reduction of the durability of pavements and eventually increases the maintenance cost. Beside the environmental effects, ageing in asphalt mixture depends on the physicochemical properties of bitumen and mixture morphology which is a combined effect of aggregate packing, porosity, air void distribution and their interconnectivity. Thus, a clear understanding on the physicochemical properties of bitumen and mixture morphology may help to predict the performance of asphalt mixtures, which will contribute to longer-lasting and better performing pavements. When looking at the bitumen at micro-scale, one can see microstructures appearing under certain conditions which can be partially explained by the interaction of the individual phases. Since the thermo-rheological behavior of bitumen depends largely on its chemical structure and intermolecular microstructures, studying these can lead to understanding of the mechanism, speed and conditions under which this phase behavior occurs. Linking this to the changes in properties of bitumen can thus lead to better understanding of the causes of ageing, its dominant parameters and the resulting diminished mechanical response. To investigate ageing in asphalt pavements, along with physicochemical properties of bitumen one needs to also focus on the influence of mixture morphology.  It is known that asphalt mixtures with similar percentages of air-voids can have different morphologies and thus can age differently. Prediction of ageing behavior without considering the influence of mixture morphology may thus lead to erroneous conclusions and non-optimal mix design. Hence, it is important to understand the interplay between the mixture morphology and ageing susceptibility and relate this to the long term mixture performance. The aim of this Thesis was to develop fundamental understanding on ageing in asphalt mixtures that can contribute to the asphalt community moving away from the currently used accelerated ageing laboratory tests and empirical models that can lead to erroneous conclusions. To reach this aim, experimental and numerical micro-scale analyses on bitumen and meso-scale investigations on mixture morphology have been performed which, collectively, allowed for the development of a method for the prediction of asphalt field ageing, incorporating both mixture morphology and micro-scale bitumen mechanisms. For this, first, the mechanisms of surface ageing and diffusion controlled oxidative ageing were identified. Secondly, the influence of mixture morphology on asphalt ageing susceptibility was investigated. Procedures to determine the controlling parameter were then developed and an empirical framework to quantify the long-term field ageing of asphalt mixtures was set-up. For this, a combination of experimental and numerical methods was employed. An extensive experimental study was carried out to understand the fundamental mechanisms behind the micro-structural phase appearance and the speed or mobility at which they change. Atomic Force Microscopy (AFM) was utilized at different temperatures to investigate the phase separation behavior for four different types of bitumen and co-relate it with the Differential Scanning Calorimetry (DSC) measurements. Based on the experimental findings, it was concluded that the observed phase separation is mainly due to the wax/paraffin fraction presence in bitumen (Paper I). A hypothesis was developed of the appearance of a thin film at the specimen surface due to ageing which is creating a barrier, restricting thus the microstructures to float towards the surface. Furthermore, investigation showed that depending on the bitumen and exposure types this surface thin film is water soluble and thus the moisture damage becomes more severe with the ageing of asphalt pavement (Paper II and IV). A new empirical relation to obtain the primary structure coating thickness was established utilizing mixture volumetric properties and gradation using a large set of data from different literature sources. It was found that the enhanced morphological framework can be used to optimize the long term performance of asphalt mixtures (Paper III).  Thereafter, the effect of diffusion controlled oxidative ageing on different mixture morphologies based on oxidative ageing mechanism of bitumen and diffusion-reaction process was investigated using the Finite Element Method (FEM). From the FE analyses, the effect of air-void distribution and their interconnectivity combined with the aggregate packing was shown to have a significant effect on age hardening (Paper IV). It was shown that focusing only on the percentage of air-void as the main predictive ageing parameter may lead to an erroneous conclusion and non-optimal predictions of long-term behavior.  To replace such approaches, a new way to predict the long-term ageing was proposed in this Thesis, utilizing the found influences of mixture morphology and fundamental mechanism. Though additional mechanisms and non-linear coupling between them may be still needed to reach the ‘ultimate’ ageing prediction model, the current model was found to be a significant improvement to the currently used methods and may lead the way towards further enhancing the fundamental knowledge towards asphalt mixture ageing (Paper V).

