Corrosion in Petroleum Refineries

Overview of role of corrosion control and its management in petroleum refineries.

- What corrosion control & Its Management requires:

* Understanding Processes

* Understanding Materials

* Understanding Damage Mechanisms

- How to control corrosion & manage the integrity of equipment for smooth operation avoiding catastrophes / failures , requires:

* Master list of equipment

* Criticality of equipment based on risk

> Where to monitor (CMLs)

> What to monitor ( Skill of Damage Mechanism)

> How to monitor (Skill of Inspection & NDT both Intrusive & Non intrusive ) 

> When to monitor  (RBI inspection Plans : Frequency of inspection-On stream/ Off stream )

> How to mitigate (Decision for Repair / Replacement)

> How to control ( Developing & Implementing Integrity Operating Window)

- What's the difference in Corrosion Prevention & Corrosion Control?

- Why shutdown & turn around are mandatory for enhancing the life & integrity of equipment?

- History of Petroleum Refineries

- Processing Units in refineries

* Primary Units

* Secondary Units

* Auxiliary Units

- Schematic flow diagram of Modern Petroleum refinery.

- Refinery & Its end Products

- Practical Fundamentals of Corrosion & Material Science

- Importance of Feed / Design & Construction stage RBI

- Importance of IOW & Turnaround & Culture of Company

- Factors Affecting Corrosion & Metallurgical Degradation

- Why Corrosion Experts are mandatory in refinery?

- Importance of periodic table in understanding the corrosion from the root of its origin.

- How Scale causes the corrosion & prevent the corrosion.

- Role of oxygen & chloride in corrosion control.

- Type of Corrosion

- Corrosion : A Redox reaction. 

Fundamental of Corrosion Science & Engineering

- Pitting Corrosion Mechanism in Offshore Environment.

- MIC Corrosion

- Corrosion Drivers : Oxidizing agents Vs. Stimulating factors

- Water Corrosion in Carbon Steel.

- Why Catastrophes Occur due to poor design based on Corrosion Allowance?

- Principle behind protection from corrosion.

- Cathodic Protection : Sacrificial anode & Impressed Current Methods

- High  Temperature Corrosion Mechanisms:

* High Temperature Oxidation

* Sulfidation 

* HTHA

* NAC

* Carburization

* Fuel Ash Corrosion

* LME

- Forms of Corrosion

* Uniform Corrosion

* Localized Corrosion

# Galvanic  Corrosion

# Crevice Corrosion

# Pitting Corrosion

# Erosion / Corrosion , Fretting Corrosion, Cavitation

# Dealloying

# Intergranular Corrosion

# Stress Corrosion Cracking

# Corrosion Fatigue

- Monitoring Corrosion rate  by coupon methods

- Alternating Field Current Magnetic Test (ACFM)

- Why Tacit skill & RCA for Corrosion Control & its Management ?

- Known Damage Mechanisms in in-service assets.

- Short Over view of Corrosion & Metallurgical Degradation  Mechanisms.

-Secret of Corrosion: Oxygen Causes the corrosion & Chlorides expedite the corrosion.

-  Oxygen is most corrosive element in periodic table , why?

- Sweet Corrosion Damage Mechanism.

- Alkaline Stress Corrosion Cracking (ASCC)

- Caustic Gouging & Caustic Embrittlement

- Caustic Service Chart   for selection of material.

- Factors Affecting Corrosion Rate

- Review of Basic Damage Mechanisms in Refineries

* Micro-biologically influenced corrosion (MIC)

* Atmospheric Corrosion

* CUI / CUF

# Design factors causing CUI

# Susceptible locations for CUI

# CUI in Carbon Steel / Stainless Steel

# CUI monitoring

. Thermography

. Neutron Back Scattered Technique

. Guided Wave Examination  methods / Long Range Ultrasonic Test (LRUT)

. Real Time Tangential RT

. Profile Radiography

. Pulse Eddy Current testing

. Case study: Pulse eddy current along with close visual inspection with callipers.

- Corrosion under fire proofing

Over view of Damage Mechanisms in Petroleum Refineries

- Localized Corrosion in austenitic stainless steels.

- How integrity of austenitic stainless steels lies in the preservation of passive protective surface film otherwise it corrode even faster than carbon steel?

