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Thermische Effekte im Kollektorfeld solarthermischer AnlagenDimitrova, Krassimira 15 March 2006 (has links)
Angesichts der angestrebten Reduzierung der Umweltbelastung und dem Anstieg des zukünftigen Energiebedarfs nimmt die Bedeutung der regenerativen Energiequellen heutzutage zu. Ein Beispiel für Energieversorgung durch regenerative Energiequellen ist die Verwendung von thermischen Solaranlagen zur Brauchwassererwärmung. Für einen langjährigen und zuverlässigen Betrieb von Solaranlagen sind die physikalischen, thermischen sowie korrosionstechnischen Eigenschaften des Wärmeträgers von großer Bedeutung.
Ziel der Arbeit ist, die Auswirkungen thermischer Effekte auf die Eigenschaften von solar-thermischen Anlagen zu untersuchen und Erkenntnisse über deren Auswirkung auf die Prozessabläufe in Kollektoren zu erlangen. Es wird der Einfluss der temperaturabhängigen Viskosität des Wärmeträgers auf die Geschwindigkeits- und Temperaturprofile für die Rohrströmung im Kollektor dargestellt. Weiterhin werden die thermischen Belastungen für Wärmeträger während der Stagnation in Solaranlagen experimentell untersucht.
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Aufbau eines Hochtemperaturviskosimeters und Messung der Viskosität von Schmelzen des Systems Aluminium-NickelKehr, Mirko 29 October 2009 (has links)
Das System Aluminium-Nickel besitzt als Modellsystem
in der Wissenschaft sowie als ein Basissystem von
sogenannten Superlegierungen in der Technik eine
große Bedeutung. Aufgrund der hohen Liquidustemperaturen
von bis zu 1638°C sind die thermophysikalischen
Eigenschaften der Schmelzen bisher nur in den
Randbereichen des Systems bekannt. Die Viskosität
ist eine der thermophysikalischen Größen und sowohl
von der Zusammensetzung als auch von der Temperatur
abhängig. Sie besitzt eine große Bedeutung als
Eingabeparameter für Simulationsrechnungen zur
Erstarrung von Schmelzen sowie bei der Optimierung
von Herstellungsprozessen metallischer Werkstoffe.
Die Viskosität der Schmelzen im System Aluminium-Nickel
wurde nach Kenntnis des Autors bisher nur einmal
gemessen. Durch den vorliegenden Datensatz war jedoch
nicht der gesamte Konzentrationsbereich im System Aluminium-Nickel
abgedeckt. Besonders im Bereich der technologisch
interessanten hochschmelzenden Legierungen bestanden
Lücken. Mit bisherigen Viskosimetern war die Messung
der Viskositäten im gesamten System nicht möglich, da
die Liquidustemperaturen des Systems Aluminium-Nickel
die maximalen Arbeitstemperaturen überstiegen.
Im Rahmen der Arbeit wurde ein neues Schwingtiegelviskosimeter
mit hängendem Tiegel konzipiert, aufgebaut und mit
Viskositätsmessungen an reinen Metallen mit bekannter
Viskosität bei Temperaturen bis 1800°C erfolgreich
getestet. Mit weiteren Modifikationen sind mit dem
neu aufgebauten Viskosimeter Temperaturen bis 2300°C
erreichbar. Für den Betrieb des Viskosimeters wurde
ein umfangreiches Mess- und Steuerprogramm entwickelt
sowie erfolgreich getestet. Zur Berechnung der
Viskosität wurden im Messprogramm verschiedene
Arbeitsgleichungen implementiert. Für die Detektion
der Schwingung des Torsionspendels wurde ebenfalls
eine neue Methode angewendet, die eine quasikontinuierliche
und damit genauere Messung Erfassung der Schwingung
erlaubt.
Die Viskosität der Schmelzen des Systems Aluminium-Nickel
konnte erfolgreich bestimmt werden, womit experimentelles
Neuland betreten wurde. Die gemessenen Verläufe zeigen eine
gute Übereinstimmung mit den wenigen bekannten Daten
zur Viskosität von Aluminium-Nickel Schmelzen. Ebenso
gut ist die Übereinstimmung mit wenigen weiteren vorhandenen
Messdaten der Diffusionskonstanten sowie mit Daten aus
Computersimulationen. Mit verschiedenen Modellen zur
Vorhersage der Viskosität von Legierungen wurden
Viskositätsverläufe im System Aluminium-Nickel berechnet.
