Hydrocarbon Processing and Refining: Principles and Practices

Cover
Half Title
Title Page
Copyright Page
Table of Contents
Preface
About the Author
Chapter 1 Overview of Refining and Distillation
1.1 Refining: An Overview
1.2 Distillation: A Review
1.2.1 Review of Column Internals
1.2.2 Typical Dimensions and other parameters of Internals
1.2.3 Dumping
1.3 Column Pressure Control and Reboilers
1.3.1 Pressure Control by Submergence Variation
1.3.1.1 Pressure Balance around Column Overhead, Condenser, and Reflux Drum
1.3.2 Pressure Control by Hot Vapor Bypass
1.3.3 Pressure Control with Vapor Line Restrictions
1.3.4 Case Study on Pressure Control
1.3.5 Reboilers
1.3.6 Once-Through Reboiler
1.3.7 Recirculation-Type Reboilers
1.3.8 Critical Flux
1.3.9 Problems in Reboilers
1.3.9.1 Case Study 1
1.3.9.2 Case Study 2
1.3.9.3 Case Study 3: Problem of Film Boiling in a Naphtha Vaporizer
1.3.9.4 Case Study 4: Waterfall Pool Effect in a Reboiler of a Sour Water Stripper
1.4 Processing of Heavy Crudes
1.4.1 Introduction
1.4.2 Crude Oil Upgraders
1.4.3 General Approach for Induction of Heavy Crudes
1.4.4 Processing Issues in Crude Vacuum Units
1.4.5 Design/Rating of an AVU
1.4.5.1 Rating of an Existing Unit
1.4.5.2 Considerations for New Design of a Crude–Vacuum Unit
1.4.5.3 Features Needed in Crude Units for Processing of Heavy Crudes
1.4.5.4 Features Needed in Vacuum Distillation Units for Heavy Crudes
1.4.6 Processing Issues in Coker Units for Residues Derived from Heavy Crudes
1.4.7 Processing Issues in VGO Hydrotreater/Hydrocracker Units for Feed Derived from Heavy Crudes
1.4.8 Processing Issues in FCCU for Feed Derived from Heavy Crudes
1.4.9 Effect on Other Units
1.5 Corrosion in Crude Vacuum Units with Heavy Crudes
1.5.1 Acid Corrosion
1.5.2 Caustic Injection
1.5.3 Chemistry of Caustic Reaction
1.5.4 Tramp Amines
1.5.5 Use of Filmer
1.6 Processing of High-TAN Crudes
1.6.1 Introduction
1.6.2 Methodologies Followed
1.6.3 Concerns for Use of Corrosion Inhibitors for NA
1.6.4 Mechanism of Naphthenic Acid Corrosion
1.6.5 Influence of Temperature on Naphthenic Acid Corrosion
1.6.6 Factors Influencing High-Temperature Naphthenic Acid Corrosion (Flow Velocity and Flow Regime)
1.7 Processing of Crude Oils with High Calcium
1.8 Case Studies in Distillation Units
1.8.1 Case Study 1
1.8.2 Case Study 2
1.8.3 Case Study 3
1.8.4 Case Study of Pumparound Problem of a Crude Unit
1.8.5 Case Study of a Vacuum Unit
1.8.6 Case Study of Vacuum System Bottom Coking
Bibliography
Abbreviations
Chapter 2 Fluid Catalytic Cracking Unit (FCCU)
2.1 Introduction
2.1.1 Process Description
2.2 Reactor–Regenerator Heat Balance
2.2.1 Description of R-R Section
2.2.2 Overall Heat Balance
2.2.3 Regenerator Heat Removal
2.2.4 Review of Requirement of Catalyst Cooler
2.3 Combustion Modes of Regenerators
2.4 Definition of Delta Coke
2.4.1 Types of Delta Coke
2.5 Power Recovery from Regenerator Hot Flue Gas
2.6 Operating Variables
2.6.1 Riser Temperature
2.6.2 Recycle Rate
2.6.3 Feed Preheat Temperature
2.6.4 Fresh Feed Rate
2.6.5 Catalyst Makeup Rate
2.6.6 Gasoline End Point
2.7 Fluidization and Related Equipment in FCCU
2.7.1 Fluidization
2.7.2 Typical FCCU Major Equipment/Components
2.7.3 Reactor Arrangements
2.7.4 Different Regenerator Configurations and Internals
2.8 Physical Properties of Catalysts Related to Fluidization
2.9 Guidelines for Design of Cyclones
2.9.1 Basics
2.9.2 Accepted Design Limits for Cyclones
2.10 Problems Related to Cyclones