QC 20140509

Notre contribution à l'étude des bitumes routiers, peut se résumer de la façon suivante: la spectroscopie de résonance magnétique nucléaire (RMN) du carbone-13 s'est révélée être un bon outil dans l'analyse structurale des bitumes. Un nouveau jeu de paramètres moléculaires moyens simples a été proposé. L'analyse de bitumes ayant et après oxydation a conduit à proposer que l'aromatisation des structures peut se faire selon trois voies principales. L'analyse fonctionnelle des bitumes a porté sur l'étude des fonctions oxygénées et soufrées. Dans le premier cas, il a été montré que la méthode d'analyse par RMN du silicium-29 permet d'étudier de manière qualitative et quantitative les produits qui possèdent de faibles teneurs en oxygène. Le contenu acide total a été déterminé et corrélé à l'évolution des bitumes au cours de l'oxydation. Dans le second cas, les études menées par X-ray absorption near edge structure ont permis de proposer la répartition en fonction de type sulfure et de type thiophénique dans le bitume. Concernant l'oxydation du soufre, cette étude a permis de montrer que la proportion du soufre subissant l'oxydation n'est que de 1%. Les réseaux de neurones ont permis d'établir des corrélations structure-propriété dans des milieux chimiquement complexes comme les bitumes. Il ressort que les paramètres moléculaires moyens servent de base dans la prédiction des propriétés rhéologiques mesurées à froid et qu'elles sont dépendantes des chaines aliphatiques.

Pour répondre aux questions posées par EUROTUNNEL, concernant la sécurité et le confort des voyageurs, nous avons conçu un programme informatique de simulation de comportement dynamique du wagon soumis aux excitations du vent des galeries d'anti-pistonnement. Dans une première partie, nous avons parlé des formes d'excitations auxquelles sera soumis le wagon, puis nous avons décrit les étages de suspension du wagon et leurs liaisons, enfin nous avons mis en évidence les différents mouvements créés sous l'effet du vent et nous avons écrit leurs équations. Dans une deuxième partie, nous avons testé plusieurs méthodes de résolution de systèmes d'équations différentielles, après comparaison des résultats obtenus par ces méthodes nous avons pu choisir une méthode qui présente le meilleur compromis : précision et rapidité. Dans la dernière partie, grâce aux amplitudes des mouvements du wagon obtenues dans différentes configurations de trafic, nous avons répondu aux questions :-Y a t-il un risque de collision du wagon entre la voûte du tunnel ? -Quels effets les amplitudes de ces mouvements auront-elles sur le confort des voyageurs ? -Peut-il se produire pour certaines vitesses de trafic des phénomènes de résonance?

Le recyclage des enrobés bitumineux fabriqués selon un procédé tiède répond aux exigences du développement durable: il limite l'apport de matériaux neufs, permet la gestion des déchets et réduit la consommation d'énergie. Le recyclage des enrobés date des années 70 ; ce qui a changé depuis, c'est la volonté de pérenniser le recyclage à fort taux, définit ici à plus de 25% d'agrégats d'enrobés (AE). Les AE contiennent une part de bitume qui est valorisable pour ses propriétés viscoélastiques de liant hydrocarboné. Il est ainsi recherché une mobilisation de ce liant vieilli dans le processus de recyclage. L'un des problèmes suspectés lors du couplage recyclage/procédé tiède est le phénomène de double enrobage pouvant impacter la rhéologie du nouveau matériau: le liant de l'AE et le liant d'apport ne se mélangeraient pas totalement du fait de l'abaissement des températures de fabrication et formeraient des couches superposées. Ce phénomène serait la cause de dysfonctionnements mécaniques au niveau de l'enrobé. Il se pose donc la question de la qualité de l'enrobage de surfaces granulaires déjà enrobées et du manque de moyens de caractérisation pour l'observation in situ de l'interface. Dans ce travail de thèse, la qualité d'enrobage des agrégats d'enrobés par un liant d'apport a été évaluée à l'échelle microscopique et macroscopique. Au niveau microscopique, il a été proposé d'utiliser un outil de micro-spectroscopie infrarouge pour évaluer in situ la qualité d'interface entre l'AE et le liant d'apport et suivre la répartition spatiale de ces deux composants au sein d'enrobés de laboratoire. Cela a nécessité un important développement expérimental afin de pouvoir appliquer un accessoire d'imagerie infrarouge aux mélanges complexes que sont les formules d'enrobés bitumineux constitués de différentes fractions granulaires et de liant bitumineux. Il a ainsi été possible, grâce à l'identification préalable de traceurs internes, de suivre la remobilisation partielle du liant vieilli de l'AE. En parallèle, au niveau macroscopique, un protocole d'essai a été développé afin d'évaluer la durabilité des enrobés contenant des forts taux d'AE (50%), notamment des enrobés fabriqués selon un procédé tiède. L'essai actuel de fatigue est l'un des essais qui permet le mieux d'évaluer la durée de vie d'une couche de chaussée. Mais cet essai accéléré est biaisé car le bitume des échantillons testés n'a pas eu le temps de vieillir comme c'est le cas sur une vraie chaussée. Dans ce travail, il a donc été proposé d'ajouter une étape de vieillissement du matériau avant les essais de fatigue, d'orniérage, de tenue à l'eau et de module complexe. Il est supposé que le comportement réel du matériau se situerait entre celui du matériau non vieilli et celui du matériau vieilli. Les principaux résultats obtenus montrent qu'un enrobé tiède contenant un taux élevé d'AE présente de bonnes performances mécaniques excepté qu'il a tendance à être plus sensible à la fatigue qu'une même formulation de matériau fabriqué à chaud ou selon un procédé tiède mais sans ajout AE
