High Temperature Physicochemical Properties of High Alumina Blast Furnace Slag

This book presents the physicochemical properties and structure of high-alumina slag in the ironmaking process. The book consists of seven chapters demonstrating the effect of Al2O3 on the properties and structure of slag. Based on experimental research and practical requirements, a revolutionary technical route for blast furnace smelting of high-alumina iron ore is proposed. The book presents the scientific basis and offers theoretical guidance for the large-scale utilization of high-alumina iron ore in ironmaking process. Therefore, it is of interest for not only academic researchers but also practitioners in this field. Preface Contents 1 Introduction 1.1 Metallurgical Slag 1.2 Blast Furnace Process 1.2.1 Process Outline 1.2.2 Formation of Blast Furnace Slag 1.3 The Main Physicochemical Properties of Blast Furnace Slag 1.3.1 Liquids Temperature and Fluidity Temperature 1.3.2 Viscosity 1.3.3 Density 1.3.4 Surface Properties 1.3.5 Sulfide Capacity 1.3.6 Electrical Conductivity 1.4 Blast Furnace Ironmaking Requirements for Slag Properties References 2 Phase Diagram and Equilibrium 2.1 CaO–SiO2 2.2 CaO–Al2O3 2.3 Al2O3–SiO2 2.4 CaO–SiO2–Al2O3 2.5 CaO–SiO2–Al2O3–MgO References 3 Slag Structure of High Alumina Blast Furnace Slag 3.1 Basic Concepts of Slag Structure 3.1.1 Components and Classification of the Blast Furnace Slag 3.1.2 Composite Anions in the Slag 3.2 Parameters to Represent the Structure of Slags 3.2.1 Basicity (R) 3.2.2 Optical Basicity (Λ) 3.2.3 Bridging Oxygen (O0), Non-bridging Oxygen (O−) and Free Oxygen (O2−) 3.2.4 NBO/T(Q) and Qn 3.3 Characterization Methods of Slag Structure 3.4 Structure of Silicate 3.5 Structure of Aluminosilicate Blast Furnace Slag 3.6 Effect of Alumina on the Structure of Blast Furnace Slag 3.6.1 Molecular Dynamics Simulation 3.6.2 Analysis of Slag Structure by Raman Spectroscopy References 4 High-Temperature Physicochemical Properties of High Alumina Slag 4.1 Liquids Temperature and Fluidity Temperature 4.2 Viscosity 4.2.1 Effect of Al2O3 Content 4.2.2 Effect of Al2O3 ↔ SiO2 Substitution 4.2.3 Relationship Between Slag Viscosity and Its Structure 4.3 Density 4.4 Surface Tension 4.5 Sulfide Capacity 4.5.1 The Effect of Al2O3 Content and SiO2 ↔ Al2O3 Substitution on the Slag Sulfide Capacity 4.5.2 Relationship Between Sulfide Capacity and Structure 4.6 Electrical Conductivity 4.7 Summary References 5 Estimation of High Alumina Blast Furnace Slag Properties 5.1 Types of Estimation Models 5.1.1 Numerical Fitting Models 5.1.2 Thermodynamic Models 5.1.3 Structural-Based Models 5.1.4 Computer Simulations 5.1.5 Artificial Neural Network Model (ANN) 5.2 Liquidus and Solidus Temperatures 5.3 Viscosity 5.3.1 Overview of Viscosity Models 5.3.2 Structure-Based Viscosity Modeling 5.3.3 Iso-viscosity of High Alumina Blast Furnace Slag 5.4 Density 5.4.1 Overview of Density Models 5.4.2 Density of High Alumina Blast Furnace Slag 5.5 Surface Tension 5.5.1 Overview of Surface Tension Models 5.5.2 Iso-surface Tension of High Alumina Blast Furnace Slag 5.6 Sulfide Capacity 5.6.1 Overview of Sulfide Capacity Models 5.6.2 Structure-Based Sulfide Capacity Modeling 5.6.3 Iso-sulfide Capacity of High Alumina Blast Furnace Slag 5.7 Electrical Conductivity 5.7.1 Overview of Electrical Conductivity Models 5.7.2 Iso-electrical Conductivity of High Alumina Blast Furnace Slag Appendix References 6 The Revolution of High Alumina Slag in Blast Furnace Process 6.1 The Inevitability of High Alumina Blast Furnace Slag 6.1.1 Iron and Steel Industry in the World 6.1.2 Iron Ore Resources 6.2 Current Technical Routes for High Alumina Blast Furnace Slag 6.2.1 Basicity Control 6.2.2 MgO/Al2O3 Control 6.3 Feasibility of Revolution High Alumina Blast Furnace Slag 6.3.1 Slag-Metal Separation 6.3.2 Hot Metal Quality Control 6.4 Summary References