Title Details

ALAN TOMSETT, PhD, is Technical Director for the Pacific Technology Center, Pacific Aluminum, where he provides technical support and advice to the Pacific Aluminum smelters. Dr. Tomsett has more than twenty-five years of experience in carbon anode and cathode technology.

JOHN JOHNSON, MS, heads his own consulting business. He has forty-two years of experience in the aluminum industry, specializing in prebake and VSS anode technology as well as prebake cell design and development. Mr. Johnson was the Editor of Light Metals 2010.

Preface xv

Lead Editors xix

Editorial Team xxi

Part 1: Hall-Héroult Cell Carbon Anodes

Section Introduction 1

Raw Materials: Coke

Calcined Coke from Crude Oil to Customer Silo 3
B. Vitchus, F. Cannova, and H. Childs

Refinery Feedstocks, Coke Structures and Aluminum Cell Anodes 11
P. Rhedey and D. DuTremblay

Coker Feedstock Characteristics and Calcined Coke Properties 19
P. Rhedey and S. Nadkarni

Quality and Process Performance of Rotary Kilns and Shaft Calciners 24
L. Edwards

High Vanadium Venezuelan Petroleum Coke, A Rawmaterial for the Aluminum Industry? 30
U. Mannweiler, W. Schmidt-Hatting, D. Rodriguez, and A. Maitland

Use of Shot Coke as an Anode Raw Material 36
L. Edwards, F. Vogt, M. Robinette, R. Love, A. Ross, M. McClung, R. Roush, and W. Morgan

Influence of High Sulphur Cokes on Anode Performance 42
S. Jones, R. Hildebrandt, and M. Hedlund

Carbon Raw Material Effects on Aluminum Reduction Cell Anodes 53
P. Rhedey and S. Nadkarni

A Comprehensive Determination of Effects of Calcined Petroleum Coke Properties on Aluminum Reduction Cell Anode Properties 59
D. Belitskus and D. Danka

A Comprehensive Review of the Effects of Calcination at Various Temperatures on Coke Structure and Properties _ Part 2 73
E. Hardin, C. Beilharz, P. Ellis, and L. McCoy

Influence of Coke Real Density on Anode Reactivity Consequence on Anode Baking 84
B. Coste and J. Schneider

Coke Calcination Levels and Aluminum Anode Quality 93
C. Dreyer, B. Samanos, and F. Vogt

Impact of Coke Calcination Level and Anode Baking Temperature on Anode Properties 101
B. Samanos and C. Dreyer

Use of Under-Calcined Coke for the Production of Low Reactivity Anodes 109
J. Lhuissier, L. Bezamanifary, M. Gendre, and M. Chollier

Anode Filler Coke Porosity Studies 114
P. Rhedey

Desulphurization and Its Effect on Calcined Coke Properties 119
R. Garbarino and R. Tonti

Influence of Petroleum Coke Sulphur Content on the Sodium Sensitivity of Carbon Anodes 123
S. Hume, W. Fischer, R. Perruchoud, J. Metson, and R. Baker

A Review of Coke and Anode Desulfurization 130
L. Edwards, K. Neyrey, and L. Lossius

Coke and Anode Desulfurization Studies 136
L. Lossius, K. Neyrey, and L. Edwards

Minimizing Impact of Low Sulfur Coke on Anode Quality 142
A. Adams, R. Cahill, Y. Belzile, K. Cantin, and M. Gendron

Evaluating Calcined Coke for Aluminum Smelting by Bulk Density 148
D. Belitskus

Maintaining Consistent Anode Density Using Varying Carbon Raw Materials 156
S. Wilkening

Coke Blending and Fines Circuit Targeting at the Alcoa Deschambault Smelter 163
M. Gendron, S. Whelan, and K. Cantin

Raw Materials: Pitch

Worldwide Pitch Quality for Prebaked Anodes 167
R. Perruchoud, M. Meier, and W. Fischer

Coal Tar Pitch _ Past, Present, and Future 177
J. Baron, S. McKinney, and R. Wombles

Electrode Binder Pyrolysis and Bond-Coke Microstructure 182
S. Jones and R. Hildebrandt