The recycling of asphalt mixtures manufactured with a warm process meets the requirements of sustainable development: it limits the use of new materials, allows waste management and reduces energy consumption. The recycling of asphalt mixtures dates from the 70's. What has changed since that is the will to sustain high rate recycling, defined here by more than 25% of Reclaimed Asphalt Pavement (RAP). RAP contains a part of bitumen that is recoverable for its viscoelastic properties of asphalt binder. It is thus desired to mobilize this aged binder in the recycling process. One of the suspected problems when coupling recycling and warm process is the phenomenon of double coating that could affect rheological properties of the new material: the RAP binder and the new binder do not would mix completely due to the reduction of processing temperatures and would form superimposed layers. This phenomenon would cause mechanical dysfunctions in the asphalt mixture. This raises the question of the quality of the coating of granular surfaces, previously coated, and lack of characterization tools for in situ observation of the interface. In this thesis work, the quality of coating of RAP by a new binder has been evaluated at the microscopic and macroscopic scales. At the microscopic level, it has been proposed to use infrared micro-spectroscopy tool to evaluate the quality of interface between the RAP and the new binder and to follow the spatial distribution of these two components within mixtures produced in laboratory. To do that, it has been necessary to carry out an important experimental development in order to apply an infrared imaging accessory to complex mixtures that are the bituminous mixtures made of different granular fractions and bituminous binder. It was then possible, based on previous identification of internal tracers, to follow the partial remobilization of RAP aging binder. In parallel, at the macroscopic level, a testing protocol has been developed to evaluate the durability of high rate recycled asphalt mixtures (50% of RAP), including mixes produced in a warm process. The current fatigue test is one of the tests that best evaluate the lifetime of a pavement layer. But this accelerated test is biased because the bitumen of the mixtures tested did not have time to aged, as occurs in the case on a real road. In this work, it was proposed to add an aging step of the material before fatigue test, rutting test, modulus test and moisture damage test. It is assumed that the real behavior of the material would range between that of the unaged material and that of aged material. The main obtained results show that warm mixture asphalt containing high rate of RAP exhibit good mechanical performance, with a trend to be more susceptible to fatigue than a similar hot mixture or a warm mixture without added RAP

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)

When the present work begun, the Refinery of Matosinhos was facing difficulties in the production of base bitumens to be modified with copolymer of styrene-butadiene-syrene (SBS), namely with their storage stability. The crucial need to know the influence of the various bitumen components on the quality of the final product and their ability to prepare modified bitumens motivated the development of this industrial based PhD thesis. In order to understand the aforementioned problem, different bitumens were formulated with several components available in the Refinery. These bitumens were further modified with polyphosphoric acid (PPA) and/or a SBS copolymer. In addition to the components commonly used in the formulation of bitumen (asphaltic residue, vacuum residue, aromatic extract of SN-3) two other light aromatic extracts (SN-1 and SN-2) were identified as potential components to include in the formulation. The characterization of the different components was performed using standard techniques (penetration, softening point, penetration index, Fraass breaking point, ageing stability by Rolling Thin Film Oven Test - RTFOT), chemical characterization by SARA analysis (i.e. bitumen fractionation into Saturates, Aromatic, Resins and Asphaltenes) and 1H nuclear magnetic resonance (1H NMR) spectroscopy) and structural characterization (High Performance Gel Permeation Chromatography - HPGPC). The referred components were used to develop new formulations following a statistical design of mixtures (Mixture Design of Experiments - MDOE). A Scheffé quadratic model was adjusted to experimental values of penetration in order to obtain formulations that satisfy a penetration value of 100 dmm. The softening point was adjusted to a linear model, using the same methodology. Comparing both predicted and experimental set of values, the average absolute relative deviations (AARD) determined were 4.67% and 1.53% for penetration and softening point, respectively. Furthermore, to improve the bitumen consistency, i.e. to satisfy a penetration index between -1.5 and 0.7, the new formulations were treated with PPA (0.8 wt.