2.10.1 High Catalyst Losses
2.10.2 Fine Generation
2.10.3 Reactor Cyclone Coking
2.10.4 Poor Catalyst Circulation
2.10.5 Poor Product Yields
2.10.6 Conclusion on Cyclones: Reasons for Failures
2.10.7 Remedies
2.11 Riser Separation System and Positive/Negative Pressure Cyclones
2.11.1 Description of Riser Separation Systems
2.12 Estimation of Transport Disengaging Height in Regenerators (source publications)
2.12.1 Estimation of Bed Level in Regenerator
2.13 Design Guidelines for Cyclone Diplegs
2.13.1 Dipleg Diameter
2.13.2 Dipleg Termination
2.14 Design and Operation Guidelines for FCC Catalyst Standpipes
2.14.1 Pressure Profiles in the FCC Standpipe
2.14.2 Catalyst Behavior and Operating Range
2.14.3 Standpipe Design Guidelines
2.14.4 Catalyst Flux
2.14.5 Standpipe Aeration Practice
2.14.6 Choice of Aeration Gas
2.14.7 Practice of Aeration in Regenerated Catalyst Standpipe (RCSP)
2.14.8 Practice of Aeration in Spent Catalyst Standpipe (SCSP)
2.15 Reactions in FCCU and Catalysts Features and Additives
2.15.1 Reaction Mechanism
2.15.2 Additives in Catalyst
2.16 Corrosion in FCCU and Its Prevention/Mitigation
2.16.1 Prevention of Ammonia Chloride Deposition
2.16.2 Calculation of NH4Cl Deposition Temperature in the Main Fractionator
2.16.3 Other Types of Salt Deposition
2.16.4 Use of Water Wash
2.16.5 Use of Polysulfides
2.16.6 Use of Corrosion Inhibitors
2.17 Simulation Guidelines
Bibliography
Abbreviations
Chapter 3 Coker
3.1 Introduction
3.2 Process Description
3.2.1 General Process Scheme
3.2.2 Feed Device
3.2.3 Wash Zone
3.3 Operating Variables
3.3.1 Coil Outlet Temperature
3.3.2 Recycle Rate
3.3.3 Drum Pressure
3.4 Activities in Decoking Operation
3.5 Effect of Feedstock
3.6 Coker Furnace and Factors Affecting Fast Furnace Fouling and frequent Decoking Operation
3.6.1 Brief Description
3.6.2 The Coil Outlet Temperature
3.6.3 Metallurgy of Tubes
3.6.4 Reasons for Rapid Fouling and Additional Coke Buildup in Furnace Tubes
3.6.4.1 Low Mass Velocity
3.6.4.2 Effect of Feed Quality on Rapid Fouling
3.6.5 Factors That Can Act As Catalyst for Rapid Fouling of Furnace
3.6.5.1 Feed Interruptions
3.6.5.2 Feed Preheating
3.6.5.3 Burners
3.6.5.4 Means to Monitor Tube Skin Temperatures
3.6.6 Gist of Actions to Improve Run Length (Suggested by Experts)
3.6.6.1 Transfer Line Configuration
3.6.6.2 Locations in a Transfer Line that can Cause Problems (According to Experts)
3.6.6.3 Ways to Fix Problems with a Problematic Transfer Line
3.6.6.4 Steam-Air Decoking
3.6.6.5 Pigging or Mechanical Coke Removal
3.6.6.6 Online Spalling
3.6.6.7 Design and Operating Parameters: Firebox
3.6.7 Decoking Operation
3.7 Coke Drum
3.7.1 Effect of Cycle Time
3.7.2 Some Salient Features in Coke Drum Design
3.7.3 Coke Drum and Drum Deformities
3.7.4 Some Key Points of the Coking Cycle and Its Effect on Coke Drums (Expert Opinion)
3.7.5 Fast Quench Issues (As Explained by Experts)
3.7.6 Gist of Findings of the Reasons for Drum Deformities (from the Experts)
3.7.6.1 Summary by Experts
3.7.7 The Coke Drum Banana Effect Syndrome
3.8 Coke Morphology and Effect on Operation
3.8.1 Factors Influencing Coke Morphology
3.8.2 Fouling in Coker
3.9 Coke Storage and Handling Safety
3.10 Case Studies
3.10.1 Case Study 1
3.10.2 Case Study 2
3.10.3 Case Study 3
3.10.4 Case Study 4
3.10.5 Case Study 5
Bibliography
Chapter 4 Hydrotreating/Hydrocracking
4.1 Introduction of the Process and Basic Functions
4.1.1 Hydrodesulfurization (HDS)
4.1.2 Hydrodenitrogenation/-denitrification (HDN)
