학술논문

Viscosity of SiO2–CaO–Al2O3 slag with low silica – Influence of CaO/Al2O3, SiO2/Al2O3 ratio
Document Type
Source
ISIJ International. 58(12):2180-2185
Subject
Driving force
Low silica slag
Slag
Suspension
Viscosity
Alumina
Aluminosilicates
Aluminum oxide
Slags
Suspensions (fluids)
Temperature distribution
Abnormal behaviours
Aerodynamic levitation
Cluster formations
Composition ranges
Degree of polymerization
Driving forces
Temperature dependence
Wide temperature ranges
Silica
Language
English
ISSN
0915-1559
Abstract
The viscosity of low SiO2 (10–20 mass%)-CaO-Al2O3 slag system was measured in a wide temperature range (1 623–2 800 K) using the rotational bob method and the aerodynamic levitation method. The influence of SiO2/Al2O3 ratio and CaO/Al2O3 ratio on the viscosity was examined. It was concluded that the SiO2/Al2O3 ratio did not affect the degree of polymerization of the aluminosilicate network in the composition range of the present study. An abnormal behaviour of the viscosity was observed at a CaO/Al2O3 ratio of 1.57 which was attributed to the formation of 12CaO·7Al2O3-like clusters. It was concluded that the overall influence on the viscosity could be expressed as the summation of the influence from the aluminosilicate network and the influence from the cluster formation of the primary precipitating solid phase. The temperature dependence of the cluster formation was coupled to the driving force of precipitation of the 12CaO·7Al2O3 phase.