Slag Formation – Thermodynamic Aspects and Experimental Observations
-
Lauri Holappa
and
Yilmaz Kacar
Abstract
Slags have a central role in pyro-metallurgical processes. They bind impurity compounds and absorb reaction products like oxides and sulfides. Functional slags are made by adding lime, magnesia, fluorspar, bauxite, calcium aluminate or other compounds into the reactor vessel where they form the slag together with the targeted reaction products. Additionally, refractory materials of the vessel tend to dissolve into the slag and thus influence its properties. Converter process for steelmaking is a rapid process and slag formation is extremely essential to ensure slag’s metallurgical functions and to avoid harmful reactions with the refractory materials. In this contribution, the progress of understanding the phenomena controlling slag formation and means to promote it were shortly reviewed. Thermodynamic constraints in slag formation were examined and the influence of fluxing additions was experimentally stated. Prefabricated “self-fluxing” lime was tested in industrial scale and proved to be a potential slag forming agent. Slag formation in secondary metallurgy and reduction of slag with aluminum dross or granules were experienced, and the effect on desulfurization and steel cleanliness was discussed.
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©2016 by De Gruyter
Articles in the same Issue
- Frontmatter
- An Experimental and Numerical Study on Orthogonal Machining of Ti–6Al–4V Alloy
- Formation of Chromium-Containing Molten Salt Phase during Roasting of Chromite Ore with Sodium and Potassium Hydroxides
- Slag Formation – Thermodynamic Aspects and Experimental Observations
- A Slag Management Toolset for Determining Optimal Coal Gasification Temperatures
- A Review on Strategic Positioning of Bottleneck around the Customer Order Decoupling Point and Issues on Production Planning in Supply Chain
- Investigation on Effect of Machining Parameters of End Milling on Surface Finish and Temperature Using Taguchi Technique
- Multi-Objective Optimization of HAZ Characteristics for Submerged Arc Welding of Micro-Alloyed High Strength Pipeline Steel using GRA-PCA Approach
Articles in the same Issue
- Frontmatter
- An Experimental and Numerical Study on Orthogonal Machining of Ti–6Al–4V Alloy
- Formation of Chromium-Containing Molten Salt Phase during Roasting of Chromite Ore with Sodium and Potassium Hydroxides
- Slag Formation – Thermodynamic Aspects and Experimental Observations
- A Slag Management Toolset for Determining Optimal Coal Gasification Temperatures
- A Review on Strategic Positioning of Bottleneck around the Customer Order Decoupling Point and Issues on Production Planning in Supply Chain
- Investigation on Effect of Machining Parameters of End Milling on Surface Finish and Temperature Using Taguchi Technique
- Multi-Objective Optimization of HAZ Characteristics for Submerged Arc Welding of Micro-Alloyed High Strength Pipeline Steel using GRA-PCA Approach
