Asphalt materials exhibit self-healing characteristics. In order to evaluate the healing capabilities of these materials, numerous investigations are carried out by researchers. These investigations include various definitions of healing and mechanical test methods to quantify the extent of healing. Irrespective of these extensive studies, there is no unique method to evaluate the healing in asphalt materials. The biasedness to the test conditions and complexity due to the involvement of other phenomena such as stress relaxation and strain recovery make the characterization of healing a challenging process. The work presented in this thesis includes the development of experimental and analytical approaches to contribute to the understanding of healing in asphalt materials. The thesis focuses on both fracture mechanics and damage mechanics-based approaches to evaluate the healing in asphalt materials. In the first case, three-point bending tests are carried out to characterize the healing following the fracture. The experimental protocol is carefully designed to avoid the effect due to low temperature physical hardening of the material during the rest period. Different healing indices appealing to linear elastic fracture mechanics and viscoelastic fracture mechanics are compared. While healing is generally defined based on the recovery of certain parameters following the rest period, the comparison across healing indices shows that the quantitative interpretations of healing are dependent on the post-processing methods. The damage mechanics-based approach discussed in this study includes creep and recovery tests in shear. Here, unlike the first case, the samples are not fractured during the test. The damage is considered to be a part of the viscoplastic deformation and the recovery of viscoplastic deformation is defined as the healing. The method proposed in this study is useful to isolate the viscoelastic effects to quantify the healing of damage. / Asfaltmaterial uppvisar självläkande egenskaper. För att utvärdera dess läkande förmågor utförs många undersökningar av forskare. Dessa undersökningar inkluderar olika definitioner av läkning och mekaniska testmetoder för att kvantifiera graden av läkningen. Trots dessa omfattande studier finns det ingen unik metod för att utvärdera läkning i asfaltsmaterial. Påverkan av testförhållandena och komplexiteten från inverkan av andra fenomen, såsom spänningsrelaxation och töjningsåterhämtning, gör karakteriseringen av läkning en utmanande process. Arbetet som presenteras i denna uppsats inkluderar utvecklingen av experimentella och analytiska metoder för att bidra till förståelsen av läkning i asfaltsmaterial. Uppsatsen fokuserar på både brottmekaniks- och skademekaniksbaserade metoder för att utvärdera läkning i asfaltsmaterial. I det första fallet utförs trepunktsböjningstest för att karakterisera läkningen efter brott. Det experimentella protokollet är noggrant designat för att undvika effekten av hårdnande vid låg temperatur under viloperioden. Dessutom jämförs olika läkningsindex baserade på linjärelastisk brottmekanik och viskoelastisk brottmekanik. Trots att läkning generellt definieras baserat på återhämtningen av vissa parametrar efter viloperioden, så visar jämförelsen av läkningsindexen att den kvantitativa tolkningen av läkning beror på metoderna för efterbehandling.  Den skademekaniksbaserade metoden som diskuteras i denna studie inkluderar kryp- och återhämtningstest i skjuvning. Till skillnad mot det första fallet så spricker här inte proven. Skadan anses istället vara del av den viskoplastiska deformationen och återhämtningen av viskoplastisk deformation är definierad som läkning. Metoden som föreslås i denna studie är användbar för att isolera de viskoelastiska effekterna för att kvantifiera läkningen av skada.

