Corrosion control in the oil and gas industry - GBV Control in the Oil and Gas Industry Sankara...

Corrosion Control in the Oil

and Gas Industry

Sankara Papavinasam

ELSEVIER

AMSTERDAM • BOSTON • HEIDELBERG • LONDON

NEW YORK • OXFORD • PARIS • SAN DIEGO

SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO

Gulf Professional Publishing is an imprint of Elsevier

Contents

Foreword xix

Preface xxi

Acknowledgements xxv

Reviewers xxvii

CHAPTER 1 The Oil and Gas Industry 1

1.1 Introduction 1

1.2 Energy from hydrocarbons 1

1.3 What are hydrocarbons? 4

1.3.1 Alkanes (Paraffins) 4

1.3.2 Cycloalkanes (Naphthenes) 5

1.3.3 Aromatic hydrocarbons 6

1.4 Hydrocarbon sources 6

1.4.1 Conventional 7

1.4.2 Unconventional 8

1.4.3 Renewables 11

1.5 History of the oil and gas industry 13

1.6 Regulations 17

1.7 The significance and impact of corrosion in the oil and gas industry 26

1.7.1 Production sector 28

1.7.2 Transportation - pipeline sector 30

1.7.3 Transportation - other modes sector 33

1.7.4 Storage tank sector 34

1.7.5 Refinery sector 35

1.7.6 Distribution sector 35

1.7.7 Special sector 36

References 37

CHAPTER 2 Oil and Gas Industry Network 41

2.1 Introduction 41

2.2 Drill pipe 42

2.3 Casing 44

2.4 Downhole tubular 47

2.5 Acidizing pipe 55

2.6 Water generators and injectors 56

2.7 Gas generators (Teritiary recovery) 59

2.8 Open mining 61

2.9 In situ production 62

2.9.1 Cyclic steam stimulation (CSS) 62

2.9.2 Steam assisted gravity drainage (SAGD) 63

V

vi Contents

2.9.3 Toe to heel air injection (THAI) or fireflooding (In situ combustion) 63

2.9.4 Cold heavy oil production with sand (CHOPS) 65

2.9.5 Vapor extraction process (VAPEX) 65

2.10 Wellhead 65

2.11 Production pipelines 67

2.12 Heavy crude oil pipelines 70

2.13 Hydrotransport pipelines 70

2.14 Gas dehydration facilities 71

2.14.1 Oil separation 7'

2.14.2 Acid gas removal 7'

2.14.3 Water removal 72

2.15 Oil separators 72

2.15.1 Oil-gas separator 7^

2.15.2 Oil-water separator 73

2.15.3 Oil-solid separator 74

2.16 Recovery centers (Extraction plants) 74

2.17 Upgraders 75

2.18 Lease tanks 75

2.19 Waste water pipelines 76

2.20 Tailing pipelines 77

2.21 Transmission pipelines 78

2.21.1 Gas transmission pipelines 81

2.21.2 Oil transmission pipelines 82

2.22 Compressor stations 83

2.23 Pump stations 85

2.24 Pipeline accessories 87

2.25 Oil tankers 90

2.26 Liquid natural gas (LNG) transportation 91

2.27 Transportation by railcars 92

2.28 Transportation by trucks 93

2.29 Gas storage 93

2.30 Oil storage tanks 94

2.31 Refineries 97

2.31.1 Desalter unit 102

2.31.2 Atmospheric distillation unit (ADU) 102

2.31.3 Vacuum distillation unit (VDU) 105

2.31.4 Hydrotreating unit 105

2.31.5 Catalytic cracking unit (CCU) 106

2.31.6 Thermal cracking unit (TCU) 108

2.31.7 Hydrocracking unit (HCU) 108

2.31.8 Steam cracking unit (SCU) 109

2.31.9 Mercaptan oxidation unit (Merox) 109

2.31.10 Catalytic reforming unit (CRU) 109

2.31.11 Visbreaker unit 110

Contents vii

2.31.12 Coker Ill

2.31.13 Gas plants Ill

2.31.14 Alkylation unit 112

