Ce travail de thèse part d’un constat : d’importantes pertes thermiques sont observées lors de l’élaboration des matériaux du génie civil. Motivés par l’ajout d’une double enveloppe, les travaux contenus dans ce manuscrit visent à caractériser un échangeur de chaleur appliqué en paroi des fours rotatifs. Tout d’abord, un modèle intégré est développé, puis validé sur une centrale d’enrobage dont la paroi intérieure du four est munie de releveurs nécessaires au mélange des matériaux. Leur distribution dans la section transversale est estimée à partir d’une loi de déchargement granulaire. Les expérimentations numériques montrent que les transferts Gaz / Solide et Solide / Paroi dominent, ce dernier phénomène limitant les performances globales du procédé. L’ajout de l’échangeur sur paroi mobile est quant à lui exploré sur un banc d’essai instrumenté de type rotor-stator, avec entrée tangentielle. Développant un écoulement de type Taylor-Couette-Poiseuille, les transferts thermiques pariétaux sont caractérisés expérimentalement. Les résultats sont sans équivoque dans la gamme de nombres de Reynolds imposés : la contribution du mouvement axial surpasse le mouvement rotationnel turbulent. Une corrélation adimensionnelle basée sur le nombre de Nusselt est proposée afin d’estimer numériquement l’effet de l’échangeur sur les profils de température internes dans le four. Enfin, les structures tourbillonnaires de l’écoulement dans l’espace annulaire sont étudiées à partir d’un code de mécanique des fluides numériques utilisant la Simulation aux Grandes Echelles. Les simulations permettent de décrire les cellules contrarotatives au sein de la couche limite turbulente dont l’amplitude et la fréquence de passages sont reliées aux paramètres de fonctionnement de l’échangeur (débit axial et vitesse de rotation du four). / This work results on a finding: the heat loss from rotary kiln represents a significant energy amount during materials processing in civil engineering domain. Motivated by traditional energy recovery methods from heat exchanger, this thesis is aimed at providing their rigorous thermodynamic diagnostics. Firstly, a thermal-granular model is developed, and then validated in asphalt plant whose the rotary kiln is composed of flights to ensure the materials mixing. Their cross-section distribution is calculated from a granular discharge law. The numerical experiments showed an increase of heat transfer phenomena between gases and solids, and those between the solids and the wall, this latter phenomenon limiting the process performances. Heat recovery exchanger applied to the rotary kiln is studied from a semi-industrial pilot based on a rotor stator configuration including a tangential inlet. Developing a Taylor-Couette-Poiseuille flow, the heat transfer results are undoubted in the range of the studied Reynolds numbers: the axial motion contribution is larger than the rotational turbulent motion. A dimension less criterion is proposed in order to be applied to the aforementioned integrated model including the heat exchanger applied to the rotary kiln, its effect being assessed upon the internal thermalprofiles. Finally, the vortices flow structure within the annular gap exchanger is studied from Large Eddy simulation. The amplitude and frequency passage of the contrarotatives cells located in the turbulent boundary layer are connected to the process parameters (the axial flowrate and the kiln shell rotation).

