Petroleum Refining Volume 4

Related Resources: Design and Engineering General

Petroleum Refining Volume 4

Petroleum Refining, Materials and Equipment Volume 4

This resource requires a Premium Membership

Volume 4 in the collection "Petroleum Refining" is devoted to the main equipment found in a refinery or a petrochemical complex. As such, it is a logical sequel to the first three volumes that have already been published.

Distillation operations, which are crucial in oil refining, obviously rely mainly on separation techniques. However, they also require the use of heat transfer equipment which provides the heat energy needed for all these separations. Moreover, reaction techniques are central to all the refining processes which convert molecular species in crude oil so as to obtain products with constantly adapted and improved properties to meet market demand.

One of the features of the oil industry is that it implements liquids and gases almost exclusively. In order to carry these phases at every stage of their processing, specific equipment such as pumps, compressors, turbines and ejectors is required. In addition, a highly complex piping system makes the connections among the different pieces of equipment, in order to constitute the end products by blending and dispatch them to consumption nodes.

A refinery is thus a very complex technical facility and its profitability can be ensured only by strict and constant control of all the component parts, to guarantee product quality, operational safety and environmental protection. These aims are attained by measurement, control and supervision techniques, which are now of vital importance in all petroleum and petrochemical com- plexes.

PART ONE
Separation Technologies

Chapter 1 Gas-Liquid Contactors for Distillation:
Plate Columns
1.1 General Characteristics of a Plate 4
1.1.1 Handling Liquid and Vapor Streams 4
1.1.2 Hydraulic Behavior of a Plate. Operating Zones 7
1.2 Types of Plates or Trays 12
1.2.1 Bubble Cap Plate 13
1.2.2 Sieve Plate with Downcomer 13
1.2.3 Valve Plate 14
1.2.4 Plates without Downcomers 15
1.2.5 Comparison of Plate Technologies 17
1.3 Correlations for Plate Sizing 18
1.3.1 Flooding Due to the Gas Phase. Choosing the Column Diameter 18
1.3.2 Determining Plate Spacing 20
1.3.3 Nature of the Gas-Liquid Mixture on the Active Zone 21
1.3.4 Downcomer Cross-Section 22
1.3.5 Weirs. Downcomers 23
1.3.6 Liquid Gradient on the Plate 26
1.3.7 Vapor Pressure Drop 28
1.3.8 Entrapment 30
1.3.9 Weeping 30
1.3.10 Efficiency 31
1.4 Calculating Plate Dimensions 33
1.5 Other Parts of a Column 36
1.6 Comparison of Different Types of Plates 40
References 40

Chapter 2 Gas-Liquid Contactors for Distillation:
Packed Columns
2.1 Different Types of Packing 43
2.1.1 Random Pacldngs 44
2.1.2 Structured Packings 47
2.1.3 Grids 47
2.2 Fluid Flow in Packings 51
2.2.1 Pressure Drop 51
2.2.2 Capacity 54
2.2.3 Hold Up 58
2.2.4 Minimum Liquid Irrigation Flow Rate 59
2.3 Packing Efficiency 60
2.3.1 Estimating HETPs 62
2.3.2 Estimating HTUs 65
2.4 Phase Distribution 66
2.5 Calculating a Packed Column 72
2.5.1 Principle of the Method 72
2.5.2 Example of Sizing a Packed Column 75
2.6 Packing or Plates? 77
References 80

Chapter 3 Solvent Extraction Equipment
3.1 General Hydrodynamic Features of Liquid-Liquid Systems 81
3.2 Different Types of Extractors 84
3.2.1 Extractors without Outside Energy Contribution 85
3.2.2 Extractors with Outside Energy Contribution 92
3.3 Conclusion 102
References 103

Chapter 4 Techniques for Physical Separation of Phases
4.1 Separation of Two Fluid Phases 105
4.1.1 Gas-Liquid Separation 105
4.1.2 Liquid-Liquid Separation 112
4.2 Gas-Solid Separation 121
4.2.1 Cyclones 122
4.3 Liquid-Solid Separation 139
4.3.1 Filtration 139
4.3.2 Separation Using Centrifugal Force 148
4.4 Conclusion 155
References 155