Binder for the Ideal Anode Carbon 198
S. Jones and E. Bart

Binding Characteristics of Coal Tar Pitches for Prebaked Anode Mix - Choice Criteria: LRF Report 830 215
J. Pinoir and P. Hyvernat

The Influence of Solid Particles in Pitch on the Preparation and Baking of the Carbon Blocks 225
G. Romovacek

Performance of Binder Pitches With Decreased QI-Content in Anode Making: Formation - Nature - Properties and Substitution of Quinoline Insolubles 232
A. Alscher, R. Wildförster, and J. Sharp

Temperature Stability of Søderberg Anode Pitch 239
M. Sørlie

Developing Coal Tar/Petroleum Pitches 246
R. Wombles and M. Kiser

Raw Materials: Spent Carbon

Investigation of the Quality of Recycled Anode Butts 251
W. Schmidt-Hatting, A. Kooijman, and R. Perruchoud

Interdependence Between Properties of Anode Butts and Quality of Prebaked Anodes 267
W. Fischer and R. Perruchoud

Raw Material and Anode Characterization

New Methods for Testing Raw Materials for Anode Carbon Paste 271
O. Bowitz, T. Eftestol, and R. Selvik

Standardization of a Calcined Coke Bulk Density Test 281
D. Belitskus

Reactivity Testing of Anode Carbon Materials 290
G. Houston and H. Øye

Characterization of Prebaked Anode Carbon by Mechanical and Thermal Properties 298
J. Brown and P. Rhedey

Green Anode Production

Aggregate Optimization Using a Y-Blender 307
R. Peterson

Soderberg Paste. Effect of Fine Fraction Variations 313
P. Stokka and I. Skogland

Finer Fines in Anode Formulation 318
F. Figueiredo, C. Cato, A. Nascimento, A. Marques, and P. Miotto

Process Adaptations for Finer Dust Formulations: Mixing and Forming 322
K. Hulse, R. Perruchoud, W. Fischer, and B. Welch

Effects of Mixing Variables and Mold Temperature on Prebaked Anode Quality 328
D. Belitskus

Improving Anode Quality by Separately Optimising Mixing and Compacting Temperature 333
B. Coste

Vibration Forming of Carbon Blocks 339
E. Sandvik, R. Blindheim, and H. Bø

Cooling of Green Anodes After Forming 351
W. Fischer, M. Meier, and M. Lustenberger

Recent Improvement in Paste Plant Design: Industrial Application and Results 358
C. Vanvoren

Going Beyond SPC _ Why We Need Statistical Thinking in Operations Such as Carbon Plants 365
K. Sinclair and B. Sadler

Properties and Behaviour of Green Anodes 371
S. Wilkening

Potentialities in the Paste Plant 378
S. Wilkening

Baked Anode Production

Mathematical Simulation of a Horizontal Flue Ring Furnace 386
R. Bui, E. Dernedde, A. Charette, and T. Bourgeois

Flue Gas Management 390
W. Leisenberg

Safe Operation of Anode Baking Furnaces 396
I. Holden, O. Saeter, F. Aune, and T. Naterstad

Anode Baking: The Underestimated Human Aspect 403
F. Keller, P. Sulger, and W. Fischer

Specific Energy Consumption in Anode Bake Furnaces 408
F. Keller, P. Sulger, M. Meier, D. Severo, and V. Gusberti

Evaluation of the Uniformity of Baking in Horizontal and Vertical Flue Ring Furnaces 414
D. Holdner, S. Nadkarni, and D. DuTremblay

Measurement and Control of the Calcining Level in Anode Baking Furnaces 418
T. Foosnaes, N. Kulset, H. Linga, G. Naeumann, and A. Werge-Olsen

The Equivalent Temperature Method for Measuring the Baking Level of Anodes 422
L. Lossius, I. Holden, and H. Linga

Baking Parameters and the Resulting Anode Quality 427
W. Fischer, F. Keller, R. Perruchoud, and S. Oderbolz

Anode Desulphurization on Baking 434
M. Vogt, K. Ries, and M. Smith

The Effect of Prebake Anode Baking Temperature on Potroom Performance 444
G. Bain, J. Pruneau, and J. Williams

