TY  - THES
AU  - Nentwig, Thomas
TI  - Experimentelle Bestimmung und numerische Simulation von Viskositäten in Schlackesystemen unter Vergasungsbedingungen
VL  - 129
PB  - RWTH Aachen
VL  - Dr. (Univ.)
CY  - Jülich
M1  - PreJuSER-18561
SN  - 978-3-89336-756-6
T2  - Schriften des Forschungszentrums Jülich : Energie & Umwelt / Energy & Environment
SP  - XIII, 156, XV-LXXVI Seiten
PY  - 2011
N1  - Record converted from JUWEL: 18.07.2013
N1  - RWTH Aachen, Diss., 2011
AB  - Silica melts are reflected in many different industrial and natural processes such as slags in steel production and gasification of coal, glass in the glass making industry, lava in the volcanology and in lots of other fields. Rheological properties like the viscosity of this silica melts are really important in all of these processes. A general and good working viscosity model would help all scientists and engineers, who have to simulate and optimise these processes. First, it is important to have the possibility to measure viscosities of slags. As part of this PhD thesis a new high-temperature high-pressure rotational viscosimeter is developed for measurements up to ≥1600 °C and 20 bar. Particularly in relation to the coal gasification process this two parameters are really important, because coal gasification occurs under high temperatures and high pressures. With this new viscosimeter it is possible to measure slag viscosities under realistic gasification conditions. To show that the new viscosimeter works quite good viscosity measurements of four real slags have been done. The influence of pressure and atmosphere on viscosity have been examined. The measurements are also compared with different viscosity models. The Arrhenius- and Weymann-Equation have been determined and the correlation between viscosity and basicity of the slag has been evaluated. In the second part of the Phd thesis a new viscosity model is developed. The model is based on the structure inside the slag and consists in existing thermodynamic models. After a detailed literature research the model is developed for the SiO$_{2}$-Al$_{2}$O$_{3}$-Na$_{2}$O-K$_{2}$O system. The quality of this new model is estimated by comparing calculated viscosity values with measurements found during the literature research. The new model is also compared with other existing models for viscosity calculation.
LB  - PUB:(DE-HGF)11 ; PUB:(DE-HGF)3
UR  - https://juser.fz-juelich.de/record/18561
ER  -