2.31.15 Isomerization unit 113

2.31.16 Gas treating unit 113

2.31.17 Water stripper 113

2.31.18 Claus sulfur plant 114

2.31.19 Heat exchangers 114

2.31.20 Cooling towers 115

2.31.21 Solvent extraction unit 116

2.31.22 Steam reforming unit 116

2.31.23 Methyl tertiary butyl ether (MTBE) unit 117

2.31.24 Polymerization unit 117

2.31.25 Hydrogen plant 117

2.31.26 Ammonia plant 117

2.31.27 Methanol plant 118

2.31.28 Other units 118

2.32 Product pipelines 118

2.33 Terminals 119

2.34 City gate and local distribution centers 120

2.35 Compressed natural gas (CNG) 120

2.36 Diluent pipelines 121

2.37 High vapor pressure pipelines 121

2.38 C02 pipelines 121

2.39 Hydrogen pipelines 122

2.40 Ammonia pipelines 123

2.41 Biofuel infrastructure 123

2.41.1 Bioethanol 124

2.41.2 Biodiesel 126

Bibliography 128

References 128

CHAPTER 3 Materials 133

3.1 Introduction 133

3.2 Properties of metals and alloys 133

3.2.1 Mechanical properties 135

3.2.2 Phase diagram 140

3.2.3 Metallography 141

3.3 Types of metals and alloys 142

3.3.1 Carbon steels 142

3.3.2 Cast irons 151

3.3.3 Alloy steels 152

3.3.4 Copper alloys 152

3.3.5 Stainless steels 155

viii Contents

3.3.6 Nickel alloys 158

3.3.7 Titanium alloys158

3.3.8 Corrosion resistant alloys '59

3.4 Classification of metals and alloys 159

3.4.1 AISI 159

3.4.2 API 160

3.4.3 ASTM 164

3.4.4 ASME 164

3.4.5 UNS 170

3.5 Non-metals 170

3.5.1 Plastics 170

3.5.2 Concrete 174

3.5.3 Cement '74

References '7^

CHAPTER 4 The Main Environmental Factors Influencing Corrosion 179

4.1 Introduction I79

4.2 Flow '79

4.2.1 Pressure drop 182

4.2.2 Flow regimes 196

4.2.3 Water accumulation 205

4.2.4 Effect of flow on corrosion 208

4.3 Oil phase 211

4.3.1 Chemical and physical constituents 211

4.3.2 Emulsion type 214

4.3.3 Wettability 215

4.3.4 Partition of chemicals between oil and water phases 216

4.4 Water (Brine or Aqueous) phase 217

4.4.1 Effect of anions 218

4.4.2 Effect of cations 219

4.4.3 The combined effect of anions and cations 219

4.5 CO; 220

4.5.1 Effect of temperature 221

4.5.2 Effect of velocity 221

4.5.3 Effect of microstructure 221

4.5.4 Effect of pH 224

4.5.5 Effect of H2S 224

4.6 H2S 224





4.6.5 Effect of C02 227

4.7 02 227


Contents ix




4.8 Sand and solids 231

4.9 Microorganisms 234

4.10 Pressure 236

4.11 Temperature 236

4.12 pH 236

4.13 Organic acids 237

4.13.1 Aliphatic acids 238

4.13.2 Naphthenic acids 238

4.14 Mercury 239

References 240

CHAPTER 5 Mechanisms 249


5.2 Electrochemical nature of corrosion 249

5.3 General corrosion 264

5.4 Galvanic corrosion 265

5.5 Pitting corrosion 265

5.6 Intergranular corrosion 267

5.7 Selective leaching (Dealloying) 269

5.8 Deposition corrosion 270

5.9 Crevice corrosion 270

5.10 Cavitation-corrosion 271

5.11 Mechanical forces 272

5.12 Fretting corrosion 274

5.13 Underdeposit corrosion 275

5.14 Microbiologically influenced corrosion 276

5.14.1 Classical mechanism 276

5.14.2 Modern mechanism 277

5.15 High temperature corrosion 279

5.15.1 Gaseous environments 279

5.15.2 Liquid (Molten) environments 281