Cette étude, réalisée dans le cadre d’une thèse de doctorat, s’appuie à la fois sur des missions de terrain (prospections, étude du mobilier amphorique issu de ces examens de surface et de fouilles archéologiques) et sur des recherches documentaires. Nous avons débuté par l’analyse des sources écrites et iconographiques qui témoignent de la vigne et du vin. Elles nous renseignent sur l’importance de ces denrées en Cilicie depuis l’époque archaïque. Nous avons poursuivi avec les installations agricoles que nous avons répertoriées. Celles-ci traduisent la place de la viniculture en Cilicie durant l’Antiquité. Leur nombre substantiel corrobore le témoignage des sources sur l’importance du vin. Les prospections pédestres nous ont permis d’identifier plusieurs ateliers amphoriques datés de l’époque romaine. Ces découvertes attestent que des amphores, récipients privilégiés du commerce maritime, étaient produites dans cette province orientale. Une partie de la production viticole était donc exportée. Le matériel récolté sur les centres de production fut étudié en vue d’établir une chrono-typologie des six types d’emballages de transport maritime façonnés localement. Enfin, le recensement des sites de consommation où ces récipients furent exportés permet de dresser la carte de diffusion des amphores locales et donc de retracer les réseaux d’échanges dans lesquels était impliquée la Cilicie. Ces données sont indispensables en vue d’appréhender l’importance tenue par le vin de cette région littorale dans le cadre plus général du commerce maritime de l’Empire romain. / This study was carried out in the context of a Ph.D thesis. It is based both on field work (surveys, studies of amphorae collected during surveys and during archaeological excavations) and on documentary research. First, the analyse of ancient sources, written and iconographic, attest to the importance of oil and wine as surplus commodities in this Mediterranean province. Investigated press elements furnish insight to the place of Cilician viticulture during Antiquity. The substantial number of these elements reinforce the assertions of ancient sources that wine was a signficant surplus commodity of this region. During our survey we identified several Roman-era kiln-sites in the region. Their presence demonstrates that Cilician transport amphorae, or maritime shipping containers, were produced to accomodate this trade. Analysis of amphora remains collected at the kiln sites and nearby excavations enabled us to construct a chrono-typology of six amphorae that were produced locally. Last, we compared our results with those of materials published at excavations conducted throughout the Mediterranean and beyond. This enabled us to trace the distribution patterns and commercial networks of Cilician surplus commodities. These data become crucial to our understanding of the place of Cilician wine trade in the wider Roman Mediterranean economy.

The topic of the diplome thesis is draft of the waste-to-energy plant for municipal waste with cogeneration of heat. Basic specification of project: Waste-to-Energy plant is facilitated by two rotary kilns of type operating in parallel. Further flue gas leaving the post-combustor enters a multicyclone unit to separate substatial portion of fly-ash. Heat of flue gas at the temperature of 1000°C generates superheated steam in a Heat Recovery Steam Generator (HRSG). Dry sorption process is appllied for flue gas treatment. Specifically sodium bi-carbonate is used for it. Products of reactions and remnants of dust are separated by a baghouse. Superheated steam, generated by two HRSG, presents the inlet stream of a condensing steam turbine with steam extraction. The diploma thesis contains calculation of major devices and basic economical and financial statement of project.

The thesis deals with analysis of calcium carbide production process. The aim of the thesis is to identify and design savings resulting from the use of energy contained in flue gas, which is produced during the process. In the first part, history and applications of calcium carbide are presented. The thesis then contains mass and energy balance of calcium carbide production. Balance is related to 1 ton of the product. In conclusion, possibilities of flue gas use for coke drying are proposed. The thesis is based on the information from the calcium carbide factory located in Sundsvall, Sweden.

The thesis deals with the study and the characterization of bypass dusts from the cement plants. The aim of the thesis is to search for the possibilities of the usage of that secondary product by means of the cement production. The thesis focuses mainly on the determination of the amount of soluble substances in the dusts, the dependence of dissolution of the soluble share on water – dust ratio, the dependence of dissolution time on the yield of the soluble share and the influence of the temperature on the yield. The physical and chemical properties of the investigated samples taken from several cement plants in the Czech Republic and Slovakia were found out by using the following methods: by TG/DTA analysis, particles size by laser diffraction, phase composition of raw materials, treated raw materials and evaporation residues by X-ray diffraction. It was further investigated whether there was a link between finesse of the particles and the content of soluble substances (chlorides). This was accomplished by classification of the bypass dusts as fine and coarse fraction on the air cassifier with the target parameter X50 1 m. The aim of the classification was to find out whether some of the fractions carry majority share of some of components.

This thesis deals with archaeological evidence of medieval pottery products which were discovered during the emergency archaeological excavation in the area of former Jiřího z Poděbrad barracks on Náměstí Republiky square in Prague. This area is nowadays called Palladium shopping centre. The first part of the thesis deals with real findings. These are construction debris of burning kilns and historical evolution of its construction. The second part of the thesis compares results of excavation with historical datas. The last part of the thesis evaluates the extraordinarily huge file of ceramic artefacts from waste areas, especially defective pieces which complement the picture of medieval pottery production.