Der Vergleich mit den Messdaten hat gezeigt, dass nur wenige
der Modelle zur Vorhersage der Viskosität im System
Aluminium-Nickel geeignet sind. / The system aluminium-nickel is of importance as a
model-system in materials science as well as a
basic system for superalloys in technical applications.
The knowledge of the thermophysical properties of
the system aluminium-nickel has been limited to the
areas close to the pure elements mainly related to
the high melting temperatures of up to 1638°C. The viscosity, which is one of these
thermophysical properties, depends on alloy composition as
well as on temperature. The viscosity is of importance as
an input parameter in computer simulations and for
improving casting processes of metallic alloys.
The viscosity of aluminium-nickel melts has been
measured only once so far. However, not the whole
concentration range of the aluminium-nickel system
was covered by these data. In particular the viscosity
values of the high melting alloys, which are of
technological interest, were unknown. The measurement
of the missing values was not possible due to the
high melting temperatures using existing viscometers.
A new oscillating cup viscometer has been constructed
within this work. The viscometer has been tested
measuring the viscosity values of pure metals, which
are well known in literature. The test measurements
have been done at temperatures up to 1800°C. A
temperature of 2300°C is achievable with slight
modifications. A new software for controlling the
device and evaluation of the measured data has been
developed. Several working equations for calculating
the viscosity have been implemented. Furthermore a
new approach has been used for detecting the damping
of the oscillation of the pendulum containing the
liquid sample.
The viscosity of aluminium-nickel melts have been
measured successfully. The measured values are in
good agreement with the little number of known
values. A good agreement with values calculated
from diffusion experiments and computer simulations
was observed as well. Several models for calculating
the viscosity of liquid alloys have been tested and
compared with the experimental values measured in
this work. Not all the tested models can predict
the viscosity values of aluminium-nickel melts
plausibly.
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On the effect of secondary phases on gasifier slag behaviorSchwitalla, Daniel 09 March 2022 (has links)
By analyzing process samples full and pilot scale gasifiers, the main influences affecting their slag are identified. Based on this knowledge as well as the current literature, the effect of crystallization was identified as crucial for understanding slag behavior and is analyzed during cooldown. Finally, the emerging interest in sewage sludge upcycling via gasification necessitated an investigation on the influence of adding P2O5 as slag constituent. All conclusions concerning the full scale gasifier slags were based on XRF, XRD, and SEM-EDX analyses coupled with thermodynamic equilibrium calculations via FactSage. The subsequently presented research on crystallization and the effect of P2O5 was centered on conducting slag viscosity measurements, recreating the conditions of said measurement in a quench oven, and analyzing the resulting quench samples via the mentioned analysis methods. Special focus was put on the phase evolution, its governing factors, and the effect on slag viscosity.:1. INTRODUCTION 1
2. FUNDAMENTALS IN SLAG BEHAVIOR CHARACTERIZATION 3
2.1. BASE TO ACID RATIO AS KEY FIGURE FOR SLAG CHARACTERIZATION 7
2.2. VISCOSITY ALTERING SECONDARY PHASES IN SLAGS 9
2.2.1. The effect of crystallization on slag flow 10
2.2.2. Modelling and measuring crystallization in slags 11
2.3. CRITICAL VISCOSITY 13
2.4. PHOSPHOROUS OXIDE IN SLAGS 15
2.4.1. Behavior of P2O5 within slags 16
2.4.2. Phase separation in melts containing P2O5 17