Des polyuréthanes thermoplastiques (TPU) contenant des segments rigides et segments souples d’architecture moléculaire variable sont synthétisés en deux étapes, dont la première fait intervenir un pré-polymère polyuréthane. La microstructure de ces polymères montre qu’une séparation de phases intervient entre segments souples et rigides selon la nature des segments utilisés. Les segments rigides peuvent s’organiser sous deux formes, l’une amorphe et l’autre organisée sous forme d’entités cristallines. La morphologie des TPU dépend de la structure chimique du segment rigide employé. L’incompatibilité entre segments souples et rigides a été mise en évidence à partir de l’analyse des paramètres de solubilité complétée des caractérisations à différentes échelles par des techniques de microscopie (électronique et AFM) et de diffusion des rayons X. Ces polyuréthanes thermoplastiques sont ensuite utilisés pour préparer des mélanges bitume –polymère. Les interactions entre segments du polymère et fractions du bitume sont étudiées en considérant les paramètres de solubilité de chacun d’eux et des mesures de gonflement afin de juger de la miscibilité entre les composés. Des huiles modèles sont employées dans le but de mimer certaines fractions huileuses du bitume, et les segments souples et rigides sont synthétisés séparément afin d’étudier les propriétés de chacune des phases en présence dans le mélange bitume – polymère. La morphologie multi-échelle des mélanges est étudiée en lien avec les propriétés rhéologiques et la structure du polymère utilisé. L’ajout de polymère dans le bitume permet de modifier les propriétés viscoélastiques du bitume au-delà de sa transition vitreuse grâce au gonflement sélectif du polymère par les fractions huileuses. Après avoir mis en évidence et analysé le gonflement sélectif grâce à la prise en considération des paramètres de solubilité et mesuré les tensions interfaciales, nous montrons que la présence d’une phase continue riche en polymère contenant des segments rigides semi-cristallins dans les mélanges conduit à retarder l’écoulement du matériau bitumineux à plus hautes températures. La composition en huile de cette phase riche en polymère dépendra de son affinité avec les fractions du bitume et donc de la structure chimique du polymère. De plus, la teneur du polymère en segments rigides semi-cristallins est aussi un levier permettant d’intervenir sur son affinité avec le bitume et par conséquent sur les propriétés rhéologiques du mélange bitume-polymère. / Thermoplastic polyurethane (TPU) containing hard and soft segments with variable molecular architecture are synthesized in two steps, the first one including a polyurethane pre-polymer. The microstructure of theses polymers shows phase separation occurring between soft and hard segments according to the nature of the segments. Hard segments can organize under two forms, either amorphous or crystalline. The morphology of TPU depends on the chemical structure of the hard segment involved. Incompatibility between soft and hard segments was highlighted from solubility parameters analysis, complete with characterization at various scales with microscopy (electron and AFM) and X-ray scattering technics. Theses thermoplastic polyurethanes are used to prepare bitumen-polymer blends. Interactions between the polymer segments and bitumen fractions are studied, considering solubility parameters of each of them and swelling measurements in order to study miscibility between the compounds. Model oils are used in the aims of mimicking some oily fractions of bitumen, and soft and hard segments are separately synthesized to study properties of each phases in the bitumen-polymer mixture. Multi-scale morphology of the blends is studied in connection with rheological properties and structure of the used polymer. The addition of polymer in bitumen allows to modify viscoelastic properties of bitumen beyond its glass transition due to the selective swelling of the polymer by the oily fractions. Having highlighted and analyzed the selective swelling by considering solubility parameters and interfacial tension measurements, we show that the presence of a continuous polymer-rich phase containing semi-crystalline hard segments in the blends leads to delay the flow of the bituminous material at highest temperatures. The oil composition of this polymer-rich phase will depend on its affinity with the fractions of bitumen and thus on the chemical structure of the polymer. In addition, semi-crystalline hard segment content of the polymer is also a key parameter allowing to adjust its affinity with bitumen and consequently on rheological properties of the bitumen-polymer mixture.