%) and characterized using various techniques mentioned above. These formulations were also modified with SBS copolymer and characterized by standard methods (penetration, softening point, penetration index, and storage stability), HP-GPC and 13C NMR spectroscopy. The obtained results allowed to conclude that the use of light aromatic extracts (SN-1 or SN-1+SN-2 mixtures) improves the storage stability of modified bitumen, while the use of heavy aromatic extracts (SN-3) imparts a negative effect on it. The aromaticity and the molecular weight distribution of bitumens were pointed as major factors influencing the stability of SBS-modified bitumens. Within the framework of this thesis stable SBS-modified bitumens were prepared and it was concluded that to achieve stability they must possess both a polydispersity index between 2.26 and 2.44 and aromaticity higher than 45%. Since PPA is present in all formulations of the Refinery of Matosinhos, in order to decrease their penetration values and to meet the penetration index specifications, a complete bibliographic review on the effect of PPA on bitumen’s performance is presented. The effect of PPA on bitumens was analyzed experimentally, using standard characterization techniques, 31P and 1H NMR spectroscopy, and SARA analysis. The results demonstrated that PPA hydrolyze to phosphoric acid and reacts with bitumen modifying the proportions of the SARA fractions, namely, increasing the contents of asphaltenes and aromatics, and decreasing the contents of saturates and resins. The effects of the reactions with PPA improved the bitumen properties, particularly their consistency and thermal susceptibility. In conclusion, this PhD work has elucidated and solved the limitations of the Refinery of Matosinhos with regard to the production of modified bitumens for high value-added applications. Overall, this study identified new components for improved formulations and established a relationship between their properties and compositions (and of parent components), enabling their final modification with polymer, thus contributing substantially to the improvement of the product.
No início deste trabalho, a Refinaria de Matosinhos debatia-se com problemas relacionados com a produção de betumes base para posterior modificação com copolímero de estireno-butadieno-estireno (SBS), nomeadamente a sua estabilidade ao armazenamento. A necessidade fulcral de conhecer a influência dos vários componentes do betume na qualidade final do produto e a capacidade de preparar betumes modificados motivaram o desenvolvimento deste doutoramento de base empresarial. Para responder às solicitações anteriores, começou por estudar-se a formulação de betumes a partir de várias correntes disponíveis na refinaria, avançando-se depois para a sua modificação com ácido polifosfórico (PPA) e/ou com um copolímero de SBS. Para além dos componentes usualmente utilizados – resíduo asfáltico, resíduo de vácuo e o extrato aromático de SN-3 – identificaram-se dois extratos aromáticos, SN-1 e SN-2, com potencial para incorporação nas formulações. Efetuou-se a caracterização destes cinco componentes por métodos de análise previstos na especificação (penetração, temperatura de amolecimento, índice de penetração, temperatura de fragilidade de Fraass, estabilidade ao envelhecimento por Rolling Thin Film Oven Test - RTFOT), técnicas de caracterização química (fracionamento do betume em Saturados, Aromáticos, Resinas e Asfaltenos – análise SARA, e Ressonância Magnética Nuclear - RMN de 1H), e estrutural (Cromatografia de Permeação em Gel de Alta Eficiência - HP-GPC). Utilizando os componentes citados, desenvolveram-se formulações de betumes seguindo um planeamento experimental de misturas (Mixture Design of Experiments - MDOE). Seguidamente ajustou-se um modelo quadrático de Scheffé aos valores de penetração com o objetivo de estabelecer as formulações que satisfazem um valor de 100 dmm. A temperatura de amolecimento foi depois correlacionada com um modelo linear, seguindo a mesma metodologia. Os valores estimados face aos valores experimentais para os diferentes betumes apresentam um desvio relativo médio absoluto (AARD) de 4.67% e 1.53% para a penetração e temperatura de amolecimento, respetivamente. Adicionalmente, as formulações anteriores foram tratadas com PPA (0.8 %, m/m) para melhorar a consistência dos betumes, i.e., para satisfazerem a especificação do índice de penetração (entre -1.5 e 0.7), seguindo-se a respetiva caracterização com recurso às várias técnicas já referidas. As formulações foram ainda modificadas com SBS e caracterizadas por métodos padrão (penetração, temperatura de amolecimento, índice de penetração e estabilidade ao armazenamento) e