- Susceptibility of austenitic stainless steels to multiple type of corrosion mechanism:

* Fatigue & Corrosion Fatigue

* Chloride Stress Corrosion Cracking (Trans-granular Cracking)

* Polythionic Acid Stress Corrosion Cracking (PTASCC)

* Hydrogen Embrittlement (HE)

* Hydrogen Induced Cracking (HIC)

* Sulphide Stress Corrosion Cracking (SSCC)

* Crevice Corrosion (Pitting / CSCC)

* Liquid Metal Embrittlement (LME): Molten Zinc over ASS in stressed condition

- Localized Corrosion in carbon steel / Low alloy steels

* Sour Water Corrosion & Cracking

.Hydrogen Embrittlement

. HIC/ SOHIC / SWC/ SSC

. HTHA

. General Corrosion with deposit

. General Corrosion without deposit

* Localized Under Deposit Corrosion

- Cooling Water Corrosion

* Fouling & Cooling Water Corrosion

* Impact of Temperature on Cooling Water Corrosion

* Type of Industrial Cooling Water & Corrosion

* Microbiologically Influenced Corrosion (MIC) in Cooling water

* Impact of Fluid Velocity on Cooling Water Corrosion

* Impact of Hardness on Cooling Water Corrosion

* Why CW Corrosion accelerated  on Low elevation, Dead Leg /Dead Ends & High elevation ?

*   Why Cooling water coolers , cooling water is preferred tube side?

* Cooling water Corrosion & Metallurgy Selection of Tube Bundle.

- Flow Accelerated Corrosion (FAC)

- Causes of FAC & Its Control.

- Sulfidation Corrosion / Sulfidic Corrosion ( Dry Corrosion )

* High Temperature Sulfidation Corrosion (T > 260 deg. C)

* Sulfidation : High temperature Erosion Corrosion (Flow rate & Flow type)

* High Temperature Sulfidation without Hydrogen

* High Temperature Sulfidation with Hydrogen : Why More Severe

* High Temperature Sulfidation Corrosion & MCconomy Curves

- Sour Water H2S Corrosion & SCC (Wet Corrosion)

* Sour Corrosion in High Pressure  Pipelines

* Sour Corrosion in Low pressure piping & equipment

Over View  of Corrosion Damage Mechanisms in Petroleum Refineries

- Review of sour water corrosion & Cracking

- Q & A on sour water Corrosion & cracking

- Morphologies of damage mechanisms in sour service : HIC/SWC, Blistering, SOHIC, SSC

- How HIC gets converted to SWC?

- Hydrogen Embrittlement.

- Are Cracks born from Pits in sour service?

- Damage Mechanism : ClSCC in Austenitic stainless / Duplex Stainless Steels.

- ClSCC : Q & A

- What's Sulfide Stress Cracking in Sour Service?

- Why HIC (Blistering ) possible at much lower concentration of H2S than sulfide pitting?

- ISO15156 Classification : Severity zone of Sour Corrosion based on pH & Partial pressure of H2S.

- Sour Water Corrosion & Cracking Mechanism

- Sulfide Stress Cracking (SSC) Mechanism.

- HIC resistant Material Specification

- Hydrogen Embrittlement

- Hydrogen Bake out for repair of equipment in sour service.

- Impact of Hydrogen Embrittlement

- HIC VS. HTHA

- Hydrogen Embrittlement in concrete structure due to prestressed high strength steels.

- Sour Corrosion & Cracking : Q & A 

- CO2 Corrosion

- High Temperature Hydrogen Attack (HTHA)

* Four Stages of HTHA Damages.

* Why advanced stage HTHA damages difficult to monitor and control proactively.

* Factors Affecting HTHA

- Ammonium Bisulfide Corrosion (ABS)

* ABS is Alkaline Sour Water Corrosion

* Bell Curve & Ammonium Bisulfide Corrosion

* Environmental factors causing ammonium bisulfide corrosion.

* Units Affected in refinery by ammonium bisulfide corrosion.

* Mechanism of ammonium bisulfide corrosion.

* Selection of material for ammonium bisulfide corrosion

- HCl corrosion in CDU overhead system.

Corrosion & Metallurgical Degradation Damage Mechanisms Review

- Hydrogen Fluoric Acid (HF) Corrosion : Causes both thinning & Cracking

* Factors Affecting Hydrogen Fluoric Acid Corrosion & Cracking

* CS Corrosion by Hydrofluoric Acid.