Under våren 2021 upptäcktes förhöjda halter av polyaromatiska kolväten (PAH) i Björklinges dricksvattennät. Då ett vattenprov taget hos användare påvisade halter som låg över Livsmedelsverkets gränsvärden och källan till föroreningen inte identifierats, rekommenderades hushållen i Björklinge att inte använda kranvattnet till mat och dryck under en period. Efter sektionering av nätet och provtagning identifierades en äldre, nyligen reparerad, ledningssträcka av gjutjärn som trolig föroreningskälla. Denna typ av ledning är relativt vanligt förekommande i delar av Uppsala Vattens nät. Syftet med denna studie var att få en djupare förståelse för orsakerna till PAH-föroreningen i Björklinge och bedöma risken för att liknande föroreningar ska hända igen, samt att tillhandahålla ett beslutsunderlag för Uppsala Vattens hantering av äldre gjutjärnsledningar.En litteraturstudie genomfördes och data från Björklinge analyserades. Resultaten av litteraturstudien visade att frisättning av PAH från äldre gjutjärnsrör med korrosionsskydd innehållande stenkolstjära eller bitumen är ett välkänt fenomen. Biofilmen har en skyddande effekt och graden av frisättning kan därför påverkas av faktorer som klorering eller syrehalt i vattnet. Även mekaniskt slitage i form av reparationsarbete och tryckvågor kan leda till förhöjda nivåer av PAH. Korrosion av ledningarna är troligen också en viktig faktor.Utifrån litteraturstudien och resultaten från användarprover tagna i Björklinge respektive Skuttunge kunde det konstateras att problemen i Björklinge hade ett samband med frisättning av PAH från gjutjärnsrör. Vid tidpunkten för studien kunde ökande PAH-halter observeras på vissa platser i ledningsnätet även efter ledningsbytet i Björklinge våren 2021, vilket tydde på fortsatt kontaminering. Inga uppmätta halter i användarprover låg dock över något av Livsmedelsverkets gränsvärden och PAH i dricksvattnet anses inte vara ett stort hälsomässigt problem i dagsläget. Det är däremot viktigt att fortsätta monitorera halterna av PAH i Uppsala Vattens nät då denna typ av problem kan uppstå igen. Man bör också vara försiktig med åtgärder som kan påverka biofilmen samt vara återhållsam med spoling av denna typ av ledningar. De ledningar som identifierats som föroreningskällor bör åtgärdas. Med tanke på ledningarnas stigande ålder, begränsad kunskap om PAH och dess hälsoeffekter, samt WHOs rekommendationer bör man dock initiera ett långsiktigt arbete med att byta ut eller renovera denna typ av ledningar i Uppsala Vattens nät. / During the spring of 2021 elevated levels of polyaromatic hydrocarbons (PAH) were discovered in the drinking water supply network of Björklinge. Levels above the limit set by the Swedish Food Agency were observed in one user sample, which led to the inhabitants of Björklinge being recommended not to use the tap water for drinking or cooking while the source of the contamination was being identified. After sectioning and sampling the network, an older, recently repaired cast iron pipe was identified as the probable source of the contamination. This type of pipe is not uncommon in the drinking water network of Uppsala Vatten. The purpose of this study was to gain a deeper understanding of the causes of the PAH contamination in Björklinge and to determine the risk of similar contaminations happening again. Further, it aimed to provide a basis for future decisions regarding the handling of older cast iron pipes in the drinking water network of Uppsala Vatten.A literature study was done and data from Björklinge was analysed. The results of the literature study showed that the release of PAH from older cast iron pipes with coal tar or bitumen coating is a well-known phenomenon. The biofilm has protective properties, and the degree of PAH release can hence be affected by factors such as chlorination or oxygen concentration of the water. Mechanical wear in the form of repair work or pressure waves can also cause increased levels of PAH in the water.Based on the literature study as well as the results from the user samples of Björklinge and Skuttunge, it could be determined that the PAH contamination in Björklinge was related to the release of PAH from old cast iron pipes. At the time of this study, increasing levels of PAH could be observed in some parts of the drinking water network even after the suspected pipes had been replaced during the spring of 2021. This might indicate that the contamination was still ongoing. However, no samples were above the limits set by the Swedish Food Agency and PAH is currently not considered a major health problem. Despite this, it is important to keep monitoring the levels of PAH in the drinking water since the PAH levels might increase again. It is also important to be careful with measures that might affect the biofilm and when flushing cast iron pipes. The pipes that have already been identified as sources of contamination should be replaced. Given the increasing age of the cast iron pipes, the limited knowledge of PAH and its health effects, as well as the recommendations from the WHO, a long-term plan for how to remove or renovate this type of pipes from the drinking water network of Uppsala Vatten should be initiated.