Influence of Baking Temperature and Anode Effects Upon Carbon Sloughing 450
E. Cutshall and V. Bullough

Influence on Anode Baking Temperature and Current Density Upon Carbon Sloughing 469
E. Cutshall

Anode Reactivity Influence of the Baking Process 478
C. Dreyer

Modern Anode Baking Furnace Developments 486
F. Keller and J. Disselhorst

Strategies for the Revision of Bake Furnaces 492
F. Keller

Rodded Anode Production and Anode Design

Temperature and Voltage Measurements in Hall Cell Anodes 500
R. Peterson

Studies of Stub to Carbon Voltage 510
R. Peterson

Factors in the Design of Reduction Cell Anodes 516
D. Brooks and V. Bullough

Anode Cast Iron Thickness Optimization 524
M. Ohlswager, G. Goeres, and R. Peterson

Drilling of Stub Holes in Prebaked Anodes 529
B. Aga, I. Holden, H. Linga, and K. Solbu

Problems of the Stub-Anode Connection 534
S. Wilkening and J. Côté

Challenges in Stub Hole Optimisation of Cast Iron Rodded Anodes 543
D. Richard, P. Goulet, O. Trempe, M. Dupuis, and M. Fafard

Real Time Temperature Distribution during Sealing Process and Room Temperature Air Gap Measurements of a Hall- Héroult Cell Anode 549
O. Trempe, D. Larouche, D. Ziegler, M. Guillot, and M. Fafard

Effects of Carbonaceous Rodding Mix Formulation on Steel-Carbon Contact Resistance 555
P. Rhedey and L. Castonguay

Anode Performance: Reactivity Fundamentals

Anode Carbon Reactivity 564
S. Jones and R. Hildebrandt

Studies on Anode Reactivity to Oxidant Gases 580
J. Rey Boero

Some Practical Consequences of Analyses of the Carboxy and Airburn Reactions of Anode Carbons 589
N. Bird, B. McEnaney, and B. Sadler

A Porosimetric Study of Sub-Surface Carboxy Oxidation in Anodes 594
B. Sadler and S. Algie

Studies of the Impact of Vanadium and Sodium on the Air Reactivity of Coke and Anodes 606
J. Rolle and Y. Hoang

Anode Performance: Dusting

A Review of Factors Affecting Carbon Anode Consumption in the Electrolytic Production of Aluminum 611
P. Rhedey

Reflections on the Carbon Consumption of Prebaked Anodes 623
S. Wilkening

Anode Dusting in Hall-Heroult Cells 633
T. Foosnaes, T. Naterstad, M. Bruheim, and K. Grjotheim

The Influence of Low Current Densities on Anode Performance 643
S. Hume, M. Utley, B. Welch, and R. Perruchoud

Dust Generation and Accumulation for Changing Anode Quality and Cell Parameters 649
R. Perruchoud, K. Hulse, W. Fischer, and W. Schmidt-Hatting

Anode Dusting from a Potroom Perspective at Nordural and Correlation with Anode Properties 657
H. Gudmundsson

The Reduction in Anode Airburn with Protective Covers 663
A. Fitchett, D. Morgan, and B. Welch

Reactivity and Electrolytic Consumption of Anode Carbon with Various Additives 667
T. Müftüo_lu and H. Øye

Bath Impregnation of Carbon Anodes 673
R. Perruchoud, M. Meier, and W. Fischer

Anode Performance: Thermal Shock

Effects of Coke and Formulation Variables on Cracking of Bench Scale Prebaked Anode Specimens 680
D. Belitskus

Thermal Shock in Anodes for the Electrolytic Production of Aluminium 687
E. Kummer and W. Schmidt-Hatting

Operating Parameters Affecting Thermal Shock Cracking of Anodes in the Valco Smelter 694
N. Ambenne and K. Ries

Thermal Shock of Anodes _ A Solved Problem? 700
M. Meier, W. Fischer, R. Perruchoud, and L. Gauckler

Extrinsic and Intrinsic Aspects of Anode Cracking 710
T. Liu, L. Edwards, C. Hughes, B. Mason, and R. McMellon