ainda por HP-GPC e RMN de 13C. Os resultados obtidos permitiram concluir que o uso de extratos aromáticos leves (SN-1 ou mistura de SN-1 com SN-2) beneficia a estabilidade ao armazenamento dos betumes modificados, enquanto o uso de extratos aromáticos pesados (SN-3) provoca um efeito negativo. A aromaticidade e a distribuição das massas moleculares dos betumes foram apontadas como fatores cruciais para a estabilidade dos betumes modificados com SBS. No âmbito desta dissertação foram preparados betumes modificados com SBS estáveis, tendose concluído que devem possuir simultaneamente um índice de polidispersidade entre 2.26 e 2.44 e aromaticidade superior a 45%. Paralelamente, e uma vez que o PPA é uma presença constante nas formulações para se atingir o índice de penetração da especificação, efetuouse uma revisão bibliográfica sobre a influência do PPA nos betumes e realizouse um estudo experimental para analisar o efeito deste ácido sobre o desempenho dos betumes estudados. Para além das técnicas de caracterização convencionais de betumes já mencionadas, foram ainda incluídas a espectroscopia de RMN de 31P e de 1H, e a análise SARA. Os resultados obtidos permitiram verificar que o PPA hidrolisa a ácido fosfórico e reage com o betume, provocando uma alteração da distribuição das frações SARA, nomeadamente, um aumento das frações de asfaltenos e aromáticos e uma diminuição das frações de resinas e saturados. Estes efeitos da reação com o PPA melhoram as propriedades do betume, particularmente a sua consistência e a suscetibilidade térmica. Em conclusão, este trabalho de doutoramento permitiu esclarecer e resolver as limitações existentes inicialmente na Refinaria de Matosinhos no que concerne à produção de betumes modificados para aplicações de elevado valor acrescentado. No cômputo geral, os estudos desenvolvidos permitiram identificar novas correntes com elevado potencial de aplicação para produzir betumes melhorados, estabelecer uma relação entre as propriedades dos betumes e a sua composição (e a dos seus componentes), tornando possível no final efetuar a sua modificação com polímero, contribuindo substancialmente para a melhoria do produto.
Programa Doutoral em Engenharia da Refinação, Petroquímica e Química

Flotation process is mineral processing technique used for separating valuable minerals from the gangue. The research presented in this thesis deals with assessing features that can help in measuring the performance (observing) bitumen flotation process and modeling damage in flotation units. A timely measure of oilsands and process stream contents can be used to observe and control the separation performance. To this end, flotation experiments were conducted and hyperspectral images of the ore and the process stream were taken to determine whether spectral information can predict the bitumen and fines content of ore samples and establish relationship a between these variables and the froth colour. Several features that appear to correspond to clay and quartz were present. Flotation cells are prone to wear damage by particles entrained in the slurry. A wear damage model was developed to predict the damage accumulated over a period of time. Particle image velocimetry experiments were conducted on physical flotation model to understand the flow behavior of the solid particles near the wall of the flotation unit. A preliminary wear test was conducted for qualitative assessment of wear. Recommendations were made for validating the damage model.
Engineering Management

Thesis (Ph. D.)--Florida State University, 2007.
Advisor: Alan Marshall, Florida State University, College of Arts and Sciences, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Mar. 11, 2008). Document formatted into pages; contains xxiii, 175 pages. Includes bibliographical references.

no
In contrast with artefactual studies of long-distance trade and exchange in South Asia during the Prehistoric and Early Historic periods (Ardika et al . 1993; Gogte 1997; Krishnan and Coningham 1997; Tomber 2000; Gupta et al . 2001; Ford et al . 2005), few scientifically orientated analyses have focused on artefacts from the region¿s Historic period. During excavations at the ancient city of Anuradhapura, Sri Lanka, a number of buff ware ceramics with a putative organic coating on the interior were recovered (Coningham 2006). Dated stylistically to between the third and ninth centuries AD , analysis of the coatings using gas chromatography¿mass spectrometry (GC¿MS) and stable isotope analysis (carbon and deuterium) confirmed that the coatings are bitumen¿an organic product associated with petroleum deposits. There are no known bitumen sources in Sri Lanka, and biomarker distributions and isotopic signatures suggest that the majority of the samples appear to have come from a single bitumen source near Susa in Iran. The relationship between the bitumen coatings and the vessels is discussed, and it is suggested that the coatings were used to seal permeable ceramic containers to allow them to transport liquid commodities. This study enhances our knowledge of networks of trade and exchange between Sri Lanka and western Asia during Historic times.