Thesis(PhD (Civil Engineering))-- University of Stellenbosch, 2004. / ENGLISH ABSTRACT: Bitumen based road surfacing seals and asphalt wearing courses have been used by society's Engineers "to counter the damage to the existing unsurfaced roadways by the newly developed automobile with its rubber driving wheels" since the early 1900's. Early experiments were conducted with both tar and bitumen to find a suitable material to alleviate the situation, and ongoing research has been carried out through the past century and into the new millennium, throughout the world, examining improvements, from materials used, to design and construction methods. However, there is still much to be understood, improved and refined, when considering road surfacing seal design. Pavement designers have the choice of utilizing either an asphalt (graded aggregate remanufactured with a bitumen binder and applied as a complete product) or a surfacing seal (including variations of bitumen binder sprayed onto the road surface, with the addition of single size stones, either in one or two layers of binder and aggregate, i.e. single or double seals) as a pavement wearing course. Current road surfacing seal design practice depends on empirical analysis and experience, being primarily a volumetric based assessment of bitumen application. This research project assesses South African seal design philosophy, investigates design areas where review or updating is required to accommodate changing bitumen sources and types, and traffic loading. Seal performance criteria are examined, with the development of a matrix of influences on seal performance. Using this, the need for a seal design method based on mechanistic material properties is proposed, and the prototype example of such a numerical model using finite element method is presented. To contribute further towards a performance related seal design method, the feasibility of modelling of road surfacing seals using mechanistic principles was examined. The potential of developing failure and fatigue criteria or relationships to enable assessment of the expected seal performance, with inclusion of different component material characteristics and variations, varying traffic and environmental conditions, was also examined. From assessment of literature, and understanding of the components of the seal, pavement, and influencing factors, a choice of numerical model of seal performance was made. The Finite Element Method (FEM) Analysis was selected for the purpose of modelling seal performance. The model was developed to enable examination of the interaction of individual seal components (i.e. stone and bitumen), at micro-mechanic scale. The prototype 3-dimensional numerical seal model was undertaken in 2002 and 2003 at Technical University Delft, using the CAPA research program. On the basis of the linear calculations the developed numerical prototype model is able to provide insight into seal behaviour and distinction between mechanical (seal geometry) and chemical (components) seal aspects, and insight into stress and strain development in the different seal types. Simulations of different seal, environmental and traffic scenarios are provided to demonstrate the potential of the model (excluding seal aggregate interlock and embedment effects at prototype stage). In order to provide data for the verification of the prototype numerical model, and to further contribute to the development of a performance related seal design method, performance tests were developed, with a new tool for assessment of comparative seal performance using the Model Mobile Load Simulator Accelerated Pavement Testing apparatus. The performance of each different seal binder type - Penetration grade Mumen, SBS, SBR, EVA and Bitumen Rubber - was undertaken. A methodology for the assessment of in-service seal performance was developed, and the performance of the respective seals reported. The results of this examination showed that each binder type has its unique contribution to seal performance. These new performance tests will be able to assist designers in the added determination of the fundamental binder properties on seal performance, and the seals' ability to contribute to the overall performance of the pavement. An additional comparative performance test method was developed to enable assessment of the effect of ageing and moisture, to complement the MMLS results. In summary, the performance testing has assisted in identifying the critical parameters a seal designer should consider during the design process. From this research, it is evident that the