Preface xix
Acknowledgments xxi
Part I Market, Design and Technology Overview 1
1 Overview of This Book 3
1.1 Why Petrochemical Products are Important for the Economy 3
1.2 Overall Petrochemical Configurations 8
1.3 Context of Process Designs and Operation for Petrochemical Production 11
1.4 Who is This Book Written For? 11
2 Market and Technology Overview 13
2.1 Overview of Aromatic Petrochemicals 13
2.2 Introduction and Market Information 13
2.3 Technologies in Aromatics Synthesis 21
2.4 Alternative Feeds for Aromatics 27
2.5 Technologies in Aromatic Transformation 28
2.6 Technologies in Aromatic Separations 35
2.7 Separations by Molecular Weight 39
2.8 Separations by Isomer Type:paraXylene 39
2.9 Separations by Isomer Type:metaXylene 44
2.10 Separations by Isomer Type:orthoXylene and Ethylbenzene 45
2.11 Other Related Aromatics Technologies 46
2.12 Integrated Refining and Petrochemicals 57
References 61
3 Aromatics Process Description 63
3.1 Overall Aromatics Flow Scheme 63
3.2 Adsorptive Separations forparaXylene 64
3.3 Technologies for Treating Feeds for Aromatics Production 68
3.4paraXylene Purification and Recovery by Crystallization 68
3.5 Transalkylation Processes 71
3.6 Xylene Isomerization 72
3.7 Adsorptive Separation of PuremetaXylene 76
3.8paraSelective Catalytic Technologies forparaXylene 78
References 81
Part II Process Design 83
4 Aromatics Process Unit Design 85
4.1 Introduction 85
4.2 Aromatics Fractionation 85
4.3 Aromatics Extraction 88
4.4 Transalkylation 96
4.5 Xylene Isomerization 101
4.6paraXylene Separation 105
4.7 Process Design Considerations: Design Margin Philosophy 106
4.8 Process Design Considerations: Operational Flexibility 108
4.9 Process Design Considerations: Fractionation Optimization 109
4.10 Safety Considerations 110
4.10.1 Reducing Exposure to Hazardous Materials 110
4.10.2 Process Hazard Analysis (PHA) 110
4.10.3 Hazard and Operability (HAZOP) Study 110
Further Reading 111
5 Aromatics Process Revamp Design 113
5.1 Introduction 113
5.2 Stages of Revamp Assessment and Types of Revamp Studies 113
5.3 Revamp Project Approach 115
5.4 Revamp Study Methodology and Strategies 116
5.5 Setting the Design Basis for Revamp Projects 118
5.6 Process Design for Revamp Projects 121
5.7 Revamp Impact on Utilities 123
5.8 Equipment Evaluation for Revamps 124
5.9 Economic Evaluation 147
5.10 Example Revamp Cases 152
Further Reading 154
Part III Process Equipment Assessment 155
6 Distillation Column Assessment 157
6.1 Introduction 157
6.2 Define a Base Case 157
6.3 Calculations for Missing and Incomplete Data 159
6.4 Building Process Simulation 161
6.5 Heat and Material Balance Assessment 162
6.6 Tower Efficiency Assessment 164
6.7 Operating Profile Assessment 166
6.8 Tower Rating Assessment 168
6.9 Guidelines for Existing Columns 169
Nomenclature 170
Greek Letters 170
References 170
7 Heat Exchanger Assessment 171
7.1 Introduction 171
7.2 Basic Calculations 171
7.3 Understand Performance Criterion: UValues 173
7.4 Understand Fouling 176
7.5 Understand Pressure Drop 178
7.6 Effects of Velocity on Heat Transfer, Pressure Drop, and Fouling 178
7.7 Improving Heat Exchanger Performance 185
7.A TEMA Types of Heat Exchangers 186
References 188
8 Fired Heater Assessment 189
8.1 Introduction 189
8.2 Fired Heater Design for High Reliability 189
8.3 Fired Heater Operation for High Reliability 194
8.4 Efficient Fired Heater Operation 197
8.5 Fired Heater Revamp 201
References 202
9 Compressor Assessment 203
9.1 Introduction 203
9.2 Types of Compressors 203
9.3 Impeller Configurations 205
9.4 Type of Blades 207
9.5 How a Compressor Works 207
9.6 Fundamentals of Centrifugal Compressors 208
9.7 Performance Curves 209
9.8 Partial Load Control 210
9.9 Inlet Throttle Valve 212
9.10 Process Context for a Centrifugal Compressor 212
9.11 Compressor Selection 213
References 213
