Optimization of Mineralogy and Microstructure of Solidified Basic Oxygen Furnace Slag Through SiO{sub 2} Addition or Atmosphere Control During Hot-Stage Slag Treatment

Journal Article · Fri Feb 15 04:00:00 EST 2019 · Metallurgical and Materials Transactions. B, Process Metallurgy and Materials Processing Science

DOI:https://doi.org/10.1007/S11663-018-1444-Z· OSTI ID:22933603

Liu, Chunwei; Huang, Shuigen; Blanpain, Bart; Guo, Muxing ^[1]

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1. KU Leuven, Department of Materials Engineering (Belgium)

Valorization of basic oxygen furnace (BOF) slag is of significant importance for mitigation of the steel production’s environmental impact. The present work aims to investigate the influence of SiO{sub 2} addition and oxygen partial pressure on the mineralogical modification of a typical industrial BOF slag. The slag basicity (mass ratio of CaO/SiO{sub 2}) was varied from 1.8 to 4.4 by mixing specific amounts of SiO{sub 2} with the master BOF slag. The original and modified slags were remelted and solidified under argon or air atmosphere followed by slow cooling. The experimental observations were then compared with the results of thermodynamic modeling to achieve a thorough understanding. With decreasing the basicity, free lime was eliminated, as it forms dicalcium silicate (Ca{sub 2}SiO{sub 4}). With increasing oxygen partial pressure, wustite was oxidized to hematite, which combined with free lime to form calcium aluminoferrite (C{sub 2}AF). The effects of SiO{sub 2} addition and oxygen partial pressure were finally evaluated with respect to the energy consumption for the BOF slag valorization. The modified slag is suitable as a precursor for construction applications as binders.

• OSTI ID: 22933603
• Journal Information: Metallurgical and Materials Transactions. B, Process Metallurgy and Materials Processing Science, Journal Name: Metallurgical and Materials Transactions. B, Process Metallurgy and Materials Processing Science Journal Issue: 1 Vol. 50; ISSN 1073-5615; ISSN MTBSEO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AIR
ARGON
CALCIUM OXIDES
CALCIUM SILICATES
CONTROLLED ATMOSPHERES
COOLING
ENERGY CONSUMPTION
ENVIRONMENTAL IMPACTS
FURNACES
HEMATITE
MASS
MICROSTRUCTURE
MINERALOGY
MITIGATION
MIXING
OPTIMIZATION
OXYGEN
PARTIAL PRESSURE
SILICON OXIDES
SLAGS
STEELS
THERMODYNAMIC MODEL