current seal design method requires further development to able designers to predict the effect of: Varying axle loads, tyre pressures and design speed; Varying characteristics of the different binders, (i.e. temperature - viscosity relationships, adhesion and visco-elastic behaviour); on the performance of seals. The major areas for suggested improvement in current seal design methods towards a performance based design method are: inclusion of variable traffic load and environmental characteristics, including temperature and moisture influences, and inclusion of mechanistic material characteristics into the design methodology. / AFRIKAANSE OPSOMMING: Bitumengebaseerde padoppervlakseellae en asfaltslytlae is sedert die 1900's deur ingenieurs gebruik as teenwig teen die skade wat die pas ontwikkelde voertuig met sy rubberwiele aan bestaande ryvlakke sonder oppervlakbehandeling aangerig het. In vroeëre eksperimente wat daarop gemik was om 'n geskikte materiaal te vind om die probleem teen te werk, is 'n kombinasie van teer en bitumen gebruik. Sedertdien word voortgesette navorsing steeds wêreldwyd gedoen om verbeterings te ondersoek, nie net ten opsigte van materiale nie maar ook ontwerp- en konstruksiemetodes. Wat die ontwerp van padoppervlakseëling betref is daar egter heelwat wat reg begryp, verbeter en verfyn moet word. Plaveiselontwerpers het die keuse om of 'n asfalt te gebruik (gegradeerde aggregaat voorafvervaardig met 'n bitumen bindmiddel en aangewend as 'n klaarproduk), of 'n oppervlakseël (een laag of twee lae [m.a.w. enkel- of dubbelseël] bitumen bindmiddel met aggregaat [enkelgrootte klippies] bygevoeg, gespuit op die padoppervlak). In die praktyk berus die ontwerp van padoppervlakseëling tans op empiriese analise en ervaring (wat hoofsaaklik 'n volumetriesgebaseerde assessering van die aanwending van bitumen is). Hierdie navorsingsprojek doen 'n waardebepaling van die Suid-Afrikaanse filosofie van seëlontwerp, en ondersoek ontwerpterreine wat hersiening of bywerking benodig om vir veranderende bitumenbronne en -tipes, asook verkeerslading, voorsiening te maak. Met die ontwikkeling van 'n matriks van die invloede op seëlprestasie is die kriteria vir seëlprestasie ondersoek. Op grond daarvan word aangevoer dat daar 'n behoefte is aan 'n seëlontwerpmetode gebaseer op die meganistiese eienskappe van materiaal, en word 'n voorbeeld van 'n numeriese modelprototipe wat die eindige-element-metode gebruik, voorgelê. Ten einde 'n verdere bydrae te lewer tot die ontwikkeling van 'n prestasiegerigte seëlontwerpmetode, is die uitvoerbaarheid van die modellering van padoppervlakseëllae gebaseer op meganistiese beginsels, ondersoek. Daar is ook ondersoek ingestel na die potensiaal vir die ontwikkeling van kriteria vir die vasstel van mislukking en vermoeidheid of verhoudinge wat die assessering van die verwagte seëlprestasie (ingesluit die verskillende kenmerke en variasies van seëlkomponentmateriaal en wisselende verkeers- en omgewingsomstandighede) moontlik kan maak. Met oorweging van die bestudeerde literatuur en 'n begrip van die komponente van seël, plaveisel en inwerkende faktore, is 'n keuse van 'n numeriese model vir seëlprestasie gemaak. Die eindige-element-metode (Finite Element Method [FEM]) is gekies as die analitiese metode vir die modellering van seëlprestasie. Die model is ontwikkel om die ondersoek van die interaksie tussen individuele seëlkomponente (klip en bitumen) op mikromeganiese skaal moontlik te maak. Die ontwikkeling van die driedimensionele, numeriese, model-seëlprototipe is tussen 2002 en 2003 by die Delft Tegniese Universiteit gedoen, met gebruikmaking van die CAPA-navorsingsprogram. Wat lineêre berekenings betref, kan die ontwikkelde numeriese modelprototipe 'n insig gee in seëlgedrag en in die onderskeid tussen aspekte van seëlgeometrie (meganies) en seëlkomponente (chemies), asook in die spanning- en vervormingsontwikkeling van die verskillende tipes seël. Simulasies van verskillende seël-, omgewings- en verkeerscenario's word voorgestel om die potensiaal van die modelprototipe te demonstreer. Met die oog daarop om data vir die verifikasie van die numeriese modelprototipe te voorsien, en om verder tot die ontwikkeling van 'n prestasiegerigte seëlontwerpmetode by te dra, is prestasietoetse, met 'n nuwe instrument vir die assessering van vergelykende seëlprestasie met behulp van die Model Mobile Load Simulator Accelerated Pavement Testing apparaat, ontwikkel. Die prestasie van elke verskillende tipe seëlbindmiddel- penetrasiegraad bitumen, SBS, SBR, EVA en bitumenrubber - is getoets. 