2.4.3. Effect on slag viscosity 22
3. ANALYTICAL METHODS 26
3.1. SAMPLE PRETREATMENT 26
3.2. ASH FUSION TEMPERATURE 28
3.3. X-RAY FLUORESCENCE MEASUREMENT (XRF) 30
3.4. X-RAY DIFFRACTION 31
3.5. VISCOSITY MEASUREMENT 32
3.6. DIFFERENTIAL THERMAL ANALYSIS (DTA) 36
3.7. QUENCH APPARATUS 37
3.8. SEM-EDX 39
3.9. THERMODYNAMIC EQUILIBRIUM CALCULATIONS 40
4. CHARACTERIZATION OF SLAGS FROM FULL OR PILOT SCALE GASIFIERS 42
4.1. SLAG FROM GENERAL ELECTRICS GASIFIER IN TAMPA 43
4.1.1. Analysis of the suspending main phase 45
4.1.2. Analysis of the silica phase 50
4.1.3. Analysis of the metal enclosures 51
4.1.4. Analysis of the vanadium-rich particles 53
4.1.5. Summary of the analysis of the General Electrics gasifier slag 55
4.2. SLAG FROM GSP GASIFIER 57
4.2.1. NCPP slag 57
4.2.2. Huainan Anhui slag 64
4.2.3. Genesee slag 70
4.2.4. Hambach-Garzweiler 50:50 slag 75
4.2.5. Summary of the analysis of the GSP slags 86
4.3. SLAG FROM BRITISH GAS/LURGI (BGL) GASIFIER 88
4.3.1. Summary and conclusions of the analysis of the BGL slag 99
5. CHARACTERIZING CRYSTALLIZATION DURING SLAG VISCOSITY MEASUREMENTS 102
5.1. EXPERIMENTAL PROCEDURE 103
5.1.1. Sample preparation 107
5.1.2. Viscosity measurement 108
5.1.3. Differential thermal analysis (DTA) 108
5.1.4. Quench oven 108
5.1.5. XRD, XRF, SEM-EDX, and FactSage calculations 109
5.2. RESULTS AND DISCUSSION 109
5.2.1. Slag 1 (CO/CO2 atmosphere) 110
5.2.2. Slag 2 (CO/CO2 atmosphere) 112
5.2.3. Slag 3 (air atmosphere) 116
5.2.4. Slag 3 (CO/CO2 atmosphere) 119
5.3. CONCLUSION AND SUMMARY OF THE STUDY OF CRYSTALLIZATION IN SLAGS DURING COOLDOWN 122
6. THE EFFECT OF PHOSPHOROUS OXIDE ON SLAGS 125
6.1. PRELIMINARY SEWAGE SLUDGE SLAG INVESTIGATION 126
6.1.1. Conclusion and summary sewage slag investigation 136
6.2. EXPERIMENTAL PROCEDURE FOR PARAMETRIC STUDY 139
6.3. PARAMETRIC STUDY 141
6.3.1. HKN with 15% sand (HKNS) 142
6.3.2. HKNS with low P2O5 addition (HKNS5P) 147
6.3.3. HKNS with medium low P2O5 addition (HKNS10P) 153
6.3.4. HKNS with medium high P2O5 addition (HKNS15P) 158
6.3.5. HKNS with high P2O5 addition (HKNS20P) 163
6.3.6. P2O5 distribution 169
6.3.7. Effect of P2O5 on viscosity 174
6.4. SUMMARY ON THE INVESTIGATION OF P2O5 IN SLAGS 179
7. CONCLUSION AND OUTLOOK 185
8. REFERENCES 190
9. APPENDIX A: DIFFERENCE IN PREDICTION OF SEWAGE SLUDGE ELEMENTAL DISTRIBUTION 213
10. APPENDIX B COMPARISON OF XRF ANALYSES OF HKNS-P2O5 MIXTURES 215
11. APPENDIX C EDX MAPS OF THE QUENCH SAMPLES IN THE PARAMETRIC PHOSPHORUS ADDITION STUDY 218
12. APPENDIX D SUMMARY OF PHASE COMPOSITION OF THE EDX MAPS 239
13. APPENDIX E ENRICHMENT FACTORS FOR THE QUENCH SAMPLES IN THE PARAMETRIC PHOSPHORUS ADDITION STUDY 242
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Modification of Liquid Steel Viscosity and Surface Tension for Inert Gas Atomization of Metal PowderKorobeinikov, Iurii, Perminov, Anton, Dubberstein, Tobias, Volkova, Olena 08 July 2024 (has links)
Inert gas atomization is one of the main sources for production of metal powder forpowder metallurgy and additive manufacturing. The obtained final powder size distribution iscontrolled by various technological parameters: gas flow rate and pressure, liquid metal flowrate, gas type, temperature of spraying, configuration of nozzles, etc. This work explores anotherdimension of the atomization process control: modifications of the liquid metal properties andtheir effect on the obtained powder size. Series of double-alloyed Cr-Mn-Ni steels with sulfur andphosphorus were atomized with argon at 1600◦C. The results indicate that surface tension andviscosity modifications lead to yielding finer powder fractions. The obtained correlation is comparedwith the individual modification of surface tension with S and Se and modification of viscosity withphosphorus. Discrepancy of the results is discussed. Additives of surfactants and viscosity modifierscan be a useful measure for powder fractions control.