PART TWO
Heat Transfer Technologies

Chapter 5 Process Furnaces
5.1 Furnace Functions 159
5.2 Description of a Furnace.... 160
5.3 Different Types of Furnaces 165
5.4 Furnace Thermal Efficiency 171
5.5 Component Parts of a Furnace 171
5.5.1 Tube Bundles 171
5.5.2 Tube Coil Supports 173
5.5.3 Furnace Wall Lining 174
5.5.4 Burners 175
5.5.5 Air Heater 179
5.5.6 Sweepers 183
5.6 Designing a Furnace 183
5.6.1 Determining Heat Exchange Surfaces 184
5.6.2 Fluid Dynamics in a Furnace 214
5.6.3 Mechanical Design of Structures 221
5.6.4 Control of Operating Furnaces 221
References 222

Chapter 6 Heat Exchangers Introduction 223
6.1 Heat Exchanger Functions 224
6.1.1 The Cooling Function 224
6.1.2 The Heating Function 224
6.1.3 The Condensation Function... 224
6.1.4 The Vaporization Function 225
6.2 Operating Principle 225
6.2.1 Surface Exchangers 225
6.2.2 Direct Contact Heat Exchangers (or Mixing Heat Exchangers) 226
6.3 Technological Construction Principles and Circulation Modes... 227
6.3.1 Cocurrent (or Parallel Currents) and Counter-Current Circulation 227
6.3.2 Circulation Associating Cocurrent and Counter-Current 229
6.3.3 Cross-Flow Circulation 231
6.4 Parameters Influencing Exchanger Performance 232
6.4.1 Quality of Local Transfer 233
6.4.2 Circulation Modes 253
6.5 Critical Points in Selecting Heat Exchanger Type and Technological Design 264
6.5.1 Operating Conditions 264
6.5.2 Mechanical Resistance Conditions 265
6.5.3 Maintenance Conditions 266
6.5.4 Reliability in Performance and Mechanical Resistance .. 267
6.5.5 Economic Requirements 267
6.5.6 Availability of Calculation Methods to Predict Performance 267
6.6 Shell-and-Tube Exchangers 26S
6.6.1 Types of Construction 269
6.6.2 The Shell 290
6.6.3 The Tube Bundle 290
6.6.4 Materials 302
6.6.5 Tube-Side and Shell-Side Circulation Circuits 302
6.6.6 Cost Estimation 305
6.7 Other Tubular Exchangers 305
6.7.1 Double Pipe or Coaxial Exchangers. Multi-Hairpin Exchangers 305
6.7.2 Heaters 315
6.7.3 In-Line Exchangers 319
6.7.4 Bayonet Exchangers - 319
6.7.5 Helical Wound Coil Tube Heat Exchangers 321
6.8 Compact Non-Tubular Exchangers 323
6.8.1 Plate and Frame Exchangers 324
6.8.2 Brazed Plate Exchangers 328
6.8.3 Welded Plate Exchangers 329
6.8.4 Plate-Fin Exchangers 335
6.8.5 Printed Circuit Heat Exchangers (PCHE) 343
6.8.6 Circular Plate Exchangers 345
6.8.7 Spiral Plate Exchangers 346
6.9 Air-Cooled Exchangers 349
6.9.1 The Tube Bundles 349
6.9.2 Ventilation Systems 361
6.9.3 Plenum Chambers between Fans and Bundles 364
6.9.4 Structures 366
6.9.5 Air Cooled Exchanger Layout and Installation 366
6.9.6 Special Devices 369
6.9.7 Estimating Costs 373
6.9.8 Uses - 373
6.10 Direct Contact Exchangers 375
6.10.1 Gas Coolers 375
6.10.2 Condensers 376
6.11 Conclusion 378

Appendixes 379
A6.1 Conversion Table 379
A6.2 Thermal Conductivity of Materials 380
A6.3 Characteristics of Exchanger Tubes 381
A6.4 Heat Exchanger Types 383
References • 387
XVI Contents

PART THREE
Reaction Technologies
Chapter 7 Chemical Reactor Technology
7.1 An Introduction to Reactors 391
7.1.1 Reactor Classification 392
7.1.2 Homogeneous Reactors 395
7.1.3 Reactors with Two Fluid Phases 396
7.1.4 Heterogeneous Catalytic Reactors 403
7.2 Reactors Used in Refineries 429
7.2.1 Steam Cracking 429
7.2.2 Dimerization 438
7.2.3 Gas Scrubbing by Chemical Absorption 440
7.2.4 Aliphatic Alkylation 444
7.2.5 Hydrogen Production 452
7.2.6 Catalytic Reforming 460
7.2.7 Catalytic Cracking 466
7.2.8 Hydrotreating 476
7.3 Conclusion 485
References 486

