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Translated by Li Qingyi. Price: ¥38.00; Jinqiao price: ¥36.10; Savings: ¥1.90. Publication date: 01-01-2009. Publisher: Metallurgical Industry Press. Author: R&D Carbon Ltd. (Switzerland). ISBN: 9787502447632. Edition: 1. Format: 16mo. Number of pages: 168. Book description: This book contains technical information from R&D Carbon Ltd., which represents the highest international standards in this field, as well as data on international carbon technologies for aluminum production and the results of doctoral research conducted at R&D Carbon Ltd. Chapter 1 of this book describes the process of producing aluminum using the Hall-Héroult electrolysis method. The production process of the anode is discussed in detail, starting from the raw materials used in production. Subsequently, an analysis of carbon consumption data was conducted to reveal its impact on the production costs of electrolytic aluminum and the importance of producing high-quality anodes. Chapter 2 focuses on the determination of the physicochemical properties of anodes, including explanations of all testing methods, thereby illustrating how the performance of anodes is influenced by the quality of raw materials and the anode manufacturing process. Chapter 3 addresses the fracture mechanics issues of carbon anodes, and explains how to apply various methods developed in the ceramics industry for analysis. Chapter 4 deals with the issue of thermal shock resistance of the anode when used in electrolyzers. Chapter 5 summarizes the findings from the previous chapters. In order to verify these theories one by one, they are applied in actual factories in this chapter to discuss the issue of anode cracking in practice. Chapter 6 discusses issues related to pre-baked anodes for aluminum in the future. Table of Contents: 1 Production of carbon anodes for aluminum 1.1 Production of electrolytic aluminum 1.1.1 Introduction 1.1.2 Production of alumina by the Bayer process 1.1.3 Electrolysis of aluminum by the Hall–Héroult process 1.2 Anode raw materials 1.2.1 Materials used in anode manufacturing 1.2.2 Petroleum coke 1.2.3 Coal tar binders 1.3 Production process of anodes 1.3.1 Introduction 1.3.2 Preparation of anode paste 1.3.3 Molding of the anode paste 1.3.4 Roasting of anodes 1.3.5 Casting of anodes 1.4 Production of electrolytic aluminum and anode consumption 1.4.1 Introduction 1.4.2 Electrochemical consumption of anodes 1.4.3 Chemical consumption of anodes 1.4.4 Physical consumption of anodes 1.4.5 Total anode consumption 1.4.6 Economic considerations 2 Description of anodes 2.1 Sampling and testing of anodes 2.2 Microstructure of anodes 2.2.1 Determination of carbon crystal structure and optical properties 2.2.2 Porosity 2.3 Physicochemical properties of anodes 2.3.1 Volume density 2.3.2 Specific resistance 2.3.3 Flexural strength 2.3.4 Compressive strength 2.3.5 Static elastic modulus 2.3.6 Dynamic elastic modulus 2.3.7 Fracture energy 2.3.8 Thermal expansion 2.3.9 Thermal conductivity 2.3.10 Measurement of density using the xylene method 2.3.11 Gas permeability 2.3.12 Reactivity with carbon dioxide 2.3.13 Reactivity with air 2.4 Influence of raw material quality on anode performance 2.4.1 Evaluation of coke using electrodes produced in the laboratory 2.4.2 Mixing optimization experiments 2.5 Influence of manufacturing process parameters on anode performance 2.5.1 Optimization of the anode manufacturing process 2.5.2 Influence of anode formulation and processing parameters 2.5.3 Influence of the final roasting temperature of anodes 2.5.4 Selection of optimization parameters 3 Fracture mechanics 3.1 Basic knowledge of fracture behavior in brittle materials 3.2 Energy methods 3.2.1 Effect of crack stress concentration 3.2.2 Griffith’s energy balance method 3.2.3 Linear elastic properties: energy release rate 3.2.4 Nonlinear properties: J-integral profile 3.2.5 Inelastic properties: instability and R-curve (crack resistance curve) 3.3 Stress concentration methods 3.3.1 Irwin’s analysis method 3.3.2 Displacement at the crack tip 3.4 Toughening mechanisms 3.4.1 Deflection and bending of cracks 3.4.2 Microcracks 3.4.3 Crack scaffolding (bridge bonds) 3.5 Measurement of fracture parameters in practice 3.6 Statistical analysis of fracture experiment data 3.6.1 Influence of defect size on material strength 3.6.2 Principle and application of the Weibull distribution function 4 Heat shock resistance 4.1 Sources of thermal stress 4.2 Thermelastic model proposed by Kingery 4.3 Energy method proposed by Hasselman 4.4 Heat shock resistance of anodes 4.4.1 Basic knowledge regarding heat shock resistance of anodes in electrolyzers 4.4.2 Heat shock resistance index 4.4.3 Physical derivation of the TSR index for anodes 4.4.4 Measurement of the TSR index in practice 5 Cracking of anodes 5.1 Types of crack structures 5.1.1 Corner cracks 5.1.2 Vertical cracks 5.1.3 Horizontal cracks 5.1.4 Influence of heat shock 5.2 Cracking resulting from raw anode manufacturing 5.2.1 Preparation and mixing of dry aggregates 5.2.2 Molding of the paste 5.2.3 Cooling of the green mass 5.3 Cracks occurring during roasting 5.3.1 First stage: Stress generated by release 5.3.2 Second stage: Cracks caused by stress release due to the liquefaction and volatilization of asphalt 5.3.3 Final roasting temperature 5.4 Cracking caused by anode casting and the design of steel claws 5.4.1 Geometry of anodes 5.4.2 Casting parameters 5.4.3 Thermal expansion of the steel claw framework 5.5 Cracking caused by heat shock in electrolyzers 5.5.1 Temperature difference between the electrolyzer and the anode 5.5.2 Movement of metal and electrolyte due to magnetic field effects and convection 5.5.3 Immersion depth of the anode and anode dimensions 6 Conclusions and prospects 6.1 Two main objectives 6.2 Future development trends 6.3 Methods to improve heat shock resistance of anodes Appendix 1 Calculations 1.1 Bending stress on the carbon bowl (see Chapter 5, Section 5.4.1) 1.2 Tensile stress around the carbon bowl (Chapter 5, Section 5.4.2) 1.3 Tensile stress between carbon bowls (Chapter 5, Section 5.4.3) 1.4 Factors affecting heat shock resistance (TSR) 2 Results of surveys on the heat shock resistance of anodes worldwide 2.1 Plant A: Batch No. 1 and Batch No. 2 2.2 Plant B: Batch No. 3 and Batch No. 4 2.3 Plant C: Batch No. 5 and Batch No. 6 2.4 Plant D: Batch No. 7 2.5 Plant E: Batch No. 8 2.6 Plant F: Batch No. 9 2.7 Plant G: Batch No. 7 2.8 Plant H 2.9 Data sheet Subject Index References