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Intra-arterial and intravenous applications of Iosimenol 340 injection, a new non-ionic, dimeric, iso-osmolar radiographic contrast medium: phase 2 experienceMeurer, Karoline, Laniado, Michael, Hosten, Norbert, Kelsch, Bettina, Hogstrom, Barry 18 September 2019 (has links)
Background: Iosimenol 340 injection is a new, dimeric, iso-osmolar, iodinated contrast medium for X-ray angiography. Purpose: To compare the safety and efficacy of iosimenol injection to iodixanol injection in two randomized, controlled phase 2 trials. Material and Methods: One hundred and forty-four adult patients were enrolled in the two trials, one for evaluation during arteriography and the other for evaluation during computed tomography. Safety was compared by assessing adverse events, vital signs, ECGs, and laboratory parameters. Efficacy was assessed as X-ray attenuation in the computed tomography (CT) trial and as the quality of contrast enhancement in the arteriography trial. Results: There were no statistically significant differences in terms of safety or efficacy between the two contrast media. Both were well tolerated upon intravenous as well as intra-arterial injection. The most common adverse event was a feeling of warmth (observed in 35.1% of the patients with Iosimenol injection and 44.3% with iodixanol injection). Conclusion: Iosimenol upon intravenous as well as upon intra-arterial injection exhibits a safety profile and shows an efficacy similar to that of iodixanol.
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Untersuchung der Fluoreszenzlebensdauer von BODIPY-Farbstoffen in Polymerlösungen und PolymerschmelzenFröbe, Melanie 09 December 2016 (has links) (PDF)
Die vorliegende Arbeit befasst sich mit dem Fluoreszenzverhalten, speziell der Fluoreszenzlebensdauer, von BODIPY-Farbstoffen in Polymerlösungsmittelgemischen mit unterschiedlicher Polymerkonzentration sowie in Polymerfilmen bei unterschiedlichen Temperaturen. Dazu werden zunächst die Synthesen von vier verschiedenen BODIPY-Fluorophoren mit einem Phenylsubstituent in meso-Position aufgezeigt. Dahingehend wurde eine Synthesestrategie entwickelt, um eine einzelne Polypropylenkette an diese Farbstoffsysteme anzubinden. Dabei soll aufgezeigt werden, dass die Länge des Substituenten am Phenylsubstituenten am chromophoren Kern maßgeblich das Fluoreszenzverhalten der Sonde beeinflusst. BODIPY-Farbstoffe mit makromolekularen Substituenten zeigen im Vergleich zu Derivaten mit kürzeren Substituenten eine deutlich größere Fluoreszenzlebensdauer und eine nicht so stark ausgeprägte Temperaturabhängigkeit. Mehrere Zeitkomponenten der Fluoreszenzlebensdauer der Fluorophore in reinem Polypropylen bzw. deren Mehrkomponentensystemen (Polyethylenpropylen Copolymer oder Kraton) im Vergleich zu reinen Lösungsmitteln (Toluol oder Dodecen) deuten dabei auf lokale Heterogenitäten im Material hin. Außerdem wird der Einfluss der Viskosität auf die Fluoreszenzlebensdauer in Polymer/Lösungsmittelgemischen mit unterschiedlicher Polymerkonzentration untersucht und die Rolle des Wasserstoffbrückennetzwerkes zwischen den Polymer- und Lösungsmittelmolekülen diskutiert.
