Distillation Diagnostics - Henry Z Kister

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Résumé :

Thorough guide on how to use various diagnostic techniques to troubleshoot problems in distillation columns

Distillation Diagnostics familiarizes the reader with the multitude of tools available for diagnosing distillation and absorption tower problems and provides the reader with application guidelines derived from 40+ years of real-world experiences of the author.

The book describes the capabilities, strengths and limitations of each tool, provides guidance on how to apply these tools to get the most insight and to test theories and ideas, shares the experience of how to correctly interpret the results provided by each technique, and guides the reader to a multitude of additional testing that they can perform to bring them closer to a correct diagnosis and an effective fix. Each technique is illustrated with real case studies and an extensive dos and don'ts list.

Written by a global authority on distillation diagnostics and troubleshooting known as 'The Tower Doctor' by many in the field, Distillation Diagnostics includes information on:

• Possible solutions to the growing distillation failure rate despite the tremendous recent advances in distillation technologies
• Time-tested tools and techniques for correctly diagnosing distillation problems to provide simple low-cost fixes instead of unnecessary wasteful solutions, thus eliminating waste and dramatically reducing CAPEX, energy consumption and carbon footprint
• Combining the various diagnostic techniques to discard wrong theories and narrow in on the correct root cause and proper solution for various tower malfunctions
• Diagnosing flooding, foaming, plugging, weeping, maldistribution, channeling, distributor and collector overflows, low efficiencies, feeds and draws bottlenecks, assembly mishaps, tower internals damage, high base level issues, reactions in towers, contaminants, internal and external leaks, startup and/or shutdown difficulties
• Correctly interpreting gamma scan, thermal scan, and pressure drop data
• Getting the most out of testing techniques such as gamma scanning, neutron backscatter, wall temperature surveys, pressure drop measurements, column testing, sketching points of transition, collecting data for simulations, conducting mass and energy balances, analyzing operating charts, and in-situ water testing
• Turnaround tower inspections: what to look for
• Advanced gamma scanning and thermal scanning techniques and when to apply
• The doctor and patient troubleshooting strategy, which often constitutes the most effective, most systematic, and least expensive course of action
• Things to remember when formulating and testing theories, such as the balance between theory, data, the laws of physics, and chemistry

Distillation Diagnostics is a timely, essential reference on the subject for plant managers and operators, production and startup supervisors, and chemical, process, and design engineers....

Biographie:

Henry Z. Kister is a Fluor Corporation senior fellow and director of fractionation technology. He has over 40 years expertise in all phases of distillation, including troubleshooting, operation, debottlenecking, design, start-up, and control of fractionation processes and equipment. For over 30 years, Mr. Kister has led the IChemE-sponsored 3-day continuing education course Practical Distillation Technology, by now presented over 550 times in public and for major corporations in 26 countries on all 6 continents....

Sommaire:

Preface xv

List of Acronyms xix

Acknowledgments xxi

1. Troubleshooting Steps 1

1.1 Causes of Column Malfunctions 2

1.2 Column Troubleshooting - a Case History 4

1.3 Strategy for Troubleshooting Distillation Problems 6

1.4 Dos and Don'ts for Formulating and Testing Theories 12

1.5 Learning to Troubleshoot 17

1.6 Classification of Column Problems 18

2. Troubleshooting for Flood 21

2.1 Flooding: The Most Common Tower Throughput Limitation 21

2.2 Flood Mechanisms in Tray and Packed Towers 22

2.3 Flood and Flood Mechanism Determination: Hydraulic Analysis 25

2.4 Operating Window (or Stability) Diagrams 27

2.5 Flood Point Determination: Field Testing 29

2.6 Flood Point Determination in The Field: The Symptoms 31

2.7 Flood Mechanism Determination: Vapor and Liquid Sensitivity Tests 43

2.7.1 Extension of Vapor/Liquid Sensitivity Tests to Complex Fractionators 44

2.8 Gaining Insight into The Cause of Flood From dP Versus Vapor Rate Plots 46

2.9 Diagnosing Floods that Give Small dP or No dP Rise 51

2.9.1 Flood Diagnosis in a Chemical Vacuum Tower with no dP Rise 53

2.9.2 Flood Diagnosis in Packed Pumparound (PA) Beds 54

2.10 Foam Flooding Symptoms and Testing 55

2.11 Downcomer Unsealing Floods at Low Liquid Loads 64

2.12 Channeling-Induced Premature Floods at High Liquid Loads 66

2.13 Floods by High Base Level or Entrainment From the Tower Base 67

2.14 Troubleshooting Intermediate Component Accumulation 71

2.15 Troubleshooting Liquid Side Draw Bottlenecks 74

2.16 Twelve Useful Rules of Thumb 77

3. Efficiency Testing and Separation Troubleshooting 81

3.1 Efficiency Testing for Troubleshooting 81

3.1.1 Purpose and Strategy of Efficiency Testing for Troubleshooting 81

3.1.2 Planning and Execution of Efficiency Testing for Troubleshooting 83

3.1.3 Preparations for Efficiency Testing 85

3.1.4 Last-Minute Preparations 97

3.1.5 The Test Day(s) 100

3.1.6 Processing the Results 100

3.1.7 Determining Hydraulic Loads 113

3.1.8 Hennigan's Rules 115

3.2 Diagnosing Poor Separation 116

3.2.1 Troubleshoot for Process Leaks 116

3.2.2 Troubleshoot for Tray Weeping 120

3.2.3 Diagnosing Side Draw Liquid Starvation 122

3.2.4 Diagnosing Once-Through Reboiler Liquid Starvation 124

3.2.5 Troubleshoot for Liquid in Vapor Side Draws 125

3.2.6 Troubleshoot for Missing or Damaged Trays or Packing 125

3.2.7 Poor Material Balance Control Produces High Impurities 127

3.2.8 Limitations on Reflux or Reboil Generation 128

3.2.9 Control Instability Increases Impurities 129

3.2.10 Impurities and Contaminants Affecting Azeotroping and Product Purities 129

3.2.11 Absorption of Sparingly Soluble Gases Affecting Product Purity and Downstream Venting 130

3.2.12 Reactions and Contaminants Can Affect Product Purity 130

4. Diagnosing Packed Tower Maldistribution 135

4.1 Diagnosing Packing Maldistribution: an Overview 135

4.2 Expected Packing HETPS 137

4.3 Small-Scale Versus Large-Scale Maldistribution: Do They Equally Raise Hetp? 137

4.4 By How Much does Maldistribution Reduce Packing Efficiency? 138

4.5 Diagnosing Packing and Distributor Plugging 141

4.6 Troubleshooting for Distributor, Collector, and Parting Box Overflows 145

4.6.1 Overflows and Their Impact 145

4.6.2 Overflows in Distributors, Redistributors, and Parting Boxes 145

4.6.3 Overflows in Collectors 148

4.6.4 Overflows due to Plugging, Foaming, Impingement ...