* Case Study : Catastrophic Failure of CS elbow by  Hydrogen Fluoric acid  in Alkylation Unit of Philadelphia Refinery

* Selection of material for HF service in different range of temperature.

* Cost of ignoring Corrosion in HF service.

- Ammonium Chloride (NH4Cl) Corrosion

* Mechanism of Ammonium Chloride Corrosion.

* Mechanism of Amine Neutralizer with HCl forming Corrosive Amine Salt.

* Material Resistant to Ammonium Chloride Corrosion.

* Why 300 Austenitic Stainless Steels are not Reliable for NH4Cl service?

- Naphthenic Acid Corrosion

* Naphthenic acid & Polythionic acid

* Type of Naphthenic Acid and their relative impact on the severity of corrosion.

* High Temperature Naphthenic Acid Corrosion : Susceptible Units, Equipment & Corrosion Monitoring Locations.

* Materials Resistant to Naphthenic Acid Corrosion.

* Factors Affecting NAC.

* Why TAN is misleading in predicting the severity of NAC corrosion.?

* Why high Sulphur Crude has more resistance to Naphthenic Acid Corrosion?

* Why low Sulphur Crude are more prone to Naphthenic Acid Corrosion ?

* Why Naphthenic Acid Crudes are not corrosive beyond 400 deg. C.?

* Why Naphthenic Acid Crude are not corrosive in presence of catalyst?

- Ethanol Stress Corrosion Cracking (ESCC)

* Factors Affecting Ethanol Stress Cracking (ESCC)

- Oxidation Damage Mechanisms

* Oxidation Damage Mechanism at low temperature in wet condition

* Oxidation Damage Mechanism at High Temperature Dry Condition.

- Flue Gas Dew Point Corrosion

* Difference in Oxidation & Sulfidation in Ni-Cr-Fe Alloys.

* Role of Aluminium addition in Ni-Cr-Fe alloys in Flue Gas Exposure at Elevated Temperature in sulfurous environment..

*   Q & A : What's the role of Aluminium alloying in Ni-Cr-Fe Alloys.?

- Dissimilar Metal Weld (DMW ) Cracking

* Why DMW joint crack in HAZ of ferrite side base metal?

* DMW Cracking Prevention & Mitigation

* Appearance & Morphology of DMW Cracking

- Stress Relaxation Cracking (SRC) : Cracking due to change of metastable phases to stable phases by reheating/ service

* SRC during Fabrication : 

. Reheat Cracking

. Stress Relief Cracking

. Repair Welding

* SRC in in-service

. Creep Embrittlement

. Stress Induced Cracking

. Stress Assisted Grain Boundary Oxidation Stress Cracking (SAGBO)

* What's the Driving Force for SRC?

* SAGBO in Hydrogen Reformer Outlet Pigtail Piping.

* Why SRC Fracture  is Intergranular?

- Reheat Cracking (Part of SRC)

* Factors Affecting Reheat Cracking

* Characteristics of Reheat Cracking .

* Affected Units ? Equipment by Reheat Cracking

- Sigma Phase / Chi Phase / Alpha Prime Embrittlement ( Type of SRC)

- Creep Degradation Mechanisms

*  Softening ( Spheroidization ) in Ferritic/ Pearlitic Steels

* Creep Voids Formation & Micro ? Macro Cracking.

* Formation of Precipitates in Tempering Heat Treatment : Diffusion Controlled Transformation

* ISPESL Classification of Creep Damages

* Effect of Loading (throughput) on creep .

* Creep Damage Mechanism of Reformer Tubes

* 3 Stages of Creep Crack Propagation in Reformer Tubes . 

Over View of Corrosion & Metallurgical Degradation Damage Mechanisms in Refineries:

- Mechanical Fatigue

* What's Mechanical Fatigue?

* How Stress Raisers (Surface Defects) Start Point of Mechanical Fatigue?

* Vibration Induced Fatigue ( Type of Mechanical Fatigue)

* Affected Equipment / Piping Affected Locations to Fatigue Damages..

* Q & A

- Corrosion Fatigue : What's Corrosion Fatigue?

*  Difference in Mechanical & Corrosion Fatigue.