5.16 Corrosion fatigue 282

5.17 Stress-corrosion cracking (SCC) 283

5.18 The hydrogen effect 287

5.18.1 Hydrogen blistering (HB) 288

5.18.2 Hydrogen induced cracking (H1C) 288

5.18.3 Hydrogen embrittlement (HE) 288

5.18.4 Sulfide stress cracking (SSC) 292

5.18.5 High temperature hydrogen induced cracking (HTHIC) 292

5.18.6 Hydrogen induced disbondment (HE)) 293

5.18.7 Hydrogen grooving 293

x Contents

5.19 Liquid metal cracking (LMC) or liquid metal embrittlement (LME) 293

5.20 Corrosion under protective coating and corrosion under insulation (CU1) 294

5.21 Stray current corrosion 294

5.22 Telluric current corrosion 294

5.23 Alternating current (AC) corrosion 295

5.24 Top-of-the-line corrosion (TLC) 297

Bibliography 297

References 298

CHAPTER 6 Modeling - Internal Corrosion 301


6.2 Hydrogen effects 301

6.2.1 Susceptibility of the material 302

6.2.2 Severity of the environment 304

6.3 General corrosion of carbon steel 305

6.3.1 The de Waard-Milliams models 307

6.3.2 The Srinivasan model 312

6.3.3 The Crolet model 319

6.3.4 The Nesic model 322

6.3.5 The Mishra model 323

6.3.6 The Dayalan model 323

6.3.7 The Anderko model 326

6.3.8 Oddo model 326

6.3.9 Pots model 327

6.3.10 Garber model 327

6.4 Pitting corrosion of CRAs 329

6.4.1 PREN 329

6.4.2 Laboratory evaluation 329

6.4.3 Electrochemical models 330

6.5 Localized pitting corrosion of carbon steel 334

6.5.1 The Papavinasam model 336

6.6 Erosion-corrosion 344

6.6.1 The Zhou model 345

6.6.2 The Nesic model 345

6.6.3 The Shadley model 345

6.7 Microbiologically influenced corrosion 345

6.7.1 The Checkworks model 345

6.7.2 The union electric model 346

6.7.3 The Lutey model 347

6.7.4 The Pots model : 347

6.7.5 The Maxwell model 347

6.7.6 The Sooknah model 348

6.8 Scaling 351

6.8.1 The Langelier saturation index (LSI) 351

Contents xi

6.8.2 The Ryznar stability index (RSI) 353

6.8.3 Other indices 3536.9 High-temperature corrosion 353

6.10 Top-of-the-line corrosion (TLC) 354

6.10.1 The DeWaard model 354

6.10.2 The Pots model 354

6.10.3 The Gunaltum model 355

6.10.4 The Nyborg model 355

References 355

CHAPTER 7 Mitigation - Internal Corrosion 361


7.2 Pigging 361

7.2.1 Sphere pigs 364

7.2.2 Foam pigs 365

7.2.3 Cast pigs 365

7.2.4 Mandrel pigs 366

7.2.5 Brush pigs 366

7.2.6 Plow blade pigs 368

7.2.7 Bidirectional pigs 368

7.2.8 Pin wheel pigs 368

7.2.9 Multi-diameter pigs 369

7.2.10 Bypass pigs 371

7.2.11 Gel pigs 371

7.2.12 Special pigs 373

7.3 Drying 373

7.3.1 Injection of glycol or methanol 373

7.3.2 Air drying 373

7.3.3 Vacuum drying 373

7.3.4 Purging with nitrogen 374

7.4 Corrosion inhibitors 374

7.4.1 Selection of corrosion inhibitors 378

7.4.2 Application of corrosion inhibitors 388

7.4.3 Volume of corrosion inhibitor 395

7.4.4 Inhibitor availability 397

7.4.5 Other types of inhibitors 397

7.5 Biocides 400

7.5.1 Types 400

7.5.2 Selection 402

7.5.3 Application 402

7.6 Scale inhibitors 403

7.7 Wax and asphaltene inhibitors 404

7.8 Hydrate inhibitors 405

7.9 Internal coatings and linings 406

xii Contents

7.9.1 Polymeric liners 406