Im Mittelpunkt der Arbeit steht die prozess- und steuerungstechnische Untersuchung der biologischen Trocknung von Restabfällen im dynamischen Reaktor. Die gezielte Kombination von biologischen und mechanischen Prozessen innerhalb eines Reaktors führt zu Eigenschaften des Outputmaterials, die die prinzipielle Überlegenheit des dynamischen Reaktors hinsichtlich Prozessbeeinflussbarkeit und Produktqualität deutlich belegen. Die vorgestellte Steuerungslösung besteht aus einem Modul zur Klassensteuerung, der in eine übergeordnete Ablaufsteuerung eingebettet wurde. Diesem Aufbau liegt die Feststellung zu Grunde, dass beim diskontinuierlich geführten Prozess die Eigenschaften des Reaktor-Abfall-Systems von Charge zu Charge sehr unterschiedlich ausfallen können. Mit fortschreitender Prozesszeit können bestimmte Eigenschaften, im konkreten Fall Wassergehalt und Aktivität des Materials aus dem Prozessverlauf selbst bestimmt werden. Voraussetzung dazu ist die Schaffung von vergleichbaren Prozessbedingungen durch eine vorgegebene Reihenfolge von Handlungen zu Beginn des Prozesses. Ab einem bestimmten Informationsstand kann die bis dahin schematische in eine automatische Prozessführung überführt werden. In dieser werden an die aktuelle Prozesssituation angepasste Handlungen ausgeführt.

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Glass has been made and used for centuries but South African artists, isolated for the last three decades, are only now becoming aware of the potential of hot or warm glass as an art medium. In antiquity glass objects were created using various processes but the 'factory' tradition began with the discovery of the blowing iron in the first century AD. The invention of the tank furnace in the late 1950s revolutionised modem production, enabling individual artists to make glass in private studios without blowing teams. The research describes ancient.. glassmaking processes and indicates how they have been explored, adapted and used by contemporary artists world wide, challenging craft orientated paradigms, and proving that glass is a viable and important sculpture medium. The practical research demonstrates the application of many processes and relates technical issues to sculptural concepts which are realized through the physical and material properties of glass. / Art History, Visual Arts & Musicology / M.A. (Fine Art)