* Effect of Corrosion on S-N Curve (Stainless Steel & Carbon Steels)

* How to Identify Corrosion Fatigue & Mechanical Fatigue?

* What's the Driving Force for Corrosion Fatigue and why Fatigue / Corrosion Fatigue Cracks are Straight?

* Micrography Detail of Corrosion Fatigue Cracks.

- Environmentally Affected Cracking .

-  Environmentally Affected Cracking Mechanism .

* Chloride Stress Corrosion Cracking (ClSCC)

* Q & A on ClSCC

* Impact of Chlorides on SS 316 (Catastrophic Pitting / Cracking)

* Morphology of ClSCC

* Mechanism of ClSCC

* Difference in ClSCC of SS 316 & Duplex Stainless Steels Morphology.

- Polythionic Acid Stress Corrosion Cracking (PTASCC)

* What's Sensitization in Austenitic Stainless Steels & Nickel Base Alloys

* PTASCC Mechanism

* When PTASCC Occurs & Its Mitigation.

* Why Austenitic Stainless Steels are not Reliable and give Surprizes?

* Morphology of PTASCC.

- Titanium Hydriding.

* Why Titanium is Resistant to Chloride Corrosion / Chloride Stress Corrosion Cracking.?

* How Titanium Hydriding Occurs & Causes Brittle Fracture?

* Factors Affecting Titanium Hydriding.

* Mechanism of Titanium Hydriding.

* Affected Equipment / Components by Titanium Hydriding.

- Brittle Fractur (Poor Toughness & Poor Ductility)

* Three Factors Causing Brittle Fracture.

* Important Factors Affecting DBTT and Causing Brittle Fracture in Carbon & Low Alloy Steels.

- Erosion / Erosion - Corrosion Cycle

* Factors Affecting Erosion Corrosion

- Cavitation : A form of Erosion- Corrosion.

* Materials Affected by Cavitation

*  Cavitation Damage Mechanism

* Prevention / Mitigating Cavitation

- 475 Deg. C Embrittlement

* What's Alpha Prime?

* Mechanism of 475 Deg. C Embrittlement

* Affected Material By 475 Deg.C Embrittlement.

* Q & A : Why Duplex Stainless Steels Application Limit to Below 280 Deg. C. Temperature.

* What's the Difference in Temper & 475 Deg. C embrittlement?

Over view of Damage Mechanisms in Refinery :

- Damage Mechanism : Galvanic Corrosion

- Damage Mechanism : Liquid Metal Embrittlement (LME)/ Liquid Metal Cracking (LMC)

* LME / LMC Mechanism

* Prevention/ Mitigation of LME

* When & How LME Occurs?

* Zinc Embrittlement of Austenitic Stainless Steel : Type 1 & Type 2

* Liquid Metal Embrittlement Mechanism

* Role of Electronegativity & Atomic Size in LME.

* Condition for LME .

* Copper Liquid Metal Causing LMC in Austenitic Stainless Steels.

* Three Stages of LME Mechanism

* Liquid Metal Couplings Causing LME

* Case Study : Algeria LNG Plant Explosion in Aluminium Heat Exchanger.

- Damage Mechanism : Dealloying

* Mechanism of dezincification & denickelification

* What's Dealloying (Dezincification / De-nickelification)   

* Morphology of Dezincification (Photographs)

*Combinations of alloys & environment susceptible to dealloying.

- Damage Mechanism : Graphitic Corrosion

- Damage Mechanism : Fuel Ash Corrosion (FAC)

* What's Fuel Ash Corrosion ?

* Sulfur Dew Point Corrosion -Erosion in economiser tubes in Boiler

* Morphology / Appearance of FAC Photographs

- Damage Mechanism : Thermal Fatigue

* What's Thermal Fatigue?

*Factors Affecting Thermal Fatigue.

* Prevention ? Mitigation of Thermal Fatigue

- Damage Mechanism : Thermal Shocks

* The magnitude of the temperature differential and the coefficient of thermal expansion result stress causing failure

* Affected unit & Equipment in refineries.