7.9.2 Clad materials 418

7.9.3 Refractive liners 419

7.10 Cathodic protection 421

7.11 Process optimization 421

7.11.1 pH control 421

7.11.2 Oxygen control 422

7.11.3 Bacterial control 422

References 422

CHAPTER 8 Monitoring - Internal Corrosion 425


8.2 Laboratory measurement 425

8.2.1 Hydrogen effects 426

8.2.2 General and localized corrosion 436

8.2.3 Mechanical forces 473

8.2.4 Microbiologically influenced corrosion (MIC) 481

8.2.5 Scaling 488

8.2.6 High temperature corrosion 490

8.2.7 Crevice corrosion 491

8.2.8 Intergranular corrosion 492

8.3 Field monitoring 493

8.3.1 Mass loss 496

8.3.2 Electrical resistance (ER) probe 497

8.3.3 Polarization resistance 498

8.3.4 Electrochemical noise 499

8.3.5 Electrochemical impedance spectroscopy (EIS) 501

8.3.6 Potentiodynamic polarization 501

8.3.7 Galvanic couples 501

8.3.8 Multielectrode technique 502

8.3.9 Ultrasonic 505

8.3.10 Magnetic flux leakage (MFL) 506

8.3.11 Electromagnetic - Eddy current 507

8.3.12 Electromagnetic - remote field technique (RFT) 507

8.3.13 Radiography 508

8.3.14 Electrical field mapping (EFM) 509

8.3.15 Hydrogen probe 509

8.3.16 Corrosion potential (Ecorr) 510

8.3.17 MIC monitoring techniques 512

8.3.18 Residual corrosion inhibitors 514

8.4 Field inspection 514

8.4.1 Physical inspection 514

8.4.2 Boroscopy 515

8.4.3 Fiberscopy 516

Contents xiii

8.4.4 Liquid penetrant inspection 516

8.4.5 Magnetic particle inspection (MPI) 516

8.4.6 Thermography 516

8.4.7 Inline inspection (ILI) - magnetic flux leakage (MFL) 516

8.4.8 Inline inspection - ultrasonic (ILI-UT) 517

8.4.9 Other inline inspection tools 521

8.4.10 Reliability of corrosion data 521

References 524

CHAPTER 9 Mitigation - External Corrosion 529


9.2 Coatings 529

9.2.1 Polymeric coatings 529

9.2.2 Girth weld coatings 557

9.2.3 Repair coatings 566

9.2.4 Insulators 566

9.2.5 Metallic (thermal spray) coatings 574

9.2.6 Concrete coatings 578

9.3 Cathodic protection 582

9.3.1 Principle 583

9.3.2 Amount of current 584

9.3.3 Current source 587

9.3.4 Potential criteria 597

9.3.5 Applicability of cathodic protection 605

9.3.6 Factors influencing the effectiveness of cathodic protection 605

9.3.7 Stray currents 607

9.3.8 Side effects of cathodic protection 613

9.3.9 Materials and accessories 613

References 615

CHAPTER 10 Modeling - External Corrosion 621


10.2 Modeling corrosion control 621

10.2.1 Modes of failure of external polymeric coatings 621

10.2.2 Laboratory methodologies 625

10.2.3 Modeling using laboratory data 663

10.2.4 Modeling using field operating conditions 671

10.2.5 Modeling using above-ground surveys 680

10.2.6 Modeling using below-ground measurements 686

10.2.7 Modeling the effect ofjoint coatings 695

10.2.8 Modeling the effect of insulators 695

10.2.9 Modeling the effect of metallic coatings 696

10.2.10 Modeling the effect of concrete coatings 697

xiv Contents

10.3 Modeling corrosion 698

10.3.1 Modeling localized pitting corrosion 698

10.3.2 Modeling stress corrosion cracking 702

10.3.3 AC corrosion 711

References 7''