PART FOUR
Mechanical Operations
Chapter 8 Pumps, Compressors, Turbines, and Ejectors
8.1 Pumps 491
8.1.1 Centrifugal Pumps 493
8.1.2 Positive Displacement Pumps 514
8.2 Compressors 518
8.2.1 Reciprocating Piston Compressors 520
8.2.2 Centrifugal Compressors 530
8.3 Turbines 545
8.3.1 Steam Turbines 545
8.3.2 Gas Turbines 557
8.4 Ejectors 558
8.4.1 Operating Range 561
8.4.2 Sizing an Ejector 561
References 563

Chapter 9 Agitation and Mixing Techniques
9.1 The Medium 565
9.1.1 One-Phase Media: Liquid Alone 565
9.1.2 Media with Two Fluid Phases 566
9.1.3 Fluid + Solid Media 567
9.2 Agitation Systems 568
9.2.1 Different Types of Rotating Agitators 568
9.2.2 Static Mixers 571
9.3 Hydrodynamic Characteristics of the System 575
9.3.1 Hydrodynamic Regimes 575
9.3.2 Energy Dissipated by an Agitator 576
9.3.3 Mixing Time 579
9.3.4 Agitator Radius of Action 583
9.3.5 Velocity Gradient 584
9.3.6 Heat Transfer in Agitated Tanks 585
9.3.7 Mass Transfer in Agitated Tanks 587
9.4 Selecting an Agitation System 589
9.4.1 The Tank 589
9.4.2 Rotating Agitators 591
9.4.3 Other Mixing Techniques 596
9.5 Scaling-up 600
9.5.1 General Relations 600
9.5.2 Power Input 604
9.5.3 Specific Problems 604
9.6 Prospects 609
Nomenclature 609
References 611

PART FIVE
Control and Optimization Techniques

Chapter 10 Control and Monitoring
10.1 Introduction 617
10.2 Basic Principles of Industrial Measurements 617
10.2.1 Pressure 619
10.2.2 Flow Rate 621
10.2.3 Level 624
10.2.4 Temperature 626
10.2.5 Miscellaneous 627
10.3 Industrial Instrumentation Equipment 628
10.3.1 Sensors 628
10.3.2 Remote Transmission 639
10.3.3 Control Valves 643
10.3.4 Industrial Controllers 649
10.4 Analyzers 654
10.4.1 Simple Composition Analyzers 655
10.4.2 Mixture Composition Analyzers 658
10.4.3 Analyzers of Physical Characteristics 661
10.4.4 Gas Detection Analyzers 661
10.4.5 Analyzer Installation 663
10.4.6 On-line Analyzer Applications 664
10.5 Industrial Control 665
10.5.1 Level 666
10.5.2 Pressure 666
10.5.3 Flow Rate 667
10.5.4 Conclusion 667
10.6 Control Loop Design and Application 667
10.6.1 Closed Loops 667
10.6.2 Cascade Loops 668
10.6.3 Open Loops 669
10.6.4 Discontinuous Loops 670
10.6.5 Multi-Variable Loops 670
10.7 Process Automation 671
10.7.1 The Refinery and Automated Production 671
10.7.2 Automation Prerequisites 671
10.7.3 Operational Guidelines 672
10.7.4 Development Stages in an Automation Project 673
10.7.5 Control and Operating System 674
10.8 Centralized Control and Operation 676
10.8.1 Introduction 676
10.8.2 Systems and Architectures 677
10.8.3 Communications 677
10.8.4 Operating Interfaces 679
10.8.5 Processing Interfaces 680
10.8.6 Programmable Logic Controllers (PLCs) 682
10.8.7 Safety PLCs 685
10.8.8 Associated Systems 688
10.9 Refining Operations in the Future 690
References 691

Chapter 11 Rational Use of Energy
11.1 Introduction 693
11.2 Energy Accounting 693
11.3 Energy Performance 704
11.3.1 Exergy 7Q4
1 1.3.2 The Utilization Value of Energy Carriers 706
1 1.3.3 Exergy Analysis of an Industrial Process 710
11.4 Methods 713
11.4.1 Introduction 713
11.4.2 Distillation 714
11.4.3 Heat Exchangers Networks 716
11.4.4 Economic Optimization of a Heat Exchanger 731
References 734

Index 735