- Damage Mechanism : Graphitization

* Difference in Graphitization & Spheroidization

- Damage Mechanism: Temper Embrittlement

* Factor Affecting Temper Embrittlement

* J * factor &  X factor

- Damage Mechanism : Decarburization

* When does decarburization occurs

* Factors Affecting Decarburization

- Damage Mechanism : Carburization

* What's Carburization

* Material Affected by Carburization

* Carburization : Type of Metal Dusting damage mechanism

* Conditions Favoring Carburization

* Affected units / equipment

* Appearance / Morphology of Damage

* Preventing / Mitigating Carburization

- Damage Mechanism : Metal Dusting

* Metal Dusting Mechanisms

* Factors Affecting Carburization

* Affected Units / Equipment in Refineries

- Damage Mechanism : Nitriding   

- Damage Mechanism : Sulphate Stress Corrosion Cracking

- Damage Mechanism : Phosphoric Acid Corrosion

- Damage Mechanism : Amine Corrosion   

Corrosion Control & Its Management in Petroleum Refineries

Corrosivity of Crude Oil

- Selection of Crude as per the design & metallurgy of equipment in Refinery

* Corrosion Drivers : Oxidizing Agents Causing Corrosion & Stimulating Factors Expediting Corrosion for Corrosion Control during design Stage & Operating Stage for Corrosion Control in Refineries.

* Relative Corrosion Rate of Carbon steel in Oxygen, CO2 & H2S environment.

* Type of Probable Localized Corrosion in Austenitic Stainless Steels

* Probable General & Localized Corrosion in CS / LAS.

* Why Corrosion is a Complex Problem?

* Corrosion Dependence on Geography & Industrial Environment : Onshore, Offshore, Coastal & Marine Industrial.

- Crude Oil & Its Corrosivity

- Corrosives in Crude Oil Causing Corrosion of Equipment in Refineries.

* Brackish Water (Chlorides)

* Sweet Crude & Heavy Sour Crude

* Crude Processing in Downstream of CDU heater.

* Corrosion in CDU Heaters, Transfer Line, Main Column , Side Streams And Overhead System in Crude Distillation Unit.

* How Sour Crude is More Corrosive in Presence of Chlorides?

*Mitigating Chloride Corrosion in CDU Overhead?

* Why Corrosion Control by Neutralizer Amine & Vapor Phase Corrosion Inhibitor is Better Than Ammonia Injection.?

* Why Excess Dosing of Neutralizer Amine is Insidious to Corrosion Control?

* How Water Washing is the most effective method for controlling PH & Chlorides for O/H corrosion control?

* CO2 Sweet Corrosion & Its Mechanism.

* Sour Gas H2S Corrosion & Its Mechanism.

* Impact of Phantom Chlorides on Corrosion & Its Mitigation.

* Organic Acids (Naphthenic Acid ) Corrosion.

* Impact of Sulfur on Naphthenic Acid Corrosion (NAC).

* Mitigating NAC.

- Sour Water Corrosion (Acidic Corrosion)

* Classification of Severity of Sour Water Corrosion based on pH & H2S partial pressure as per ISO15156 (Part 2)

* Pitting Corrosion , HIC,  SCC, HSC , SSC in sour service.

* HIC & SWC & Blistering Mechanism in Sour Water Service

* Hydrogen Blister, HIC, SOHIC & Hydrogen Embrittlement

* What's Sulphide Stress Cracking?

* Sulphide Stress Cracking Mechanism.

*HIC Resistant Material Specification for Carbon Steel.

- Sulphidation : Corrosion due to Sulphur Compound .

* Sulphidation Corrosion in presence of Hydrogen.

* Sulphidation  Mechanism & Control.

* Factors Affecting Sulphidation Corrosion.

* Mitigating Sulphidation Corrosion.

* MCcnomy Curve & Sulphidation

* Draw Backs of MCconomy Curve and how it is being taken care in Couper - Gorman Curve?

* Effect of Silicon on Sulphidation in Carbon Steel (API RP -939C).

* Process & Design Modifications to Explore Turn Around Extension.

* Why Sulphidation / NAC are Unpredictable, Causing Fatalities.?

- Metallurgy for Processing Sour Crude / Naphthenic Acid Crude below dew point in crude distillation unit.

- Metallurgy for Processing Sour Crude above Dew Point.

- Bacteria Causing MIC in Crude Oil Storage.

* Mitigating MIC

* High Temperature Oxygen Corrosion.

- Over View of Refineries : Processing Units Classification in Refineries : Primary Units, Secondary & Auxiliary Units & Facilities.