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Viskosität metallischer Schmelzen und deren präzise MessungDong, Changxing 24 September 2001 (has links) (PDF)
Diese Arbeit berichtet über die Planung und den Aufbau eines neuen Viskosimeters und über Viskositätsuntersuchungen einiger metallischer Systeme. Diese
letzteren Messungen wurden mit einem vorhandenen Viskosimeter gemacht, in dem
kein besseres Vakuum als 10^(-3)mbar und keine höhere Temperatur als 1430K
erreicht werden kann. Das beste Vakuum und die maximale erreichbare Temperatur
in dem neuen Viskosimeter sind 10^(-6)mbar bzw. 1870K. Diese beiden Grundbedingungen ermöglichen die Viskositätsmessung metallischer Systeme, die aktive
Elemente wie Al, Mg und P enthalten oder/und einen höheren Schmelzpunkt
besitzen. Mit dem Drei-Zonen-Ofen erlaubt die neue Apparatur auch ein schnelleres
Homogenisieren der zu untersuchenden Schmelze, besonders der monotektischen
Systeme. Der Einfluß der Temperatur des Torsionsdrahtes und der Anfangsphase
der Schwingung auf die Genauigkeit der Viskostätsmessung wurden analysiert und
entsprechende Verbesserungen vorgeschlagen. Die untersuchten Systeme sind das
Zn-Pb basierte ternäre System, die monotektischen Systeme Ag-Te und Li-Na,
das Verbindungssystem Sb-Zn, die halbleitenden Cd-Te Legierungen und Schaummaterialien ZACT und ZACM. / Viscosity of metallic melts and its precise measurement
This thesis reports the design and the construction of a new oscillating cup
viscometer and the viscosity investigation of several metallic systems. The
measurements were carried out with an existing viscometer by which one could
not get better vacuum than 10^(-3)mbar or higher temperature than 1430K.
With the new apparatus the best vacuum of 10^(-6)mbar and the highest temperature of 1870K can be reached. These two basic conditions permit the measurement
of systems which contain active elements such as Al, Mg and P and/or have very
hight melting points. The construction of the three-zone furnace in the new
viscometer allows the acceleration of the homogenising process, which is
especially important for monotectic systems. The influences of the temperature
of the torsion thread and the initial oscillating phase on the accuracy of
viscosity measurement were analysed and the corresponding solutions were put
forward. The investigated systems are the Zn-Pb based ternary system, the
monotectic systems Ag-Te and Li-Na, the Sb-Zn system which contains compounds
in the solid phases, the semiconducting Cd-Te alloys and the foaming materials
ZACT and ZACM.
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Influence of the Melt Flow Rate on the Mechanical Properties of Polyoxymethylene (POM) / Einfluss des Schmelzfließindex auf die mechanischen Eigenschaften von Polyoxymethylen (POM)Faust, Karsten, Bergmann, André, Sumpf, Jens 19 December 2017 (has links) (PDF)
In this article the correlation between the average molar mass and the melt flow rate (MFR) is achieved. Based on the example of Polyoxymethylene (POM) it is shown that a high average molar mass is associated with a low MFR (high viscosity). On the basis of this dependency, the mechanical properties of static and dynamic tensile strength, elastic modulus, hardness and notched impact strength are investigated. It was found that the characteristic values of static tensile strength, elastic modulus and hard-ness increase with increasing MFR (decreasing viscosity). On the other hand the dynamic long-term properties and notched impact strengths decrease with increasing MFR. / Im Beitrag wird der Zusammenhang zwischen der mittleren molaren Masse und des Schmelzfließindex (MFR) hergestellt. Dabei wird am Beispiel von Polyoxymethylen (POM) ersichtlich, dass eine hohe mittlere molare Masse mit einem geringen MFR (hochviskos) einhergeht. Basierend auf dieser Abhängigkeit werden die mechanischen Eigenschaften statische und dynamische Zugfestigkeit, E-Modul, Härte sowie Kerbschlagzähigkeit untersucht. Dabei konnte festgestellt werden, dass die Kenngrößen statische Zugfestigkeit, E-Modul und Härte mit steigendem MFR (abnehmende Viskosität) zunehmen. Die dynamischen Langzeiteigenschaften und Kerbschlagzähigkeiten sinken hingegen mit zunehmendem MFR.