10 Pump Assessment 215
10.1 Introduction 215
10.2 Understanding Pump Head 215
10.3 Define Pump Head: Bernoulli Equation 216
10.4 Calculate Pump Head 218
10.5 Total Head Calculation Examples 219
10.6 Pump System Characteristics: System Curve 221
10.7 Pump Characteristics: Pump Curve 222
10.8 Best Efficiency Point (BEP) 224
10.9 Pump Curves for Different Pump Arrangement 225
10.10 NPSH 226
10.11 Spillback 229
10.12 Reliability Operating Envelope (ROE) 230
10.13 Pump Control 230
10.14 Pump Selection and Sizing 231
Nomenclature 233
Greek Letters 233
References 233
Part IV Energy and Process Integration 235
11 Process Integration for Higher Efficiency and Low Cost 237
11.1 Introduction 237
11.2 Definition of Process Integration 237
11.3 Composite Curves and Heat Integration 238
11.4 Grand Composite Curves (GCC) 244
11.5 Appropriate Placement Principle for Process Changes 244
11.6 Systematic Approach for Process Integration 249
11.7 Applications of the Process Integration Methodology 251
References 261
12 Energy Benchmarking 263
12.1 Introduction 263
12.2 Definition of Energy Intensity for a Process 263
12.3 The Concept of Fuel Equivalent (FE) for Steam and Power 264
12.4 Calculate Energy Intensity for a Process 265
12.5 Fuel Equivalent for Steam and Power 267
12.6 Energy Performance Index (EPI) Method for Energy Benchmarking 271
12.7 Concluding Remarks 272
References 273
13 Key Indicators and Targets 275
13.1 Introduction 275
13.2 Key Indicators Represent Operation Opportunities 275
13.3 Defining Key Indicators 277
13.4 Set Up Targets for Key Indicators 280
13.5 Economic Evaluation for Key Indicators 283
13.6 Application 1: Implementing Key Indicators into an Energy Dashboard 285
13.7 Application 2: Implementing Key Indicators to Controllers 287
13.8 It is Worth the Effort 287
References 288
14 Distillation System Optimization 289
14.1 Introduction 289
14.2 Tower Optimization Basics 289
14.3 Energy Optimization for Distillation System 293
14.4 Overall Process Optimization 296
14.5 Concluding Remarks 302
References 302
15 Fractionation and Separation Theory and Practices 303
15.1 Introduction 303
15.2 Separation Technology Overview 303
15.3 Distillation Basics 305
15.4 Advanced Distillation Topics 311
15.5 Adsorption 316
15.6 Simulated Moving Bed (SMB) 317
15.7 Crystallization 320
15.8 LiquidLiquid Extraction 320
15.9 Extractive Distillation 321
15.10 Membranes 322
15.11 Selecting a Separation Method 323
References 324
16 Reaction Engineering Overview 325
16.1 Introduction 325
16.2 Reaction Basics 325
16.3 Reaction Kinetic Modeling Basics 326
16.4 Rate Equation Based on Surface Kinetics 328
16.5 Limitations in Catalytic Reaction 330
16.6 Reactor Types 333
16.7 Reactor Design 335
16.8 Hybrid Reaction and Separation 340
16.9 Catalyst Deactivation Root Causes and Modeling 341
References 343
Part V Operational Guidelines and Troubleshooting 345
17 Common Operating Issues 347
17.1 Introduction 347
17.2 Startup Considerations 348
17.3 Methyl Group and Phenyl Ring Losses 349
17.4 Limiting Aromatics Losses 350
17.5 Fouling 356
17.6 Aromatics Extraction Unit Solvent Degradation 360
17.7 Selective Adsorption ofparaXylene by Simulated Moving Bed 363
17.8 Common Issues with Sampling and Laboratory Analysis 371
17.9 Measures of Operating Efficiency in Aromatics Complex Process Units 374
17.10 The Future of Plant Troubleshooting and Optimization 377
References 377
18 Troubleshooting Case Studies 379
18.1 Introduction 379
18.2 Transalkylation Unit: Low Catalyst Activity During Normal Operation 379
18.3 Xylene Isomerization Unit: Low Catalyst Activity Following Startup 381
18.4paraXylene Selective Adsorption Unit: Low Recovery After Turnaround 384
18.5 Aromatics Extraction Unit: Low Extract Purity/Recovery 385
18.6 Aromatics Complex: LowparaXylene Production 386
18.7 Closing Remarks 388
Reference 389
Index 391