- A Schematic Flow Diagram in a Petroleum Refinery

- Steps in Corrosion Control for Avoiding Catastrophes.         

Corrosion Control & Its Management in Atmospheric Crude & Vacuum Distillation Units in Refinery

- Classification of Processing Units in Refinery

- Corrosion Control & its Management in CDU & VDU

- Process in Crude Distillation & Vacuum Distillation Unit

- Difference in Debottlenecking & Revamping.

- Why low temperature distillation in CDU & VDU?

- Process Flow diagram of CDU & VDU

- Probable Corrosion & Metallurgical Degradation Damage Mechanisms in CDU & VDU.

- Overhead Corrosion Problems in CDU & VDU.

- Source of HCl in CDU Overhead.

- Source of Ammonia (NH3) in CDU Overhead.

- Source of Oxygen and its impact on corrosion.

- NH4Cl Corrosion in CDU Overhead System.

- Shock Condensation Corrosion Damage Mechanism in CDU Overhead System .

- Why Shock Condensation Corrosion  is insidious and how to control it?

- Why Overhead Corrosion Concerns are more in Single Drum system?

- CDU Overhead HCl Corrosion Control by Caustic Injection in D/S of main Column and why it is to be optimized?

- Corrosion Control in Reflux Piping : Wet Reflux Drum.

- Impact of Quantity & Quality of Water Wash in CDU Overhead System.

- Locations of Injections for best control of CDU O/H system.

- Effectiveness of injections through injection quill system.

- Effect of throughput in crude distillation unit.

- Remedial Measures to prevent erosion corrosion in CDU Overhead Piping, Condenser & Air Coolers.

- Impact of Low Velocity / Flow rate on corrosion & Its remediation.

- Process Flow diagram of CDU & VDU overhead double drum circuit.

- Desalting of Crude Oil : Why two stage desalting?

- Single & Double Overhead reflux drum design . Why Double Drum is Better than Single Drum? 

Corrosion Control & Its Management in CDU, VDU & FCCU

- Desalting of Crude

* Importance of desalting crude oil for corrosion control in primary & Secondary Units

* Why Double Stage Desalting

* Factors Affecting Desalting in Desalter

* Single Stage Vs Double Stage Desalting Comparison

- CDU Over head Corrosion

* Single Stage Single Drum VS Double Stage Double Drums Overhead Corrosion in CDU.

- Vacuum Distillation Unit

* Why Crude Distillation in two Stages and Why you need Vacuum?

- MOC in Vacuum Distillation Unit Column, Piping , Condensers & Other Equipment

* Corrosion in Vacuum Tower O/H System

* Vacuum Tower Overhead Corrosion Concerns.

* Probable Damage Mechanisms in Crude Distillation Units

- Stages of Corrosion Control : Corrosion Controlled, Cost Controlled & Catastrophes Reduced.

-  Inhibitors & Passivators

- Mechanism of Passivation

- High Temperature Corrosion & Metallurgical Degradation in Major Secondary Units in FCCU, DCU (Coker), Hydrocracker, Naphtha Hydro treater (NHT), & Hydrogen Reformer

- Fluid Catalytic Cracking Unit

* Principal Deterioration Mechanisms in FCCU

* High Temperature Corrosion VS Low Temperature Corrosion in FCCU

* Stress Relaxation Cracking Mechanism

* SRC during fabrication

* SRC during In-service

* Stress Assisted Grain Boundary Oxidation (SAGBO) Cracking.

* Why HIC produces Intergranular Fracture?

* Critical Factors Affecting SRC

* Affected Equipment by SRC

* Prevention & Mitigation of SRC: Why Difficult?

* Inspection & Examination for SRC detection .

- Metallurgical Degradation Mechanisms in Refineries & Petrochemicals : FCCU, Hydrogen Plant, Catalytic Reformer, Coker (Heater Tubes), Hydro-processing Plant, Sulfur Recovery Unit.

- Corrosion Control & Its Management in Fluid Catalytic Cracking Unit

- FCCU Process in Regenerators & Reactor

- Damage Mechanism in Regenerator & Its Piping

* Sigma Phase Embrittlement

* Why Welds are more prone to Sigma Embrittlement in 304H  Material.?

* How Carburization of Regenerator's Internal Components Occurs?