This report offers a comparative valuation of two bitumen production technologies, using real options analysis (ROA) techniques to incorporate strategic flexibility into the investment scenario. By integrating a probabilistic cost model into a real options framework, the value of an oil recovery facility is modeled to reflect the realistic alternatives available to decision-makers, where the course of the investment can be altered as new information becomes available. This approach represents a distinct advantage to traditional discounted cash flow (DCF) estimation, which is unable to capture operational adaptability, including the ability to expand, delay, or abandon a project. The analysis focuses on the energy inputs required for the recovery of heavy oil bitumen from Alberta, Canada, and examines both natural gas and nuclear steam plants as heat sources. The ACR-1000 reactor is highlighted as a substitute for conventional natural gas-fueled means of production, in light of the recent volatility of natural gas prices and the potential for emissions compliance charges. The methodology includes a levelized cost assessment per barrel of bitumen and estimation of cost ranges for each component. A mean-reversion stochastic price model was also derived for the both natural gas and oil price. By incorporating cost ranges into a ROA framework, the benefit of retaining project flexibility is included in its valuation. Formulated as a decision tree, built-in options include the initial selection to pursue nuclear or natural gas, site selection and licensing, the ability to switch heat source in the planning stage, and the final commitment to construct. Each decision is influenced by uncertainties, including the course of bitumen and natural gas price, as well as emissions policy. By structuring the investment scenario to include these options, the overall value of the project increases by over $150 million. The ability to switch technology type allows for an assessment of the viability of nuclear steam, which becomes economically favorable given high natural gas prices or high emissions taxes. Given an initial selection of natural gas SAGD, there is a 25% probability that a switch to nuclear steam will occur, as evolving financial conditions make nuclear the optimal technology.
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Yes
Transport and storage vessels in Red Lustrous Wheelmade ware (RLWm ware) were traded across a large area of the eastern Mediterranean for approximately 300 years (c. 1500–1200 BCE) during the Late Bronze Age (c.1600–1000 BCE). The extreme consistency of the ceramic, in form, fabric, chemistry and mineralogy, points to a single production source for the ware, which, although no kiln sites have been identified, is generally accepted to have been on Cyprus. The aim of this study was to determine whether organic residues were present in this very fine, dense ware, and to characterise the contents of RLWm ware vessels from different sites, contexts and periods, and of different forms, to improve our understanding of the trade in this ceramic type. To that end, 101 RLWm ware sherds, together with three visible residues, were examined from sites in Turkey, Cyprus, Egypt and Syria. Residues were identified in more than half of the samples, indicating that organic material is absorbed into and preserved in this very fine fabric. Four commodities were identified: fat (probably plant oil), which in four residues was identified further as castor oil; beeswax; bitumen; and Pinaceae spp. resin. The commodities were found alone or, occasionally, one of the latter three was combined with the fat or oil. Fatty material was the only commodity present at all sites and its wide distribution may indicate that generally the vessels were used for a mixture or mixtures based on plant oils, in some cases containing castor oil. It was impossible to determine whether the beeswax, bitumen and resin formed part of this mixture or represented post-firing treatments of the ceramic to make it less porous. The identification of more than one type of residue indicates that RLWm ware vessels did not always contain the same commodity. No significant correlation could be detected between the vessel forms, and the dating of many of the sherds was not precise enough to reveal any variation through time. The type of residue present did vary depending on the geographical location of its final use. Beeswax was, with two exceptions, only present in samples from Turkey, while bitumen was found exclusively in samples from Cypriot sites. The occurrence of at least one example of every commodity in the samples from Cyprus is consistent with the theory that this ware was manufactured on Cyprus, and indicates that the vessels could also have been filled and exported from there. The variation in content of the vessels found in different geographical areas could highlight a special trading relationship between the Hittite heartland in Turkey and the Cypriot potters who produced the ware, and a possible trade in bitumen as a raw material between the north Syrian coastal area of Ugarit and Cyprus.
This research was funded by an AHRC PhD studentship (number 110786), awarded to V. Steele.

