The most up-to-date and timely treatment on cathodic protection available.
Table of Contents Acknowledgements
Preface
1 Corrosion of Materials
1.1 Deterioration or Corrosion of Ceramic Materials
1.2 Degradation or Deterioration of Polymers
1.3 Corrosion or Deterioration of Metals
1.3.1 Iron, Steel and Stainless Steels
1.3.2 Aluminum and Its Alloys
1.3.3 Magnesium and Its Alloys
1.3.4 Copper and Its Alloys
1.3.5 Nickel and Its Alloys--‚¬--
1.3.6 Titanium and Its Alloys
1.3.7 Lead and Its Alloys
1.3.8 Composite Alloys
2 Factors Influencing Corrosion
2.1 Nature of the Metal
2.1.1 Position in Galvanic Series
2.1.2 Relative Areas of the Anode and Cathode
2.1.3 Purity of Metal
2.1.4 Physical State of the Metal
2.1.5 Passivity or Passivation
2.1.6 Nature of the Corrosion Product of the Metal
2.1.7 Nature of the Oxide Film of the Metal
2.2 Nature of the Corroding Environment
2.2.1 Effect of Temperature
2.2.2 Dissolved Oxygen Concentration and Formation of Oxygen Concentration Cells
2.2.3 Nature of the Electrolyte
2.2.4 Presence of Aggressive Anions
2.2.5 Flow Rate
2.2.6 Humidity
2.2.7 Effect of pH
2.2.8 Presence of Impurities in the Atmosphere
3 Corrosion Mechanisms
3.1 Direct Chemical Attack or Chemical or Dry Corrosion
3.1.1 Oxidation Corrosion
3.1.2 Corrosion by Other Gases
3.1.3 Liquid Metal Corrosion
3.2 Electrochemical or Aqueous or Wet Corrosion
3.3 Differences between Chemical and Electrochemical Corrosion
4 Types of Corrosion
4.1 Uniform Corrosion
4.1.1 Atmospheric Corrosion
4.1.2 Corrosion in Seawater and in Fresh Waters
4.1.3 Underground or Soil Corrosion.
4.1.4 High Temperature Corrosion
4.2 Non-Uniform Corrosion
4.2.1 Galvanic Corrosion
4.2.2 Crevice Corrosion
4.2.3 Pitting Corrosion
4.2.4 Selective Leaching or Selective Corrosion
4.2.5 Filiform Corrosion
4.2.6 Erosion Corrosion
4.2.7 Cavitation Corrosion
4.2.8 Abrasion Corrosion
4.2.9 Stress Corrosion
4.2.10 Intergranular Corrosion
4.2.11 Caustic Embrittlement
4.2.12 Hydrogen Embrittlement
4.2.13 Corrosion Fatigue
4.2.14 Fretting Corrosion
4.2.15 Stray-current and Interference Corrosion
4.2.16 Waterline Corrosion
4.2.17 Microbial or Biocorrosion
5 Thermodynamics of Corrosion
5.1 Gibbs Free Energy ( Ž€G)--‚¬--
5.2 Passivity
5.3 Pourbaix Diagrams
5.3.1 Immunity Region
5.3.2 Corrosion Regions
5.3.3 Passivity Region
5.4 Corrosion Equilibrium and Adsorptions
5.5 Concentration Corrosion Cells
5.6 Polarization
5.6.1 Activation Polarization
5.6.2 Concentration Polarization
5.6.3 Ohmic Polarization
5.7 Polarization Curves
6 Corrosion Prevention and Protection
6.1 Proper Design
6.2 Choice of Material
6.2.1 Purity of the Chemicals in the Environment
6.2.2 Electrolyte Concentrations
6.2.3 Nature of the Electrolyte
6.2.4 Effect of Corrosion Products
6.2.5 Temperature Variations
6.2.6 Presence of Oxygen
6.2.7 Oxygen Concentration Cells.. 90
6.2.8 Interference Effects
6.3 Protective Coatings
6.3.1 Protective Oxide Films and Passivation
6.3.2 Coatings with Metals, Alloys or Materials that are Conductors
6.3.3 Coatings with Inorganic Materials that are Insulators
6.3.4 Coatings with Organic Materials that are Insulators
6.4 Changing the Environmental Factors