CHAPTER 11 Monitoring - External Corrosion 715


11.2 Holiday detection 715

11.3 Above-ground monitoring techniques 717

11.3.1 Close interval survey (CIS) 718

11.3.2 Direct current voltage gradient technique (DCVG) 720

11.3.3 Cathodic protection current requirement technique (CPCR) 721

11.3.4 Coating conductance technique (CC) 724

11.3.5 Alternating current voltage gradient technique (ACVG) 729

11.3.6 Pearson survey (PS) 730

11.3.7 Electromagnetic current attenuation (ECAT) 731

11.3.8 Transwave system technique (TS) 732

11.3.9 Electrochemical impedence spectroscopy (EIS) 733

11.3.10 Infrared camera 734

11.3.11 Cautions in using above-ground monitoring techniques 734

11.4 Remote monitoring 736

11.5 In-line inspection 736

11.5.1 Metal loss tools 741

11.5.2 Crack detection tools 741

11.5.3 Other tools 742

11.6 Hydrostatic testing 744

11.7 Below-ground inspection 744

11.7.1 Soil resistivity 744

11.7.2 Visual inspection 745

11.7.3 Moisture content 746

11.7.4 pH 746

11.7.5 Chemical analysis 746

11.7.6 Microbial analysis 747

11.7.7 Corrosion characterization 747

References 748

CHAPTER 12 Measurements 751


12.2 Types of measurement 751

12.2.1 Offline measurement 751

12.2.2 Online measurement 763

12.3 Measured properties 771

12.3.1 Physical properties of materials 771

12.3.2 Chemical properties of materials 773

Contents xv

12.3.3 Volume of oil 774

12.3.4 Volume of gas 775

12.3.5 Physical properties of oil 775

12.3.6 Physical properties of gas 780

12.3.7 Physical properties of water 780

12.3.8 Flow 781

12.3.9 Pressure 781

12.3.10 Temperature 781

12.3.11 Chemical properties of oil 782

12.3.12 Chemical properties of gas 789

12.3.13 Chemical properties of water 789

12.3.14 Sand measurement 794

12.3.15 Fouling 795

12.3.16 Soil properties 795

12.3.17 Environmental properties 796

12.4 Precautions in using measured data for corrosion control 797

References 799

CHAPTER 13 Maintenance 801


13.2 Equipment 802

13.2.1 Types of maintenance 802

13.2.2 Stages for implementation of maintenance 805

13.2.3 Activities during maintenance 808

13.2.4 Extent of maintenance 812

13.3 Workforce 812

13.3.1 Capacity 816

13.3.2 Education 816

13.3.3 Training 820

13.3.4 Experience 820

13.3.5 Knowledge 820

13.3.6 Quality 822

13.4 Data 825

13.4.1 Collection 825

13.4.2 Collection modes 828

13.4.3 Verification 828

13.4.4 Databases 829

13.4.5 Structure 829

13.4.6 Processing 830

13.4.7 Output and display 831

13.4.8 Storage 831

13.5 Communication 832

13.5.1 Self 832

13.5.2 Corrosion team 833

xvi Contents

13.5.3 Integrity team 833

13.5.4 Subordinates 833

13.5.5 Senior management834

13.5.6 Suppliers and service providers 834

13.5.7 Workers 834

13.5.8 Regulators835

13.5.9 Peers 835

13.5.10 Stakeholders 836

13.5.11 General public 836

13.5.12 Media 837

13.5.13 Lawyers and court 837

13.5.14 General 838

13.6 Associated activities 838

References 838

CHAPTER 14 Management 841


14.2 Risk assessment843

14.2.1 Occurrence ^

14.2.2 Likelihood 849

14.2.3 Consequence 8^2

14.2.4 Quantification 855

14.3 Risk management S56

14.3.1 Risk-cost relationship 856

14.3.2 Methods to estimate the cost (Economics) 859

14.3.3 Methods to optimize corrosion cost 864

14.4 Corrosion risks 883