'n Metodologie vir die assessering van die ingebruiksprestasie van seëllae is ontwikkel, en daar is verslag gedoen oor die prestasie van die verskillende seëllae. Die resultate van die ondersoek het getoon dat elke tipe bindmiddel 'n eie unieke bydrae tot die prestasie van die seël lewer. Die nuwe prestasietoets sal ontwerpers help met die bepaling van die grondliggende bindmiddeleienskappe wat by seëlprestasie ter sprake is, asook van die seël se vermoë om tot die algehele prestasie van die plaveisel by te dra. 'n Bykomende prestasievergelykingstoetsmetode vir die assessering van die effek van veroudering en vogtigheid is ontwikkel om die MMLS-resultate aan te vul. Ter opsomming, die prestasietoetsing het bygedra tot die identifisering van die kritiese parameters wat die seëlontwerper tydens die ontwerpproses in gedagte behoort te hou. Die navorsing wat gedoen is, dui daarop dat die huidige seëlontwerpmetode verder ontwikkel moet word om ontwerpers in staat te stel om die effek van die volgende te kan voorspel: Wisselende aslas, banddruk en ontwerpspoed; Verskillende kenmerke van die verskillende bindmiddels (bv. temperatuur viskositeitsverhoudinge, vashegting en viskoëlastiese gedrag). Wat huidige seëlontwerpmetodes betref, is die hoofterreine waarop 'n verbetering voorgestel word, die insluiting van veranderlike verkeerslas- en omgewingskenmerke, ingesluit die invloed van temperatuur en vogtigheid, en insluiting van meganistiese kenmerke van materiaal in die ontwerpmetodologie.

Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Factors influencing surface run-off of bitumen emulsions were studied in order to understand binders for use in the construction of surfacing seals. Run-off of the binder from the road surface causes an inconsistent film thickness leading to ravelling (Johannes, Hanz & Bahia n.d.) and bleeding at the upstream and downstream regions, respectively. There is currently no accepted specification for surface run-off viscosity. Practice mainly relies on empirical tests and experience. As the establishment of such a specification encompasses performance of the binder in various environments or field conditions, this study was undertaken to determine performance of the selected binder. Viscosity was kept constant by spraying the emulsion at a constant temperature and also holding the pavement temperature constant. In order to study the run-off behaviour of the binder, run-off tests were conducted at various gradients, texture depths and spray rates. Surfacing seals of various texture depths were constructed in the laboratory. Using a spray bar, the emulsion was sprayed at various spray rates. The sample surfaces were tilted to various gradients. Results portrayed the effects of the three factors (spray rate, gradient and texture depth) on the amount of runoff. An increase in the magnitude of the factors resulted in a variation in the runoff (increase or decrease). One notable finding was that the runoff from the 9.5 mm seal was less than that from the 13.2 mm seal. The other significant finding was that spray rate had the largest effect on runoff, followed by texture depth, and gradient. / AFRIKAANSE OPSOMMING: Sekere eienskappe wat oppervlakdreinering van bitumen emulsies op paaie beinvloed, is bestudeer om sodoende binders wat gebruik word in die konstruksie van die seëls beter te verstaan. Afloop van die binder vanaf die padoppervlak kan lei tot die vorming van ‘n laag met ongelyke dikte wat moontlike rafeling (Johannes, Hanz & Bahia nd) en bloeing vanuit die onderkant van die pad tot gevolg kan hê. Daar is tans geen aanvaarde spesifikasies wat hierdie verskynsels inperk nie. Konstruksie praktyk berus hoofsaaklik op empiriese toetse en ondervinding. Hierdie studie is dus onderneem om prestasie van die geselekteerde binder vas te stel. Viskositeit was konstant gehou deur die aangewende emulsie en padtemperatuur konstant te hou. Ten einde die afloopgedrag van die binder te bestudeer, is toetse uitgevoer op verskeie hellings, tekstuurdieptes en aanwendingskoerse. Seëls van die verskillende tekstuurdieptes is gebou in die laboratorium, en emulsies op hierdie oppervlaktes aangewend. Die toetsoppervlakte is gekantel om die vereiste helling te kry. Resultate vir die drie faktore wys die invloed op afloop. ‘n Toename in die grootte van die faktore het gelei tot 'n variasie in die afloop (toename of afname). Een noemenswaardige bevinding was dat die afloop van die seël van 9,5 mm minder was as dié van die seël van 13,2 mm. Belangrike bevindinge sluit ook in dat die spuitkoers die grootste invloed het op afloop, gevolg deur die tekstuur diepte en die gradiënt.