6.4.1 Reducing the Corrosivity of the Solution
6.4.2 Inhibitors
6.4.3 Eliminating Galvanic Action
6.5 Changing the Electrochemical Characteristic of the Metal Surface
6.5.1 Cathodic Protection
6.5.2 Anodic Protection
7 Cost of Corrosion
7.1 Corrosion Preventative Measures
7.2 Lost Production Due to Plants Going out of Service or Shutdowns
7.3 Product Loss Due to Leakages
7.4 Contamination of the Product
7.5 Maintenance Costs
7.6 Overprotective Measures
8 Cathodic Protection
8.1 Sacrificial Anode Cathodic Protection Systems
8.2 Impressed Current Cathodic Protection Systems
8.3 Cathodic Protection Current Need
8.4 Effect of Coatings on Cathodic Protection
8.5 Effect of Passivation on Cathodic Protection
8.6 Automated Cathodic Protection Systems
8.7 Cathodic Protection Criteria--‚¬--
8.7.1 -850 mV Criterion
8.7.2 300 mV Potential Shift Criterion
8.7.3 100 mV Polarization Shift Criterion
8.7.4 Tafel Region Starting Point
8.8 Reliability of Cathodic Protection Criteria
8.9 Interference Effects of Cathodic Protection Systems
8.9.1 Anodic Interference
8.9.2 Cathodic Interference
8.9.3 Specific Interference Cases
8.10 Criteria for Cathodic Protection Projects
8.11 Cost of Cathodic Protection
8.12 Comparison of Cathodic Protection Systems
9 Sacrificial Anode or Galvanic Cathodic Protection Systems
9.1 Anodic Potentials and Anodic Polarization
9.2 Galvanic Cathodic Protection Current Need
9.3 Anodic Current Capacity and Anodic Current Efficiency
9.4 Service Life of an Anode
9.5 Minimum Number of Galvanic Anodes
9.6 Commonly Used Galvanic Anodes
9.6.1 Magnesium Anodes
9.6.2 Zinc Anodes
9.6.3 Aluminum Anodes
9.7 Performance Measurements of Galvanic Anodes
9.7.1 Chemical Composition -‚ ---‚ ... --‚ ---‚ 100
9.7.2 Mechanical Strength ---‚ ... --‚ --‚¬-- 100
9.7.3 Electrical Resistivity ---‚ ... --‚ --‚¬-- 100
9.7.4 Electrochemical Experiments-- ---‚ ... --‚ ---‚ .100
9.8 Galvanic Anodic Beds ---‚ ... .100
9.8.1 Anodic Bed Filling Materials.-- ---‚ ... -‚ 100
9.8.2 Anodic Bed Resistance--‚ .-- ... --‚ --‚ 100
9.9 Sacrificial Anode Cathodic Protection Projects... ---‚ 100
9.10 Maintenance of Sacrificial Anode Cathodic Protection Systems -‚ 100
9.10.1 Low Pipeline/Terrain Potential-- ... --‚ --‚ 100
9.10.2 Decreases in Anodic Current Production. --‚ --‚¬-- 100
10 Impressed Current Cathodic Protection Systems.. -‚¬-- -- 100
10.1 T/R Units ---‚ ..... 100
10.1.1 Efficiency of T/R Units-- ... 100
10.1.2 T/R Units with Constant Potentials--‚ 100
10.1.3 Installation of T/R Units-- ---‚ --‚ 100
10.1.4 Technical Properties of T/R Units-- . 100
10.2 Types of Anodes ---‚ . .100
10.2.1 Graphite Anodes -‚ ... 100
10.2.2 Iron-Silicon Anodes -‚ .. -‚ . 100
10.2.3 Silver-Lead Anodes. -‚ .. -‚ . 100
10.2.4 Titanium Anodes Coated with Platinum.-- --‚ 100
10.2.5 Titanium Anodes Coated with Metal Oxides --‚ 100
10.3 Anodic Bed Resistance ---‚ 100
10.4 Types of Anodic Beds. ---‚ 100
10.5 Cable Cross-Sections ---‚ 100
10.6 Impressed Current Cathodic Protection Projects-- ---‚ 100
10.7 Maintenance of Impressed Current Cathodic Protection Systems--‚ .100
10.7.1 Periodical Measurements and Controls of the Entire System-- . -‚ .100