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Viscosity of slags / Viskosität von SchlackenBronsch, Arne 06 October 2017 (has links) (PDF)
Slags plays a significant role at high temperature processes. The estimation of the slag viscosity is vital for the safe run of e.g. entrained flow gasifiers. One opportunity of determination is rotational viscometry. This technique is disadvantageous in view of elevated temperatures, applied materials and the necessary time. Additionally, the viscosity can be predicted by the help of viscosity models, where viscosity is a function of slag composition and temperature. Due to changing slag properties within the technical processes, the calculated viscosities can hugely differ from measured ones.
In this work, the viscosities of 42 slags where measured up to 100 Pa s and temperatures up to 1700 °C. Oxidizing and reducing conditions were applied. Additionally, selected slag samples were quenched at defined temperatures to qualitatively and quantitatively determine the formed minerals by X-ray diffraction (XRD). Differential temperature analysis (DTA) was applied to find the onset of crystallization for the complementation of investigations.
The Einstein-Roscoe equation was chosen to improve the classic viscosity models. Reducing atmosphere decreased viscosity and the number of formed minerals was increased. Slags show a shear-thinning behavior above ca. 10 vol.-% of solid mineral matter. Also, Newtonian behavior was observed up to 60 vol.-%. To overcome problems with the kinetic cooling behavior of the slags, a viscosity approximation method was applied afterwards. This can result in optimized viscosity predictions when several preconditions are fulfilled.
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Viscosity of slagsBronsch, Arne 13 July 2017 (has links)
Slags plays a significant role at high temperature processes. The estimation of the slag viscosity is vital for the safe run of e.g. entrained flow gasifiers. One opportunity of determination is rotational viscometry. This technique is disadvantageous in view of elevated temperatures, applied materials and the necessary time. Additionally, the viscosity can be predicted by the help of viscosity models, where viscosity is a function of slag composition and temperature. Due to changing slag properties within the technical processes, the calculated viscosities can hugely differ from measured ones.
In this work, the viscosities of 42 slags where measured up to 100 Pa s and temperatures up to 1700 °C. Oxidizing and reducing conditions were applied. Additionally, selected slag samples were quenched at defined temperatures to qualitatively and quantitatively determine the formed minerals by X-ray diffraction (XRD). Differential temperature analysis (DTA) was applied to find the onset of crystallization for the complementation of investigations.
The Einstein-Roscoe equation was chosen to improve the classic viscosity models. Reducing atmosphere decreased viscosity and the number of formed minerals was increased. Slags show a shear-thinning behavior above ca. 10 vol.-% of solid mineral matter. Also, Newtonian behavior was observed up to 60 vol.-%. To overcome problems with the kinetic cooling behavior of the slags, a viscosity approximation method was applied afterwards. This can result in optimized viscosity predictions when several preconditions are fulfilled.:List of Tables ............................................................................................................ vi
List of Figures ........................................................................................................ viii
Symbols and Abbreviations .................................................................................. xviii
1. Introduction and Aim ....................................................................................... 1
2. General Overview of Slag ............................................................................... 2
2.1 Viscosity ...................................................................................................... 2
2.1.1 Viscosity Introduction ........................................................................... 2
2.1.2 Flow behavior of fluids ......................................................................... 3
2.2 Slag Definition and Phase Diagrams ........................................................... 4
2.3 Solid Slag Structure .................................................................................... 5
2.4 Liquid Slag Structure ................................................................................. 10
2.5 Basicity and B/A-ratio ................................................................................ 11
2.6 Slag Components...................................................................................... 13
2.6.1 Silicon dioxide .................................................................................... 13
2.6.2 Aluminum oxide ................................................................................. 13
2.6.3 Calcium oxide .................................................................................... 15
2.6.4 Iron oxide ........................................................................................... 16
2.6.5 Magnesium Oxide .............................................................................. 18
2.6.6 Potassium Oxide ................................................................................ 19
2.6.7 Sodium Oxide .................................................................................... 20
2.6.8 Titanium Oxide ................................................................................... 21
2.6.9 Phosphorous ...................................................................................... 22
2.6.10 Sulfur .............................................................................................. 22
2.7 Summary of Last Chapters ........................................................................ 23