4.1.3 Hydrodemetallization (HDM)
4.1.4 Aromatic Saturation (HDA)
4.1.5 Hydrocracking
4.2 Catalyst Functions and Mechanism of Deactivation
4.2.1 Catalyst Sulfiding
4.2.2 Deactivation of Hydroprocessing Catalyst
4.2.2.1 Coking or Fouling
4.2.2.2 Sintering
4.2.2.3 Mechanical Deactivation
4.2.2.4 Poisoning
4.2.3 Contaminants in Hydrotreater Feed
4.2.3.1 Silicon
4.2.3.2 Arsenic
4.2.3.3 Sodium and Calcium
4.2.3.4 Phosphorous
4.2.3.5 Iron
4.2.3.6 Nickel and Vanadium
4.3 Process Variables
4.3.1 Pressure
4.3.2 Temperature
4.3.3 Gas Recycle and H2/Oil Ratio
4.3.4 Space Velocity
4.4 Operating Concerns in Naphtha Hydrotreater Units
4.4.1 Increase in Pressure Drop across Reactors
4.4.2 Increase in Pressure Drop in the Reactor Effluent Circuit
4.5 Diesel Hydrotreaters and Common Operating Problems
4.5.1 Common Problems in Diesel Hydrotreaters
4.5.2 Color in Treated Diesel
4.6 Heavy Distillate Hydrotreaters and Common Operating Problems
4.6.1 Common Problems in Heavy Oil Hydrotreaters
4.6.1.1 Higher Filter Backwash Frequency
4.6.1.2 Higher Differential Pressure Drops across Reactors
4.6.1.3 Higher Differential Pressure in Reactor Effluent Circuit
4.7 Overview of Residue Hydrotreaters
4.8 Hydrocrackers and Various Configurations
4.9 Metallurgy of Hydrotreaters and Hydrocrackers
4.10 Case Studies
4.10.1 Effluent Circuit High-Pressure Drop
4.10.2 Corrosion in Diesel Hydrotreaters
4.10.3 Color in Ultra-Low High Speed Diesel (ULHSD)
4.10.4 Capacity Augmentation of a NHT
4.10.5 Capacity Augmentation of a Hydrocracker
4.10.6 Hydrotreated Wild Naphtha Processing
4.11 Improvement of Recycle Gas (RG) Purity
4.12 Essentials of Simulation
Bibliography
Abbreviations
Chapter 5 Acid Gas Treatment
5.1 Introduction
5.2 Options for Acid Gas Removal
5.2.1 Processes
5.2.2 Choice of Process
5.3 Common Physical Solvents for Acid Gas Removal
5.3.1 MeOH (Methanol)
5.3.2 DEPG (Dimethyl Ether of Polyethylene Glycol)
5.3.3 NMP (N-Methyl-2-Pyrrolidone)
5.3.4 PC (Propylene Carbonate)
5.3.5 Comparison of Physical Properties of Solvent and Gas Solubilities
5.3.6 Physical Solvent Regeneration
5.3.7 Simplified Flow scheme of few Physical solvent processes
5.4 Physical-Chemical Solvents and Processes
5.5 Chemical Solvents and Processes
5.5.1 Conventional Amine-Based Solvents Used for acid gas removal and Carbon Capture and Storage (CCS)
5.5.2 Sterically Hindered Amine Solvents
5.5.3 Non-Amine-Based Solvents
5.5.4 Chemical Reactions in the Absorber and Regenerator
5.6 Recent Trends and Advances
5.6.1 Solvent Blends
5.6.2 Chemistry of Reaction of Piperazine
5.6.3 Introduction to Ionic Liquids
5.7 Different Types of Membrane Processes
5.7.1 Spiral Wound Membrane
5.7.2 Hollow Fiber Membrane
5.7.3 One-Stage Membrane Process
5.7.4 Two-Stage Membrane Process
5.7.5 Membrane Pretreatment
5.7.6 Membrane Life
5.8 Experiences of Amine Unit in Industries
5.8.1 Effect of Amine Strength on Reboiler Condenser Duties of Amine Regenerator
5.8.2 Common Problems in Amine Units
5.8.2.1 Amine Degradation
5.8.2.2 Foaming
5.8.2.3 Corrosion
5.8.2.4 Fouling
5.8.2.5 Poor Sweet Product Quality
5.8.2.6 Carry Over of Amine to Reflux Drum of the Regenerator
5.8.3 Sources for Contamination
5.8.4 Actions to Arrest Contamination of Amine Systems
5.8.5 Actions for Lowering Contaminations
5.9 Case Studies
5.9.1 Higher Hydrocarbon Content in Acid Gas from Amine Regenerator
5.9.2 Sweet Gas Specification Not Achievable
5.9.3 Lower H2S Recovery in Tail Gas Treatment Unit Amine Absorber