14.5 Activities of corrosion management 883

14.5.1 Segmentation of infrastructure 891

14.5.2 Corrosion risks 892

14.5.3 Location of infrastructure 908

14.5.4 Quantification of risk 908

14.5.5 Life of infrastructure 908

14.5.6 Materials of construction 908

14.5.7 Corrosion allowance 908

14.5.8 Normal operating conditions 908

14.5.9 Upset conditions (Operating excursions) in the upstream segment 909

14.5.10 Upset conditions (Operating excursions) 909

14.5.11 Mechanisms of corrosion 909

14.5.12 Maximum corrosion rate (Internal surfaces) 909

14.5.13 Maximum corrosion rate (External surfaces) 909

14.5.14 Installation of proper accessories 909

14.5.15 Commissioning 910

14.5.16 Mitigation to control internal corrosion 910

Contents xvii

14.5.17 Mitigation strategies to control internal corrosion 910

14.5.18 Mitigated internal corrosion rate - target 910

14.5.19 Effectiveness of the internal corrosion mitigation strategy 910

14.5.20 Selection of mitigation strategies to control external corrosion 911

14.5.21 Implementation of mitigation strategies to control

external corrosion 911

14.5.22 Mitigated external corrosion rate - target 911

14.5.23 Effectiveness of external corrosion mitigation strategy 911

14.5.24 Internal corrosion monitoring techniques 911

14.5.25 Number of probes to monitor internal corrosion 911

14.5.26 Internal corrosion rates from monitoring techniques 912

14.5.27 Accuracy of internal corrosion monitoring techniques 912

14.5.28 External corrosion monitoring techniques 912

14.5.29 Number of probes to monitor external corrosion 912

14.5.30 External corrosion rate from monitoring technique 912

14.5.31 Accuracy of external corrosion monitoring techniques 912

14.5.32 Frequency of inspection 913

14.5.33 Percentage difference between internal corrosion rates from

monitoring and inspection techniques 913

14.5.34 Percentage difference between external corrosion rates from

monitoring and inspection techniques 913

14.5.35 Measurement data availability 913

14.5.36 Validity and utilization of measured data 913

14.5.37 Procedures for establishing the maintenance schedule 914

14.5.38 Maintenance activities 914

14.5.39 Internal corrosion rate after maintenance activities 914

14.5.40 Percentage difference between internal corrosion rate before

and after maintenance activities 914

14.5.41 External corrosion rate after maintenance activities 914

14.5.42 Percentage difference between external corrosion rate before

and after maintenance activity 915

14.5.43 Workforce - capacity, skills, education, and training 915

14.5.44 Workforce - experience, knowledge, and quality 915

14.5.45 Data management - Data to database 915

14.5.46 Data management - Data from database 916

14.5.47 Internal communication strategy 916

14.5.48 External communication strategy 916

14.5.49 Corrosion management review for continuous improvement 916

14.5.50 Failure frequency 917

References 917

Appendix I: Abbreviations 919

Appendix II: Unit Conversions 957

Index 961

Corrosion control in the oil and gas industry - GBV Control in the Oil and Gas Industry Sankara...

Documents

Transcript of Corrosion control in the oil and gas industry - GBV Control in the Oil and Gas Industry Sankara...