3. Slag Viscosity Toolbox .................................................................................. 25
3.1 Slag Viscosity Predictor............................................................................. 25
3.2 Slag Viscosity Database............................................................................ 26
3.3 Prediction Quality of Viscosity Models ....................................................... 27
4. Classic Slag Viscosity Modelling ................................................................... 30
4.1 Selected Classic Viscosity Models ............................................................ 31
4.1.1 S2 ....................................................................................................... 32
4.1.2 Watt-Fereday ..................................................................................... 32
4.1.3 Bomkamp ........................................................................................... 32
4.1.4 Shaw .................................................................................................. 32
4.1.5 Lakatos .............................................................................................. 33
4.1.6 Urbain ................................................................................................ 33
4.1.7 Riboud ............................................................................................... 33
4.1.8 Streeter .............................................................................................. 34
4.1.9 Kalmanovitch-Frank ........................................................................... 34
4.1.10 BBHLW .......................................................................................... 34
4.1.11 Duchesne ....................................................................................... 34
4.1.12 ANNliq ............................................................................................ 35
4.2 Need of Improvement in Viscosity Literature ............................................. 35
4.3 Summary of Last Chapters ........................................................................ 36
5. Advanced Slag Viscosity Modelling .............................................................. 37
5.1 Crystallization ............................................................................................ 37
5.1.1 Nucleation .......................................................................................... 38
5.1.2 Crystallization Rate ............................................................................ 39
5.1.3 Crystallization Measurement Methods ............................................... 39
5.2 Slag Properties Changes During Crystallization ........................................ 40
5.2.1 Slag Density ....................................................................................... 40
5.2.2 Solid Volume Fraction ........................................................................ 46
5.2.3 Estimation of Slag Composition During Cooling ................................. 46
5.3 Viscosity Depending on Particles and Shear Rate..................................... 47
5.3.1 Einstein-Roscoe Equation .................................................................. 48
5.3.2 Improved Modelling Approach by Modified Einstein-Roscoe .............. 49
5.4 Summary of Last Chapters ........................................................................ 50
6. Experimental Procedures ............................................................................. 52
6.1 Viscosity Measurements ........................................................................... 52
6.1.1 Estimating Parameter Ranges of Viscosity Measurements ................ 53
6.1.2 Viscosity Measurement Procedure ..................................................... 54
6.2 Thermal Analysis of Slags ......................................................................... 55
6.2.1 Experimental Conditions of DTA ........................................................ 55
6.3 Phase Determination ................................................................................. 55
6.3.1 Quench Experiment Processing ......................................................... 56
6.3.2 Phase Determination on XRD Results ............................................... 56
6.4 Summary of Last Chapters ........................................................................ 57
7. Results and Discussion ................................................................................ 58
7.1 Selected Slag Samples ............................................................................. 58
7.1.1 Slag Sample Composition Before Viscosity Measurements ............... 58
7.1.2 Slag Sample Composition After Viscosity Measurements .................. 59
7.2 General Results of Viscosity Measurements ............................................. 60
7.2.1 Viscosity under Air Atmosphere ......................................................... 63
7.2.2 Viscosity under Reducing Atmospheres ............................................. 65
7.2.3 Viscosity under Constant Partial Oxygen Pressure ............................ 66
7.2.4 Summary of Last Chapter .................................................................. 68
7.3 Mineral Formation ..................................................................................... 69
7.3.1 General Results on Primarily Mineral Formation ................................ 69
7.3.2 Influences on Primarily Mineral Formation ......................................... 70
7.3.3 Mineral Formation over Wide Temperature Ranges ........................... 71
7.3.4 Summary of Last Chapter .................................................................. 77
7.4 Results Obtained by DTA .......................................................................... 78
7.4.1 Comparing Results obtained by DTA and Quenching ........................ 80
7.4.2 Summary of Last Chapter .................................................................. 82