* PTASCC of Regenerator's  Internals

* Creep Damages in Regenerator

- FCCU Regenerator Cyclones Concerns & Remedies

- Regenerator Plenum Chamber Damage Mechanisms

-Regenerator's  Flue Gas Overhead Piping : 304 H Hot wall Design

- Sigma Phase Embrittlement

- Liquid Metal Embrittlement

- Thermal Fatigue Failures

- Support System : Spring Hangers & Pipe Support System

- Flue Gas O/H  Piping Mitered Elbow Embrittlement

- Why 304 H is better Material in Regenerator's Internal , Flue Gas Duct?

_ Sigma phase Embrittlement   

_       

Corrosion Control & Its Management in FCCU

- Fitness for Purpose Testing of Regenerator's Internals Component.

* Bend Test

* Tensile Test

* Charpy notch toughness test

- Why FCCU is called as " Heat Balanced Unit"

- Process Flow Diagram of FCCU.

- Corrosion & Metallurgical Degradation Damage Mechanisms in FCCU

* MOC & Process Flow Diagram of FCCU

* Operating Temperature in Process Flow Diagram.

- FCCU Main Equipment  Sections

* Riser Reactor Section

* Regenerator Section

* Flue Gas Section

* Main Fractionating Section

- Damage Mechanisms & Material of Construction (MOC) in FCCU

-  Probable Damage Mechanisms Identification in various equipment & Piping of FCCU

* Damage Mechanism : High Temperature Sulphidation - What's , where's , how to monitor & mitigate?

* Damage Mechanism : Carburization- What's , where's , How to monitor and mitigate?Sigma Phase

* Damage Mechanism : Metal Dusting - What's & Where's

* Microstructural Damages caused by high temperature exposure : What's & Where's, How to monitor & Mitigate?

. Graphitization

.  Sigma Phase Embrittlement

.  885 F (475 Deg. C)Embrittlement

. Creep

. Thermal Shock & Thermal Fatigue

. Sensitization in ASS & PTASCC

- Damage Mechanism : Graphitization : What's Where's

- Damage Mechanism : Sigma Phase Embrittlement - what's, where's

- Damage Mechanism : 475 deg. C Embrittlement : What's & Where's

- Damage Mechanism : High Temperature Creep : What's & Where's

- FCCU equipment Susceptible to high Temperature Creep.

- Damage Mechanism : Thermal Fatigue- What's & Where's

- Damage Mechanism : PTASCC - What's & Where's

- Edax Analysis of Grain Boundary Carbide  in sensitized ASS.

- Damage Mechanism : Chloride Stress Corrosion Cracking

- Micrograph : PTA SCC (IGC) & ClSCC (TGC) 

/

Corrosion Control & Its Management in Hydrocracker unit.

* Comparison of  major secondary units in refineries viz. FCCU, Coker & Hydrocracker

* Why Hydrocracker Unit ?

* What's Hydro Cracking?

* Primary Function of Hydrogen in Hydrocracker .

* Corrosion Control & Its Management in Hydro Cracking Unit.

* Hydro Cracker Configuration : Three type : Single Stage , Single Stage recycle , & 2 stage hydrocracker

* Process Flow Diagram of double stage Hydrocracker.

* Identification & Discussion on Probable Damage Mechanisms in Hydrocracker.

* Interaction of Hydrogen with Steels at elevated temperature Causing HTHA Damage Mechanism.

* HTHA Damage Mechanism in Hydrocracker.

* Hydrogen Embrittlement Damage Mechanism in ageing reactor in Hydro Cracker.

* High Temperature Sulfidation Corrosion (H2S Corrosion at High Temperature)

- Without Hydrogen

- With Hydrogen

* Temper Embrittlement damage mechanism in reactor in hydrocracker.

* Hydrogen Embrittlement in Reactor in Hydrocracker Unit.

* Ammonium Bisulphide / Ammonium Chloride Corrosion in Reactor Affluent   Air Fin Cooler in Hydrocracker.

* Metallurgy Selection & Damage Mechanism in Hydrocracke.

* Case study : SS 347 piping failure in Heaters in  Hydrocracker due to sigma embrittlement.

* Importance of 2 1/4 Cr- 1 MO -0.25V steel as MOC metallurgy of Reactor in Hydrocracker.

* Benefits of Vanadium modified 2 1/4 Cr - 1 Mo - 0.25 V steel .

* Conclusion