10.7.2 Periodical Measurements and Controls of the T/R Unit-- . -‚ 100
10.7.3 Commonly Encountered Problems--‚ 100
11 Corrosion and Corrosion Prevention of Concrete Structures-- 100
11.1 Concrete's Chemical Composition.-- 100
11.2 Corrosion Reactions of Concrete. ¬-- 100
11.3 Factors Affecting Corrosion Rate in Reinforced Concrete Structures -‚ .-- ---‚ 100
11.3.1 Effect of Concrete Composition... 100
11.3.2 Effect of Oxygen-- ..... 100
11.3.3 Effect of Humidity.-- ---‚ ..... ---‚ --‚ 100
11.3.4 Effect of Temperature-- ..... 100
11.3.5 Effect of pH -‚ . ---‚ ..... 100
11.3.6 Effect of Chlorides.-- ---‚ ..... 100
11.3.7 Effect of Magnesium Ions ..... 100
11.4 Corrosion Measurements in Reinforced Concrete Structures-- .--‚ .-- 100
11.4.1 Observational Methods-- ... 100
11.4.2 Weight Loss Measurements--‚ .... --‚ 100
11.4.3 Potential Diagrams-- .--‚ .... ---‚ --‚ 100
11.4.4 Polarization Curves... .. ---‚ --‚ 100
11.5 Corrosion Prevention of Reinforced Concrete.-- 100
11.5.1 Via Coatings-- ---‚ ... 100
11.5.2 Via Inhibitors ... ---‚ --‚ 100
11.5.3 Via Cathodic Protection... -‚ ... ---‚ --‚ 100
12 Cathodic Protection of Reinforced Concrete Steels... -‚ -- -‚ .100
12.1 Current Needed for Cathodic Protection of Steel Structures.. 100
12.2 Cathodic Protection Criteria 100
12.2.1 -770 mV Potential Criterion.--‚ ... 100
12.2.2 300 mV Potential Shift -‚ .. 100
12.2.3 100 mV Potential Shift -‚ .. 100
12.3 Determination of the Protection Potential. 100
12.4 Cathodic Protection Methods for Reinforced Concrete Steels-- ---‚ . -‚ ¬--100
12.4.1 Via Iron-Silicon Anodes--‚ ... 100
12.4.2 Via Conductive Polymeric Cage Anodes-- --‚ 100
12.4.3 Via Titanium Sieve Anodes Coated with Oxides --‚ 100
12.4.4 Via Conducting Paints. ... 100
12.5 Cathodic Protection of Pre-stressed Steel Concrete Pipes...... 100
13 Corrosion in Petroleum Industry-- ---‚ ... -‚ .100
13.1 Hydrochloric Acid (HCl) and Chlorides--‚ 100
13.2 Hydrogen (H2) Gas-- --‚ 100
13.3 Hydrogen Sulfide (H2S) and Other Sulfur Compounds .... 100
13.4 Sulfuric Acid (H2SO4)--‚ --‚ .... 100
13.5 Hydrogen Fluoride (HF) 100
13.6 Carbon Dioxide (CO2)... 100
13.7 Dissolved Oxygen (O2) and Water (H2O).--‚ .-- 100
13.8 Organic Acids 100
13.9 Nitrogen (N2) Compounds and Ammonia (NH3)--‚ .-- . 100
13.10 Phenols ---‚ .. 100
13.11 Phosphoric Acid (H3PO4)-- 100
13.12 Caustic Soda (NaOH)-- 100
13.13 Mercury (Hg) 100
13.14 Aluminum Chloride (AlCl3).--‚ . 100
13.15 Sulfate Reducing Bacteria (SRB)..... 100
14 Corrosion in Pipeline Systems--‚ ---‚ ... -‚ .100
14.1 Pipes Made of Iron and Its Alloys -‚ .--‚ 100
14.1.1 Cast Iron Pipes-- ... 100
14.1.2 Ductile Cast Iron Pipes-- .. -‚ 100
14.1.3 Steel Pipes-- .. -‚ 100
14.2 Petroleum or Crude Oil Pipeline Systems... 100
14.3 Water Pipeline Systems-- ---‚ .. 100
14.3.1 Water Pipelines Made of Iron and Steel --‚¬-- 100
14.3.2 Galvanized Water Pipelines-- ---‚ . --‚ 100
14.3.3 Water Pipelines Made of Copper -‚ . --‚ 100
14.3.4 Water Pipelines Made of Brass... -‚ . --‚¬-- 100
15 Cathodic Protection of Pipeline Systems--‚ ---‚ -‚ .100
15.1 Measurement of Terrain-- Resistivity.. 100
15.2 Potential Measurements 100
15.2.1 Redox Potential of the Terrain 100
