WHAT WENT WRONG? Case Histories of Process Plant Disasters

440 Pages·2003·15.4 MB·English

by  Trevor Kletz

F O U R T H E D I T I O N

1111, I

E

F

F O U R T H E D I T I O N

Case Histories of
Process Plant Disasters

“Most of the incidents are very simple. No
esoteric knowledge or detailed study was
required to prevent them-only
a
knowledge of what had happened before,
which this book provides.”
-Treuor Kletz

Learn from the mistakes of others. This
invaluable and respected book examines the
causes and aftermaths of numerous plant
disasters-almost
every one of which could
have been prevented. Case histories illustrate
what went wrong and why it went wrong,
and then guide you in how to circumvent
similar tragedies.

Twenty percent of the information in this
fourth edition is brand new, with fifteen new
figures and photos to help you better
recognize danger. Extensive references are a
hallmark of this trusted volume.

New sections include:
Electrical isolation
Heat radiation
Cooling coils
Recent incidents
Vacuum
relief valves
Accidents at sea
Fires
Problem sources
Emulsion breaking
Chimney effects
Interlock failure
Choosing materials.

Keep your plant running safely. No
professional concerned with operating,
maintaining, and designing process plants
should be without this classic book.

F O U R T H E D I T I O N

WHAT WENT WRONG?

F O U R T H E D I T I O N

Case Histories of
Process Plant Disasters

Trevor KIetz

Gulf Professional Publishing
an imprint of Butterworth-Heinemann

To Denise,
Who waited while I
“scorned delights and lived laborious days”
but never saw the results.

WHAT WENT WRONG?
Case Histories of Process Plant Disasters
FOURTH EDITION

Copyright 0
1999 by Elsevier. All rights reserved. Printed in the United States of
America. This book, or parts thereof, may not be reproduced in any form without
permission of the publisher.

Originally published by Gulf Publishing Company,
Houston, TX

1 0 9 8 7 6 5

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Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . , . . . I . . . xi

Preface ..........................................
xiii

Units and Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . xix

Chapter 1. Preparation for Maintenance . . . . . . . . . . . . . . .
1

1.1 Isolation, 1
1.2 Identification, 11
1.3 Removal of hazards, 16
1.4 Procedures not followed, 24
1.5 Quality of maintenance, 32
1.6 A personal note, 44

Chapter 2. Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

2.1
Startup modifications, 48
2.2
Minor modifications, 49
2.3
2.4
Temporary modifications, 56
2.5
Sanctioned modifications, 58
2.6
Process modifications, 60
2.7
New tools, 63
2.8
Organizational changes, 64
2.9
Gradual changes, 66
2.10 Modification chains, 66
2.11 Modifications made to improve the environment, 69
2.12 Control of modifications, 74

Modifications made during maintenance, 55

V

Chapter 3. Accidents Caused by Human Error . . . . . . . . . . 78

3.1
Introduction, 78
3.2
3.3
Accidents caused by simple slips, 79
Accidents that could be prevented by better training, 90

Chapter 4. Labeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

4.1
Labeling of equipment, 98
4.2
Labeling of instruments, 101
4.3
Labeling of chemicals, 104
4.4
Labels not understood. 106

Chapter 5. Storage Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

5.1
Overfilling, 108
5.2
Overpressuring, 110
5.3
Sucking in, 114
5.4
Explosions, 117
5.5
Floating-roof tanks, 125
5.6
Miscellaneous incidents, 129
5.7
FRP tanks, 133

Chapter 6. Stacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

6.1
Stack explosions, 136
6.2
Blocked stacks, 140
6.3
Heat radiation. 142

Chapter7.Leaks ..................................
144

7.1
7.2
Control of leaks, 154
7.3
7.4
Detection of leaks, 160
7.5
Fugitive emissions, 162

Some common sources of leaks, 145

Leaks onto water, wet ground, or insulation, 159

Chapter 8. Liquefied Flammable Gases . . . . . . . . . . . . . . . . 165

8.1 Major leaks, 166
8.2
Minorleaks, 174
8.3
Otherleaks, 175

vi

Chapter 9. Pipe and Vessel Failures . . . . . . . . . . .
679

9.1
Pipe failures, 179
9.2
Pressure vessel failures. 195

Ghapter IO. Other Equipment . . . . . . . . . . . . . .
= . . . . . . 205

10.1 Centrifuges, 205
10.2 Pumps, 206
10.3 Air coolers, 208
10.4 Relief valves, 209
10.5 Heat exchangers, 218
10.6 Cooling towers. 221
10.7 Furnaces, 221

Chapter 11. Entry to Vessels . . . . . . . . . . . . . . . . . . . . . .
=
a . 229

P 1.1 Vessels not freed from hazardous material, 229

P 1.2 Hazardous materials introduced, 23 1
11.3 Vessels not isolated from sources of danger, 233
1 1.4 Unauthorized entry, 236
11.5 Entry into vessels with irrespirable atmospheres. 238
11.6 Rescue, 239
1 I .7 Analysis of vessel atmosphere, 241
1 1.8 What is a confined space?, 241
1 I .9 Every possible error, 242