Biomass waste has been recognised as a promising, renewable source for future transport fuels. With 1.7 million hectares of pine plantation forests and 12 million cubic meters of annual residue produced by sawmills and the pulp and paper industries, New Zealand presents a prime location where utilisation of these resources can take the next step towards creating a more environmentally friendly future. In this research, the process of fast pyrolysis was investigated using a laboratoryscale, nitrogen-blown fluidised bed pyrolyser at CRL Energy. This equipment can process 1–1.5 kg/h of woody biomass in a temperature range of 450–550°C. The purpose of this rig was to determine the impact of various processing parameters on bio-oil yields. Next, the pyrolysis liquids (bio-oil and tar) were processed downstream into bio-bitumen. Pyrolysis experiments were carried out on Pinus Radiata and Eucalyptus Nitens residue sawdust from sawmills and bark feedstock. The properties of the collected products, including pyrolysis liquids (bio-oil and tar), gas and solid bio-chars, were measured under different operational conditions. Further analysis was also performed to determine pH, volatile content, chemical composition and calorific values of the products. The ultimate goal for this project was to develop a feasible, advanced fast-pyrolysis system for a bio-bitumen production plant using various biomass feedstocks. Additionally, a design for a bio-bitumen production plant was developed, and techno-economic analysis was conducted on a number of plant production yield cases and bio-bitumen manufacture ratios.

Dans un contexte politique où les enjeux énergétiques et environnementaux sont de plus en plus importants, il faut favoriser les techniques économes en énergie et plus respectueuse de l'environnement. Parmi ces pratiques, l'utilisation d’enrobés à l’émulsion de bitume s'est révélée être prometteuse. La fabrication et la conception d’une chaussée comprenant une couche d’enrobé à l’émulsion sont très empiriques et reposent sur des compétences locales qui tendent à en limiter le développement. La première étape pour concevoir une chaussée consiste à connaître le comportement mécanique réversible engendrées par de lourd trafic de chaque matériau qui la compose. Lors d'une deuxième étape, ces valeurs doivent être comparées aux critères de durabilité mécanique des matériaux. Dans le cas de l'enrobé à l’émulsion, aucune loi de comportement mécanique n'a été établie pour tenir compte à la fois de son états frais et durcis. Ce travail de thèse vise donc à pallier à ce manque et à améliorer les connaissances acquises sur ce matériau. Pour cela, un modèle évolutif pour l’enrobé à l’émulsion intégrant l'évolution du matériau de son état frais à l'état durci a été développé. De plus, un nouvel essai de caractérisation a été développé et mis en place pour permettre de suivre l’évolution des performances mécaniques réversibles du matériau. Les résultats obtenus à partir des différentes campagnes d’essais ont permis de caler le modèle et de montrer la pertinence du modèle. / Given a political context in which energy and environmental stakes have become increasingly dominant, road engineering practices have favoured saving energy and protecting the environment. Among these practices, the use of cold mixes treated with bitumen emulsion has proven to be a suitable technique. Cold mix design however, as well as the design of pavements including cold mix asphalt layers, is highly empirical and based on local skills. From prior experience, the transposition of established local rules from one site to another and their application to medium or heavy traffic pavements are not simple steps and tend to limit the development of this environmentally-friendly pavement technique. The first step in designing a pavement consists of knowing the stress-strain relationship of its constitutive materials in order to determine the stresses and strains generated by heavy lorry traffic. During a second step, these values must be compared with the mechanical durability of materials by reliance on damage tests comprising large numbers of load cycles. In the case of CMA, no mechanical behaviour law has been established to take into account both the fresh and cured states. This work aims to improve the knowledge acquired on this material. For this, an evolutiv model for the cold mix asphalt with bitumen emulsion incorporating the evolution of the material from its fresh state to its cured state has been developed. In addition, a new characterization test was developed and put in place to monitor the evolution of the reversible mechanical performance of the material. The results obtained from the test campaigns helped to calibrate the model and show the relevance of the model.