5.10 Carbon Capture
Bibliography
Chapter 6 Hydrogen Generation Units
6.1 Introduction
6.2 Description of a Steam Reformer
6.2.1 Process Description
6.3 Common Process Problems
6.3.1 Sulfur Slippage to Pre-Reformer/Reformer
6.3.2 Slippage of Higher Hydrocarbons from Pre-Reformer to Tubular Reformer
6.3.3 Operation with Lower Steam-to-Carbon Ratio
6.3.4 Overheating of Tubes of Tubular Reformer
6.3.5 Quality of Steam for Reaction
6.3.6 Slippage of Chlorides
6.4 Mechanism for Deactivation of Catalysts
6.4.1 Deactivation of HDS Catalyst
6.4.2 Deactivation of Zinc Oxide (ZnO) Catalyst
6.4.3 Deactivation of Pre-Reformer Catalyst
6.4.4 Deactivation of Reformer Catalyst
6.4.5 Deactivation of Shift Catalyst
6.5 Case Studies
6.5.1 Case Study 1
6.5.2 Case Study 2
6.5.3 Case Study 3
6.6 Hydrogen Recovery
6.7 Capacity Augmentation
Bibliography
Chapter 7 Sulfur Recovery Unit
7.1 Introduction
7.2 Process Description and Reaction Mechanism
7.2.1 Claus Thermal Stage
7.2.2 Claus Catalytic Stage
7.2.2.1 Reheat Methods
7.3 Enhanced Sulfur Recovery
7.4 Common Problems in Sulfur Units
7.5 Capacity Augmentation
Bibliography
Chapter 8 Plant Safety
8.1 Introduction
8.2 Methodologies of Relief Load Computation of Columns
8.2.1 Unbalanced Heat Method (UBH Method)
8.2.2 Steady-State Simulation Method
8.2.3 Illustration/Examples for Computation by the Methods
8.2.3.1 Computation by UBH Method
8.2.3.2 Computation by Steady-State Method
8.3 Relief Load Calculation of Crude Distillation Unit
8.3.1 Top Reflux Failure
8.3.2 Pumparound Failure
8.3.3 Site Power Failure
8.4 Relief Load Calculation of Vacuum Column
8.4.1 Ejector Steam Failure
8.4.2 Cooling Water Failure
8.4.3 Pumparound Failure
8.4.4 Site Power Failure
8.5 Summary of Contingencies and Accumulation of Pressure
8.5.1 Overpressure
8.5.2 Water into Hot Oil
8.5.3 Accumulation of Pressure in Various Cases
8.6 Safety Measures in High-Pressure and Low-Pressure Interconnections
8.7 Location of Safety Valves and Special Features
8.7.1 Location of Safety Valves in High-Pressure Systems
8.7.2 Location of Safety Valves in Columns
8.7.3 Safety Valve Assembly in Refinery Columns
8.8 Relation between Design Pressure and Hydrostatic Test Pressure
Bibliography
Abbreviations
Chapter 9 Challenges in Refining
9.1 Lower Crude and Product Differential
9.1.1 Actions Required by Refiners
9.2 Stricter Product Specifications
9.2.1 Revised Specifications
9.2.1.1 Gasoline or Motor Spirit
9.2.1.2 Diesel
9.2.2 Actions Initiated by Refiners
9.2.3 Lube Oil Base Stock
9.3 Stricter Emission Norms
9.3.1 Emission Guidelines
9.3.2 Actions Necessary for Reduction of Air Emissions
9.3.3 Actions to Reduce Generation of Liquid Effluent (Recycling and Reuse)
9.3.4 Improvement in Facilities
9.4 Limited Sales of Heavy Ends and Coke
9.4.1 Actions Taken by Refiners
9.4.2 Downstream Integration with Petrochemicals
Chapter 10 Renewable Energy
10.1 Introduction
10.2 Types of Renewable Energy
10.3 Types of Biomass
10.4 Conversion of Biomass to Energy and Byproducts
10.4.1 Conversion Processes
10.5 Forms of Biofuels and Benefits of Biofuels
10.5.1 Biogas
10.5.2 Gasohol (A Blend of Gasoline and Ethanol)
10.5.3 Biodiesel
10.5.4 Benefits of Biomass Fuel
10.6 Biorefinery
10.7 Hydrogen Fuel
10.7.1 Introduction
10.7.2 Renewable Hydrogen Production Pathways
10.7.3 Relative Merits of the Technologies
10.7.4 Hydrogen Storage and Transport
10.7.5 Use of Hydrogen and Fuel Cells in Transport Sector
Bibliography
Abbreviations
Index