An Approach for a Complete Evaluation of Resistance to Thermal Shock (Part 1): Applying to the Case of
Anodes and Cathodes 717
C. Dreyer and B. Samanos

Finite Element Modelling of Thermal Stress in Anodes 723
P. Cook

Recommended Reading 731

Part 2: Hall-Héroult Cell Cathodes

Section Introduction 739

Cell Lining: Cathodes

ISO Standards for Testing of Cathode Materials 741
H. Øye

Laboratory Testing of Carbon Cathode Materials at Operational Temperatures 747
M. Sørlie and H. Øye

Structural Changes in Carbon by Heat Treatment 754
S. Brandtzaeg, H. Linga, and H. Øye

Low Electrical Resistivity and High Thermal Conductivity Carbon Products: The Solution for Cell Lining 762
D. Dumas and C. Michel

Aluminium Pechiney Experience with Graphitized Cathode Blocks 773
D. Lombard, T. Béhérégaray, B. Fève, and J. Jolas

Some Experiments in Cathode Carbon 779
S. Wilkening

How to Improve the Pig Iron Sealing of Metallic Bars in Cathode Carbon Blocks 787
I. Letizia, C. Bizzarri, and M. Lezzerini

Stress Analysis of Cathode Bottom Blocks 793
B. Larsen and M. Sørlie

Experimental Comparison of Cathode Rodding Practices 799
L. Caruso, K. Rye, and M. Sørlie

Cell Lining: Ramming Paste

Compaction of Room Temperature Ramming Paste 804
M. Sørlie and H. Øye

Densification of Ramming Paste in Cathodes 814
M. Sørlie, B. Faaness , and J. Belmonte

Investigation into the Expansion/Contraction Behaviour of Cold Ramming Pastes during Baking Using a Horizontal Dilatometer Method 821
B. Hocking

Ramming Paste Related Failures in Cathode Linings 827
B. Faaness, H. Gran, M. Sørlie, and H. Øye

Cell Lining: Refractories

Corrosion and Behaviour of Fireclay Bricks of Varying Chemical Composition Used in the Bottom Lining of Reduction Cells 834
F. Brunk

Experiences with Dry Barrier Powder Materials in Aluminium Electrolysis Cells 840
O.-J. Siljan, O. Junge, T. Svendsen, and K. Thovsen

Cathode Refractory Materials for Aluminium Reduction Cells 849
C. Schøning, T. Grande, and O. Siljan

Evaluation of Silicon Carbide Bricks 857
A. Tabereaux and A. Fickel

Quality Evaluation of Nitride Bonded Silicon Carbide Sidelining Materials 866
E. Skybakmoen, L. Stoen, J. Kvello, and O. Darell

SiC in Electrolysis Pots: An Update 872
R. Pawlek

Thermal Insulation Materials for Reduction Cell Cathodes 876
A. Tabereaux

Cathode Performance: Failure Modes

Use of Cell Autopsy to Diagnose Potlining Problems 888
R. Jeltsch

Processes Occurring in the Carbon Lining of an Aluminum Reduction Cell 894
J. Waddington

A Study of Some Aspects of the Influence of Cell Operation on Cathode Life 903
C. Clelland, J. Keniry, and B. Welch

Potlining Failure Modes 909
M. Dell

Design of Highly Reliable Pot Linings 914
J. Peyneau

Early Failure Mechanisms in Aluminium Cell Cathodes 921
M., J. Hvistendahl, and H. Øye

A Comparative Examination of Ageing of Cathodes: Amorphous Versus Graphitic Type 931
E. Berhauser and J. Mittag

Property Changes of Cathode Lining Materials during Cell Operation 936
M. Sørlie, H. Gran, and H. Øye

Cathode Performance: Chemical Reactions

Reaction Between Carbon Lining and Hall Bath 946
M. Dell

Penetration of Sodium and Bath Constituents into Cathode Carbon Materials Used in Industrial Cells 953
C. Krohn, M. Sorlie, and H. Øye

Chemical Resistance of Cathode Carbon Materials during Electrolysis 960
M. Sørlie and H. Øye

The Effect of Current Density on Cathode Expansion during Start-Up 966
A. Ratvik, A. Støre, A. Solheim, and T. Foosnaes