This thesis explored how asphaltene and naphthenic amphiphile species influence the formation (morphology and size) and stability of heavy crude oil (bitumen) emulsions. It was experimentally shown that asphaltenes produce water-in-oil emulsions. Naphthenic amphiphiles on the other hand flip the emulsion morphology to oil-in-water. It was further demonstrated that the size and stability of these emulsions is influenced by physicochemical effects such as the pH, solvent-bitumen-water ratios, solvent aromaticity, and temperature. In view of these findings, the hydrophilic-lipophilic deviation (HLD) and net-average curvature (NAC) models were looked at as potential means for predicting the formation and stability of emulsions. Owing to the complexity of bitumen emulsions, however, the HLD and NAC models were instead tested against well-defined sodium dihexyl sulfosuccinate-toluene-water emulsions. The morphologies of these emulsions were predicted as a function of the formulation salinity whereas corresponding droplet sizes were predicted as a function of the continuous phase density and interfacial tension (γow). Emulsion stability trends were in turn predicted using a collision-coalescence-separation assumption. From this assumption, emulsion stability was expressed as a function of the emulsion droplet collision frequency and activation energy. The key parameters of the highly scrutinized activation energy term included the γow, interfacial rigidity, and critical film thickness. In applying the same modeling approach to the stability of other emulsions already published in the literature, it was found that the rigidity of adsorbed multilayer/liquid crystal films cannot yet be fully accounted for. This shortcoming was the reason for which only minimum stability times were reported for bitumen emulsions.

No description available.

The inadvertent ingestion of contaminated soil is the dominant exposure route of non-volatile and semi-volatile contaminants such as polycyclic aromatic hydrocarbons (PAHs). Quantitative mass balance soil ingestion studies have been used to determine soil ingestion rates for use in human health risk assessments (HHRA) that can be used to predict the likelihood of adverse effects in individuals exposed to hazardous contaminants such as PAHs in contaminated soil. The Cold Lake region of Alberta is one of the three major oil sands regions of Alberta, and PAH concentrations in this oil sand region may be elevated in the atmosphere and the soil, resulting in increased exposures to PAHs. The area is home to Cold Lake First Nation who practice traditional activities and lifestyles that may put them in greater contact with soil than previous soil ingestion studies suggest. The primary objective of this research was to assess the soil ingestion rate in a group of First Nations subjects inhabiting the Cold lake region, and assess the carcinogenic risk posed by exposures to PAHs in air and soil. The study employed a quantitative mass balance tracer approach to estimate soil ingestion rates, and followed 9 subjects over a 13 day period. Soil and air samples were simultaneously collected to assess PAH contamination. The mean soil ingestion rate using Al and Si elemental tracers was 52 mg d-1, with a 90th percentile of 220 mg d-1, and a median soil ingestion rate of 37 mg d-1. These values are greater than the soil ingestion rates for HHRA recommended by Health Canada. The mean increase in excess lifetime cancer risk posed by inadvertent ingestion of soil to a First Nations’ individuals following traditional activities was 0.02 cases per 100,000 people with a 95% risk level of 0.067 cases per 100,000 people. Exposure to PAHs through inhalation posed a maximum lifetime cancer risk below 0.1 cases per 100,000, people. Thus, this study found no appreciable increase in excess lifetime associated with PAH exposure of First Nations’ people in the Cold Lake region.