Phase behaviour information is essential for the development and optimization of hydrocarbon resource production, transport and refining technologies. Experimental data sets for mixtures containing heavy oil and bitumen are sparse as phase behaviour data are difficult to obtain and cost remains prohibitive for most applications. A computational tool that predicts phase behaviours reliably for mixtures containing such ill-defined components, over broad temperature, pressure and composition ranges would play a central role in the advancement of bitumen production and refining process knowledge and would have favourable impacts on the economics and environmental effects linked to the exploitation of such ill-defined hydrocarbon resources. Prior to this work, predictive computational methods were reliable for dilute mixtures of ill-defined constituents. To include a much wider range of conditions, three major challenges were addressed. The challenges include: creation of a robust and accurate numerical approach, implementation of a reliable thermodynamic model, and speciation of ill-defined constituents like Athabasca Bitumen Vacuum Residue (AVR). The first challenge was addressed by creating a novel computational approach based on a global minimization method for phase equilibrium calculations. The second challenge was tackled by proposing a thermodynamic model that combines the Peng-Robinson equation of state with group contribution and related parameter prediction methods. The speciation challenge was addressed by another research group at the University of Alberta. Pseudo components they proposed were used to assign groups and estimate thermodynamic properties. The new phase equilibrium computational tool was validated by comparing simulated phase diagrams with experimental data for mixtures containing AVR and n-alkanes. There is good qualitative and quantitative agreement between computed and experimental phase diagrams over industrially relevant ranges of compositions, pressures and temperatures. Mismatch was only observed over a limited range of compositions, temperatures and pressures. This computational breakthrough provides, for the first time, a platform for reliable phase behaviour computations with broad potential for application in the hydrocarbon resource sector. The specific computational results can be applied directly to solvent assisted recovery, paraffinic deasphalting, and distillation and refining processes for Athabasca bitumen a strategic resource for Canada.
Chemical Engineering

Tese de Doutoramento em Engenharia Civil
As novas metas ambientais no que concerne à conservação dos recursos naturais e à valorização de resíduos têm servido de motivação para vários estudos científicos de diferentes áreas de investigação. Nesse sentido, no domínio da indústria da pavimentação rodoviária, que consome imensos recursos naturais, tem sido investigada a incorporação de diferentes resíduos em misturas betuminosas de modo a desenvolver soluções mais sustentáveis. Sendo o betume um dos materiais mais valiosos utilizados na pavimentação é fundamental o estudo de novos ligantes que permitam reduzir a quantidade de betume novo utilizado, quer pela reutilização de betume envelhecido (reciclagem), quer pela adição de alguns resíduos, pelas vantagens económicas e ambientais associadas. Deste modo, o principal objetivo deste trabalho consiste em desenvolver betumes inovadores que maximizem a utilização de resíduos, particularmente óleo de motor usado e fundo de coluna de destilação (substitutos parciais do betume), para a produção de misturas betuminosas convencionais e recicladas mais sustentáveis. Este trabalho pretende assim desenvolver novas soluções para pavimentação, que aliem o desempenho técnico e a viabilidade económica aos benefícios ambientais que resultam da utilização de resíduos industriais e material fresado em misturas betuminosas. Adicionalmente, pretende garantir-se que estas soluções com elevada incorporação de resíduos não apresentem riscos associados à sua utilização, quer ao nível dos seus lixiviados, quer das suas emissões de dióxido de carbono. Para a concretização deste trabalho, foi realizada a caracterização térmica, química e física dos diferentes materiais a utilizar nos betumes modificados com resíduos e nas misturas betuminosas. Além disso, de modo a verificar a dispersão do polímero no betume com óleo de motor usado, foram avaliados através de microscopia de fluorescência diferentes procedimentos de produção dos betumes modificados. Desta forma, foi possível minimizar o tempo e/ou a temperatura de digestão e obter uma dispersão mais eficaz do polímero no betume com óleo de motor usado. Em seguida, os betumes modificados com várias percentagens dos diferentes resíduos (óleo/fundo de coluna e polímeros) foram avaliados através de ensaios de caracterização básica e reológica, tendo sido selecionados aqueles cujas características foram mais promissoras. Os betumes selecionados foram ainda avaliados a nível térmico, químico e quanto à resistência ao envelhecimento. Em seguida, foram produzidas misturas convencionais e recicladas do tipo Stone Mastic Asphalt (SMA) com estes betumes inovadores modificados com resíduos, que foram avaliadas quanto ao seu desempenho mecânico e superficial. Finalmente, a sustentabilidade destas soluções foi analisada no que respeita à produção de lixiviados, emissões de dióxido de carbono, e quanto à sua viabilidade económica. Os resultados deste estudo confirmam que os betumes inovadores modificados com resíduos desenvolvidos neste trabalho permitem produzir misturas convencionais e recicladas mais sustentáveis, que aliam um bom desempenho mecânico com benefícios económicos e ambientais. Estes betumes modificados com resíduos exibem menor suscetibilidade térmica, sendo mais resistentes à deformação permanente a elevadas temperaturas e mais flexíveis a temperaturas mais baixas. Quando utilizados nas misturas betuminosas, a maioria dos betumes modificados com resíduos aumenta a resistência à ação da água, à deformação permanente e ao fendilhamento por fadiga, sem comprometer as características superficiais das misturas. Apesar de se ter desenvolvido neste trabalho vários ligantes inovadores mais sustentáveis do que o betume convencional, aqueles que apresentam os resultados mais promissores a nível mecânico, económico e ambiental são os betumes modificados com resíduos de polietileno de alta densidade e óleo de motor usado ou fundo de coluna. De facto, ao comparar estruturas de pavimentos com um desempenho equivalente, as misturas com estes ligantes apresentam em geral os custos e as emissões de dióxido de carbono mais baixos de todas as soluções analisadas.