A finalidade deste trabalho é estudar a redução carbotérmica de minério hematítico com misturas e pelotas autorredutoras em um forno rotativo experimental. Trabalhou-se com duas temperaturas, a 1673 e 1773 K (1400 a 1500 °C), em fluxo de argônio de 1Nl/min, em um forno rotativo experimental aquecido por resistências, com uma rotação fixa de 5 rpm. Foram realizadas diversas experiências, alterando variáveis como a temperatura, composição e quantidade da escória, tipo de redutor, e tipo de conformação. Foi estudado o tempo de residência das pelotas e misturas autorredutoras dentro do forno e sua interrelação com a inclinação do mesmo. Mediu-se a resistência a compressão de diferentes composições de pelotas. Foi analisada a fração de redução atingida nas experiências com ajuda de um método indireto proposto neste trabalho, atingindo-se frações de redução acima de 98%. Especial atenção foi dada para os casos limites estudados, o primeiro com uma mistura autorredutora de 81% de minério hematítico de baixo teor, 19% de coque de petróleo,+10% cimento ARI, processada a 1773 K (1500 °C) com 33% de escória final, a qual, apesar da grande quantidade de escória, atingiu uma fração de redução de 98,7%; e o segundo, para uma mistura autorredutora de 43,5% de minério hematítico de baixo teor, 56,5% de pó de serragem, processada a 1773 K (1500 °C), a qual atingiu uma fração de redução de 99,2%, provando, com as ressalvas cabíveis, a factibilidade de reduzir diretamente com pó de serragem. Com base nas observações experimentais sugeriram-se modelos do processo de redução-fusão tanto das misturas como das pelotas autorredutoras no forno rotativo. Analisaram-se a composição da escória e a composição da fase metálica obtida. Para comparar o grau de coalescimento entre as amostras, foram levantadas as análises granulométricas de cada uma delas, comparando-se as porcentagens em massa dos nódulos de ferro-carbono com diâmetro superior a 7,93 mm. Atenção especial foi dada ao método de desagregação do produto; pela ausência de normas técnicas especificas para processos autorredutores, foi empregada uma adaptação do método de desagregação por tambor (ASTM E279-95), e validada por moagem manual. Estudou-se o efeito das variáveis: temperatura de processamento, temperatura liquidus da escória, da quantidade de escória de alta temperatura liquidus, da quantidade de voláteis do redutor, da quantidade do redutor, e da ausência de conformação. Entre os resultados destas experiências tem-se que a maior temperatura de processamento leva a maior grau de coalescimento. Na medida em que a escória do sistema não se liquefaz, o processo de coalescimento é prejudicado. Na medida em que a quantidade de escória com alta temperatura liquidus aumenta, o grau de coalescimento decresce. Ao se aumentar a quantidade do redutor acima do necessário para a correta redução, carburação e colaescimento, prejudica-se o processo de formação dos nódulos de ferro-carbono. Ao se comparar o grau de coalescimento obtido entre as misturas e as pelotas autorredutoras, temse que o desempenho das misturas autorredutoras é superior. Para aclarar o efeito da temperatura liquidus da escória no processo de carburação e coalescimento, foram realizadas experiências paralelas para estudar como a temperatura liquidus da escória e a ausência do FeO afetava o coalescimento. Ao estudar o transporte de carbono pelas escórias sem e com a presença de um óxido redutível, tem-se que o transporte do óxido de ferro na escória sem agitação é um fenômeno difusivo. / The purpose of this work is to study the carbothermal reduction of hematite ore as self-reducing mixtures or pellets in an experimental rotary kiln. Two different temperatures were employed, 1673 and 1773 K (1400-1500 ° C) in an experimental rotary kiln heated by resistors, with a fixed rotation of 5 rpm and under an argon flow of 1Nl/min. Several experiments were performed by changing variables such as temperature, composition and quantity of slag, type of carbonaceous material, and type of conformation. The residence time inside the furnace and its interrelation with the slope of the kiln containing self-reducing pellets or mixtures was studied. It was measured the compressive strength of pellets of different compositions. It has been analyzed the fractional reduction achieved in the experiments with the help of an indirect method proposed in this work, reaching fractional reduction above 98%. Special attention was given to some cases, the first one with a self-reducing mixture of 81% low grade ore, 19% petroleum coke, ARI +10%, processed to 1773 K (1500 ° C) with 33% final slag, which despite the large amount of slag reached a fractional reduction of 98.7%, and the second for a self-reducing mixture of 43.5% low-grade ore, 56.5% of sawdust processed to 1773 K (1500 ° C) which reached a fractional reduction of 99.2%, proving, with reasonable exceptions, the feasibility of reducing directly with sawdust. Based on experimental observations, process models of both the reduction-melting of self-reducing mixtures and pellets in the rotary kiln were proposed. The composition of slag and composition of the metallic phase obtained were analyzed. To compare the degree of coalescence between the samples, particle size analysis of each one was performed, comparing the percentages by weight of iron-carbon nuggets with a diameter greater than 7.93 mm. Regarding the method of disintegration of the product, due to the lack of technical standards for specific self-reducing processes, the drum method (ASTM E279-95) was adapted and validated by manual grinding. It was studied the effect of the following parameters: processing temperature, slag liquidus temperature, the amount of high liquidus temperature slag, amount of volatile matter of the reducing agent, the amount of reducing agent, and the absence of conformation. These experiments have shown that the higher the processing temperature, the greater the degree of coalescence, and also that as long as the slag does not melt, the coalescence process is impaired. As the amount of slag with high liquidus temperature increases, the degree of coalescence decreases. Increasing the amount of carbonaceous material above to that necessary to reduction and carburization undermines the process of formation of iron-carbon nuggets. When comparing the degree of coalescence obtained between the self-reducing mixtures and pellets, it has been shown that the performance of self-reducing mixtures is superior. To clarify the effect of the slag liquidus temperature in the carburization and coarsening process, experiments were conducted to study how the liquidus temperature of the slag and the absence of FeO affected the coarsening. By studying the transport of carbon in slags with and without the presence of a reducible oxide, it has been shown that the transport of iron oxide in the slag without agitation is a diffusive phenomenon.