7.5 Shear Rate Influence on Slag Viscosity ..................................................... 82
7.5.1 Shear Rate Influence under Oxidizing Atmospheres .......................... 83
7.5.2 Shear Rate Influence under Reducing Atmospheres .......................... 87
7.5.3 Shear Rate Influence under Constant Atmospheres .......................... 91
7.5.4 Summary of chapter ........................................................................... 92
7.6 Atmospheric Influence on Viscosity ........................................................... 93
7.6.1 Summary of Last Chapter .................................................................. 95
7.7 Cooling Rate Influence on Slag Viscosity .................................................. 95
7.7.1 Summary of Last Chapter .................................................................. 97
8. Advanced Viscosity Modelling Approach ...................................................... 99
8.1 Prediction Quality of Classical Viscosity Models ........................................ 99
8.1.1 Selecting the Best Viscosity Model for Newtonian Flow ..................... 99
8.1.2 Summary of Last Chapter ................................................................ 103
8.2 Predicting Liquidus Temperature ............................................................. 103
8.2.1 Comparing Liquidus Calculations and Quenching Experiments ....... 103
8.2.2 Comparing DTA Results and Liquidus Calculations ......................... 105
8.2.3 Summary of Last Chapter ................................................................ 107
8.3 Predicting Liquid Slag Composition ......................................................... 108
8.3.1 Results of Slag Composition Calculations at Oxidizing Conditions ... 108
8.3.2 Results of Slag Composition Calculations at Reducing Conditions ... 110
8.3.3 Summary of Last Chapter ................................................................ 111
8.4 Modelling Approach ................................................................................ 112
8.4.1 Development of Datasets for Advanced Viscosity Modeling ............. 113
8.4.2 Summary of Last Chapter ................................................................ 116
8.5 Results of Advanced Slag Viscosity Modelling Approach ........................ 116
8.5.1 Summary of Last Chapter ................................................................ 121
9. Summary .................................................................................................... 123
10. Appendix: Information on Classic Viscosity Modelling ................................. 126
10.1 Backgrounds of Applied Viscosity Models............................................ 126
10.2 Viscosity Model of the BCURA (S2) ..................................................... 129
10.3 Watt-Fereday ....................................................................................... 130
10.4 Bomkamp ............................................................................................ 130
10.5 Shaw ................................................................................................... 131
10.6 Lakatos Model ..................................................................................... 132
10.7 Urbain Model ....................................................................................... 133
10.8 Riboud Model ...................................................................................... 134
10.9 Streeter Model ..................................................................................... 136
10.10 Kalmanovitch-Frank Model .................................................................. 137
10.11 BBHLW Model ..................................................................................... 137
10.12 Duchesne Model .................................................................................. 139
10.13 ANNliq Model ...................................................................................... 141
11. Appendix: Settings of Equilibrium Calculations ........................................... 143
12. Appendix: Parameters of Einstein-Roscoe Equation ................................... 153
13. Appendix: Ash and Slag Sample Preparation ............................................. 155
14. Appendix: Experimental Procedures: Viscometer ....................................... 159
14.1 General Viscometer Description .......................................................... 159
14.2 Temperature Calibration ...................................................................... 160
14.3 Viscometer Calibration ......................................................................... 160
14.4 Accuracy and Reproducibility of HT-Viscosity Measurements .............. 161
14.5 Influence of Inductive Heating .............................................................. 163
14.6 Influence of Measurement System Materials ....................................... 164
15. Appendix: Experimental Procedures: Quenching Furnace .......................... 167
16. Appendix: Slag Sample Parameters and Composition ................................ 168
17. Appendix: Slag Viscosity Measurements Results ....................................... 175
18. Appendix: Viscosities at Different Cooling Rates ........................................ 182
19. Appendix: Slag Viscosity Modelling: AALE Calculations ............................. 187
20. Appendix: Advanced Viscosity Modelling: a-factors .................................... 193
21. Appendix: Slag Mineral Phase Investigations and Modelling ...................... 197
22. Appendix: Results of DTA Measurements on Slags .................................... 207
23. Appendix: Advanced Slag Viscosity Modelling Approach ............................ 211
References ........................................................................................................... 228
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