Chapter 12. Hazards of Common Materials . . . .
a . . . . . 244

12.1 Compressed air, 244
12.2 Water, 246
12.3 Nitrogen, 248
12.4 Heavy oils (including heat transfer oils), 255

Chapter 13. Tank Trucks and Cars . . . . . . . . . . . . . . . . . . 262

13.1 Overfilling, 262
13.2 Burst hoses, 263
13.3 Fires and explosions, 265
13.4 Liquefied flammable gases, 266
13.5 Compressed air, 266
13.6 Tipping up, 267
13.7 Emptying into or filling from the wrong place, 268
13.8 Contact with live power lines, 270

vii

Chapter 14. Testing of Trips and Other Protective
Systems ...............................
272

14.1 Testing should be thorough, 272
14.2 All protective equipment should be tested, 275
14.3 Testing can be overdone, 279
14.4 Protective systems should not reset themselves, 279
14.5 Trips should not be disarmed without authorization, 281
14.6 Instruments should measure directly what we need
to know, 284
14.7 Trips are for emergencies, not for routine use, 285
14.8 Tests may find faults, 286
14.9 Some miscellaneous incidents, 286
14.10Some accidents at sea, 287

Chapter 15. Static Electricity . . . . . . . . . . . . . . . . . . .

15.1 Static electricity from flowing liquids, 291
15.2 Static electricity from gas and water jets, 293
15.3 Static electricity from powders and plastics, 294
15.4 Static electricity from clothing, 296

Chapter 16. Materials of Construction . . . . . . . . . . . ,

16.1 Wrong material used, 299
16.2 Hydrogen produced by corrosion, 303
16.3 Other effects of corrosion, 305
16.4 Loss of protective coatings, 305
16.5 Some other incidents caused by corrosion, 306
16.6 Fires, 306
16.7 Choosing materials, 307

I . . ,

. . . 290

. .. 299

Chapter 17. Operating Methods . . . . . . . . . . , . . . . . . . . . . . 309

17.1 Trapped pressure, 309
17.2 Clearing choked lines, 3 11
17.3 Faulty valve positioning, 313
17.4 Responsibilities not defined, 314
17.5 Communication failures, 3 15
17.6 Work at open manholes, 318
17.7 One line, two duties, 318
17.8 Inadvertent isolation, 319
17.9 Incompatible storage, 319

viii

17.10.Maintenance-is it really necessary?, 320
17.11 An interlock failure, 32 1
17.12 Emulsion breaking, 322
17.13Chimney effects, 323

Chapter 18. Reverse Flow and Other Unforeseen
Deviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327

18.1 Reverse flow from a product receiver or blowdown line back
into the plant, 327
18.2 Reverse flow into service mains, 329
18.3 Reverse flow through pumps, 331
18.4 Reverse flow from reactors, 331
18.5 Reverse flow from drains, 333
18.6 Other deviations, 334
18.7 A method for foreseeing deviations, 335
18.8 Some pitfalls in hazop, 337
18.9 Hazop of batch plants, 338
18.10Hazop of tank trucks, 340

Chapter 19. I Didn’t Know That. . . . . . . . . . . . . . . . . . . . . . . 343

19.1 Ammonia can explode, 343
19.2 Hydraulic pressure tests can be hazardous, 345
19.3 Diesel engines can ignite leaks, 346
19.4 Carbon dioxide can ignite a flammable mixture, 348
19.5 Mists can explode, 348
19.6 The source of the problem lay elsewhere, 350

Chapter 20. Problems with Computer Control . . . . . . . . . . 353

20.1 Hardware and software faults, 353
20.2 Treating the computer as a black box, 354
20.3 Misjudging the way operators will respond, 359
20.4 Other problems, 360
20.5 Unauthorized interference, 362
20.6 New applications, 363
20.7 Conclusions, 365

IX

Chapter 21. Inherently Safer Design . . , . . . . . . . . . . . . . . . 367

21.1 Bhopal, 368
2 1.2 Other examples of inherently safer design. 372
2 1.3 User-friendly design, 377

Chapter 22. Reactions-Planned and Unplanned . . . . . . . . 380

22.1 Lack of knowledge, 381
22.2 Poor mixing, 383
22.3 Contamination, 385
22.4 Reactions with auxiliary materials. 387
22.5 Poor training or procedures, 387
22.6 Use-by dates, 388

Appendix 1. Relative Frequencies of Incidents . . . . . . . . . . 392

Appendix 2. Final Thoughts . . . . . . . . . . . . . . . . . . . . . . . . . 395

Appendix 3. Recommended Reading . . . . . . . . . . . . . . . . . 397

Index ............................................
399

X

Acknowledaments

Thanks are due to the staffs of the companies where the incidents
occurred for allowing me to describe their mistakes; to many colleagues,
past and present, especially to Professor E P. Lees for his ideas and
advice; and to the UK Science and Engineering Research Council and
the Leverhulme Trust for their financial support.

xi