The new environmental targets related to conserving the natural resources and recovering the waste materials have been the basis for several scientific studies in different research areas. Therefore, in the road paving industry field, which consumes massive amounts of natural resources, the incorporation of different waste materials in asphalt mixtures has been investigated in order to develop more sustainable solutions. As bitumen is one of the most valuable materials used in pavements, the study of new binders that incorporate a lower amount of new bitumen is essential, both by reusing aged bitumen (recycling) and by adding some waste materials, due to the associated economic and environmental advantages. Thus, the main aim of this study is the development of innovative modified bitumens that maximize the use of waste materials, especially waste engine oil and recycled engine oil bottoms (partial replacements for bitumen), to produce more sustainable conventional and recycled asphalt mixtures. With this work, new solutions for road paving materials, combining adequate performance and economic viability with environmental advantages that result from the use of industrial waste and reclaimed asphalt materials in asphalt mixtures, shall be developed. Ultimately, this work should assure that these solutions with high incorporation of waste materials do not present risks related to their use, either from their leachates or from their carbon dioxide emissions. For the accomplishment of this work, thermal, chemical and physical characterisation of the materials used in the modified bitumens with waste materials and in the asphalt mixtures was carried out. Additionally, different bitumen modification procedures were evaluated through fluorescence microscopy tests to verify the polymer dispersion in the blend of bitumen and waste engine oil. Thus, it was possible to minimize the digestion time and/or temperature and to obtain a more effective polymer dispersion in the blend of bitumen and waste engine oil. Afterwards, several modified bitumens with different amounts of waste materials (waste engine oil/recycled engine oil bottoms and polymers) were evaluated through basic and rheological characterization, and those with the most promising properties were selected. The selected bitumens were further characterised regarding their thermal, chemical and aging resistance behaviour. Then, conventional and recycled Stone Mastic Asphalt (SMA) mixtures produced with those innovative bitumens modified with waste materials were evaluated regarding their mechanical and surface performance. Finally, the sustainability of these solutions was analysed in relation to their leachates production, carbon dioxide emissions and economic viability. The results from this study confirm that the innovative bitumens modified with waste materials developed in this work are able to produce more sustainable conventional and recycled asphalt mixtures, which combine a good mechanical performance with economic and environmental benefits. These binders present lower thermal susceptibility, being more resistant to permanent deformation at high temperatures and more flexible at lower temperatures. When used in asphalt mixtures, the majority of the bitumens modified with waste materials increases the water sensitivity, permanent deformation and fatigue cracking resistances, without compromising their surface characteristics. Although several innovative binders that are more sustainable than the conventional bitumen have been developed in this study, those modified with waste high density polyethylene and waste engine oil or recycled engine oil bottoms have presented the most promising results at the mechanical, economic and environmental levels. Indeed, when comparing pavement structures with equivalent performance, the asphalt mixtures with these modified bitumens have generally shown the lowest costs and carbon dioxide emissions amongst all analysed solutions.
Este trabalho foi financiado pelo Governo de Portugal e pelo Fundo Social Europeu da União Europeia (EU/FSE), através da Fundação para a Ciência e Tecnologia (FCT), através de uma Bolsa de Doutoramento SFRH/BD/98379/2013, e no âmbito do Programa Operacional Potencial Humano inscrito no Quadro de Referência Estratégico Nacional (POPH/QREN).