15.2.2 Static Potential and On-Off Potentials. ---‚¬--100
15.2.3 Measurement of Pipeline/Terrain Potential 100
15.3 Determination of Coating Failures Based on Potential Measurements--‚ ..100
15.3.1 Determination of Coating Failures Based on the Measured Pipeline/Terrain Potentials... 100
15.3.2 Determination of Coating Failures Based on the Pearson Method 100
15.4 Measuring Potential along the Pipeline. 100
15.4.1 Long Cable Method 100
15.4.2 Double Electrode Method ---‚ ... 100
15.5 Maintenance of Pipeline Cathodic Protection Systems--‚ ....... 100
15.6 Measurement Stations 100
15.6.1 STP Regular Measurement Units--‚ ---‚ 100
15.6.2 ATP Current Measurement Units.-- 100
15.6.3 SATP Galvanic Anode Measurement Units--‚ 100
15.6.4 SIF Insulated Flange Measurement Units ---‚ 100
15.6.5 EPC Equivalent Potential Measurement Units 100
15.6.6 CTP Measurement Units -- ---‚ 100
15.7 Static Electricity and Its Prevention. ..... 100
15.8 Cathodic Protection of Airport Fuel Distribution Lines.......... 100
15.9 Cathodic Protection of Water Pipelines-- .......... 100
16 Corrosion and Cathodic Protection of Crude Oil or Petroleum Storage Tanks ...100
16.1 Corrosion of Crude Oil Storage Tanks..... ..... 100
16.2 Cathodic Protection of Crude Oil Storage Tanks.................... 100
16.2.1 Corrosion Prevention-- ---‚ 100
16.2.2 Sacrificial Anode Cathodic Protection.-- 100
16.2.3 Sacrificial Anode Cathodic Protection Current Need ¬--100
16.2.4 Problems with Cathodic Protection of Storage Tanks 100
17 Corrosion and Cathodic Protection of Metallic Structures in Seawater-- --‚¬--100
17.1 Factors Affecting Corrosion Rate of Metallic Structures in Seawater............... ......100
17.1.1 Effect of Resistivity on Corrosion in Seawater--‚ ---‚ 100
17.1.2 Effect of pH on Corrosion in Seawater-- ---‚ ---‚ 100
17.1.3 Effect of Temperature on Corrosion in Seawater 100
17.1.4 Effect of Dissolved Oxygen Concentration -‚ ---‚ 100
17.1.5 Effect of Fluid Rate ---‚ 100
17.2 Cathodic Protection of Metallic Structures in the Sea.............. 100
17.2.1 Cathodic Protection Current Need ---‚ 100
17.2.2 Cathodic Protection Criteria ---‚ 100
17.3 Cathodic Protection of Ships ............ ...100
17.3.1 Painting the Ships ---‚ 100
17.3.2 Sacrificial Anode Cathodic Protection of Ships........ 100
17.3.3 Impressed Current Cathodic Protection of Ships..... 100
17.3.4 General Guidelines about Cathodic Protection of the Ships-- ......100
17.4 Cathodic Protection of Pier Poles with Galvanic Anodes....... 100
18 Cathodic Protection of Potable Water Tanks --‚ ... 100
19 Corrosion and Corrosion Prevention in Boilers 100
19.1 Corrosion in Boilers ................ 100
19.1.1 Acidic Corrosion. 100
19.1.2 Caustic Corrosion. ... 100
19.1.3 Gas Corrosion ---‚ 100
19.1.4 Corrosion due to Boiler Water Hardness-- ---‚ 100
19.1.5 Corrosion due to Impurities in Boiler Water 100
19.2 Corrosion Prevention in Boilers ---‚ ................ 100
19.2.1 Degassing
19.2.2 Chemical Conditioning
20 Corrosion and Corrosion Prevention in Geothermal Systems
20.1 Corrosion in Geothermal Systems
20.2 Corrosion Prevention in Geothermal Systems
References
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