Reactions in the Bottom Lining of Aluminium Reduction Cells 972
A. Solheim, C. Schøning, and E. Skybakmoen

Chemical Degradation Map for Sodium Attack in Refractory Linings 978
K. Tschöpe, J. Rutlin, T. Grande

Cathode Performance: Erosion

Physical and Chemical Wear of Carbon Cathode Materials 984
X. Liao and H. Øye

Carbon Cathode Corrosion by Aluminium Carbide Formation in Cryolitic Melts 992
X. Liao and H. Øye

Erosion of Cathode Blocks in 180 kA Prebake Cells 999
A. Tabereaux, J. Brown, I. Eldridge, and T. Alcorn

Graphite Cathode Wear Study at Alouette 1005
P. Reny and S. Wilkening

Electrolytic Degradation within Cathode Materials 1011
P. Rafiei, F. Hiltmann, M. Hyland, B. James, and B. Welch

Influence of Internal Cathode Structure on Behavior during Electrolysis Part II: Porosity and Wear Mechanisms in Graphitized Cathode Materials 1017
P. Patel, M. Hyland, and F. Hiltmann

Influence of Internal Cathode Structure on Behavior during Electrolysis Part III: Wear Behavior in Graphitic Materials 1023
P. Patel, M. Hyland, and F. Hiltmann

Spent Pot Lining

Formation and Distribution of Cyanide in the Lining of Aluminum Reduction Cells 1029
R. Peterson, L. Blayden, and E. Martin

Potlining Flux in Making Steel 1037
D. Augood, R. Schlager, and P. Belding

Thermal Treatment of Spent Potliner in a Rotary Kiln 1044
D. Brooks, E. Cutshall, D. Banker, and D. Strahan

Treatment and Reuse of Spent Pot Lining, an Industrial Application in a Cement Kiln 1049
P. Personnet

Co-Processing at Cement Plant of Spent Potlining from the Aluminum Industry 1057
V. Gomes, P. Drumond, J. Neto, and A. Lira

Development Status of Processing Technology for Spent Potlining in China 1064
W. Li and X. Chen

Recommended Reading 1067

Part 3: Inert Anodes and Wettable Cathodes

Section Introduction 1071

Inert Anodes

Solubilities of Oxides for Inert Anodes in Cryolite-Based Melts 1073
D. DeYoung

Corrosion and Passivation of Cermet Inert Anodes in Cryolite-Type Electrolytes 1082
G. Tarcy

Testing of Cerium Oxide Coated Cermet Anodes in a Laboratory Cell 1094
J. Gregg, M. Frederick, H. King, and A. Vaccaro

A Non-Consumable Metal Anode for Production of Aluminum with Low Temperature Fluoride Melts 1104
T. Beck

The Behaviour of Nickel Ferrite Cermet Materials as Inert Anodes 1110
E. Olsen and J. Thonstad

Tin Dioxide-Based Ceramics as Inert Anodes for Aluminium Smelting: A Laboratory Study 1119
A. Vecchio-Sadus, D. Constable, R. Dorin, E. Frazer, I. Fernandez, G. Neal, S. Lathabai, and M. Trigg

Inert Anodes: An Update 1126
R. Pawlek

Wettable Cathodes

The Application of the Refractory Carbides and Borides to Aluminum Reduction Cells 1134
C. Ransley

Use of TiB2 Cathode Material: Application and Benefits in Conventional VSS Cells 1145
L. Boxall, A. Cooke, and H. Hayden

Use of TiB2 Cathode Material: Demonstrated Energy Conservation in VSS Cells 1153
A. Cooke and W. Buchta

A Review of RHM Cathode Development 1164
C. McMinn

Properties of a Colloidal Alumina-Bonded TiB2 Coating on Cathode Carbon Materials 1171
H. Øye, V. de Nora, J. Duruz, and G. Johnston

Sodium and Bath Penetration into TiB2-Carbon Cathodes during Laboratory Aluminium Electrolysis 1179
J. Xue and H. Øye

Wettable Cathodes: An Update 1185
R. Pawlek

Recommended Reading 1191

Author Index. 1193